Patent Publication Number: US-11050027-B2

Title: Condensed cyclic compound and organic light-emitting device including the same

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
     This application claims a priority to Korean Patent Application No. 10-2013-0146414, filed on 28 Nov. 2013, and all the benefits accruing therefrom under 35 U.S.C. § 119, the content of which is incorporated herein in its entirety by reference. 
     BACKGROUND 
     1. Field 
     One or more embodiments relate to a condensed cyclic compound and an organic light-emitting device including the same. 
     2. Description of the Related Art 
     Organic light emitting devices (OLEDs) are self-emission devices that have wide viewing angles, high contrast ratios, short response time, excellent brightness, driving voltage, and response speed characteristics, and produce full-color images. 
     As an example, an organic light-emitting device includes an anode, a cathode, and an organic layer that is disposed between the anode and the cathode and further includes an emission layer. A hole transport region may be disposed between the anode and the emission layer, and an electron transport region may be disposed between the emission layer and the cathode. Holes provided from the anode may move toward the emission layer through the hole transport region, and electrons provided from the cathode may move toward the emission layer through the electron transport region. Carriers, such as holes and electrons, are recombined in the emission layer to produce excitons. These excitons change from an excited state to a ground state, thereby generating light. 
     Different types of OLEDs have been reported. However, there remains a need in OLEDs having one or more of low driving voltage, high efficiency, high brightness, and long lifespan. 
     SUMMARY 
     One or more embodiments relate to a novel condensed cyclic compound and an organic light-emitting device including the same. 
     An aspect provides a condensed cyclic compound represented by Formula 1: 
     
       
         
         
             
             
         
       
     
     wherein in Formula 1, 
     X 1  is N or C-[(L 1 ) a1 -(R 1 ) b1 ], 
     X 2  is N or C-[(L 2 ) a2 -(R 2 ) b2 ], 
     X 3  is N or C-[(L 3 ) a3 -(R 3 ) b3 ], 
     X 4  is N or C-[(L 4 ) a4 -(R 4 ) b4 ], 
     X 5  is N or C-[(L 5 ) a5 -(R 5 ) b5 ], 
     X 6  is N or C-[(L 6 ) a6 -(R 6 ) b6 ], 
     X 7  is N or C-[(L 7 ) a7 -(R 7 ) b7 ], 
     X 8  is N or C-[(L 8 ) a8 -(R 8 ) b8 ], 
     provided that at least one of X 1  to X 8  is N; 
     L 1  to L 8 , L 11 , and L 12  are each independently selected from a substituted or unsubstituted C 3 -C 10  cycloalkylene group, a substituted or unsubstituted C 2 -C 10  heterocycloalkylene group, a substituted or unsubstituted C 3 -C 10  cycloalkenylene group, a substituted or unsubstituted C 2 -C 10  heterocycloalkenylene group, a substituted or unsubstituted C 6 -C 60  arylene group, a substituted or unsubstituted C 2 -C 60  heteroarylene group, a substituted or unsubstituted divalent non-aromatic condensed polycyclic group, and a substituted or unsubstituted divalent non-aromatic hetero-condensed polycyclic group; 
     a1 to a8, a11, and a12 are each independently an integer from 0 to 3; 
     R 1  to R 8 , R 11 , and R 12  are each independently selected from a hydrogen, a deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, an amino group, an amidino group, a hydrazine group, a hydrazone group, a carboxylic acid or a salt thereof, a sulfonic acid group or a salt thereof, a phosphoric acid group or a salt thereof, a substituted or unsubstituted C 1 -C 60  alkyl group, a substituted or unsubstituted C 2 -C 60  alkenyl group, a substituted or unsubstituted C 2 -C 60  alkynyl group, a substituted or unsubstituted C 1 -C 60  alkoxy group, a substituted or unsubstituted C 3 -C 10  cycloalkyl group, a substituted or unsubstituted C 2 -C 10  heterocycloalkyl group, a substituted or unsubstituted C 3 -C 10  cycloalkenyl group, a substituted or unsubstituted C 2 -C 10  heterocycloalkenyl group, a substituted or unsubstituted C 6 -C 60  aryl group, a substituted or unsubstituted C 6 -C 60  aryloxy group, a substituted or unsubstituted C 6 -C 60  arythio group, a substituted or unsubstituted C 2 -C 60  heteroaryl group, a substituted or unsubstituted monovalent non-aromatic condensed polycyclic group, a substituted or unsubstituted monovalent non-aromatic condensed heteropolycyclic group, —N(Q 1 )(Q 2 ), —Si(Q 3 )(Q 4 )(Q 5 ), and —B(Q 6 )(Q 7 ); 
     b1 to b8, b11, and b12 are each independently an integer from 1 to 5; 
     wherein at least one of substituents of the substituted C 3 -C 10  cycloalkylene group, the substituted C 2 -C 10  heterocycloalkylene group, the substituted C 3 -C 10  cycloalkenylene group, the substituted C 2 -C 10  heterocycloalkenylene group, the substituted C 6 -C 60  arylene group, the substituted C 2 -C 60  heteroarylene group, the substituted divalent non-aromatic condensed polycyclic group, the substituted divalent non-aromatic condensed heteropolycyclic group, the substituted C 1 -C 60  alkyl group, the substituted C 2 -C 60  alkenyl group, the substituted C 2 -C 60  alkynyl group, the substituted C 1 -C 60  alkoxy group, the substituted C 3 -C 10  cycloalkyl group, the substituted C 2 -C 10  heterocycloalkyl group, the substituted C 3 -C 10  cycloalkenyl group, the substituted C 2 -C 10  heterocycloalkenyl group, the substituted C 6 -C 60  aryl group, the substituted C 6 -C 60  aryloxy group, the substituted C 6 -C 60  arythio group, the substituted C 2 -C 60  heteroaryl group, the substituted monovalent non-aromatic condensed polycyclic group, and the substituted monovalent non-aromatic condensed heteropolycyclic group is selected from 
     a deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, an amino group, an amidino group, a hydrazine group, a hydrazone group, a carboxylic acid or a salt thereof, a sulfonic acid group or a salt thereof, a phosphoric acid group or a salt thereof, a C 1 -C 60  alkyl group, a C 2 -C 60  alkenyl group, a C 2 -C 60  alkynyl group, and a C 1 -C 60  alkoxy group; 
     a C 1 -C 60  alkyl group, a C 2 -C 60  alkenyl group, a C 2 -C 60  alkynyl group, and a C 1 -C 60  alkoxy group, each substituted with at least one group selected from a deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, an amino group, an amidino group, a hydrazine group, a hydrazone group, a carboxylic acid or a salt thereof, a sulfonic acid group or a salt thereof, a phosphoric acid group or a salt thereof, a C 3 -C 10  cycloalkyl group, a C 2 -C 10  heterocycloalkyl group, a C 3 -C 10  cycloalkenyl group, a C 2 -C 10  heterocycloalkenyl group, a C 6 -C 60  aryl group, a C 6 -C 60  aryloxy group, a C 6 -C 60  arythio group, a C 2 -C 60  heteroaryl group, a monovalent non-aromatic condensed polycyclic group, a monovalent non-aromatic condensed heteropolycyclic group, —N(Q 11 )(Q 12 ), —Si(Q 13 )(Q 14 )(Q 15 ), and —B(Q 16 )(Q 17 ); 
     a C 3 -C 10  cycloalkyl group, a C 2 -C 10  heterocycloalkyl group, a C 3 -C 10  cycloalkenyl group, a C 2 -C 10  heterocycloalkenyl group, a C 6 -C 60  aryl group, a C 6 -C 60  aryloxy group, a C 6 -C 60  arythio group, a C 2 -C 60  heteroaryl group, a monovalent non-aromatic condensed polycyclic group, and a monovalent non-aromatic condensed heteropolycyclic group; and 
     a C 3 -C 10  cycloalkyl group, a C 2 -C 10  heterocycloalkyl group, a C 3 -C 10  cycloalkenyl group, a C 2 -C 10  heterocycloalkenyl group, a C 6 -C 60  aryl group, a C 6 -C 60  aryloxy group, a C 6 -C 60  arythio group, a C 2 -C 60  heteroaryl group, a monovalent non-aromatic condensed polycyclic group, a monovalent non-aromatic condensed heteropolycyclic group, each substituted with at least one group selected from a deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, an amino group, an amidino group, a hydrazine group, a hydrazone group, a carboxylic acid or a salt thereof, a sulfonic acid group or a salt thereof, a phosphoric acid group or a salt thereof, a C 1 -C 60  alkyl group, a C 2 -C 60  alkenyl group, a C 2 -C 60  alkynyl group, a C 1 -C 60  alkoxy group, a C 3 -C 10  cycloalkyl group, a C 2 -C 10  heterocycloalkyl group, a C 3 -C 10  cycloalkenyl group, a C 2 -C 10  heterocycloalkenyl group, a C 6 -C 60  aryl group, a C 6 -C 60  aryloxy group, a C 6 -C 60  arythio group, a C 2 -C 60  heteroaryl group, a monovalent non-aromatic condensed polycyclic group, a monovalent non-aromatic condensed heteropolycyclic group, —N(Q 21 )(Q 22 ), —Si(Q 23 )(Q 24 )(Q 25 ), and —B(Q 26 )(Q 27 ); and 
     —N(Q 31 )(Q 32 ), —Si(Q 33 )(Q 34 )(Q 35 ), and —B(Q 36 )(Q 37 ), wherein 
     Q 1  to Q 7 , Q 11  to Q 17 , Q 21  to Q 27 , and Q 31  to Q 37  are each independently selected from a hydrogen, a C 1 -C 60  alkyl group, a C 2 -C 60  alkenyl group, a C 2 -C 60  alkynyl group, a C 1 -C 60  alkoxy group, a C 3 -C 10  cycloalkyl group, a C 2 -C 10  heterocycloalkyl group, a C 3 -C 10  cycloalkenyl group, a C 2 -C 10  heterocycloalkenyl group, a C 6 -C 60  aryl group, a C 6 -C 60  aryloxy group, a C 6 -C 60  arythio group, a C 2 -C 60  heteroaryl group, a monovalent non-aromatic condensed polycyclic group, and a monovalent non-aromatic condensed heteropolycyclic group. 
     Another aspect provides an organic light-emitting device including: 
     a first electrode; 
     a second electrode; and 
     an organic layer disposed between the first electrode and the second electrode, 
     wherein the organic layer includes an emission layer and at least one of the condensed cyclic compound represented by Formula 1. 
     The condensed cyclic compound may be included in the emission layer, and the emission layer may further include a dopant, and the condensed cyclic compound included in the emission layer may act as a host. Herein, the emission layer may be a green emission layer emitting green light, and the dopant may be a phosphorescent dopant that emits light according to a phosphorescent mechanism. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       These and/or other aspects will become apparent and more readily appreciated from the following description of the embodiments, taken in conjunction with the accompanying drawings in which: 
         FIG. 1  is a schematic view of an organic light-emitting device according to an embodiment; 
         FIG. 2  is a graph of weight (percent, %) and derivative weight (percent per degree Centigrade, %/° C.) versus temperature (degrees Centigrade, ° C.) showing thermo gravimetric analysis (TGA) data of Compound 1; 
         FIG. 3  is a graph of heat flow (watts per gram, W/g) versus temperature (degrees Centigrade, ° C.) showing differential scanning calorimetry (DSC) data of Compound 1; 
         FIG. 4  is a graph of weight (percent, %) and derivative weight (percent per degree Centigrade, %/° C.) versus temperature (degrees Centigrade, ° C.) showing TGA data of Compound 129; and 
         FIG. 5  is a graph of heat flow (watts per gram, W/g) versus temperature (degrees Centigrade, ° C.) showing DSC data of Compound 129. 
     
    
    
     DETAILED DESCRIPTION 
     Reference will now be made in detail to embodiments, examples of which are illustrated in the accompanying drawings, wherein like reference numerals refer to like elements throughout. In this regard, the present embodiments may have different forms and should not be construed as being limited to the descriptions set forth herein. Accordingly, the embodiments are merely described below, by referring to the figures, to explain aspects of the present description. Expressions such as “at least one of,” when preceding a list of elements, modify the entire list of elements and do not modify the individual elements of the list. 
     It will be understood that when an element is referred to as being “on” another element, it can be directly in contact with the other element or intervening elements may be present therebetween. In contrast, when an element is referred to as being “directly on” another element, there are no intervening elements present. 
     It will be understood that, although the terms first, second, third etc. may be used herein to describe various elements, components, regions, layers, and/or sections, these elements, components, regions, layers, and/or sections should not be limited by these terms. These terms are only used to distinguish one element, component, region, layer, or section from another element, component, region, layer, or section. Thus, a first element, component, region, layer, or section discussed below could be termed a second element, component, region, layer, or section without departing from the teachings of the present embodiments. 
     The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting. As used herein, the singular forms “a,” “an,” and “the” are intended to include the plural forms as well, unless the context clearly indicates otherwise. 
     The term “or” means “and/or.” It will be further understood that the terms “comprises” and/or “comprising,” or “includes” and/or “including” when used in this specification, specify the presence of stated features, regions, integers, steps, operations, elements, and/or components, but do not preclude the presence or addition of one or more other features, regions, integers, steps, operations, elements, components, and/or groups thereof. 
     Unless otherwise defined, all terms (including technical and scientific terms) used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this general inventive concept belongs. It will be further understood that terms, such as those defined in commonly used dictionaries, should be interpreted as having a meaning that is consistent with their meaning in the context of the relevant art and the present disclosure, and will not be interpreted in an idealized or overly formal sense unless expressly so defined herein. 
     Exemplary embodiments are described herein with reference to cross section illustrations that are schematic illustrations of idealized embodiments. As such, variations from the shapes of the illustrations as a result, for example, of manufacturing techniques and/or tolerances, are to be expected. Thus, embodiments described herein should not be construed as limited to the particular shapes of regions as illustrated herein but are to include deviations in shapes that result, for example, from manufacturing. For example, a region illustrated or described as flat may, typically, have rough and/or nonlinear features. Moreover, sharp angles that are illustrated may be rounded. Thus, the regions illustrated in the figures are schematic in nature and their shapes are not intended to illustrate the precise shape of a region and are not intended to limit the scope of the present claims. 
     A condensed cyclic compound according to an embodiment is represented by Formula 1 below: 
     
       
         
         
             
             
         
       
     
     X 1  in Formula 1 is N or C-[(L 1 ) a1 -(R 1 ) b1 ], 
     X 2  is N or C-[(L 2 ) a2 -(R 2 ) b2 ], 
     X 3  is N or C-[(L 3 ) a3 -(R 3 ) b3 ], 
     X 4  is N or C-[(L 4 ) a4 -(R 4 ) b4 ], 
     X 5  is N or C-[(L 5 ) a5 -(R 5 ) b5 ], 
     X 6  is N or C-[(L 6 ) a6 -(R 6 ) b6 ], 
     X 7  is N or C-[(L 7 ) a7 -(R 7 ) b7 ], 
     X 8  is N or C-[(L 8 ) a8 -(R 8 ) b8 ], and 
     at least one of X 1  to X 8  is N. 
     According to an embodiment, at least one of X 5  to X 8  in Formula 1 may be N. For example, X 6  and X 8  in Formula 1 may be N, but are not limited thereto. 
     For example, in Formula 1, 
     X 1  may be C-[(L 1 ) a1 -(R 1 ) b1 ], 
     X 2  may be C-[(L 2 ) a2 -(R 2 ) b2 ], 
     X 3  may be C-[(L 3 ) a3 -(R 3 ) b3 ], 
     X 4  may be C-[(L 4 ) a4 -(R 4 ) b4 ], 
     X 5  may be C-[(L 5 ) a5 -(R 5 ) b5 ], 
     X 6  may be N, X 7  may be C-[(L 7 ) a7 -(R 7 ) b7 ], and 
     X 8  may be N, but they are not limited thereto. 
     L 1  to L 8 , L 11 , and L 12  in Formula 1 may be each independently selected from a substituted or unsubstituted C 3 -C 10  cycloalkylene group, a substituted or unsubstituted C 2 -C 10  heterocycloalkylene group, a substituted or unsubstituted C 3 -C 10  cycloalkenylene group, a substituted or unsubstituted C 2 -C 10  heterocycloalkenylene group, a substituted or unsubstituted C 6 -C 60  arylene group, a substituted or unsubstituted C 2 -C 60  heteroarylene group, a substituted or unsubstituted divalent non-aromatic condensed polycyclic group, and a substituted or unsubstituted divalent non-aromatic hetero-condensed polycyclic group. 
     According to an embodiment, L 1  to L 8 , L 11 , and L 12  in Formula 1 are each independently selected from 
     a phenylene group, a pentalenylene group, an indenylene group, a naphthylene group, an azulenylene group, a heptalenylene group, an indacenylene group, an acenaphthylene group, a fluorenylene group, a spiro-fluorenylene group, a phenalenylene group, a phenanthrenylene group, an anthracenylene group, a fluoranthrenylene group, a triphenylenylene group, a pyrenylene group, a chrysenylene group, a naphthacenylene group, a picenylene group, a perylenylene group, a pentaphenylene group, a hexacenylene group, a pyrrolylene group, an imidazolylene group, a pyrazolylene group, a pyridinylene group, a pyrazinylene group, a pyrimidinylene group, a pyridazinylene group, an isoindolylene group, an indolylene group, an indazolylene group, a purinylene group, a quinolinylene group, an isoquinolinylene group, a benzoquinolinylene group, a phthalazinylene group, a naphthyridinylene group, a quinoxalinylene group, a quinazolinylene group, a cinnolinylene group, a carbazolylene group, a phenanthridinylene group, an acridinylene group, a phenanthrolinylene group, a phenazinylene group, a benzooxazolylene group, a benzoimidazolylene group, a furanylene group, a benzofuranylene group, a thiophenylene group, a benzothiophenylene group, a thiazolylene group, an isothiazolylene group, a benzothiazolylene group, an isoxazolylene group, an oxazolylene group, a triazolylene group, a tetrazolylene group, a oxadiazolylene group, a triazinylene group, a dibenzofuranylene group, a dibenzothiophenylene group, a benzocarbazolyl group, a dibenzocarbazolyl group, an imidazopyrimidinylene group, and an imidazopyridinylene group; and a phenylene group, a pentalenylene group, an indenylene group, a naphthylene group, an azulenylene group, a heptalenylene group, an indacenylene group, an acenaphthylene group, a fluorenylene group, a spiro-fluorenylene group, a phenalenylene group, a phenanthrenylene group, an anthracenylene group, a fluoranthrenylene group, a triphenylenylene group, a pyrenylene group, a chrysenylene group, a naphthacenylene group, a picenylene group, a perylenylene group, a pentaphenylene group, a hexacenylene group, a pyrrolylene group, an imidazolylene group, a pyrazolylene group, a pyridinylene group, a pyrazinylene group, a pyrimidinylene group, a pyridazinylene group, an isoindolylene group, an indolylene group, an indazolylene group, a purinylene group, a quinolinylene group, an isoquinolinylene group, a benzoquinolinylene group, a phthalazinylene group, a naphthyridinylene group, a quinoxalinylene group, a quinazolinylene group, a cinnolinylene group, a carbazolylene group, a phenanthridinylene group, an acridinylene group, a phenanthrolinylene group, a phenazinylene group, a benzooxazolylene group, a benzoimidazolylene group, a furanylene group, a benzofuranylene group, a thiophenylene group, a benzothiophenylene group, a thiazolylene group, an isothiazolylene group, a benzothiazolylene group, an isoxazolylene group, an oxazolylene group, a triazolylene group, a tetrazolylene group, a oxadiazolylene group, a triazinylene group, a dibenzofuranylene group, a dibenzothiophenylene group, a benzocarbazolyl group, a dibenzocarbazolyl group, an imidazopyrimidinylene group, and an imidazopyridinylene group, each substituted with at least one group selected from 
     a deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, an amino group, an amidino group, a hydrazine group, a hydrazone group, a carboxylic acid or a salt thereof, a sulfonic acid or a salt thereof, a phosphoric acid or a salt thereof, a C 1 -C 20  alkyl group, a C 1 -C 20  alkoxy group, a C 6 -C 20  aryl group, a C 2 -C 60  heteroaryl group, a monovalent non-aromatic condensed polycyclic group, a monovalent non-aromatic condensed heterocyclic group, and —Si(Q 33 )(Q 34 )(Q 35 ), wherein 
     Q 33  to Q 35  may be each independently selected from a hydrogen, a C 1 -C 20  alkyl group, a C 1 -C 20  alkoxy group, a phenyl group, a naphthyl group, an anthracenyl group, a pyrenyl group, a phenanthrenyl group, a fluorenyl group, a carbazolyl group, a benzocarbazolyl group, a dibenzocarbazolyl group, a pyridinyl group, a pyrimidinyl group, a pyrazinyl group, a pyridazinyl group, a triazinyl group, a quinolinyl group, an isoquinolinyl group, a phthalazinyl group, a quinoxalinyl group, a cynolinyl group, and a quinazolinyl group. 
     According to another embodiment, in Formula 1, L 1  to L 8 , L 11 , and L 12  are each independently selected from Formulae 2-1 to 2-33: 
     
       
         
         
             
             
         
       
       
         
         
             
             
         
       
       
         
         
             
             
         
       
     
     wherein in Formulae 2-1 to 2-33, 
     Y 1  is O, S, S(═O), S(═O) 2 , C(Z 3 )(Z 4 ), N(Z 5 ), or Si(Z 6 )(Z 7 ); 
     Z 1  to Z 7  may be each independently selected from a hydrogen, a deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, an amino group, an amidino group, a hydrazine group, a hydrazone group, a carboxylic acid or a salt thereof, a sulfonic acid group or a salt thereof, a phosphoric acid group or a salt thereof, a C 1 -C 20  alkyl group, a C 1 -C 20  alkoxy group, a phenyl group, a naphthyl group, an anthracenyl group, a triphenylenyl group, a pyrenyl group, a phenanthrenyl group, a fluorenyl group, a chrysenyl group, a carbazolyl group, a benzocarbazolyl group, a dibenzocarbazolyl group, a dibenzofuranyl group, a dibenzothiophenyl group, a pyridinyl group, a pyrimidinyl group, a triazinyl group, a quinolinyl group, an isoquinolinyl group, a quinazolinyl group, a quinoxalinyl group, a biphenyl group, and —Si(Q 33 )(Q 34 )(Q 35 ); 
     Q 33  to Q 35  may be each independently selected from a hydrogen, a C 1 -C 20  alkyl group, a C 1 -C 20  alkoxy group, a phenyl group, a naphthyl group, an anthracenyl group, a pyrenyl group, a phenanthrenyl group, a fluorenyl group, a chrysenyl group, a carbazolyl group, a benzocarbazolyl group, a dibenzocarbazolyl group, a dibenzofuranyl group, a dibenzothiophenyl group, a pyridinyl group, a pyrimidinyl group, a triazinyl group, a quinolinyl group, an isoquinolinyl group, a quinazolinyl group, and a quinoxalinyl group; and 
     d1 may be an integer of 1 to 4, 
     d2 may be an integer of 1 to 3, 
     d3 may be an integer of 1 to 6, 
     d4 may be an integer of 1 to 8; 
     d5 may be an integer of 1 or 2, 
     d6 may be an integer of 1 to 5, and 
     * and *′ may each indicate a binding site to a neighboring atom. 
     For example, 
     * in Formulae 2-1 to 2-33 indicates a binding site to the core of Formula 1 or each of neighboring L 1  to L 8 , L 11 , and L 12 , and 
     *′ in Formulae 2-1 to 2-33 indicates a binding site to each of neighboring L 1  to L 8 , L 11 , and L 12  or each of R 1  to R 8 , R 11 , and R 12 . 
     According to another embodiment, L 1  to L 8 , L 11 , and L 12  in Formula 1 are each independently selected from Formulae 3-1 to 3-38: 
     
       
         
         
             
             
         
       
       
         
         
             
             
         
       
       
         
         
             
             
         
       
       
         
         
             
             
         
       
       
         
         
             
             
         
       
     
     wherein in Formulae 3-1 to 3-38, 
     * and *′ each indicates a binding site to a neighboring atom. 
     a1 in Formula 1 indicates the number of L 1 , and may be 0, 1, 2, or 3, for example, 0, 1 or 2. When a1 is 0, L 1  indicates a single bond. When a1 is 2 or more, groups L 1  may be identical or different. L 2  to L 8 , L 11 , and L 12  may be understood by referring to the description provided in connection with L 1  and the structure of Formula 1. 
     R 1  to R 8 , R 11 , and R 12  in Formula 1 may be each independently selected from a hydrogen, a deuterium, —F (fluoro group), —Cl (chloro group), —Br (bromo group), —I (iodo group), a hydroxyl group, a cyano group, a nitro group, an amino group, an amidino group, a hydrazine group, a hydrazone group, a carboxylic acid or a salt thereof, a sulfonic acid group or a salt thereof, a phosphoric acid group or a salt thereof, a substituted or unsubstituted C 1 -C 60  alkyl group, a substituted or unsubstituted C 2 -C 60  alkenyl group, a substituted or unsubstituted C 2 -C 60  alkynyl group, a substituted or unsubstituted C 1 -C 60  alkoxy group, a substituted or unsubstituted C 3 -C 10  cycloalkyl group, a substituted or unsubstituted C 2 -C 10  heterocycloalkyl group, a substituted or unsubstituted C 3 -C 10  cycloalkenyl group, a substituted or unsubstituted C 2 -C 10  heterocycloalkenyl group, a substituted or unsubstituted C 6 -C 60  aryl group, a substituted or unsubstituted C 6 -C 60  aryloxy group, a substituted or unsubstituted C 6 -C 60  arythio group, a substituted or unsubstituted C 2 -C 60  heteroaryl group, a substituted or unsubstituted monovalent non-aromatic condensed polycyclic group, a substituted or unsubstituted monovalent non-aromatic condensed heteropolycyclic group, —N(Q 1 )(Q 2 ), —Si(Q 3 )(Q 4 )(Q 5 ), and —B(Q 6 )(Q 7 ). 
     According to an embodiment, R 1  to R 8  in Formula 1 are not a hydrogen at the same time. 
     According to an embodiment, L 1  to L 8 , L 11 , and L 12  in Formula 1 may be each independently selected from a hydrogen, a deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, an amino group, an amidino group, a hydrazine group, a hydrazone group, a carboxylic acid or a salt thereof, a sulfonic acid group or a salt thereof, a phosphoric acid group or a salt thereof, a C 1 -C 20  alkyl group, and a C 1 -C 20  alkoxy group; 
     a C 1 -C 20  alkyl group and a C 1 -C 20  alkoxy group, each substituted with at least one group selected from a deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, an amino group, an amidino group, a hydrazine group, a hydrazone group, a carboxylic acid or a salt thereof, a sulfonic acid group or a salt thereof, and a phosphoric acid group or a salt thereof; 
     a phenyl group, a pentalenyl group, an indenyl group, a naphthyl group, an azulenyl group, a heptalenyl group, an indacenyl group, an acenaphthyl group, a fluorenyl group, a spiro-fluorenyl group, a benzofluorenyl group, a dibenzofluorenyl group, a phenalenyl group, a phenanthrenyl group, an anthracenyl group, a fluoranthenyl group, a triphenylenyl group, a pyrenyl group, a chrysenyl group, a naphthacenyl group, a picenyl group, a perylenyl group, a pentaphenyl group, a hexacenyl group, a pentacenyl group, a rubicenyl group, a coronenyl group, an ovalenyl group, a pyrrolyl group, a thiophenyl group, a furanyl group, an imidazolyl group, a pyrazolyl group, a thiazolyl group, an isothiazolyl group, an oxazolyl group, an isooxazolyl group, a pyridinyl group, a pyrazinyl group, a pyrimidinyl group, a pyridazinyl group, an isoindolyl group, an indolyl group, an indazolyl group, a purinyl group, a quinolinyl group, an isoquinolinyl group, a benzoquinolinyl group, a phthalazinyl group, a naphthyridinyl group, a quinoxalinyl group, a quinazolinyl group, a cinnolinyl group, a carbazolyl group, a phenanthridinyl group, an acridinyl group, a phenanthrolinyl group, a phenazinyl group, a benzoimidazolyl group, a benzofuranyl group, a benzothiophenyl group, an isobenzothiazolyl group, a benzooxazolyl group, an isobenzooxazolyl group, a triazolyl group, a tetrazolyl group, an oxadiazolyl group, a triazinyl group, a dibenzofuranyl group, a dibenzothiophenyl group, a benzocarbazolyl group, a dibenzocarbazolyl group, an imidazopyridinyl group, an imidazopyrimidinyl group, a benzofurocarbazolyl group, and a benzothiolocarbazolyl group; 
     a phenyl group, a pentalenyl group, an indenyl group, a naphthyl group, an azulenyl group, a heptalenyl group, an indacenyl group, an acenaphthyl group, a fluorenyl group, a spiro-fluorenyl group, a benzofluorenyl group, a dibenzofluorenyl group, a phenalenyl group, a phenanthrenyl group, an anthracenyl group, a fluoranthenyl group, a triphenylenyl group, a pyrenyl group, a chrysenyl group, a naphthacenyl group, a picenyl group, a perylenyl group, a pentaphenyl group, a hexacenyl group, a pentacenyl group, a rubicenyl group, a coronenyl group, an ovalenyl group, a pyrrolyl group, a thiophenyl group, a furanyl group, an imidazolyl group, a pyrazolyl group, a thiazolyl group, an isothiazolyl group, an oxazolyl group, an isooxazolyl group, a pyridinyl group, a pyrazinyl group, a pyrimidinyl group, a pyridazinyl group, an isoindolyl group, an indolyl group, an indazolyl group, a purinyl group, a quinolinyl group, an isoquinolinyl group, a benzoquinolinyl group, a phthalazinyl group, a naphthyridinyl group, a quinoxalinyl group, a quinazolinyl group, a cinnolinyl group, a carbazolyl group, a phenanthridinyl group, an acridinyl group, a phenanthrolinyl group, a phenazinyl group, a benzoimidazolyl group, a benzofuranyl group, a benzothiophenyl group, an isobenzothiazolyl group, a benzooxazolyl group, an isobenzooxazolyl group, a triazolyl group, a tetrazolyl group, an oxadiazolyl group, a triazinyl group, a dibenzofuranyl group, a dibenzothiophenyl group, a benzocarbazolyl group, a dibenzocarbazolyl group, an imidazopyridinyl group, an imidazopyrimidinyl group, a benzofurocarbazolyl group, and a benzothiolocarbazolyl group, each substituted with at least one group selected from a deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, an amino group, an amidino group, a hydrazine group, a hydrazone group, a carboxylic acid or a salt thereof, a sulfonic acid group or a salt thereof, a phosphoric acid group or a salt thereof, a C 1 -C 20  alkyl group, a C 1 -C 20  alkoxy group, —Si(Q 33 )(Q 34 )(Q 35 ), a phenyl group, a pentalenyl group, an indenyl group, a naphthyl group, an azulenyl group, a heptalenyl group, an indacenyl group, an acenaphthyl group, a fluorenyl group, a spiro-fluorenyl group, a benzofluorenyl group, a dibenzofluorenyl group, a phenalenyl group, a phenanthrenyl group, an anthracenyl group, a fluoranthenyl group, a triphenylenyl group, a pyrenyl group, a chrysenyl group, a naphthacenyl group, a pycenyl group, a perylenyl group, a pentaphenyl group, a hexacenyl group, a pentacenyl group, a rubicenyl group, a coronenyl group, an ovalenyl group, a pyrrolyl group, a thiophenyl group, a furanyl group, an imidazolyl group, a pyrazolyl group, a thiazolyl group, an isothiazolyl group, an oxazolyl group, an isoxazole group, a pyridinyl group, a pyrazinyl group, a pyrimidinyl group, a pyridazinyl group, an isoindolyl group, an indolyl group, an indazolyl group, a purinyl group, a quinolinyl group, an isoquinolinyl group, a benzoquinolinyl group, a phthalazinyl group, a naphthylidinyl group, a quinoxalinyl group, a quinazolinyl group, a cynolinyl group, a carbazolyl group, a phenanthridinyl, an acridinyl group, a phenanthrolinyl group, a phenazinyl group, a benzoimidazolyl group, a benzofuranyl group, a benzothiophenyl group, an isobenzothiazolyl group, a benzooxazolyl group, an isobenzooxazolyl group, a triazolyl group, a tetrazolyl group, an oxadiazolyl group, a triazinyl group, a dibenzofuranyl group, a dibenzothiophenyl group, a benzocarbazolyl group, a dibenzocarbazolyl group, an imidazopyridinyl group, an imidazopyrimidinyl group, and a biphenyl group; and 
     —Si(Q 3 )(Q 4 )(Q 5 ); 
     wherein Q 3  to Q 5  and Q 33  to Q 35  may be each independently selected from a hydrogen, a C 1 -C 20  alkyl group, a C 1 -C 20  alkoxy group, a phenyl group, a naphthyl group, an anthracenyl group, a pyrenyl group, a phenanthrenyl group, a fluorenyl group, a chrysenyl group, a carbazolyl group, a benzocarbazolyl group, a dibenzocarbazolyl group, a dibenzofuranyl group, a dibenzothiophenyl group, a pyridinyl group, a pyrimidinyl group, a triazinyl group, a quinolinyl group, an isoquinolinyl group, a quinazolinyl group, and a quinoxalinyl group. 
     For example, R 1  to R 8 , R 11 , and R 12  in Formula 1 may be each independently selected from 
     a hydrogen, a deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, an amino group, an amidino group, a hydrazine group, a hydrazone group, a carboxylic acid or a salt thereof, a sulfonic acid group or a salt thereof, a phosphoric acid group or a salt thereof, a C 1 -C 20  alkyl group, and a C 1 -C 20  alkoxy group; 
     a C 1 -C 20  alkyl group and a C 1 -C 20  alkoxy group, each substituted with at least one group selected from a deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, an amino group, an amidino group, a hydrazine group, a hydrazone group, a carboxylic acid or a salt thereof, a sulfonic acid group or a salt thereof and a phosphoric acid group or a salt thereof; 
     a phenyl group, a naphthyl group, a fluorenyl group, a spiro-fluorenyl group, a benzofluorenyl group, a dibenzofluorenyl group, a phenalenyl group, a phenanthrenyl group, an anthracenyl group, a fluoranthenyl group, a triphenylenyl group, a pyrenyl group, a chrysenyl group, a pycenyl group, a pyridinyl group, a pyrazinyl group, a pyrimidinyl group, a pyridazinyl group, a quinolinyl group, an isoquinolinyl group, a benzoquinolinyl group, a quinoxalinyl group, a quinazolinyl group, a carbazolyl group, a phenanthridinyl group, a phenanthrolinyl group, a benzoimidazolyl group, a benzofuranyl group, a benzothiophenyl group, an isobenzothiazolyl group, a benzooxazolyl group, an isobenzooxazolyl group, a triazolyl group, an oxadiazolyl group, a triazinyl group, a dibenzofuranyl group, a dibenzothiophenyl group, a benzocarbazolyl group, a dibenzocarbazolyl group, an imidazopyridinyl group, an imidazopyrimidinyl group, a benzofurocarbazolyl group, and a benzothiolocarbazolyl group; and 
     a phenyl group, a naphthyl group, a fluorenyl group, a spiro-fluorenyl group, a benzofluorenyl group, a dibenzofluorenyl group, a phenalenyl group, a phenanthrenyl group, an anthracenyl group, a fluoranthenyl group, a triphenylenyl group, a pyrenyl group, a chrysenyl group, a pycenyl group, a pyridinyl group, a pyrazinyl group, a pyrimidinyl group, a pyridazinyl group, a quinolinyl group, an isoquinolinyl group, a benzoquinolinyl group, a quinoxalinyl group, a quinazolinyl group, a carbazolyl group, a phenanthridinyl group, a phenanthrolinyl group, a benzoimidazolyl group, a benzofuranyl group, a benzothiophenyl group, an isobenzothiazolyl group, a benzooxazolyl group, an isobenzooxazolyl group, a triazolyl group, an oxadiazolyl group, a triazinyl group, a dibenzofuranyl group, a dibenzothiophenyl group, a benzocarbazolyl group, a dibenzocarbazolyl group, an imidazopyridinyl group, an imidazopyrimidinyl group, a benzofurocarbazolyl group, and a benzothiolocarbazolyl group, each substituted with at least one group selected from 
     a deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, an amino group, an amidino group, a hydrazine group, a hydrazone group, a carboxylic acid or a salt thereof, a sulfonic acid group or a salt thereof, a phosphoric acid group or a salt thereof, a C 1 -C 20  alkyl group, a C 1 -C 20  alkoxy group, and —Si(Q 33 )(Q 34 )(Q 35 ), a phenyl group, a naphthyl group, a fluorenyl group, a spiro-fluorenyl group, a benzofluorenyl group, a dibenzofluorenyl group, a phenalenyl group, a phenanthrenyl group, an anthracenyl group, a fluoranthenyl group, a triphenylenyl group, a pyrenyl group, a chrysenyl group, a pycenyl group, a pyridinyl group, a pyrazinyl group, a pyrimidinyl group, a pyridazinyl group, a quinolinyl group, an isoquinolinyl group, a benzoquinolinyl group, a quinoxalinyl group, a quinazolinyl group, a carbazolyl group, a phenanthridinyl group, a phenanthrolinyl group, a benzoimidazolyl group, a benzofuranyl group, a benzothiophenyl group, an isobenzothiazolyl group, a benzooxazolyl group, an isobenzooxazolyl group, a triazolyl group, an oxadiazolyl group, a triazinyl group, a dibenzofuranyl group, a dibenzothiophenyl group, a benzocarbazolyl group, a dibenzocarbazolyl group, an imidazopyridinyl group, and an imidazopyrimidinyl group. 
     Q 33  to Q 35  may be each independently selected from a hydrogen, a C 1 -C 20  alkyl group, a C 1 -C 20  alkoxy group, a phenyl group, a naphthyl group, an anthracenyl group, a pyrenyl group, a phenanthrenyl group, a fluorenyl group, a chrysenyl group, a carbazolyl group, a benzocarbazolyl group, a dibenzocarbazolyl group, a dibenzofuranyl group, a dibenzothiophenyl group, a pyridinyl group, a pyrimidinyl group, a triazinyl group, a quinolinyl group, an isoquinolinyl group, a quinazolinyl group, and a quinoxalinyl group. 
     As another example, R 1  to R 5  in Formula 1 may be each independently selected from 
     a hydrogen, a deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, an amino group, an amidino group, a hydrazine group, a hydrazone group, a carboxylic acid or a salt thereof, a sulfonic acid group or a salt thereof, a phosphoric acid group or a salt thereof, a C 1 -C 20  alkyl group, and a C 1 -C 20  alkoxy group; 
     a C 1 -C 20  alkyl group and a C 1 -C 20  alkoxy group, each substituted with at least one group selected from a deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, an amino group, an amidino group, a hydrazine group, a hydrazone group, a carboxylic acid or a salt thereof, a sulfonic acid group or a salt thereof and a phosphoric acid group or a salt thereof; and 
     Formulae 4-1 to 4-60 below; 
     R 11  and R 12  may be each independently selected from 
     a C 1 -C 20  alkyl group and a C 1 -C 20  alkoxy group; 
     a C 1 -C 20  alkyl group and a C 1 -C 20  alkoxy group, each substituted with at least one group selected from a deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, an amino group, an amidino group, a hydrazine group, a hydrazone group, a carboxylic acid or a salt thereof, a sulfonic acid group or a salt thereof, and a phosphoric acid group or a salt thereof; and 
     Formulae 4-1 to 4-60 below, but they are not limited thereto: 
     
       
         
         
             
             
         
       
       
         
         
             
             
         
       
       
         
         
             
             
         
       
       
         
         
             
             
         
       
       
         
         
             
             
         
       
       
         
         
             
             
         
       
       
         
         
             
             
         
       
       
         
         
             
             
         
       
     
     wherein in Formulae 4-1 to 4-60, 
     Y 31  is O, S, C(Z 33 )(Z 34 ), N(Z 35 ), or Si(Z 36 )(Z 37 ); 
     Z 31  to Z 39  may be each independently selected from a hydrogen, a deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, an amino group, an amidino group, a hydrazine group, a hydrazone group, a carboxylic acid or a salt thereof, a sulfonic acid group or a salt thereof, a phosphoric acid group or a salt thereof, a C 1 -C 20  alkyl group, a C 1 -C 20  alkoxy group, —Si(Q 33 )(Q 34 )(Q 35 ), a phenyl group, a naphthyl group, a fluorenyl group, a spiro-fluorenyl group, a benzofluorenyl group, a dibenzofluorenyl group, a phenalenyl group, a phenanthrenyl group, an anthracenyl group, a fluoranthenyl group, a triphenylenyl group, a pyrenyl group, a chrysenyl group, a pycenyl group, a pyridinyl group, a pyrazinyl group, a pyrimidinyl group, a pyridazinyl group, a quinolinyl group, an isoquinolinyl group, a benzoquinolinyl group, a quinoxalinyl group, a quinazolinyl group, a carbazolyl group, a phenanthridinyl group, a phenanthrolinyl group, a benzoimidazolyl group, a benzofuranyl group, a benzothiophenyl group, an isobenzothiazolyl group, a benzooxazolyl group, an isobenzooxazolyl group, a triazolyl group, an oxadiazolyl group, a triazinyl group, a dibenzofuranyl group, a dibenzothiophenyl group, a benzocarbazolyl group, a dibenzocarbazolyl group, an imidazopyridinyl group, and an imidazopyrimidinyl group; 
     Q 33  to Q 35  may be each independently selected from a hydrogen, a C 1 -C 20  alkyl group, a C 1 -C 20  alkoxy group, a phenyl group, a naphthyl group, an anthracenyl group, a pyrenyl group, a phenanthrenyl group, a fluorenyl group, a chrysenyl group, a carbazolyl group, a benzocarbazolyl group, a dibenzocarbazolyl group, a dibenzofuranyl group, a dibenzothiophenyl group, a pyridinyl group, a pyrimidinyl group, a triazinyl group, a quinolinyl group, an isoquinolinyl group, a quinazolinyl group, and a quinoxalinyl group; and 
     e1 may be an integer of 1 to 5; 
     e2 may be an integer of 1 to 7; 
     e3 may be an integer of 1 to 3; 
     e4 may be an integer of 1 to 4; 
     e5 may be an integer of 1 or 2; 
     e6 may be an integer of 1 to 6, and 
     * indicates a binding site to a neighboring atom. 
     According to another embodiment, R 1  and R 5  in Formula 1 may be each independently selected from 
     a hydrogen, a deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, an amino group, an amidino group, a hydrazine group, a hydrazone group, a carboxylic acid or a salt thereof, a sulfonic acid group or a salt thereof, a phosphoric acid group or a salt thereof, a C 1 -C 20  alkyl group, and a C 1 -C 20  alkoxy group; 
     a C 1 -C 20  alkyl group and a C 1 -C 20  alkoxy group, each substituted with at least one group selected from a deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, an amino group, an amidino group, a hydrazine group, a hydrazone group, a carboxylic acid or a salt thereof, a sulfonic acid group or a salt thereof, and a phosphoric acid group or a salt thereof; and 
     Formulae 5-1 to 5-91 below; 
     R 11  and R 12  may be each independently selected from 
     a C 1 -C 20  alkyl group and a C 1 -C 20  alkoxy group; 
     a C 1 -C 20  alkyl group and a C 1 -C 20  alkoxy group, each substituted with at least one group selected from a deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, an amino group, an amidino group, a hydrazine group, a hydrazone group, a carboxylic acid or a salt thereof, a sulfonic acid group or a salt thereof, and a phosphoric acid group or a salt thereof; and 
     Formulae 5-1 to 5-91 below: 
     
       
         
         
             
             
         
       
       
         
         
             
             
         
       
       
         
         
             
             
         
       
       
         
         
             
             
         
       
       
         
         
             
             
         
       
       
         
         
             
             
         
       
       
         
         
             
             
         
       
       
         
         
             
             
         
       
       
         
         
             
             
         
       
       
         
         
             
             
         
       
       
         
         
             
             
         
       
       
         
         
             
             
         
       
       
         
         
             
             
         
       
     
     wherein in Formulae 5-1 to 5-91, 
     * indicates a binding site to a neighboring atom. 
     b1 in Formula 1 indicates the number of R 1 , and may be an integer of 1 to 5, for example, an integer of 1 to 3. b1 may be 1 or 2, or 1. When b1 is 2 or more, groups R 1  may be identical or different. b2 to b8, b11, and b12 may be understood by referring to the description provided in connection with b1. 
     For example, the condensed cyclic compound may be represented by Formula 1A below: 
     
       
         
         
             
             
         
       
     
     L 5 , L 7 , a5, a7, R 1 , R 2 , R 3 , R 4 , R 5 , R 7 , R 11 , R 12 , b5, and b7 in Formula 1A may be understood by referring to the description provided herein. 
     For example, in Formula 1A, 
     L 5  and L 7  may be each independently selected from 
     a phenylene group, a naphthylene group, a fluorenylene group, a spiro-fluorenylene group, a benzofluorenylene group, a dibenzofluorenylene group, a phenalenylene group, a phenanthrenylene group, an anthracenylene group, a fluoranthenylene group, a triphenylenylene group, a pirenylene group, a chrisenylene group, a picenylene group, a pyridinylene group, a pyrazinylene group, a pyrimidinylene group, a pyridazinylene group, a quinolinylene group, an isoquinolinylene group, a benzoquinolinylene group, a quinoxalinylene group, a quinazolinylene group, a carbazolylene group, a phenanthridinylene group, a phenanthrolinylene group, a benzoimidazolylene group, a benzofuranylene group, a benzothiophenylene group, an isobenzothiazolylene group, a benzooxazolylene group, an isobenzooxazolylene group, a triazolylene group, an oxadiazolylene group, a triazinylene group, a dibenzofuranylene group, a dibenzothiophenylene group, a benzocarbazolylene group, a dibenzocarbazolylene group, an imidazopyridinylene group, and an imidazopyrimidinylene group; 
     a phenylene group, a naphthylene group, a fluorenylene group, a spiro-fluorenylene group, a benzofluorenylene group, a dibenzofluorenylene group, a phenalenylene group, a phenanthrenylene group, an anthracenylene group, a fluoranthenylene group, a triphenylenylene group, a pirenylene group, a chrisenylene group, a picenylene group, a pyridinylene group, a pyrazinylene group, a pyrimidinylene group, a pyridazinylene group, a quinolinylene group, an isoquinolinylene group, a benzoquinolinylene group, a quinoxalinylene group, a quinazolinylene group, a carbazolylene group, a phenanthridinylene group, a phenanthrolinylene group, a benzoimidazolylene group, a benzofuranylene group, a benzothiophenylene group, an isobenzothiazolylene group, a benzooxazolylene group, an isobenzooxazolylene group, a triazolylene group, an oxadiazolylene group, a triazinylene group, a dibenzofuranylene group, a dibenzothiophenylene group, a benzocarbazolylene group, a dibenzocarbazolylene group, an imidazopyridinylene group and an imidazopyrimidinylene group, each substituted with at least one group selected from a deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, an amino group, an amidino group, a hydrazine group, a hydrazone group, a carboxylic acid or a salt thereof, a sulfonic acid group or a salt thereof, a phosphoric acid group or a salt thereof, a C 1 -C 20  alkyl group, a C 1 -C 20  alkoxy group, a phenyl group, a naphthyl group, a fluorenyl group, a spiro-fluorenyl group, a benzofluorenyl group, a dibenzofluorenyl group, a phenalenyl group, a phenanthrenyl group, an anthracenyl group, a fluoranthenyl group, a triphenylenyl group, a pyrenyl group, a chrysenyl group, a pycenyl group, a pyridinyl group, a pyrazinyl group, a pyrimidinyl group, a pyridazinyl group, a quinolinyl group, an isoquinolinyl group, a benzoquinolinyl group, a quinoxalinyl group, a quinazolinyl group, a carbazolyl group, a phenanthridinyl group, a phenanthrolinyl group, a benzoimidazolyl group, a benzofuranyl group, a benzothiophenyl group, an isobenzothiazolyl group, a benzooxazolyl group, an isobenzooxazolyl group, a triazolyl group, an oxadiazolyl group, a triazinyl group, a dibenzofuranyl group, a dibenzothiophenyl group, a benzocarbazolyl group, a dibenzocarbazolyl group, an imidazopyridinyl group, and an imidazopyrimidinyl group; 
     a5 and a7 are each independently 0, 1, or 2; 
     R 1 , R 2 , R 3 , and R 4  may be each independently selected from 
     a hydrogen, a deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, an amino group, an amidino group, a hydrazine group, a hydrazone group, a carboxylic acid or a salt thereof, a sulfonic acid group or a salt thereof, a phosphoric acid group or a salt thereof, a C 1 -C 20  alkyl group, and a C 1 -C 20  alkoxy group; 
     a C 1 -C 20  alkyl group and a C 1 -C 20  alkoxy group, each substituted with at least one group selected from a deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, an amino group, an amidino group, a hydrazine group, a hydrazone group, a carboxylic acid or a salt thereof, a sulfonic acid group or a salt thereof, and a phosphoric acid group or a salt thereof; 
     a phenyl group, a naphthyl group, a fluorenyl group, a spiro-fluorenyl group, a benzofluorenyl group, a dibenzofluorenyl group, a phenalenyl group, a phenanthrenyl group, an anthracenyl group, a fluoranthenyl group, a triphenylenyl group, a pyrenyl group, a chrysenyl group, a pycenyl group, a pyridinyl group, a pyrazinyl group, a pyrimidinyl group, a pyridazinyl group, a quinolinyl group, an isoquinolinyl group, a benzoquinolinyl group, a quinoxalinyl group, a quinazolinyl group, a carbazolyl group, a phenanthridinyl group, a phenanthrolinyl group, a benzoimidazolyl group, a benzofuranyl group, a benzothiophenyl group, an isobenzothiazolyl group, a benzooxazolyl group, an isobenzooxazolyl group, a triazolyl group, an oxadiazolyl group, a triazinyl group, a dibenzofuranyl group, a dibenzothiophenyl group, a benzocarbazolyl group, a dibenzocarbazolyl group, an imidazopyridinyl group, an imidazopyrimidinyl group, a benzofurocarbazolyl group, and a benzothiolocarbazolyl group; and 
     a phenyl group, a naphthyl group, a fluorenyl group, a spiro-fluorenyl group, a benzofluorenyl group, a dibenzofluorenyl group, a phenalenyl group, a phenanthrenyl group, an anthracenyl group, a fluoranthenyl group, a triphenylenyl group, a pyrenyl group, a chrysenyl group, a pycenyl group, a pyridinyl group, a pyrazinyl group, a pyrimidinyl group, a pyridazinyl group, a quinolinyl group, an isoquinolinyl group, a benzoquinolinyl group, a quinoxalinyl group, a quinazolinyl group, a carbazolyl group, a phenanthridinyl group, a phenanthrolinyl group, a benzoimidazolyl group, a benzofuranyl group, a benzothiophenyl group, an isobenzothiazolyl group, a benzooxazolyl group, an isobenzooxazolyl group, a triazolyl group, an oxadiazolyl group, a triazinyl group, a dibenzofuranyl group, a dibenzothiophenyl group, a benzocarbazolyl group, a dibenzocarbazolyl group, an imidazopyridinyl group, an imidazopyrimidinyl group, a benzofurocarbazolyl group, and a benzothiolocarbazolyl group, each substituted with at least one group selected from a deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, an amino group, an amidino group, a hydrazine group, a hydrazone group, a carboxylic acid or a salt thereof, a sulfonic acid group or a salt thereof, a phosphoric acid group or a salt thereof, a C 1 -C 20  alkyl group, a C 1 -C 20  alkoxy group, and —Si(Q 33 )(Q 34 )(Q 35 ), a phenyl group, a naphthyl group, a fluorenyl group, a spiro-fluorenyl group, a benzofluorenyl group, a dibenzofluorenyl group, a phenalenyl group, a phenanthrenyl group, an anthracenyl group, a fluoranthenyl group, a triphenylenyl group, a pyrenyl group, a chrysenyl group, a pycenyl group, a pyridinyl group, a pyrazinyl group, a pyrimidinyl group, a pyridazinyl group, a quinolinyl group, an isoquinolinyl group, a benzoquinolinyl group, a quinoxalinyl group, a quinazolinyl group, a carbazolyl group, a phenanthridinyl group, a phenanthrolinyl group, a benzoimidazolyl group, a benzofuranyl group, a benzothiophenyl group, an isobenzothiazolyl group, a benzooxazolyl group, an isobenzooxazolyl group, a triazolyl group, an oxadiazolyl group, a triazinyl group, a dibenzofuranyl group, a dibenzothio group, a phenyl group, a benzocarbazolyl group, a dibenzocarbazolyl group, an imidazopyridinyl group, and an imidazopyrimidinyl group; 
     R 5  and R 7  may be each independently selected from 
     a phenyl group, a naphthyl group, a fluorenyl group, a spiro-fluorenyl group, a benzofluorenyl group, a dibenzofluorenyl group, a phenalenyl group, a phenanthrenyl group, an anthracenyl group, a fluoranthenyl group, a triphenylenyl group, a pyrenyl group, a chrysenyl group, a pycenyl group, a pyridinyl group, a pyrazinyl group, a pyrimidinyl group, a pyridazinyl group, a quinolinyl group, an isoquinolinyl group, a benzoquinolinyl group, a quinoxalinyl group, a quinazolinyl group, a carbazolyl group, a phenanthridinyl group, a phenanthrolinyl group, a benzoimidazolyl group, a benzofuranyl group, a benzothiophenyl group, an isobenzothiazolyl group, a benzooxazolyl group, an isobenzooxazolyl group, a triazolyl group, an oxadiazolyl group, a triazinyl group, a dibenzofuranyl group, a dibenzothiophenyl group, a benzocarbazolyl group, a dibenzocarbazolyl group, an imidazopyridinyl group, an imidazopyrimidinyl group, a benzofurocarbazolyl group, and a benzothiolocarbazolyl group; and 
     a phenyl group, a naphthyl group, a fluorenyl group, a spiro-fluorenyl group, a benzofluorenyl group, a dibenzofluorenyl group, a phenalenyl group, a phenanthrenyl group, an anthracenyl group, a fluoranthenyl group, a triphenylenyl group, a pyrenyl group, a chrysenyl group, a pycenyl group, a pyridinyl group, a pyrazinyl group, a pyrimidinyl group, a pyridazinyl group, a quinolinyl group, an isoquinolinyl group, a benzoquinolinyl group, a quinoxalinyl group, a quinazolinyl group, a carbazolyl group, a phenanthridinyl group, a phenanthrolinyl group, a benzoimidazolyl group, a benzofuranyl group, a benzothiophenyl group, an isobenzothiazolyl group, a benzooxazolyl group, an isobenzooxazolyl group, a triazolyl group, an oxadiazolyl group, a triazinyl group, a dibenzofuranyl group, a dibenzothiophenyl group, a benzocarbazolyl group, a dibenzocarbazolyl group, an imidazopyridinyl group, an imidazopyrimidinyl group, a benzofurocarbazolyl group, and a benzothiolocarbazolyl group, each substituted with at least one group selected from a deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, an amino group, an amidino group, a hydrazine group, a hydrazone group, a carboxylic acid or a salt thereof, a sulfonic acid group or a salt thereof, a phosphoric acid group or a salt thereof, a C 1 -C 20  alkyl group, a C 1 -C 20  alkoxy group, and —Si(Q 33 )(Q 34 )(Q 35 ), a phenyl group, a naphthyl group, a fluorenyl group, a spiro-fluorenyl group, a benzofluorenyl group, a dibenzofluorenyl group, a phenalenyl group, a phenanthrenyl group, an anthracenyl group, a fluoranthenyl group, a triphenylenyl group, a pyrenyl group, a chrysenyl group, a pycenyl group, a pyridinyl group, a pyrazinyl group, a pyrimidinyl group, a pyridazinyl group, a quinolinyl group, an isoquinolinyl group, a benzoquinolinyl group, a quinoxalinyl group, a quinazolinyl group, a carbazolyl group, a phenanthridinyl group, a phenanthrolinyl group, a benzoimidazolyl group, a benzofuranyl group, a benzothiophenyl group, an isobenzothiazolyl group, a benzooxazolyl group, an isobenzooxazolyl group, a triazolyl group, an oxadiazolyl group, a triazinyl group, a dibenzofuranyl group, a dibenzothio group, a phenyl group, a benzocarbazolyl group, a dibenzocarbazolyl group, an imidazopyridinyl group, and an imidazopyrimidinyl group; 
     R 11  and R 12  may be each independently selected from 
     a C 1 -C 20  alkyl group and a C 1 -C 20  alkoxy group; 
     a C 1 -C 20  alkyl group and a C 1 -C 20  alkoxy group, each substituted with at least one group selected from a deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, an amino group, an amidino group, a hydrazine group, a hydrazone group, a carboxylic acid or a salt thereof, a sulfonic acid group or a salt thereof, and a phosphoric acid group or a salt thereof; 
     a phenyl group, a naphthyl group, a fluorenyl group, a spiro-fluorenyl group, a benzofluorenyl group, a dibenzofluorenyl group, a phenalenyl group, a phenanthrenyl group, an anthracenyl group, a fluoranthenyl group, a triphenylenyl group, a pyrenyl group, a chrysenyl group, a pycenyl group, a pyridinyl group, a pyrazinyl group, a pyrimidinyl group, a pyridazinyl group, a quinolinyl group, an isoquinolinyl group, a benzoquinolinyl group, a quinoxalinyl group, a quinazolinyl group, a carbazolyl group, a phenanthridinyl group, a phenanthrolinyl group, a benzoimidazolyl group, a benzofuranyl group, a benzothiophenyl group, an isobenzothiazolyl group, a benzooxazolyl group, an isobenzooxazolyl group, a triazolyl group, an oxadiazolyl group, a triazinyl group, a dibenzofuranyl group, a dibenzothiophenyl group, a benzocarbazolyl group, a dibenzocarbazolyl group, an imidazopyridinyl group, an imidazopyrimidinyl group, a benzofurocarbazolyl group, and a benzothiolocarbazolyl group; and 
     a phenyl group, a naphthyl group, a fluorenyl group, a spiro-fluorenyl group, a benzofluorenyl group, a dibenzofluorenyl group, a phenalenyl group, a phenanthrenyl group, an anthracenyl group, a fluoranthenyl group, a triphenylenyl group, a pyrenyl group, a chrysenyl group, a pycenyl group, a pyridinyl group, a pyrazinyl group, a pyrimidinyl group, a pyridazinyl group, a quinolinyl group, an isoquinolinyl group, a benzoquinolinyl group, a quinoxalinyl group, a quinazolinyl group, a carbazolyl group, a phenanthridinyl group, a phenanthrolinyl group, a benzoimidazolyl group, a benzofuranyl group, a benzothiophenyl group, an isobenzothiazolyl group, a benzooxazolyl group, an isobenzooxazolyl group, a triazolyl group, an oxadiazolyl group, a triazinyl group, a dibenzofuranyl group, a dibenzothiophenyl group, a benzocarbazolyl group, a dibenzocarbazolyl group, an imidazopyridinyl group, an imidazopyrimidinyl group, a benzofurocarbazolyl group, and a benzothiolocarbazolyl group, each substituted with at least one group selected from a deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, an amino group, an amidino group, a hydrazine group, a hydrazone group, a carboxylic acid or a salt thereof, a sulfonic acid group or a salt thereof, a phosphoric acid group or a salt thereof, a C 1 -C 20  alkyl group, a C 1 -C 20  alkoxy group, and —Si(Q 33 )(Q 34 )(Q 35 ), a phenyl group, a naphthyl group, a fluorenyl group, a spiro-fluorenyl group, a benzofluorenyl group, a dibenzofluorenyl group, a phenalenyl group, a phenanthrenyl group, an anthracenyl group, a fluoranthenyl group, a triphenylenyl group, a pyrenyl group, a chrysenyl group, a pycenyl group, a pyridinyl group, a pyrazinyl group, a pyrimidinyl group, a pyridazinyl group, a quinolinyl group, an isoquinolinyl group, a benzoquinolinyl group, a quinoxalinyl group, a quinazolinyl group, a carbazolyl group, a phenanthridinyl group, a phenanthrolinyl group, a benzoimidazolyl group, a benzofuranyl group, a benzothiophenyl group, an isobenzothiazolyl group, a benzooxazolyl group, an isobenzooxazolyl group, a triazolyl group, an oxadiazolyl group, a triazinyl group, a dibenzofuranyl group, a dibenzothio group, a phenyl group, a benzocarbazolyl group, a dibenzocarbazolyl group, an imidazopyridinyl group, and an imidazopyrimidinyl group; 
     b5 and b7 are each independently 1 or 2, 
     wherein Q 33  to Q 35  may be each independently selected from a hydrogen, a C 1 -C 20  alkyl group, a C 1 -C 20  alkoxy group, a phenyl group, a naphthyl group, an anthracenyl group, a pyrenyl group, a phenanthrenyl group, a fluorenyl group, a chrysenyl group, a carbazolyl group, a benzocarbazolyl group, a dibenzocarbazolyl group, a dibenzofuranyl group, a dibenzothiophenyl group, a pyridinyl group, a pyrimidinyl group, a triazinyl group, a quinolinyl group, an isoquinolinyl group, a quinazolinyl group, and a quinoxalinyl group, but they are not limited thereto. 
     According to another embodiment, the condensed cyclic compound may be represented by Formula 1A, and at least one of R 5  and R 7  may be selected from 
     a carbazolyl group, a dibenzofuranyl group, a dibenzothiophenyl group, a benzocarbazolyl group, a dibenzocarbazolyl group, a benzofurocarbazolyl group, and a benzothiolocarbazolyl group; and 
     a carbazolyl group, a dibenzofuranyl group, a dibenzothiophenyl group, a benzocarbazolyl group, a dibenzocarbazolyl group, a benzofurocarbazolyl group, and a benzothiolocarbazolyl group, each substituted with at least one group selected from a deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, an amino group, an amidino group, a hydrazine group, a hydrazone group, a carboxylic acid or a salt thereof, a sulfonic acid group or a salt thereof, a phosphoric acid group or a salt thereof, a C 1 -C 20  alkyl group, a C 1 -C 20  alkoxy group, a phenyl group, a naphthyl group, a fluorenyl group, a spiro-fluorenyl group, a benzofluorenyl group, a dibenzofluorenyl group, a phenalenyl group, a phenanthrenyl group, an anthracenyl group, a fluoranthenyl group, a triphenylenyl group, a pyrenyl group, a chrysenyl group, a pycenyl group, a pyridinyl group, a pyrazinyl group, a pyrimidinyl group, a pyridazinyl group, a quinolinyl group, an isoquinolinyl group, a benzoquinolinyl group, a quinoxalinyl group, a quinazolinyl group, a carbazolyl group, a phenanthridinyl group, a phenanthrolinyl group, a benzoimidazolyl group, a benzofuranyl group, a benzothiophenyl group, an isobenzothiazolyl group, a benzooxazolyl group, an isobenzooxazolyl group, a triazolyl group, an oxadiazolyl group, a triazinyl group, a dibenzofuranyl group, a dibenzothiophenyl group, a benzocarbazolyl group, a dibenzocarbazolyl group, an imidazopyridinyl group, and an imidazopyrimidinyl group, but they are not limited thereto. 
     According to another embodiment, the condensed cyclic compound may be represented by Formula 1A, and in Formula 1A, 
     L 5  and L 7  may be each independently selected from Formulae 2-1 to 2-33 (for example, Formulae 3-1 to 3-38); 
     a5 and a7 may be each independently 0, 1, or 2; 
     R 1 , R 2 , R 3 , and R 4  may be each independently selected from a hydrogen, a deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, an amino group, an amidino group, a hydrazine group, a hydrazone group, a carboxylic acid or a salt thereof, a sulfonic acid group or a salt thereof, a phosphoric acid group or a salt thereof, a C 1 -C 20  alkyl group, a C 1 -C 20  alkoxy group, a phenyl group, a naphthyl group, an anthracenyl group, a dimethylfluorenyl group, a diphenylfluorenyl group, and a phenylcarbazolyl group; 
     R 5  and R 7  are each independently selected from Formulae 4-1 to 4-60 (for example, Formulae 5-1 to 5-91); 
     R 11  and R 12  may be each independently selected from a C 1 -C 20  alkyl group, a C 1 -C 20  alkoxy group, a phenyl group, a naphthyl group, an anthracenyl group, a dimethylfluorenyl group, a diphenylfluorenyl group, and a phenylcarbazolyl group; and 
     b5 and b7 may be each independently 1 or 2, but are not limited thereto. 
     The condensed cyclic compound may be one of Compounds 1 to 295 below, but is not limited thereto: 
     
       
         
         
             
             
         
       
       
         
         
             
             
         
       
       
         
         
             
             
         
       
       
         
         
             
             
         
       
       
         
         
             
             
         
       
       
         
         
             
             
         
       
       
         
         
             
             
         
       
       
         
         
             
             
         
       
       
         
         
             
             
         
       
       
         
         
             
             
         
       
       
         
         
             
             
         
       
       
         
         
             
             
         
       
       
         
         
             
             
         
       
       
         
         
             
             
         
       
       
         
         
             
             
         
       
       
         
         
             
             
         
       
       
         
         
             
             
         
       
       
         
         
             
             
         
       
       
         
         
             
             
         
       
       
         
         
             
             
         
       
       
         
         
             
             
         
       
       
         
         
             
             
         
       
       
         
         
             
             
         
       
       
         
         
             
             
         
       
       
         
         
             
             
         
       
       
         
         
             
             
         
       
       
         
         
             
             
         
       
       
         
         
             
             
         
       
       
         
         
             
             
         
       
       
         
         
             
             
         
       
       
         
         
             
             
         
       
       
         
         
             
             
         
       
       
         
         
             
             
         
       
       
         
         
             
             
         
       
       
         
         
             
             
         
       
       
         
         
             
             
         
       
       
         
         
             
             
         
       
       
         
         
             
             
         
       
       
         
         
             
             
         
       
       
         
         
             
             
         
       
       
         
         
             
             
         
       
       
         
         
             
             
         
       
       
         
         
             
             
         
       
       
         
         
             
             
         
       
       
         
         
             
             
         
       
       
         
         
             
             
         
       
       
         
         
             
             
         
       
       
         
         
             
             
         
       
       
         
         
             
             
         
       
       
         
         
             
             
         
       
       
         
         
             
             
         
       
       
         
         
             
             
         
       
       
         
         
             
             
         
       
       
         
         
             
             
         
       
       
         
         
             
             
         
       
       
         
         
             
             
         
       
       
         
         
             
             
         
       
       
         
         
             
             
         
       
       
         
         
             
             
         
       
       
         
         
             
             
         
       
       
         
         
             
             
         
       
       
         
         
             
             
         
       
       
         
         
             
             
         
       
       
         
         
             
             
         
       
       
         
         
             
             
         
       
       
         
         
             
             
         
       
       
         
         
             
             
         
       
       
         
         
             
             
         
       
       
         
         
             
             
         
       
       
         
         
             
             
         
       
       
         
         
             
             
         
       
       
         
         
             
             
         
       
       
         
         
             
             
         
       
       
         
         
             
             
         
       
       
         
         
             
             
         
       
       
         
         
             
             
         
       
       
         
         
             
             
         
       
       
         
         
             
             
         
       
       
         
         
             
             
         
       
       
         
         
             
             
         
       
       
         
         
             
             
         
       
       
         
         
             
             
         
       
       
         
         
             
             
         
       
       
         
         
             
             
         
       
       
         
         
             
             
         
       
       
         
         
             
             
         
       
       
         
         
             
             
         
       
       
         
         
             
             
         
       
       
         
         
             
             
         
       
       
         
         
             
             
         
       
       
         
         
             
             
         
       
       
         
         
             
             
         
       
       
         
         
             
             
         
       
       
         
         
             
             
         
       
       
         
         
             
             
         
       
       
         
         
             
             
         
       
     
     The highest occupied molecular orbital (HOMO) and lowest unoccupied molecular orbital (LUMO) of the condensed cyclic compound represented by Formula 1 may be controlled, and accordingly, an organic light-emitting device including the condensed cyclic compound may achieve high efficiency, long lifespan, and high brightness. 
     Synthesis methods of the condensed cyclic compound represented by Formula 1 are known to one of ordinary skill in the art by referring to Synthesis Examples provided below. 
     The condensed cyclic compound represented by Formula 1 is suitable for use in an organic layer of an organic light-emitting device, for example, for use as a host in an emission layer of the organic layer. Thus, another aspect provides an organic light-emitting device that includes: 
     a first electrode; 
     a second electrode; and 
     an organic layer disposed between the first electrode and the second electrode, 
     wherein the organic layer includes an emission layer and at least one of the condensed cyclic compound represented by Formula 1. 
     The organic light-emitting device may have, due to the inclusion of an organic layer including the condensed cyclic compound represented by Formula 1, low driving voltage, high efficiency, high brightness, and long lifespan. 
     The condensed cyclic compound of Formula 1 may be used between a pair of electrodes of an organic light-emitting device. For example, the condensed cyclic compound may be included in at least one layer selected from 
     i) the emission layer, 
     ii) a hole transport region (including, for example, at least one of a hole injection layer, a hole transport layer, a buffer layer, and an electron blocking layer) that is disposed between the first electrode and the emission layer, and 
     iii) an electron transport region (including, for example, at least one layer selected from a hole blocking layer, an electron transport layer, and an electron injection layer) that is disposed between the emission layer and the second electrode. 
     For example, the condensed cyclic compound represented by Formula 1 may be included in the emission layer. In this regard, the emission layer may further include a dopant, and the condensed cyclic compound included in the emission layer may act as a host. The emission layer may be a green emission layer emitting green light, and the dopant may be a phosphorescent dopant. 
     The expression “(an organic layer) includes at least one condensed cyclic compound” as used herein may include a case in which “(an organic layer) includes one condensed cyclic compound of Formula 1 and a case in which (an organic layer) includes two or more different condensed cyclic compounds of Formula 1. 
     For example, the organic layer may include, as the condensed cyclic compound, only Compound 1. In this regard, Compound 1 may exist in an emission layer of the organic light-emitting device. In another embodiment, the organic layer may include, as the condensed cyclic compound, Compound 1 and Compound 2. In this regard, Compound 1 and Compound 2 may be situated in either an identical layer (for example, Compound 1 and Compound 2 all may exist in an emission layer), or different layers. 
     The first electrode may be an anode, which is a hole injection electrode, and the second electrode may be a cathode, which is an electron injection electrode, or the first electrode may be a cathode, which is an electron injection electrode, or the second electrode may be an anode, which is a hole injection electrode. 
     For example, the first electrode is an anode, and the second electrode is a cathode, and the organic layer includes 
     i) a hole transport region that is disposed between the first electrode and the emission layer and includes at least one of a hole injection layer, a hole transport layer, and an electron blocking layer, and 
     ii) an electron transport region that is disposed between the emission layer and the second electrode and includes at least one group selected from a hole blocking layer, an electron transport layer, and an electron injection layer. 
     The term “organic layer” as used herein refers to a single layer and/or a plurality of layers disposed between the first electrode and the second electrode of an organic light-emitting device. The “organic layer” may include, in addition to an organic compound, an organometallic complex including metal. 
       FIG. 1  is a schematic view of an organic light-emitting device  10  according to an embodiment. Hereinafter, the structure of an organic light-emitting device according to an embodiment and a method of manufacturing an organic light-emitting device according to an embodiment will be described in connection with  FIG. 1 . The organic light-emitting device  10  includes a first electrode  11 , an organic layer  15 , and a second electrode  19 , which are sequentially stacked. 
     In  FIG. 1 , a substrate may be additionally disposed under the first electrode  11  or above the second electrode  19 . For use as the substrate, any substrate that is used in general organic light-emitting devices may be used, and the substrate may be a glass substrate or transparent plastic substrate, each with excellent mechanical strength, thermal stability, transparency, surface smoothness, ease of handling, and water repellency. 
     The first electrode  11  may be formed by depositing or sputtering a material for forming the first electrode on the substrate. The first electrode  11  may be an anode. The material for the first electrode  11  may be selected from materials with a high work function to facilitate the injection of holes. The first electrode  13  may be a reflective electrode or a transmissive electrode. The material for the first electrode  11  may be an indium tin oxide (ITO), indium zinc oxide (IZO), tin oxide (SnO 2 ), or zinc oxide (ZnO). According to another embodiment, the material for the first electrode  11  may be metal, such as magnesium (Mg), aluminum (Al), aluminum-lithium (Al—Li), calcium (Ca), magnesium-indium (Mg—In), or magnesium-silver (Mg—Ag). 
     The first electrode  11  may have a single-layer structure or a multi-layer structure including two or more layers. For example, the first electrode  11  may have a three-layered structure of ITO/Ag/ITO, but the structure of the first electrode  110  is not limited thereto. 
     An organic layer  15  is disposed on the first electrode  11 . 
     The organic layer  15  may include a hole transport region, an emission layer, and an electron transport region. 
     The hole transport region may be disposed between the first electrode  11  and the emission layer. 
     The hole transport region may include at least one of a hole injection layer, a hole transport layer, an electron blocking layer, and a buffer layer. 
     The hole transport region may include only either a hole injection layer or a hole transport layer. According to another embodiment, the hole transport region may have a structure of hole injection layer/hole transport layer or hole injection layer/hole transport layer/electron blocking layer, which are sequentially stacked in this stated order from the first electrode  11 . 
     When the hole injection layer (hole injection layer) includes a hole injection layer, the hole injection layer may be formed on the first electrode  11  by using any one of various methods known to one of ordinary skill in the art, for example, vacuum deposition, spin coating, casting, or Langmuir-Blodgett (LB) deposition. 
     When a hole injection layer is formed by vacuum deposition, the deposition conditions may vary according to a material that is used to form the hole injection layer, and the structure and thermal characteristics of the hole injection layer. For example, the deposition conditions may include a deposition temperature of about 100 to about 500° C., a vacuum pressure of about 10 −8  to about 10 −3  torr, and a deposition rate of about 0.01 to about 100 Angstroms per second (A/sec). However, the deposition conditions are not limited thereto. 
     When the hole injection layer is formed using spin coating, coating conditions may vary according to the material used to form the hole injection layer, and the structure and thermal properties of the hole injection layer. For example, a coating speed may be from about 2,000 revolutions per minute (rpm) to about 5,000 rpm, and a temperature at which a heat treatment is performed to remove a solvent after coating may be from about 80° C. to about 200° C. However, the coating conditions are not limited thereto. 
     Conditions for a hole transport layer and an electron blocking layer may be understood by referring to conditions for forming the hole injection layer. 
     The hole transport region may include at least one group selected from m-MTDATA, TDATA, 2-TNATA, NPB, β-NPB, TPD, Spiro-TPD, Spiro-NPB, α-NPB, TAPC, HMTPD, 4,4′,4″-tris(N-carbazolyl)triphenylamine (TCTA), polyaniline/dodecylbenzenesulfonic acid (Pani/DBSA), poly(3,4-ethylenedioxythiophene)/poly(4-styrenesulfonate) (PEDOT/PSS), polyaniline/camphor sulfonic acid (Pani/CSA), (polyaniline)/poly(4-styrenesulfonate) (PANI/PSS), a compound represented by Formula 201 below, and a compound represented by Formula 202 below: 
     
       
         
         
             
             
         
       
       
         
         
             
             
         
       
       
         
         
             
             
         
       
       
         
         
             
             
         
       
     
     Ar 101  to Ar 102  in Formula 201 may be each independently selected from 
     a phenylene group, a pentalenylene group, an indenylene group, a naphthylene group, an azulenylene group, a heptalenylene group, an acenaphthylene group, a fluorenylene group, a phenalenylene group, a phenanthrenylene group, an anthracenylene group, a fluoranthenylene group, a triphenylenylene group, a pyrenylene group, a chrysenylene group, a naphthacenylene group, a picenylene group, a perylenylene group, and a pentacenylene group; and 
     a phenylene group, a pentalenylene group, an indenylene group, a naphthylene group, an azulenylene group, a heptalenylene group, an acenaphthylene group, a fluorenylene group, a phenalenylene group, a phenanthrenylene group, an anthracenylene group, a fluoranthenylene group, a triphenylenylene group, a pyrenylene group, a chrysenylene group, a naphthacenylene group, a picenylene group, a perylenylene group, and a pentacenylene group, each substituted with at least one group selected from a deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, an amino group, an amidino group, a hydrazine group, a hydrazone group, a carboxylic acid or a salt thereof, a sulfonic acid or a salt thereof, a phosphoric acid or a salt thereof, a C 1 -C 60  alkyl group, a C 2 -C 60  alkenyl group, a C 2 -C 60  alkynyl group, a C 1 -C 10  alkoxy group, a C 3 -C 10  cycloalkyl group, a C 3 -C 10  cycloalkenyl group, a C 2 -C 10  heterocycloalkyl group, a C 2 -C 10  heterocycloalkenyl group, a C 6 -C 60  aryl group, a C 6 -C 60  aryloxy group, a C 6 -C 60  arythio group, a C 2 -C 60  heteroaryl group, a monovalent non-aromatic condensed polycyclic group, and a monovalent non-aromatic condensed heteropolycyclic group. 
     xa and xb in Formula 201 may be each independently an integer of 0 to 5, or 0, 1 or 2. For example, xa may be 1 and xb may be 0, but xa and xb are not limited thereto. 
     R 101  to R 108 , R 111  to R 119 , and R 121  to R 124  in Formulae 201 and 202 may be each independently selected from 
     a hydrogen, a deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, an amino group, an amidino group, a hydrazine group, a hydrazone group, a carboxylic acid or a salt thereof, a sulfonic acid or a salt thereof, a phosphoric acid or a salt thereof, a C 1 -C 10  alkyl group (for example, a methyl group, an ethyl group, a propyl group, a butyl group, a pentyl group, a hexyl group, and so on) and a C 1 -C 10  alkoxy group (for example, a methoxy group, an ethoxy group, a propoxy group, a butoxy group, a pentoxy group, and so on); 
     a C 1 -C 10  alkyl group and a C 1 -C 10  alkoxy group, each substituted with at least one group selected from a deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, an amino group, an amidino group, a hydrazine group, a hydrazone group, a carboxylic acid or a salt thereof, a sulfonic acid or a salt thereof, and a phosphoric acid or a salt thereof; 
     a phenyl group, a naphthyl group, an anthracenyl group, a fluorenyl group, and a pyrenyl group; and 
     a phenyl group, a naphthyl group, an anthracenyl group, a fluorenyl group, and a pyrenyl group, each substituted with at least one group selected from a deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, an amino group, an amidino group, a hydrazine group, a hydrazone group, a carboxylic acid or a salt thereof, a sulfonic acid or a salt thereof, a phosphoric acid or a salt thereof, a C 1 -C 10  alkyl group, and a C 1 -C 10  alkoxy group, but they are not limited thereto. 
     R 109  in Formula 201 may be selected from a phenyl group, a naphthyl group, an anthracenyl group and a pyridinyl group; and a phenyl group, a naphthyl group, an anthracenyl group and a pyridinyl group, each substituted with at least one group selected from a deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, an amino group, an amidino group, a hydrazine group, a hydrazone group, a carboxylic acid or a salt thereof, a sulfonic acid or a salt thereof, a phosphoric acid or a salt thereof, a C 1 -C 20  alkyl group, and a C 1 -C 20  alkoxy group. 
     According to an embodiment, the compound represented by Formula 201 may be represented by Formula 201A below, but is not limited thereto: 
     
       
         
         
             
             
         
       
     
     R 101 , R 111 , R 112 , and R 109  in Formula 201A may be understood by referring to the description provided herein. 
     For example, the compound represented by Formula 201, and the compound represented by Formula 202 may include compounds HT1 to HT20 illustrated below, but are not limited thereto. 
     
       
         
         
             
             
         
       
       
         
         
             
             
         
       
       
         
         
             
             
         
       
       
         
         
             
             
         
       
       
         
         
             
             
         
       
       
         
         
             
             
         
       
       
         
         
             
             
         
       
     
     A thickness of the hole transport region may be in a range of about 100 Angstroms (Å) to about 10,000 Å, for example, about 100 Å to about 1,000 Å. When the hole transport region includes both a hole injection layer and a hole transport layer, a thickness of the hole injection layer may be in a range of about 100 Å to about 10,000 Å, for example, about 100 Å to about 1,000 Å, and a thickness of the hole transport layer may be in a range of about 50 Å to about 2,000 Å, for example about 100 Å to about 1,500 Å. When the thicknesses of the hole transport region, the hole injection layer, and the hole transport layer are within these ranges, satisfactory hole transporting characteristics may be obtained without a substantial increase in driving voltage. 
     The hole transport region may further include, in addition to these materials, a charge-generation material for the improvement of conductive properties. The charge-generation material may be homogeneously or non-homogeneously dispersed in the hole transport region. 
     The charge-generation material may be, for example, a p-dopant. The p-dopant may be one of a quinone derivative, a metal oxide, and a cyano group-containing compound, but is not limited thereto. Non-limiting examples of the p-dopant are a quinone derivative, such as tetracyanoquinonedimethane (TCNQ) or 2,3,5,6-tetrafluoro-tetracyano-1,4-benzoquinonedimethane (F4-TCNQ); a metal oxide, such as a tungsten oxide or a molybdenium oxide; and a cyano group-containing compound, such as Compound HT-D1 below, but are not limited thereto. 
     
       
         
         
             
             
         
       
     
     The hole transport region may include a buffer layer. 
     Also, the buffer layer may compensate for an optical resonance distance according to a wavelength of light emitted from the emission layer, and thus, efficiency of a formed organic light-emitting device may be improved. 
     Then, an emission layer (emission layer) may be formed on the hole transport region by vacuum deposition, spin coating, casting, LB deposition, or the like. When the emission layer is formed by vacuum deposition or spin coating, the deposition or coating conditions may be similar to those applied to form the hole injection layer although the deposition or coating conditions may vary according to the material that is used to form the emission layer. 
     The emission layer may include a host and a dopant. The host may include at least one condensed cyclic compound represented by Formula 1. 
     The host may further include, in addition to the condensed cyclic compound represented by Formula 1, at least one of TPBi, TBADN, AND (also referred to as “DNA”), CBP, CDBP, and TCP. 
     
       
         
         
             
             
         
       
       
         
         
             
             
         
       
     
     When the organic light-emitting device is a full color organic light-emitting device, the emission layer may be patterned into a red emission layer, a green emission layer, and a blue emission layer. According to another embodiment, due to a stack structure including a red emission layer, a green emission layer, and/or a blue emission layer, the emission layer may emit white light. A host in the red emission layer, the green emission layer, and the blue emission layer may include the condensed cyclic compound represented by Formula 1. According to an embodiment, the host in the green emission layer may include the condensed cyclic compound represented by Formula 1. 
     A dopant in the emission layer may be a fluorescent dopant that emits light according to a fluorescent emission mechanism or a phosphorescent dopant that emits light according to a phosphorescent emission mechanism. 
     According to an embodiment, the emission layer may include a host including the condensed cyclic compound represented by Formula 1 and a phosphorescent dopant. The phosphorescent dopant may include an organometallic complex including a transition metal (for example, iridium (Ir), platinum (Pt), osmium (Os), or rhodium (Rh)). 
     The phosphorescent dopant may include an organometallic complex represented by Formula 81 below: 
     
       
         
         
             
             
         
       
     
     wherein in Formula 81, 
     M may be selected from iridium (Ir), platinum (Pt), osmium (Os), titanium (Ti), zirconium (Zr), hafnium (Hf), euroform (Eu), terbium (Tb), and tolium (Tm); 
     Y 1  to Y 4  may be each independently carbon (C) or nitrogen (N); 
     CY 1  and CY 2  may be each independently selected from a benzene, a naphthalene, a fluorene, a spiro-fluorene, an indene, a pyrrole, a thiophene, a furan, an imidazole, a pyrazole, a thiazole, an isothiazole, an oxazole, an isooxazole, a pyridine, a pyrazine, a pyrimidine, a pyridazine, a quinoline, a isoquinoline, a benzoquinoline, a quinoxaline, a quinazoline, a carbazole, a benzoimidazole, a benzofuran, a benzothiophene, a isobenzothiophene, a benzooxazole, a isobenzooxazole, a triazole, a tetrazole, a oxadiazole, a triazine, a dibenzofuran, and a dibenzothiophene, and CY 1  and CY 2  may be optionally linked to each other by a single bond or an organic linking group; 
     R 81  and R 82  may be each independently selected from a hydrogen, a deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, an amino group, an amidino group, a hydrazine group, a hydrazone group, a carboxylic acid or a salt thereof, a sulfonic acid group or a salt thereof, a phosphoric acid group or a salt thereof, —SF 5 , a substituted or unsubstituted C 1 -C 60  alkyl group, a substituted or unsubstituted C 2 -C 60  alkenyl group, a substituted or unsubstituted C 2 -C 60  alkynyl group, a substituted or unsubstituted C 1 -C 60  alkoxy group, a substituted or unsubstituted C 3 -C 10  cycloalkyl group, a substituted or unsubstituted C 2 -C 10  heterocycloalkyl group, a substituted or unsubstituted C 3 -C 10  cycloalkenyl group, a substituted or unsubstituted C 2 -C 10  heterocycloalkenyl group, a substituted or unsubstituted C 6 -C 60  aryl group, a substituted or unsubstituted C 6 -C 60  aryloxy group, a substituted or unsubstituted C 6 -C 60  arythio group, a substituted or unsubstituted C 2 -C 60  heteroaryl group, a substituted or unsubstituted monovalent non-aromatic condensed polycyclic group, a substituted or unsubstituted monovalent non-aromatic condensed heteropolycyclic group, —N(Q 1 )(Q 2 ), —Si(Q 3 )(Q 4 )(Q 5 ), and —B(Q 6 )(Q 7 ); 
     a81 and a82 may be each independently an integer selected from 1 to 5; 
     n81 may be an integer selected from 0 to 4; 
     n82 may be 1, 2, or 3; 
     L 81  may be selected from a monovalent organic ligand, a divalent organic ligand, and a trivalent organic ligand. 
     In Formula 81, the bond between Y 1  and Y 2  and the bond between Y 3  and Y 4  may be each independently a single bond or a double bond. 
     R 81  to R 82  may be understood by referring to the description provided herein in connection with R 1 ; 
     The phosphorescent dopant may include at least one of Compounds PD1 to PD74 below, but is not limited thereto: 
     
       
         
         
             
             
         
       
       
         
         
             
             
         
       
       
         
         
             
             
         
       
       
         
         
             
             
         
       
       
         
         
             
             
         
       
       
         
         
             
             
         
       
       
         
         
             
             
         
       
       
         
         
             
             
         
       
       
         
         
             
             
         
       
       
         
         
             
             
         
       
       
         
         
             
             
         
       
       
         
         
             
             
         
       
       
         
         
             
             
         
       
       
         
         
             
             
         
       
     
     According to another embodiment, the phosphorescent dopant may include PtOEP or Compound PhGD illustrated below: 
     
       
         
         
             
             
         
       
     
     The fluorescent dopant may include at least one group selected from DPAVBi, BDAVBi, TBPe, DCM, DCJTB, Coumarin 6, and C545T. 
     
       
         
         
             
             
         
       
     
     When the emission layer includes a host and a dopant, an amount of the dopant may be in a range of about 0.01 to about 15 parts by weight based on 100 parts by weight of the host, but is not limited thereto. 
     A thickness of the emission layer may be in a range of about 100 Å to about 1,000 Å, for example, about 200 Å to about 600 Å. When the thickness of the emission layer is within this range, excellent light-emission characteristics may be obtained without a substantial increase in driving voltage. 
     Then, an electron transport region may be disposed on the emission layer. 
     The electron transport region may include at least one group selected from a hole blocking layer, an electron transport layer, and an electron injection layer. 
     For example, the electron transport region may have a structure of hole blocking layer/electron transport layer/electron injection layer or electron transport layer/electron injection layer, but the structure of the electron transport region is not limited thereto. The electron transport layer may have a single-layered structure or a multi-layer structure including two or more different materials. 
     Conditions for forming the hole blocking layer, electron transport layer, and electron injection layer of the electron transport region may be understood by referring to the conditions for forming the hole injection layer. 
     When the electron transport layer includes a hole blocking layer, the hole blocking layer may include, for example, at least one of BCP and Bphen, but a material included in the hole blocking layer is not limited thereto. 
     
       
         
         
             
             
         
       
     
     A thickness of the hole blocking layer may be in a range of about 20 Å to about 1,000 Å, for example, about 30 Å to about 300 Å. When the thickness of the hole blocking layer is within these ranges, the hole blocking layer may have excellent hole blocking characteristics without a substantial increase in driving voltage. 
     The electron transport layer may further include, in addition to the condensed cyclic compound represented by Formula 1, at least one group selected from BCP, Bphen, Alq 3 , Balq, TAZ, and NTAZ. 
     
       
         
         
             
             
         
       
     
     According to another embodiment, the electron transport layer may include at least one of ET1 and ET2, but are not limited thereto: 
     
       
         
         
             
             
         
       
     
     A thickness of the electron transport layer may be in a range of about 100 Å to about 1,000 Å, for example, about 150 Å to about 500 Å. When the thickness of the electron transport layer is within the range described above, the electron transport layer may have satisfactory electron transport characteristics without a substantial increase in driving voltage. 
     Also, the electron transport layer may further include, in addition to the materials described above, a metal-containing material. 
     The metal-containing material may include a Li complex. The Li complex may include, for example, Compound ET-D1 (lithium quinolate, LiQ) or ET-D2. 
     
       
         
         
             
             
         
       
     
     The electron transport region may include an electron injection layer (EIL) that allows electrons to be easily provided from a second electrode  19 . 
     The electron injection layer may include at least one group selected from, LiF, NaCl, CsF, Li 2 O, BaO, and LiQ. 
     A thickness of the electron injection layer may be in a range of about 1 Å to about 100 Å, for example, about 3 Å to about 90 Å. When the thickness of the electron injection layer is within the range described above, the electron injection layer may have satisfactory electron injection characteristics without a substantial increase in driving voltage. 
     The second electrode  19  is disposed on the organic layer  15 . The second electrode  19  may be a cathode. A material for forming the second electrode  19  may be metal, an alloy, an electrically conductive compound, and a combination thereof, which have a relatively low work function. For example, lithium (Li), magnesium (Mg), aluminum (Al), aluminum-lithium (Al—Li), calcium (Ca), magnesium-indium (Mg—In), or magnesium-silver (Mg—Ag) may be formed as the material for forming the second electrode  19 . To manufacture a top emission type light-emitting device, a transmissive electrode formed using ITO or IZO may be used as the second electrode  19 . 
     Hereinbefore, the organic light-emitting device has been described with reference to  FIG. 1 , but is not limited thereto. 
     A C 1 -C 60  alkyl group used herein refers to a linear or branched aliphatic hydrocarbon monovalent group having 1 to 60 carbon atoms. Detailed examples thereof are a methyl group, an ethyl group, a propyl group, an isobutyl group, a sec-butyl group, a tert-butyl group, a pentyl group, an iso-amyl group, and a hexyl group. A C 1 -C 60  alkylene group used herein refers to a divalent group having the same structure as the C 1 -C 60  alkyl group. 
     A C 1 -C 60  alkoxy group as used herein refers to a monovalent group represented by -OA 101  (wherein A 101  is the C 1 -C 60  alkyl group). Detailed examples thereof are a methoxy group, an ethoxy group, and an isopropyloxy group. 
     A C 2 -C 60  alkenyl group as used herein refers to a hydrocarbon group formed by substituting at least one carbon double bond in the middle or at the terminal of the C 2 -C 60  alkyl group. Detailed examples thereof are an ethenyl group, a propenyl group, and a butenyl group. A C 2 -C 60  alkenylene group used herein refers to a divalent group having the same structure as the C 2 -C 60  alkenyl group. 
     A C 2 -C 60  alkynyl group as used herein refers to a hydrocarbon group having at least one carbon triple bond in the middle or at the terminal of the C 2 -C 60  alkyl group. Detailed examples thereof are an ethynyl group, and a propynyl group. A C 2 -C 60  alkynylene group used herein refers to a divalent group having the same structure as the C 2 -C 60  alkynyl group. 
     A C 3 -C 10  cycloalkyl group as used herein refers to a monovalent hydrocarbon monocyclic group having 3 to 10 carbon atoms. Detailed examples thereof are a cyclopropyl group, a cyclobutyl group, a cyclopentyl group, a cyclohexyl group, and a cycloheptyl group. A C 3 -C 10  cycloalkylene group used herein refers to a divalent group having the same structure as the C 3 -C 10  cycloalkyl group. 
     A C 2 -C 10  heterocycloalkyl group as used herein refers to a monovalent monocyclic group having at least one hetero atom selected from N, O, P, and S as a ring-forming atom and 2 to 10 carbon atoms. Detailed examples thereof are a tetrahydrofuranyl group, and a tetrahydrothiophenyl group. A C 2 -C 10  heterocycloalkylene group used herein refers to a divalent group having the same structure as the C 2 -C 10  heterocycloalkyl group. 
     A C 3 -C 10  cycloalkenyl group as used herein refers to a monovalent monocyclic group that has 3 to 10 carbon atoms and at least one double bond in the ring thereof and does not have aromaticity. Detailed examples thereof are a cyclopentenyl group, a cyclohexenyl group, and a cycloheptenyl group. A C 3 -C 10  cycloalkenylene group used herein refers to a divalent group having the same structure as the C 3 -C 10  cycloalkenyl group. 
     A C 2 -C 10  heterocycloalkenyl group as used herein refers to a monovalent monocyclic group that has at least one heteroatom selected from N, O, P, and S as a ring-forming atom, 2 to 10 carbon atoms, and at least one double bond in its ring. Detailed examples of the C 2 -C 10  heterocycloalkenyl group are a 2,3-dihydrofuranyl group and a 2,3-dihydrothiophenyl group. A C 2 -C 10  heterocycloalkenylene group used herein refers to a divalent group having the same structure as the C 2 -C 10  heterocycloalkenyl group. 
     A C 6 -C 60  aryl group as used herein refers to a monovalent group having a carbocyclic aromatic system having 6 to 60 carbon atoms, and a C 6 -C 60  arylene group used herein refers to a divalent group having a carbocyclic aromatic system having 6 to 60 carbon atoms. Detailed examples of the C 6 -C 60  aryl group are a phenyl group, a naphthyl group, an anthracenyl group, a phenanthrenyl group, a pyrenyl group, and a chrysenyl group. When the C 6 -C 60  aryl group and the C 6 -C 60  arylene group each include two or more rings, the rings may be fused to each other. 
     A C 2 -C 60  heteroaryl group as used herein refers to a monovalent group having a carbocyclic aromatic system that has at least one hetero atom selected from N, O, P, and S as a ring-forming atom, and 2 to 60 carbon atoms. A C 2 -C 60  heteroarylene group used herein refers to a divalent group having a carbocyclic aromatic system that has at least one hetero atom selected from N, O, P, and S as a ring-forming atom, and 2 to 60 carbon atoms. Detailed example of the C 2 -C 60  heteroaryl group are a pyridinyl group, a pyrimidinyl group, a pyrazinyl group, a pyridazinyl group, a triazinyl group, a quinolinyl group, and an isoquinolinyl group. When the C 2 -C 60  heteroaryl group and the C 2 -C 60  heteroarylene group each include two or more rings, the rings may be fused to each other. 
     The C 6 -C 60  aryloxy group as used herein indicates —OA 102  (wherein A 102  is the C 6 -C 60  aryl group), and the C 6 -C 60  arylthio indicates —SA 103  (wherein A 103  is the C 6 -C 60  aryl group). 
     A monovalent non-aromatic condensed polycyclic group as used herein refers to a monovalent group that has two or more rings condensed to each other, only carbon atoms (for example, the number of carbon atoms may be in a range of 8 to 60) as ring forming atoms, wherein the molecular structure as a whole is non-aromatic. A detailed example of the monovalent non-aromatic condensed polycyclic group is a fluorenyl group. A divalent non-aromatic condensed polycyclic group used herein refers to a divalent group having the same structure as the monovalent non-aromatic condensed polycyclic group. 
     A monovalent non-aromatic condensed heteropolycyclic group used herein refers to a monovalent group that has two or more rings condensed to each other, has a heteroatom selected from N, O P, and S, other than carbon atoms (for example, the number of carbon atoms may be in a range of 2 to 60), as ring forming atoms, wherein the molecular structure as a whole is non-aromatic. A detailed example of the monovalent non-aromatic condensed heteropolycyclic group is a carbazolyl group. A divalent non-aromatic condensed heteropolycyclic group used herein refers to a divalent group having the same structure as the monovalent non-aromatic condensed heteropolycyclic group. 
     At least one substituent of the substituted C 1 -C 60  alkylene group, the substituted C 2 -C 60  alkenylene group, the substituted C 2 -C 60  alkynylene group, the substituted C 3 -C 10  cycloalkylene group, the substituted C 2 -C 10  heterocycloalkylene group, the substituted C 3 -C 10  cycloalkenylene group, the substituted C 2 -C 10  heterocycloalkenylene group, the substituted C 6 -C 60  arylene group, the substituted C 2 -C 60  heteroarylene group, the substituted divalent non-aromatic condensed polycyclic group, the substituted divalent non-aromatic condensed heteropolycyclic group, the substituted C 1 -C 60  alkyl group, the substituted C 2 -C 60  alkenyl group, the substituted C 2 -C 60  alkynyl group, the substituted C 3 -C 10  cycloalkyl group, the substituted C 2 -C 10  heterocycloalkyl group, the substituted C 3 -C 10  cycloalkenyl group, the substituted C 2 -C 10  heterocycloalkenyl group, the substituted C 6 -C 60  aryl group, the substituted C 6 -C 60  aryloxy group, the substituted C 6 -C 60  arythio group, the substituted C 2 -C 60  heteroaryl group, the substituted monovalent non-aromatic condensed polycyclic group, and the substituent monovalent non-aromatic condensed heteropolycyclic group may be selected from 
     a deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, an amino group, an amidino group, a hydrazine group, a hydrazone group, a carboxylic acid group or a salt thereof, a sulfonic acid group or a salt thereof, a phosphoric acid group or a salt thereof, a C 1 -C 60  alkyl group, a C 2 -C 60  alkenyl group, a C 2 -C 60  alkynyl group, and a C 1 -C 60  alkoxy group; 
     a C 1 -C 60  alkyl group, a C 2 -C 60  alkenyl group, a C 2 -C 60  alkynyl group, and a C 1 -C 60  alkoxy group, each substituted with at least one group selected from a deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, an amino group, an amidino group, a hydrazine group, a hydrazone group, a carboxylic acid or a salt thereof, a sulfonic acid group or a salt thereof, a phosphoric acid group or a salt thereof, a C 3 -C 10  cycloalkyl group, a C 2 -C 10  heterocycloalkyl group, a C 3 -C 10  cycloalkenyl group, a C 2 -C 10  heterocycloalkenyl group, a C 6 -C 60  aryl group, a C 6 -C 60  aryloxy group, a C 6 -C 60  arythio group, a C 2 -C 60  heteroaryl group, a monovalent non-aromatic condensed polycyclic group, a monovalent non-aromatic condensed heteropolycyclic group, —N(Q 11 )(Q 12 ), —Si(Q 13 )(Q 14 )(Q 15 ), and —B(Q 16 )(Q 17 ); 
     a C 3 -C 10  cycloalkyl group, a C 2 -C 10  heterocycloalkyl group, a C 3 -C 10  cycloalkenyl group, a C 2 -C 10  heterocycloalkenyl group, a C 6 -C 60  aryl group, a C 6 -C 60  aryloxy group, a C 6 -C 60  arythio group, a C 2 -C 60  heteroaryl group, a monovalent non-aromatic condensed polycyclic group, and a monovalent non-aromatic condensed heteropolycyclic group; 
     a C 3 -C 10  cycloalkyl group, a C 2 -C 10  heterocycloalkyl group, a C 3 -C 10  cycloalkenyl group, a C 2 -C 10  heterocycloalkenyl group, a C 6 -C 60  aryl group, a C 6 -C 60  aryloxy group, a C 6 -C 60  arythio group, a C 2 -C 60  heteroaryl group, a monovalent non-aromatic condensed polycyclic group, a monovalent non-aromatic condensed heteropolycyclic group, each substituted with at least one group selected from a deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, an amino group, an amidino group, a hydrazine group, a hydrazone group, a carboxylic acid or a salt thereof, a sulfonic acid group or a salt thereof, a phosphoric acid group or a salt thereof, a C 1 -C 60  alkyl group, a C 2 -C 60  alkenyl group, a C 2 -C 60  alkynyl group, a C 1 -C 60  alkoxy group, a C 3 -C 10  cycloalkyl group, a C 2 -C 10  heterocycloalkyl group, a C 3 -C 10  cycloalkenyl group, a C 2 -C 10  heterocycloalkenyl group, a C 6 -C 60  aryl group, a C 6 -C 60  aryloxy group, a C 6 -C 60  arythio group, a C 2 -C 60  heteroaryl group, a monovalent non-aromatic condensed polycyclic group, a monovalent non-aromatic condensed heteropolycyclic group, —N(Q 21 )(Q 22 ), —Si(Q 23 )(Q 24 )(Q 25 ), and —B(Q 26 )(Q 27 ); and 
     —N(Q 31 )(Q 32 ), —Si(Q 33 )(Q 34 )(Q 35 ), and —B(Q 36 )(Q 37 ). 
     Also, Q 1  to Q 7 , Q 11  to Q 17 , Q 31  to Q 37 , and Q 31  to Q 37  may be each independently selected from a hydrogen, a C 1 -C 60  alkyl group, a C 2 -C 60  alkenyl group, a C 2 -C 60  alkynyl group, a C 1 -C 60  alkoxy group, a C 3 -C 10  cycloalkyl group, a C 2 -C 10  heterocycloalkyl group, a C 3 -C 10  cycloalkenyl group, a C 2 -C 10  heterocycloalkenyl group, a C 6 -C 60  aryl group, a C 2 -C 60  heteroaryl group, a monovalent non-aromatic condensed polycyclic group, and a monovalent non-aromatic hetero-condensed polycyclic group. 
     For example, at least one substituent of the substituted C 1 -C 60  alkylene group, the substituted C 2 -C 60  alkenylene group, the substituted C 2 -C 60  alkynylene group, the substituted C 3 -C 10  cycloalkylene group, the substituted C 2 -C 10  heterocycloalkylene group, the substituted C 3 -C 10  cycloalkenylene group, the substituted C 2 -C 10  heterocycloalkenylene group, the substituted C 6 -C 60  arylene group, the substituted C 2 -C 60  heteroarylene group, the substituted divalent non-aromatic condensed polycyclic group, the substituted divalent non-aromatic condensed heteropolycyclic group, the substituted C 1 -C 60  alkyl group, the substituted C 2 -C 60  alkenyl group, the substituted C 2 -C 60  alkynyl group, the substituted C 3 -C 10  cycloalkyl group, the substituted C 2 -C 10  heterocycloalkyl group, the substituted C 3 -C 10  cycloalkenyl group, the substituted C 2 -C 10  heterocycloalkenyl group, the substituted C 6 -C 60  aryl group, the substituted C 6 -C 60  aryloxy group, the substituted C 6 -C 60  arythio group, the substituted C 2 -C 60  heteroaryl group, the substituted monovalent non-aromatic condensed polycyclic group, and the substituent monovalent non-aromatic condensed heteropolycyclic group may be selected from 
     a deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, an amino group, an amidino group, a hydrazine group, a hydrazone group, a carboxylic acid group or a salt thereof, a sulfonic acid group or a salt thereof, a phosphoric acid group or a salt thereof, a C 1 -C 60  alkyl group, a C 2 -C 60  alkenyl group, a C 2 -C 60  alkynyl group, and a C 1 -C 60  alkoxy group;
 
a C 1 -C 60  alkyl group, a C 2 -C 60  alkenyl group, a C 2 -C 60  alkynyl group, and a C 1 -C 60  alkoxy group, each substituted with at least one group selected from a deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, an amino group, an amidino group, a hydrazine group, a hydrazone group, a carboxylic acid or a salt thereof, a sulfonic acid group or a salt thereof, a phosphoric acid group or a salt thereof, a C 3 -C 10  cycloalkyl group, a C 2 -C 10  heterocycloalkyl group, a C 3 -C 10  cycloalkenyl group, a C 2 -C 10  heterocycloalkenyl group, a C 6 -C 60  aryl group, a C 6 -C 60  aryloxy group, a C 6 -C 60  arythio group, a C 2 -C 60  heteroaryl group, a monovalent non-aromatic condensed polycyclic group, a monovalent non-aromatic condensed heteropolycyclic group, —N(Q 11 )(Q 12 ), —Si(Q 13 )(Q 14 )(Q 15 ), and —B(Q 16 )(Q 17 );
 
a phenyl group, a pentalenyl group, an indenyl group, a naphthyl group, an azulenyl group, a heptalenyl group, an indacenyl group, an acenaphthyl group, a fluorenyl group, a spiro-fluorenyl group, a phenalenyl group, a phenanthrenyl group, an anthracenyl group, a fluoranthrenyl group, a triphenylenyl group, a pyrenyl group, a chrysenyl group, a naphthacenyl group, a pycenyl group, a perylenyl group, a pentaphenyl group, a hexacenyl group, a pyrrolyl group, an imidazolyl group, a pyrazolyl group, a pyridinyl group, a pyrazinyl group, a pyrimidinyl group, a pyridazinyl group, an isoindolyl group, an indolyl group, an indazolyl group, a purinyl group, a quinolinyl group, an isoquinolinyl group, a benzoquinolinyl group, a phthalazinyl group, a naphthylidinyl group, a quinoxalinyl group, a quinazolinyl group, a cynolinyl group, a carbazolyl group, a phenanthridinyl group, an acridinyl group, a phenanthrolinyl group, a phenazinyl group, a benzooxazolyl group, a benzoimidazolyl group, a furanyl group, a benzofuranyl group, a thiophenyl group, a benzothiophenyl group, a thiazolyl group, an isothiazolyl group, a benzothiazolyl group, an isooxazolyl group, an oxazolyl group, a triazolyl group, a tetrazolyl group, an oxadiazolyl group, a triazinyl group, a dibenzofuranyl group, a dibenzothiophenyl group, a benzocarbazolyl group, a dibenzocarbazolyl group, an imidazopyrimidinyl group, and an imidazopyridinyl group, each substituted with at least one group selected from a cyclopentyl group, a cyclohexyl group, a cycloheptyl group, a cyclooctyl group, a cyclopentenyl group, a cyclohexenyl group, a cycloheptenyl group, a phenyl group, a naphthyl group, an anthracenyl group, a pyrenyl group, a phenanthrenyl group, a fluorenyl group, a carbazolyl group, a benzocarbazolyl group, a dibenzocarbazolyl group, a pyridinyl group, a pyrimidinyl group, a pyrazinyl group, a pyridazinyl group, a triazinyl group, a quinolinyl group, an isoquinolinyl group, a phthalazinyl group, a quinoxalinyl group, a cynolinyl group, and a quinazolinyl group;
 
a phenyl group, a pentalenyl group, an indenyl group, a naphthyl group, an azulenyl group, a heptalenyl group, an indacenyl group, an acenaphthyl group, a fluorenyl group, a spiro-fluorenyl group, a phenalenyl group, a phenanthrenyl group, an anthracenyl group, a fluoranthrenyl group, a triphenylenyl group, a pyrenyl group, a chrysenyl group, a naphthacenyl group, a pycenyl group, a perylenyl group, a pentaphenyl group, a hexacenyl group, a pyrrolyl group, an imidazolyl group, a pyrazolyl group, a pyridinyl group, a pyrazinyl group, a pyrimidinyl group, a pyridazinyl group, an isoindolyl group, an indolyl group, an indazolyl group, a purinyl group, a quinolinyl group, an isoquinolinyl group, a benzoquinolinyl group, a phthalazinyl group, a naphthylidinyl group, a quinoxalinyl group, a quinazolinyl group, a cynolinyl group, a carbazolyl group, a phenanthridinyl group, an acridinyl group, a phenanthrolinyl group, a phenazinyl group, a benzooxazolyl group, a benzoimidazolyl group, a furanyl group, a benzofuranyl group, a thiophenyl group, a benzothiophenyl group, a thiazolyl group, an isothiazolyl group, a benzothiazolyl group, an isooxazolyl group, an oxazolyl group, a triazolyl group, a tetrazolyl group, an oxadiazolyl group, a triazinyl group, a dibenzofuranyl group, a dibenzothiophenyl group, a benzocarbazolyl group, a dibenzocarbazolyl group, an imidazopyrimidinyl group, and an imidazopyridinyl group, each substituted with at least one group selected from a cyclopentyl group, a cyclohexyl group, a cycloheptyl group, a cyclooctyl group, a cyclopentenyl group, a cyclohexenyl group, a cycloheptenyl group, a phenyl group, a naphthyl group, an anthracenyl group, a pyrenyl group, a phenanthrenyl group, a fluorenyl group, a carbazolyl group, a benzocarbazolyl group, a dibenzocarbazolyl group, a pyridinyl group, a pyrimidinyl group, a pyrazinyl group, a pyridazinyl group, a triazinyl group, a quinolinyl group, an isoquinolinyl group, a phthalazinyl group, a quinoxalinyl group, a cynolinyl group, and a quinazolinyl group, each substituted with at least one group selected from a deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, an amino group, an amidino group, a hydrazine group, a hydrazone group, a carboxylic acid or a salt thereof, a sulfonic acid or a salt thereof, a phosphoric acid or a salt thereof, a C 1 -C 60  alkyl group, a C 2 -C 60  alkenyl group, a C 2 -C 60  alkynyl group, a C 1 -C 60  alkoxy group, a C 3 -C 10  cycloalkyl group, a C 2 -C 10  heterocycloalkyl group, a C 3 -C 10  cycloalkenyl group, a C 2 -C 10  heterocycloalkenyl group, a C 6 -C 60  aryl group, a C 6 -C 60  aryloxy group, a C 6 -C 60  arythio group, a C 2 -C 60  heteroaryl group, a monovalent non-aromatic condensed polycyclic group, a monovalent non-aromatic condensed heteropolycyclic group, —N(Q 21 )(Q 22 ), —Si(Q 23 )(Q 24 )(Q 25 ), and —B(Q 26 )(Q 27 ); and
 
—N(Q 31 )(Q 32 ), —Si(Q 33 )(Q 34 )(Q 35 ), and —B(Q 36 )(Q 37 ), wherein
 
Q 1  to Q 7 , Q 11  to Q 17 , and Q 31  to Q 37  may be each independently selected from a phenyl group, a pentalenyl group, an indenyl group, a naphthyl group, an azulenyl group, a heptalenyl group, an indacenyl group, an acenaphthyl group, a fluorenyl group, a spiro-fluorenyl group, a phenalenyl group, a phenanthrenyl group, an anthracenyl group, a fluoranthrenyl group, a triphenylenyl group, a pyrenyl group, a chrysenyl group, a naphthacenyl group, a pycenyl group, a perylenyl group, a pentaphenyl group, a hexacenyl group, a pyrrolyl group, an imidazolyl group, a pyrazolyl group, a pyridinyl group, a pyrazinyl group, a pyrimidinyl group, a pyridazinyl group, an isoindolyl group, an indolyl group, an indazolyl group, a purinyl group, a quinolinyl group, an isoquinolinyl group, a benzoquinolinyl group, a phthalazinyl group, a naphthylidinyl group, a quinoxalinyl group, a quinazolinyl group, a cynolinyl group, a carbazolyl group, a phenanthridinyl group, an acridinyl group, a phenanthrolinyl group, a phenazinyl group, a benzooxazolyl group, a benzoimidazolyl group, a furanyl group, a benzofuranyl group, a thiophenyl group, a benzothiophenyl group, a thiazolyl group, an isothiazolyl group, a benzothiazolyl group, an isooxazolyl group, an oxazolyl group, a triazolyl group, a tetrazolyl group, an oxadiazolyl group, a triazinyl group, a dibenzofuranyl group, a dibenzothiophenyl group, a benzocarbazolyl group, a dibenzocarbazolyl group, an imidazopyrimidinyl group and an imidazopyridinyl group, each substituted with at least one group selected from a hydrogen, a C 1 -C 60  alkyl group, a C 2 -C 60  alkenyl group, a C 2 -C 60  alkynyl group, a C 1 -C 60  alkoxy group, a cyclopentyl group, a cyclohexyl group, a cycloheptyl group, a cyclooctyl group, a cyclopentenyl group, a cyclohexenyl group, a cycloheptenyl group, a phenyl group, a naphthyl group, an anthracenyl group, a pyrenyl group, a phenanthrenyl group, a fluorenyl group, a carbazolyl group, a benzocarbazolyl group, a dibenzocarbazolyl group, a pyridinyl group, a pyrimidinyl group, a pyrazinyl group, a pyridazinyl group, a triazinyl group, a quinolinyl group, an isoquinolinyl group, a phthalazinyl group, a quinoxalinyl group, a cynolinyl group and a quinazolinyl group, but they are not limited thereto.
 
     Hereinafter, a compound and an organic light-emitting device according to embodiments is described in detail with reference to Synthesis Example and Examples. However, the organic light-emitting device is not limited thereto. The wording “B was used instead of A” used in describing Synthesis Examples means that a molar equivalent of A was identical to a molar equivalent of B. 
     EXAMPLE 
     Synthesis Example 1 
     Synthesis of Compound 1 
     Synthesis of Intermediate A 
     
       
         
         
             
             
         
       
     
     In a 1 L round-bottom flask, 50 g (312.09 mmol) of 3,3-dimethyl-1-indanone and 31.46 g (296.48 mmol) of benzaldehyde were suspended in 500 ml of ethanol, and then, 18.73 g (468.13 mmol) of sodium hydroxide was slowly added thereto. After 12 hours of stirring, the reaction solution was concentrated and then, subjected to silicagel column (hexane:methylene chloride=4:1) to obtain 62 g (yield=83%) of Intermediate A as a target compound. 
     Synthesis of Intermediate B 
     
       
         
         
             
             
         
       
     
     In a 1 L round-bottom flask, 62 g (249.68 mmol) of Intermediate A, 58.8 g (249.68 mmol) of 4-bromobenzamidine hydrochloride, and 40.45 g (749.03 mmol) of sodium methoxide were suspended in 500 ml of 2-ethoxyethanol, and then, the resultant mixture was refluxed for 48 hours while stirring. When the reaction stopped, the reaction solution was concentrated, and then, the concentrate was subjected to silicagel column to obtain 40 g (yield=37.4%) of Intermediate B. 
       1 H-NMR (300 MHz, CDCl 3 ) δ 8.50 (d, 2H, J=8.70 Hz), 7.55 (m, 10H), 7.45 (m, 1H), 1.37 (s, 6H). 
     Synthesis of Compound 1 
     
       
         
         
             
             
         
       
     
     In a 500 ml flask, 9.86 g (23.07 mmol) of Intermediate B, 4.24 g (25.38 mmol) of carbazole, 2.11 g (2.31 mmol) of Pd 2 (dba) 3 , 6.65 g (69.22 mmol) of sodium-tert-butoxide, and 0.47 g (2.31 mmol) of tri-tert-butylphosphine (50% in toluene) were suspended in 100 ml of toluene, and then, the resultant mixture was refluxed for 12 hours while stirring. When the reaction stopped, the reaction solution was concentrated and then, the concentrate was subjected to silicagel column to obtain 16 g (yield=50%) of Compound 1. 
       1 H-NMR (300 MHz, CDCl 3 ) δ 8.82 (d, 2H), 8.29 (d, 1H), 8.18 (d, 2H), 7.71 (d, 2H), 7.55 (m, 10H), 7.43 (t, 2H), 7.30 (t, 2H), 1.40 (s, 6H). 
     Synthesis Example 2 
     Synthesis of Compound 2 
     
       
         
         
             
             
         
       
     
     In a 500 L round-bottomed flask, 10 g (23.40 mmol) of Intermediate B, 5.87 g (25.74 mmol) of 4-dibenzothienylboronic acid, 0.81 g (0.70 mmol) of tetrakis(triphenylphosphine)palladium(0), and 6.47 g (46.80 mmol) of potassium carbonate were mixed with 120 ml of toluene and 60 ml of distilled water, and then, the mixture was refluxed for 12 hours while stirring. When the reaction stopped, the reaction solution was cooled to room temperature, and then, extracted and concentrated and then, the result was subjected to silicagel column to obtain 8.69 g (yield=70%) of Compound 2. 
       1 H-NMR (300 MHz, CDCl 3 ) δ 8.11 (d, 2H), 8.01 (d, 1H), 7.73 (d, 2H), 7.62 (d, 2H), 7.53 (m, 11H), 7.31 (t, 2H), 1.45 (s, 6H). 
     Synthesis Example 3 
     Synthesis of Compound 25 
     Synthesis of Intermediate C 
     
       
         
         
             
             
         
       
     
     In a 1 L round-bottom flask, 50 g (201.35 mmol) of Intermediate A, 47.42 g (201.35 mmol) of 3-bromobenzamidine hydrochloride, and 32.62 g (604.06 mmol) of sodium methoxide were suspended in 500 ml of 2-ethoxyethanol, and then, the resultant mixture was refluxed for 48 hours while stirring. When the reaction stopped, the reaction solution was concentrated, and then, the concentrate was subjected to silicagel column to obtain 40 g (yield=46%) of Intermediate C. 
     Synthesis of Compound 25 
     
       
         
         
             
             
         
       
     
     In a 500 ml flask, 10 g (23.40 mmol) of Intermediate C, 4.30 g (25.74 mmol) of carbazole, 2.14 g (2.34 mmol) of Pd 2 (dba) 3 , 6.75 g (70.20 mmol) of sodium-tert-butoxide, and 0.47 g (2.34 mmol) of tri-tert-butylphosphine (50% in toluene) were suspended in 100 ml of toluene, and then, the resultant mixture was refluxed for 12 hours while stirring. When the reaction stopped, the reaction solution was concentrated and then, the concentrate was subjected to silicagel column to obtain 7.12 g (yield=59%) of Compound 25. 
       1 H-NMR (300 MHz, CDCl 3 ) δ 8.60 (d, 2H), 8.13 (d, 1H), 8.05 (d, 2H), 7.71 (d, 2H), 7.51 (m, 12H), 7.43 (t, 2H), 1.42 (s, 6H). 
     Synthesis Example 4 
     Synthesis of Compound 129 
     Synthesis of Intermediate D 
     
       
         
         
             
             
         
       
     
     In a 1 L round-bottom flask, 50 g (312.09 mmol) of 3,3-dimethyl-1-indanone and 54.85 g (296.48 mmol) of 4-bromobenzaldehyde were suspended in 500 ml of ethanol, and then, 18.73 g (468.13 mmol) of sodium hydroxide was slowly added thereto. After 12 hours of stirring, the reaction solution was concentrated and then, subjected to silicagel column (hexane:methylene chloride=4:1) to obtain 70 g (yield=69%) of Intermediate D. 
     Synthesis of Intermediate E 
     
       
         
         
             
             
         
       
     
     In a 1 L round-bottom flask, 70 g (213.92 mmol) of Intermediate D, 33.50 g (213.92 mmol) of benzamidine hydrochloride, and 34.66 g (641.77 mmol) of sodium methoxide were suspended in 100 ml of toluene, and then, the mixture was refluxed for 12 hours while stirring. When the reaction stopped, the reaction solution was concentrated and then, the concentrate was subjected to silicagel column to obtain 42 g (yield=46%) of Intermediate E. 
     Synthesis of Compound 129 
     
       
         
         
             
             
         
       
     
     6.8 g (yield: 57%) of Compound 129 was obtained in the same manner as used to synthesize Compound 1 in Synthesis Example 1, except that 10 g (23.40 mmol) of Intermediate E was used instead of Intermediate B. 
       1 H-NMR (300 MHz, CDCl 3 ) δ 8.52 (d, 2H), 8.29 (d, 1H), 8.00 (m, 4H), 7.55 (m, 12H), 7.30 (t, 2H), 1.38 (s, 6H). 
     Synthesis Example 5 
     Synthesis of Compound 161 
     
       
         
         
             
             
         
       
     
     4.6 g (yield: 37%) of Compound 161 was obtained in the same manner as used to synthesize Compound 2 in Synthesis Example 2, except that 10 g (23.40 mmol) of Intermediate E was used instead of Intermediate B. 
       1 H-NMR (300 MHz, CDCl 3 ) δ 8.09 (d, 2H), 7.90 (d, 1H), 7.61 (d, 2H), 7.47 (d, 2H), 7.53 (m, 11H), 7.31 (t, 2H), 1.41 (s, 6H). 
     Evaluation Example 1 
     HOMO, LUMO, and Triplets (T1) Energy Level Evaluation 
     HOMO, LUMO and T1 energy levels of Compounds 1 and 129 were evaluated according to the method indicated in Table 1, and results thereof are shown in Table 2. 
     
       
         
           
               
               
             
               
                 TABLE 1 
               
               
                   
               
             
            
               
                 HOMO energy 
                 Each compound was diluted in CHCl 3  to a concentration of 1 × 10 −5 M, 
               
               
                 level evaluation 
                 and then, UV absorption spectrum thereof was measured at room 
               
               
                 method 
                 temperature by using Shimadzu UV-350 Spectrometer. A HOMO 
               
               
                   
                 energy level of the compound was calculated by using an optical 
               
               
                   
                 band gap (Eg) measured by the edge of the absorption spectrum. 
               
               
                 LUMO energy 
                 Cyclic voltammetry (CV) (electrolyte: 0.1M Bu 4 NClO 4 /solvent: 
               
               
                 level evaluation 
                 CH 2 Cl 2 /electrode: 3 electrode system (working electrode: GC, 
               
               
                 method 
                 reference electrode: Ag/AgCl, auxiliary electrode: Pt)) were used to 
               
               
                   
                 obtain a potential (V)-current (A) graph of each compound, and then, 
               
               
                   
                 from reduction onset of the graph, the LUMO energy level of each 
               
               
                   
                 compound was calculated. 
               
               
                 T1 energy level 
                 A mixture (each compound was dissolved in an amount of 1 mg in 3 
               
               
                 evaluation method 
                 cc of toluene) of toluene and each compound was loaded into a 
               
               
                   
                 quartz cell, and then, the resultant quartz cell was loaded into liquid 
               
               
                   
                 nitrogen (77K) and a photoluminescence spectrum thereof was 
               
               
                   
                 measured by using a device for measuring photoluminescence, and 
               
               
                   
                 the obtained spectrum was compared with a photoluminescence 
               
               
                   
                 spectrum measured at room temperature, and peaks appearing only 
               
               
                   
                 at low temperature were analyzed to calculate T1 energy levels. 
               
               
                   
               
            
           
         
       
     
     
       
         
           
               
               
               
               
             
               
                 TABLE 2 
               
               
                   
               
               
                 Compound No. 
                 HOMO (eV) 
                 LUMO (eV) 
                 T1 energy level (eV) 
               
               
                   
               
             
            
               
                 Compound 1 
                 5.87 
                 2.42 
                 2.72 
               
               
                 Compound 129 
                 5.90 
                 2.55 
                 2.84 
               
               
                   
               
            
           
         
       
     
     Evaluation Example 2 
     Thermal Characteristics Evaluation 
     Thermal analysis (N 2  atmosphere, a temperature range of room temperature to 800° C. (10° C./min)—TGA, from room temperature to 400° C.—DSC, Pan Type: Pt Pan in disposable Al Pan(TGA), and disposable Al pan(DSC)) was performed on Compounds 1 and 129 by using thermo gravimetric analysis (TGA) and differential scanning calorimetry (DSC), and results thereof are shown in Table 3,  FIG. 2  (TGA data of Compound 1),  FIG. 3  (DSC data of Compound 1),  FIG. 4  (TGA data of Compound 129), and  FIG. 5  (DSC data of Compound 129). According to Table 3 and  FIGS. 1 to 4 , Compounds 1 and 129 have excellent thermal stability. 
     
       
         
           
               
               
               
               
               
             
               
                   
                 TABLE 3 
               
               
                   
                   
               
               
                   
                 Compound No. 
                 Tc (° C.) 
                 Tm (° C.) 
                 Tg (° C.) 
               
               
                   
                   
               
             
            
               
                   
                 Compound 1 
                 — 
                 — 
                 111.40 
               
               
                   
                 Compound 129 
                 — 
                 276.65 
                 112.18 
               
               
                   
                   
               
            
           
         
       
     
     Example 1 
     A glass substrate with a 1,500 Å-thick indium tin oxide (ITO) electrode (first electrode, anode) disposed thereon was washed with distilled water and ultrasonic waves. After the distilled water washing, ultrasonic-waves washing is performed thereon by using a solvent, such as isopropyl alcohol, acetone, or methanol, and then, dried, and then, transferred to a plasma cleaner, and the substrate was cleaned with oxygen plasma for 5 minutes, and then, the substrate was transferred to a vacuum depositor. 
     Compound HT5 was vacuum deposited on the ITO electrode of the glass substrate to form a hole transport layer having a thickness of 1,200 Å, thereby forming a hole transport region. 
     Compound 1 (host) and PhGD (dopant, 7 wt %) were co-deposited on the hole transport region to form an emission layer having a thickness of 300 Å. 
     Balq was vacuum deposited on the emission layer to form a first electron transport layer having a thickness of 50 Å, and Alq 3  was vacuum deposited on the first electron transport layer to form a second electron transport layer having at thickness of 250 Å, and then, LiF was deposited on the second electron transport layer to form an electron injection layer having a thickness of 5 Å, and then, an Al second electrode (cathode) having a thickness of 1,000 Å was formed on the electron injection layer, thereby completing manufacturing an organic light-emitting device. 
     
       
         
         
             
             
         
       
     
     Example 2 
     An organic light-emitting device was manufactured in the same manner as in Example 1, except that as a host, Compound 2 was used instead of Compound 1. 
     Example 3 
     An organic light-emitting device was manufactured in the same manner as in Example 1, except that as a host, Compound 25 was used instead of Compound 1. 
     Example 4 
     An organic light-emitting device was manufactured in the same manner as in Example 1, except that as a host, Compound 129 was used instead of Compound 1. 
     Example 5 
     An organic light-emitting device was manufactured in the same manner as in Example 1, except that as a host, Compound 161 was used instead of Compound 1. 
     Comparative Example 1 
     An organic light-emitting device was manufactured in the same manner as in Example 1, except that as a host, CBP was used instead of Compound 1. 
     
       
         
         
             
             
         
       
     
     Evaluation Example 3 
     Evaluation on Characteristics of an Organic Light-Emitting Device 
     The current density change, brightness change, and emission efficiency of each of the organic light-emitting devices manufactured according to Examples 1 to 5 and Comparative Example 1 were measured. Details of the measurement method are as follows, and results thereof are shown in Table 4: 
     (1) Change in Current Density According to Voltage 
     Regarding the manufactured organic light-emitting devices, while the voltage increased from 0 V to 10 V, the current flowing a unit device was measured by using a current-voltage meter (Keithley 2400), and the current measurement values were divided by an area to evaluate a change in current density according to voltage. 
     (2) Change in Brightness According to Voltage 
     Regarding the manufactured organic light-emitting devices, while the voltage increased from 0 V to 10 V, brightness was measured by using a brightness meter (Minolta Cs-1000A) to evaluate a change in brightness according to voltage. 
     (3) Emission Efficiency Measurement 
     Current efficiency (cd/A) was calculated at the same current density (10 mA/cm 2 ) by using the brightness, the current density, and voltage which were measured in (1) and (2). 
     
       
         
           
               
               
               
               
               
               
             
               
                 TABLE 4 
               
             
            
               
                   
               
               
                   
                   
                   
                 Driving 
                   
                 Color  
               
               
                   
                   
                   
                 Voltage  
                 Efficiency 
                 coordinate 
               
            
           
           
               
               
               
               
               
               
               
            
               
                   
                 Host 
                 Dopant 
                 (V) 
                 (cd/A) 
                 CIE x 
                 CIE y 
               
               
                   
               
            
           
           
               
               
               
               
               
               
               
            
               
                 Example 1 
                 Compound  
                 PhGD 
                 6.8 
                 50.4 
                 0.33 
                 0.62 
               
               
                   
                 1 
                   
                   
                   
                   
                   
               
               
                 Example 2 
                 Compound 
                 PhGD 
                 7.1 
                 54.2 
                 0.34 
                 0.62 
               
               
                   
                 2 
                   
                   
                   
                   
                   
               
               
                 Example 3 
                 Compound  
                 PhGD 
                 6.4 
                 49.2 
                 0.34 
                 0.62 
               
               
                   
                 25 
                   
                   
                   
                   
                   
               
               
                 Example 4 
                 Compound  
                 PhGD 
                 6.5 
                 43.6 
                 0.33 
                 0.62 
               
               
                   
                 129 
                   
                   
                   
                   
                   
               
               
                 Example 5 
                 Compound  
                 PhGD 
                 6.7 
                 47.8 
                 0.33 
                 0.62 
               
               
                   
                 161 
                   
                   
                   
                   
                   
               
               
                 Comparative  
                 CBP 
                 PhGD 
                 8.5 
                 45.4 
                 0.33 
                 0.62 
               
               
                 Example 1 
                   
                   
                   
                   
                   
                   
               
               
                   
               
            
           
         
       
     
     From Table 4, it was confirmed that the organic light-emitting devices of Examples 1 to 5 had a lower driving voltage and a higher efficiency than the organic light-emitting devices of Comparative Example 1. 
     The condensed cyclic compound according to embodiments has excellent electric characteristics and thermal stability. Accordingly, an organic light-emitting device including the condensed cyclic compound may have a low driving voltage, high efficiency, high brightness, and a long lifespan. 
     It should be understood that the exemplary embodiments described therein should be considered in a descriptive sense only and not for purposes of limitation. Descriptions of features or aspects within each embodiment should typically be considered as available for other similar features or aspects in other embodiments. 
     While one or more embodiments have been described with reference to the figures, it will be understood by those of ordinary skill in the art that various changes in form and details may be made therein without departing from the spirit and scope of the present disclosure as defined by the following claims.