Condensed cyclic compound and organic light emitting device comprising same

An organic light-emitting device includes a condensed cyclic compound represented by Formula 1:The condensed cyclic compound has an electron withdrawing group (EWG) substituent and an electron donating group (EDG) substituent at suitable positions, and thus has a low ΔEST and may be used as an effective thermally activated delayed fluorescence (TADF) light-emitting material.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a National Phase Patent Application of International Application Number PCT/KR2019/002818, filed on Mar. 12, 2019, which claims priority to and the benefit of Korean Patent Application Number 10-2018-0114365, filed on Sep. 21, 2018, the entire contents of each of which are incorporated herein by reference.

TECHNICAL FIELD

One or more embodiments of the present disclosure relate to a condensed cyclic compound and an organic light-emitting device including the same.

BACKGROUND ART

Organic light-emitting devices are self-emission devices that, as compared with conventional devices, have wide viewing angles, high contrast ratios, short response times, and/or excellent characteristics in terms of luminance, driving voltage, and/or response speed, and may produce full-color images.

DESCRIPTION OF EMBODIMENTS

Technical Problem

One or more embodiments of the present disclosure are directed toward a condensed cyclic compound and an organic light-emitting device including the same.

Technical Solution to Problem

One or more embodiments of the present disclosure provide a condensed cyclic compound represented by Formula 1:

One or more embodiments of the present disclosure provide an organic light-emitting device including: a first electrode; a second electrode facing the first electrode; an organic layer between the first electrode and the second electrode and including an emission layer; and at least one condensed cyclic compound as described above.

Advantageous Effects of Disclosure

An organic light-emitting device including the aforementioned condensed cyclic compound may have a low driving voltage, a high luminance, a high efficiency, and/or a long lifespan.

MODE OF DISCLOSURE

A condensed cyclic compound is represented by Formula 1:

For example, X1may be selected from N(R12), Si(R12)(R13), B(R12), O, and S, but embodiments of the present disclosure are not limited thereto.

In Formula 1, L1to L2are each independently selected from a substituted or unsubstituted C3-C60carbocyclic group and a substituted or unsubstituted C1-C60heterocyclic group.

In an embodiment, L1to L2may each independently be a group represented by any one of Formulae 3-1 to 3-28:

In Formulae 3-1 to 3-28,Y1is selected from C(Z3)(Z4), N(Z5), Si(Z6)(Z7), O, and S,Z1to Z7may each independently be selected from hydrogen, deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a C1-C20alkyl group, a C1-C20alkoxy group, a cyclopentyl group, a cyclohexyl group, a cycloheptyl group, a cyclopentenyl group, a cyclohexenyl group, a phenyl group, a biphenyl group, a terphenyl group, a naphthyl group, a fluorenyl group, a spiro-bifluorenyl group, a benzofluorenyl group, a dibenzofluorenyl group, a phenanthrenyl group, an anthracenyl group, a fluoranthenyl group, a pyrenyl group, a chrysenyl group, a pyrrolyl group, a thiophenyl group, a furanyl group, a silolyl group, an imidazolyl group, a pyrazolyl group, a thiazolyl group, an isothiazolyl group, an oxazolyl group, an isoxazolyl group, a pyridinyl group, a pyrazinyl group, a pyrimidinyl group, a pyridazinyl group, a benzofuranyl group, a benzothiophenyl group, a benzosilolyl group, a dibenzosilolyl group, and —Si(Q31)(Q32)(Q33),Q31to Q33are each independently selected from a C1-C20alkyl group, a C1-C20alkoxy group, a phenyl group, a biphenyl group, a terphenyl group, a naphthyl group, and a pyridinyl group,d2 is an integer from 0 to 2,d3 is an integer from 0 to 3,d4 is an integer from 0 to 4,d6 is an integer from 0 to 6,d8 is an integer from 0 to 8, and*, *′, and *″ each indicate a binding site to neighboring atom.

For example, L1to L2may each independently be a group represented by any one of Formulae 3-1 to 3-3, 3-11 to 3-16, 3-18, and 3-20 to 3-28.

In Formula 1, a1 to a2 are each independently an integer from 0 to 5.

In an embodiment, a1 may be 0, and a2 may be an integer from 0 to 3.

For example, Ar1to Ar3may each independently be a substituted or unsubstituted C6-C60aryl group, a substituted or unsubstituted C6-C60aryloxy group, a substituted or unsubstituted C6-C60arylthio group, a substituted or unsubstituted C1-C60heteroaryl group, a substituted or unsubstituted monovalent non-aromatic condensed polycyclic group, or a substituted or unsubstituted monovalent non-aromatic condensed heteropolycyclic group, but embodiments of the present disclosure are not limited thereto.

According to an embodiment, Ar1to Ar3may each independently be a group represented by any one selected from Formulae 4-1 to 4-22:

In an embodiment, in Formula 1, at least one of L2(among the number of a2) and Ar3(among the number of b1) may be a π-electron-deficient nitrogen-containing ring.

The π-electron-deficient nitrogen-containing ring may be selected from: a pyridinyl group, a pyrimidinyl group, a triazinyl group, a quinolinyl group, a quinazolinyl group, and a benzoquinazolinyl group; and a pyridinyl group, a pyrimidinyl group, a triazinyl group, a quinolinyl group, a quinazolinyl group, and a benzoquinazolinyl group, each substituted with at least one of deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, an amidino group, a hydrazino group, a hydrazono group, a methyl group, an ethyl group, a propyl group, an isobutyl group, a sec-butyl group, a ter-butyl group, a pentyl group, an isoamyl group, a hexyl group, and a C1-C20alkoxy group.

In an embodiment, in Formula 1, i) X1may be C(R12)(R13), and Ar1and Ar2may each independently be selected from a phenyl group, a ter-butyl group, and a phenyl group substituted with at least one selected from deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, an amidino group, a hydrazino group, a hydrazono group, a methyl group, an ethyl group, a propyl group, an isobutyl group, a sec-butyl group, a ter-butyl group, pentyl group, an isoamyl group, a hexyl group, and a C1-C20alkoxy group,ii) X1may be C(R12)(R13), Ar1may be a dibenzofuranyl group or a dibenzofuranyl group substituted with at least one selected from deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, an amidino group, a hydrazino group, a hydrazono group, a methyl group, an ethyl group, a propyl group, an isobutyl group, a sec-butyl group, a ter-butyl group, a pentyl group, an isoamyl group, a hexyl group, and a C1-C20alkoxy group, and Ar2is a phenyl group or a phenyl group substituted with at least one selected from deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, an amidino group, a hydrazino group, a hydrazono group, a methyl group, an ethyl group, a propyl group, an isobutyl group, a sec-butyl group, a ter-butyl group, a pentyl group, an isoamyl group, a hexyl group, and a C1-C20alkoxy group, oriii) X1may be selected from N(R12), Si(R12)(R13), B(R12), O, and S, and Ar1and Ar2may each independently be a phenyl group substituted with at least one selected from deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, an amidino group, a hydrazino group, a hydrazono group, a methyl group, an ethyl group, a propyl group, an isobutyl group, a sec-butyl group, a ter-butyl group, a pentyl group, an isoamyl group, a hexyl group, and a C1-C20alkoxy group.

In Formula 1, b1 is an integer from 1 to 4.

In an embodiment, R1to R11may each be hydrogen,i) when X1is C(R12)(R13) or Si(R12)(R13), R12and R13may each be a methyl group, andii) when X1is N(R12) or B(R12), R12may be a phenyl group substituted with at least one selected from deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, an amidino group, a hydrazino group, a hydrazono group, a methyl group, an ethyl group, a propyl group, an isobutyl group, a sec-butyl group, a ter-butyl group, a pentyl group, an isoamyl group, a hexyl group, and a C1-C20alkoxy group.

In Formula 1, any two neighboring groups of R1to R13may optionally be linked to each other to form a substituted or unsubstituted C3-C60carbocyclic group or a substituted or unsubstituted C1-C60heterocyclic group.

In an embodiment, the condensed cyclic compound may be any one selected from Compounds 1 to 67, but embodiments of the present disclosure are not limited thereto:

The condensed cyclic compound has a substituent that has properties of an electron withdrawing group (EWG) and a substituent that has properties of an electron donating group (EDG) therein at the same time (simultaneously), and by introducing these substituents at suitable positions (when the EWG and EDG substituents are located at suitable positions), a difference between the energy level of a singlet state and the energy level of a triplet state of the overall compound may be appropriately adjusted. Accordingly, thermally activated delayed fluorescence (TADF) may be exhibited.

The singlet energy level and triplet energy level of the condensed cyclic compound may satisfy the following equation:
ΔEST=S1−T1<0.3 eV.

The condensed cyclic compound includes a structure of Formula 1. For example, when a heteroaryl-based substituent having electron deficiency is included in (bonded to) an acridine moiety of the condensed cyclic compound, the condensed cyclic compound has an acceptor configuration for exhibiting TADF characteristics. The acridine moiety, which is a central skeleton (core), may act as a donor, and the compound may have a structurally twisted configuration due to substitution with the heteroaryl-based substituent, such that ΔESTof the compound is decreased, and thus TADF characteristics may be realized.

Also, the condensed cyclic compound essentially includes a diarylamine substituent on a carbazole moiety, and thus donor characteristics may be further strengthened. The carbon number three position of the carbazole moiety is among the most easily substituted, for example with an additional donor substituent, and corresponds to a para-position of the acridine moiety that is the central skeleton so that it may contribute to strengthening of donor characteristics. In a TADF compound, from a design viewpoint for obtaining a compound having a desired emission wavelength, it is preferable that the arylamine group substituent is introduced to the corresponding location.

Accordingly, an electronic device, for example, an organic light-emitting device, using the condensed cyclic compound represented by Formula 1 may have low driving voltage, high luminance, high efficiency, and/or long lifespan.

Synthesis methods of the condensed cyclic compound represented by Formula 1 may be recognizable by one of ordinary skill in the art by referring to the Examples provided below.

At least one of the condensed cyclic compound represented by Formula 1 may be used between a pair of electrodes in an organic light-emitting device. For example, the condensed cyclic compound may be included in an emission layer. In some embodiments, the condensed cyclic compound represented by Formula 1 may be used as a material for a capping layer located outside a pair of electrodes of an organic light-emitting device.

Accordingly, provided is an organic light-emitting device including a first electrode, a second electrode facing the first electrode, an organic layer between the first electrode and the second electrode and including an emission layer, and at least one condensed cyclic compound represented by Formula 1.

The expression “(an organic layer) includes at least one condensed cyclic compound” used herein may include a case in which “(an organic layer) includes identical condensed cyclic compound” and a case in which “(an organic layer) includes two or more different condensed cyclic compounds.”

For example, the organic layer may include, as the condensed cyclic compound, only Compound 1. In this case, Compound 1 may be included in the emission layer of the organic light-emitting device. In some embodiments, the organic layer may include, as the condensed cyclic compound, Compound 1 and Compound 2. In this case, Compounds 1 and 2 may be included in the same layer (for example, both Compounds 1 and 2 may be included in the emission layer) or in different layers (for example, Compound 1 may be included in the emission layer, and Compound 2 may be included in an electron transport layer).

In an embodiment,the first electrode of the organic light-emitting device may be an anode,the second electrode of the organic light-emitting device may be a cathode,the organic layer may include at least one condensed cyclic compound represented by Formula 1,the organic layer may further include a hole transport region between the first electrode and the emission layer and an electron transport region between the emission layer and the second electrode,the hole transport region may include a hole injection layer, a hole transport layer, an emission auxiliary layer, an electron blocking layer, or any combination thereof, andthe electron transport region may include a hole blocking layer, an electron transport layer, an electron injection layer, or any combination thereof.

In an embodiment, the condensed cyclic compound represented by Formula 1 may be included in the emission layer.

In an embodiment, the condensed cyclic compound included in the emission layer is a delayed fluorescence emitter, andthe emission layer may be to emit delayed fluorescence.

In an embodiment, the emission layer may consist of the condensed cyclic compound, orthe emission layer may further include a host, and an amount of the condensed cyclic compound may be from 0.1 parts by weight to 50 parts by weight based on 100 parts by weight of the emission layer.

For example, the condensed cyclic compound represented by Formula 1 may be a dopant in the emission layer, and the dopant may be a fluorescent dopant.

In an embodiment, the host may include a compound represented by Formula 301:
[Ar301]xb11−[(L301)xb1−R301]xb21.  Formula 301

In Formula 301,Ar301may be a substituted or unsubstituted C5-C60carbocyclic group or a substituted or unsubstituted C1-C60heterocyclic group,xb11 may be 1, 2, or 3,L301may be selected from a substituted or unsubstituted C3-C10cycloalkylene group, a substituted or unsubstituted C1-C10heterocycloalkylene group, a substituted or unsubstituted C3-C10cycloalkenylene group, a substituted or unsubstituted C1-C10heterocycloalkenylene group, a substituted or unsubstituted C6-C60arylene group, a substituted or unsubstituted C1-C60heteroarylene group, a substituted or unsubstituted divalent non-aromatic condensed polycyclic group, and a substituted or unsubstituted divalent non-aromatic condensed heteropolycyclic group,xb1 may be an integer from 0 to 5,R301may be selected from hydrogen, deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, an amidino group, a hydrazino group, a hydrazono group, a substituted or unsubstituted C1-C60alkyl group, a substituted or unsubstituted C2-C60alkenyl group, a substituted or unsubstituted C2-C60alkynyl group, a substituted or unsubstituted C1-C60alkoxy group, a substituted or unsubstituted C3-C10cycloalkyl group, a substituted or unsubstituted C1-C10heterocycloalkyl group, a substituted or unsubstituted C3-C10cycloalkenyl group, a substituted or unsubstituted C1-C10heterocycloalkenyl group, a substituted or unsubstituted C6-C60aryl group, a substituted or unsubstituted C6-C60aryloxy group, a substituted or unsubstituted C6-C60arylthio group, a substituted or unsubstituted C1-C60heteroaryl group, a substituted or unsubstituted monovalent non-aromatic condensed polycyclic group, a substituted or unsubstituted monovalent non-aromatic condensed heteropolycyclic group, —Si(Q301)(Q302)(Q303), —N(Q301)(Q302), —B(Q301)(Q302), —C(═O)(Q301), —S(═O)2(Q301), and —P(═O)(Q301)(Q302), andxb21 may be an integer from 1 to 5,wherein Q301to Q303may each independently be selected from a C1-C10alkyl group, a C1-C10alkoxy group, a phenyl group, a biphenyl group, a terphenyl group, and a naphthyl group.

In an embodiment, the hole transport region may include a p-dopant having a lowest unoccupied molecular orbital (LUMO) energy level of less than −3.5 eV.

According to an embodiment, the electron transport region may include an alkali metal, an alkaline earth metal, a rare earth metal, an alkali metal compound, an alkaline earth-metal compound, a rare earth metal compound, an alkali metal complex, an alkaline earth-metal complex, a rare earth metal complex, or any combination thereof.

The term “organic layer” as used herein may refer to a single layer or all layers between the first electrode and the second electrode of the organic light-emitting device. Materials included in “the organic layer” are not limited to being an organic material.

For example, the organic light-emitting device may have: i) a stacked structure including a first electrode, an organic layer, a second electrode, and a second capping layer, sequentially stacked in this stated order, ii) a stacked structure including a first capping layer, a first electrode, an organic layer, and a second electrode, sequentially stacked in this stated order, or iii) a stacked structure including a first capping layer, a first electrode, an organic layer, a second electrode, and a second capping layer, sequentially stacked in this stated order, and at least one of the first capping layer and the second capping layer may include the condensed cyclic compound.

The term “organic layer” used herein refers to a single layer and/or all layers between the first electrode and the second electrode of the organic light-emitting device. Materials included in “the organic layer” are not limited to being an organic material.

FIG.1is a schematic cross-sectional view of an organic light-emitting device10according to an embodiment. The organic light-emitting device10includes a first electrode110, an organic layer150, and a second electrode190.

Hereinafter, a structure of the organic light-emitting device10according to an embodiment and a method of manufacturing the organic light-emitting device10will be described in connection withFIG.1.

InFIG.1, a substrate may be additionally located under the first electrode110or above the second electrode190. The substrate may be a glass substrate and/or a plastic substrate, each having excellent mechanical strength, thermal stability, transparency, surface smoothness, ease of handling, and/or water resistance.

The first electrode110may be formed by, for example, depositing or sputtering a material for forming the first electrode110on the substrate. When the first electrode110is an anode, the material for forming the first electrode110may be selected from materials with a high work function to facilitate hole injection.

The organic layer150is located on the first electrode110. The organic layer150may include an emission layer.

[Hole Transport Region in Organic Layer150]

The hole transport region may have i) a single-layered structure consisting of a single layer consisting of a single material, ii) a single-layered structure consisting of a single layer consisting of a plurality of different materials, or iii) a multi-layered structure having a plurality of layers consisting of a plurality of different materials.

The hole transport region may include at least one layer selected from a hole injection layer, a hole transport layer, an emission auxiliary layer, and an electron blocking layer.

For example, the hole transport region may have a single-layered structure including a plurality of different materials, or a multi-layered structure having a hole injection layer/hole transport layer structure, a hole injection layer/hole transport layer/emission auxiliary layer structure, a hole injection layer/emission auxiliary layer structure, a hole transport layer/emission auxiliary layer structure, or a hole injection layer/hole transport layer/electron blocking layer structure, wherein the constituting layers of each structure are sequentially stacked on the first electrode110in this stated order, but the structure of the hole transport region is not limited thereto.

In Formulae 201 and 202,L201to L204may each independently be selected from a substituted or unsubstituted C3-C10cycloalkylene group, a substituted or unsubstituted C1-C10heterocycloalkylene group, a substituted or unsubstituted C3-C10cycloalkenylene group, a substituted or unsubstituted C1-C10heterocycloalkenylene group, a substituted or unsubstituted C6-C60arylene group, a substituted or unsubstituted C1-C60heteroarylene group, a substituted or unsubstituted divalent non-aromatic condensed polycyclic group, and a substituted or unsubstituted divalent non-aromatic condensed heteropolycyclic group,L205may be selected from *—O—*′, *—S—*′, *—N(Q201)-*′, a substituted or unsubstituted C1-C20alkylene group, a substituted or unsubstituted C2-C20alkenylene group, a substituted or unsubstituted C3-C10cycloalkylene group, a substituted or unsubstituted C1-C10heterocycloalkylene group, a substituted or unsubstituted C3-C10cycloalkenylene group, a substituted or unsubstituted C1-C10heterocycloalkenylene group, a substituted or unsubstituted C6-C60arylene group, a substituted or unsubstituted C1-C60heteroarylene group, a substituted or unsubstituted divalent non-aromatic condensed polycyclic group, and a substituted or unsubstituted divalent non-aromatic condensed heteropolycyclic group,xa1 to xa4 may each independently be an integer from 0 to 3,xa5 may be an integer from 1 to 10, andR201to R204and Q201may each independently be selected from a substituted or unsubstituted C3-C10cycloalkyl group, a substituted or unsubstituted C1-C10heterocycloalkyl group, a substituted or unsubstituted C3-C10cycloalkenyl group, a substituted or unsubstituted C1-C10heterocycloalkenyl group, a substituted or unsubstituted C6-C60aryl group, a substituted or unsubstituted C6-C60aryloxy group, a substituted or unsubstituted C6-C60arylthio group, a substituted or unsubstituted C1-C60heteroaryl group, a substituted or unsubstituted monovalent non-aromatic condensed polycyclic group, and a substituted or unsubstituted monovalent non-aromatic condensed heteropolycyclic group.

For example, R201and R202in Formula 202 may optionally be linked to each other via a single bond, a dimethyl-methylene group, or a diphenyl-methylene group, and R203and R204may optionally be linked to each other via a single bond, a dimethyl-methylene group, or a diphenyl-methylene group.

In one or more embodiments, xa5 may be 1, 2, 3, or 4.

In one or more embodiments, in Formula 202, i) R201and R202may be linked to each other via a single bond, and/or ii) R203and R204may be linked to each other via a single bond.

In one or more embodiments, the compound represented by Formula 201 may be represented by Formula 201A(1), but embodiments of the present disclosure are not limited thereto:

In one or more embodiments, the compound represented by Formula 201 may be represented by Formula 201A-1, but embodiments of the present disclosure are not limited thereto:

In one or more embodiments, the compound represented by Formula 202 may be represented by Formula 202A:

In one or more embodiments, the compound represented by Formula 202 may be represented by Formula 202A-1:

The hole transport region may include at least one compound selected from compounds HT1 to HT39, but compounds to be included in the hole transport region are not limited thereto:

A thickness of the hole transport region may be about 100 Å to about 10,000 Å, for example, about 100 Å to about 1,000 Å. When the hole transport region includes at least one selected from a hole injection layer and a hole transport layer, the thickness of the hole injection layer may be about 100 Å to about 9,000 Å, for example, about 100 Å to about 1,000 Å, and the thickness of the hole transport layer may be 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 emission auxiliary layer may increase light-emission efficiency of the device by compensating for an optical resonance distance of a wavelength of light emitted by an emission layer, and the electron blocking layer may block or reduce the flow of electrons from an electron transport region. The emission auxiliary layer and the electron blocking layer may include the materials as described above.

The hole transport region may further include, in addition to these materials, a charge-generating material for the improvement of conductive properties. The charge-generating material may be homogeneously or non-homogeneously dispersed in the hole transport region.

The charge-generating material may be, for example, a p-dopant.

In an embodiment, a LUMO energy level of the p-dopant may be −3.5 eV or less.

The p-dopant may include at least one selected from a quinone derivative, a metal oxide, and a cyano group-containing compound, but embodiments of the present disclosure are not limited thereto.

In an embodiment, the p-dopant may include at least one selected from:a quinone derivative, such as tetracyanoquinodimethane (TCNQ) and/or 2,3,5,6-tetrafluoro-7,7,8,8-tetracyanoquinodimethane (F4-TCNQ);a metal oxide, such as tungsten oxide and/or molybdenum oxide;1,4,5,8,9,12-hexaazatriphenylene-hexacarbonitrile (HAT-CN); anda compound represented by Formula 221,but embodiments of the present disclosure are not limited thereto:

When the organic light-emitting device10is a full-color organic light-emitting device, the emission layer may be patterned into a red emission layer, a green emission layer, or a blue emission layer, according to a sub-pixel. In one or more embodiments, the emission layer may have a stacked structure of two or more layers selected from a red emission layer, a green emission layer, and a blue emission layer, in which the two or more layers contact each other or are separated from each other, and are to emit white light. In one or more embodiments, the emission layer may include two or more materials selected from a red light-emitting material, a green light-emitting material, and a blue light-emitting material, in which the two or more materials are mixed with each other in a single layer to emit white light.

The emission layer may include the condensed-cyclic compound represented by Formula 1.

The emission layer may include a host and a dopant. The dopant may include at least one of a phosphorescent dopant and a fluorescent dopant.

An amount of a dopant in the emission layer may be, based on about 100 parts by weight of the host, about 0.01 parts by weight to about 15 parts by weight, but embodiments of the present disclosure are not limited thereto.

The host may include the condensed cyclic compound represented by Formula 1.

The host may further include a compound represented by Formula 301.
[Ar301]xb11−[(L301)xb1−R301]xb21.  Formula 301

In Formula 301,Ar301may be a substituted or unsubstituted C5-C60carbocyclic group or a substituted or unsubstituted C1-C60heterocyclic group,xb11 may be 1, 2, or 3,L301may be selected from a substituted or unsubstituted C3-C10cycloalkylene group, a substituted or unsubstituted C1-C10heterocycloalkylene group, a substituted or unsubstituted C3-C10cycloalkenylene group, a substituted or unsubstituted C1-C10heterocycloalkenylene group, a substituted or unsubstituted C6-C60arylene group, a substituted or unsubstituted C1-C60heteroarylene group, a substituted or unsubstituted divalent non-aromatic condensed polycyclic group, and a substituted or unsubstituted divalent non-aromatic condensed heteropolycyclic group,xb1 may be an integer from 0 to 5,R301may be selected from hydrogen, deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, an amidino group, a hydrazino group, a hydrazono group, a substituted or unsubstituted C1-C60alkyl group, a substituted or unsubstituted C2-C60alkenyl group, a substituted or unsubstituted C2-C60alkynyl group, a substituted or unsubstituted C1-C60alkoxy group, a substituted or unsubstituted C3-C10cycloalkyl group, a substituted or unsubstituted C1-C10heterocycloalkyl group, a substituted or unsubstituted C3-C10cycloalkenyl group, a substituted or unsubstituted C1-C10heterocycloalkenyl group, a substituted or unsubstituted C6-C60aryl group, a substituted or unsubstituted C6-C60aryloxy group, a substituted or unsubstituted C6-C60arylthio group, a substituted or unsubstituted C1-C60heteroaryl group, a substituted or unsubstituted monovalent non-aromatic condensed polycyclic group, a substituted or unsubstituted monovalent non-aromatic condensed heteropolycyclic group, —Si(Q301)(Q302)(Q303), —N(Q301)(Q302), —B(Q301)(Q302), —C(═O)(Q301), —S(═O)2(Q301), and —P(═O)(Q301)(Q302), andxb21 may be an integer from 1 to 5,wherein Q301to Q303may each independently be selected from a C1-C10alkyl group, a C1-C10alkoxy group, a phenyl group, a biphenyl group, a terphenyl group, and a naphthyl group, but embodiments of the present disclosure are not limited thereto.

When xb11 in Formula 301 is two or more, two or more Ar301(s) may be linked via a single bond.

In one or more embodiments, the compound represented by Formula 301 may be represented by Formula 301-1 or Formula 301-2:

In an embodiment, the host may include an alkaline earth metal complex. For example, the host may be selected from a Be complex (for example, Compound H55) and an Mg complex. In some embodiments, the host may be a Zn complex.

[Phosphorescent Dopant Included in Emission Layer in Organic Layer150]

In Formulae 401 and 402,M may be selected from iridium (Ir), platinum (Pt), palladium (Pd), osmium (Os), titanium (Ti), zirconium (Zr), hafnium (Hf), europium (Eu), a terbium (Tb), rhodium (Rh), and thulium (Tm),L401may be a ligand represented by Formula 402, and xc1 may be 1, 2, or 3, wherein when xc1 is two or more, two or more L401(s) may be identical to or different from each other,L402may be an organic ligand, and xc2 may be an integer from 0 to 4, wherein when xc2 is two or more, two or more L402(s) may be identical to or different from each other,X401to X404may each independently be nitrogen or carbon,X401and X403may each independently be linked via a single bond or a double bond, and X402and X404may be linked via a single bond or a double bond,A401and A402may each independently be a C5-C60carbocyclic group or a C1-C60heterocyclic group,X405may be a single bond, *—O—*′, *—S—*′, *—C(═O)—*′, *—N(Q411)-*′, *—C(Q411)(Q412)-*′, *—C(Q411)═C(Q412)-*′, *—C(Q411)=*′, or *═C═*′, wherein Q411and Q412may each independently be hydrogen, deuterium, a C1-C20alkyl group, a C1-C20alkoxy group, a phenyl group, a biphenyl group, a terphenyl group, or a naphthyl group,X406may be a single bond, O, or S,R401and R402may each independently be selected from hydrogen, deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, an amidino group, a hydrazino group, a hydrazono group, a substituted or unsubstituted C1-C20alkyl group, a substituted or unsubstituted C1-C20alkoxy group, a substituted or unsubstituted C3-C10cycloalkyl group, a substituted or unsubstituted C1-C10heterocycloalkyl group, a substituted or unsubstituted C3-C10cycloalkenyl group, a substituted or unsubstituted C1-C10heterocycloalkenyl group, a substituted or unsubstituted C6-C60aryl group, a substituted or unsubstituted C6-C60aryloxy group, a substituted or unsubstituted C6-C60arylthio group, a substituted or unsubstituted C1-C60heteroaryl group, a substituted or unsubstituted monovalent non-aromatic condensed polycyclic group, and a substituted or unsubstituted monovalent non-aromatic condensed heteropolycyclic group, —Si(Q401)(Q402)(Q403), —N(Q401)(Q402), —B(Q401)(Q402), —C(═O)(Q401), —S(═O)2(Q401), and —P(═O)(Q401)(Q402), and Q401to Q403may each independently be selected from a C1-C10alkyl group, a C1-C10alkoxy group, a C6-C20aryl group, and a C1-C20heteroaryl group,xc11 and xc12 may each independently be an integer from 0 to 10, and* and *′ in Formula 402 each indicate a binding site to M in Formula 401.

In one or more embodiments, in Formula 402, i) X401may be nitrogen, and X402may be carbon, or ii) both X401and X402may be nitrogen.

In one or more embodiments, when xc1 in Formula 401 is two or more, two A401(s) in two or more L401(s) may optionally be linked to each other via X407(which is a linking group), two A402(s) may optionally be linked to each other via X408(which is a linking group, see Compounds PD1 to PD4 and PD7). X407and X408may each independently be a single bond, *—S—*′, *—C(═O)—*′, *—N(Q413)-*′, *—C(Q413)(Q414)-*′, or *—C(Q413)═C(Q414)-*′ (wherein Q413and Q414may each independently be hydrogen, deuterium, a C1-C20alkyl group, a C1-C20alkoxy group, a phenyl group, a biphenyl group, a terphenyl group, or a naphthyl group), but embodiments of the present disclosure are not limited thereto.L402in Formula 401 may be a monovalent, divalent, or trivalent organic ligand. For example, L402may be selected from halogen, diketone (for example, acetylacetonate), carboxylic acid (for example, picolinate), —C(═O), isonitrile, —CN, and a phosphorus-containing material (for example, phosphine or phosphite), but embodiments of the present disclosure are not limited thereto.

In one or more embodiments, the phosphorescent dopant may be selected from, for example, Compounds PD1 to PD25, but embodiments of the present disclosure are not limited thereto:

The fluorescent dopant may include the condensed cyclic compound represented by Formula 1.

The fluorescent dopant may include an arylamine compound or a styrylamine compound.

The fluorescent dopant may include a compound represented by Formula 501:

In Formula 501,Ar501may be a substituted or unsubstituted C5-C60carbocyclic group or a substituted or unsubstituted C1-C60heterocyclic group,L501to L503may each independently be selected from a substituted or unsubstituted C3-C10cycloalkylene group, a substituted or unsubstituted C1-C10heterocycloalkylene group, a substituted or unsubstituted C3-C10cycloalkenylene group, a substituted or unsubstituted C1-C10heterocycloalkenylene group, a substituted or unsubstituted C6-C60arylene group, a substituted or unsubstituted C1-C60heteroarylene group, a substituted or unsubstituted divalent non-aromatic condensed polycyclic group, and a substituted or unsubstituted divalent non-aromatic condensed heteropolycyclic group,xd1 to xd3 may each independently be an integer from 0 to 3,R501and R502may each independently be selected from a substituted or unsubstituted C3-C10cycloalkyl group, a substituted or unsubstituted C1-C10heterocycloalkyl group, a substituted or unsubstituted C3-C10cycloalkenyl group, a substituted or unsubstituted C1-C10heterocycloalkenyl group, a substituted or unsubstituted C6-C60aryl group, a substituted or unsubstituted C6-C60aryloxy group, a substituted or unsubstituted C6-C60arylthio group, a substituted or unsubstituted C1-C60heteroaryl group, a substituted or unsubstituted monovalent non-aromatic condensed polycyclic group, and a substituted or unsubstituted monovalent non-aromatic condensed heteropolycyclic group, andxd4 may be an integer from 1 to 6.

In one or more embodiments, xd4 in Formula 501 may be 2, but embodiments of the present disclosure are not limited thereto.

In an embodiment, the fluorescent dopant may be selected from Compounds FD1 to FD22:

In one or more embodiments, the fluorescent dopant may be selected from the following compounds, but embodiments of the present disclosure are not limited thereto.

[Electron Transport Region in Organic Layer150]

The electron transport region may have i) a single-layered structure consisting of a single layer consisting of a single material, ii) a single-layered structure consisting of a single layer consisting of a plurality of different materials, or iii) a multi-layered structure having a plurality of layers consisting of a plurality of different materials.

The electron transport region may include at least one selected from a buffer layer, a hole blocking layer, an electron control layer, an electron transport layer, and an electron injection layer, but embodiments of the present disclosure are not limited thereto.

For example, the electron transport region may have an electron transport layer/electron injection layer structure, a hole blocking layer/electron transport layer/electron injection layer structure, an electron control layer/electron transport layer/electron injection layer structure, or a buffer layer/electron transport layer/electron injection layer structure, wherein the constituting layers of each structure, are sequentially stacked from an emission layer. However, embodiments of the structure of the electron transport region are not limited thereto.

The electron transport region (for example, a buffer layer, a hole blocking layer, an electron control layer, or an electron transport layer in the electron transport region) may include a metal-free compound containing at least one π-electron-deficient nitrogen-containing ring.

The term “π-electron-deficient nitrogen-containing ring” refers to a C1-C60heterocyclic group having at least one *—N═*′ moiety as a ring-forming moiety.

For example, the electron transport region may include a compound represented by Formula 601:
[Ar601]xe11−[(L601)xe1−R601]xe21.  Formula 601

In Formula 601,Ar601may be a substituted or unsubstituted C5-C60carbocyclic group or a substituted or unsubstituted C1-C60heterocyclic group,xe11 may be 1, 2, or 3,L601may be selected from a substituted or unsubstituted C3-C10cycloalkylene group, a substituted or unsubstituted C1-C10heterocycloalkylene group, a substituted or unsubstituted C3-C10cycloalkenylene group, a substituted or unsubstituted C1-C10heterocycloalkenylene group, a substituted or unsubstituted C6-C60arylene group, a substituted or unsubstituted C1-C60heteroarylene group, a substituted or unsubstituted divalent non-aromatic condensed polycyclic group, and a substituted or unsubstituted divalent non-aromatic condensed heteropolycyclic group,xe1 may be an integer from 0 to 5,R601may be selected from a substituted or unsubstituted C3-C10cycloalkyl group, a substituted or unsubstituted C1-C10heterocycloalkyl group, a substituted or unsubstituted C3-C10cycloalkenyl group, a substituted or unsubstituted C1-C10heterocycloalkenyl group, a substituted or unsubstituted C6-C60aryl group, a substituted or unsubstituted C6-C60aryloxy group, a substituted or unsubstituted C6-C60arylthio group, a substituted or unsubstituted C1-C60heteroaryl group, a substituted or unsubstituted monovalent non-aromatic condensed polycyclic group, a substituted or unsubstituted monovalent non-aromatic condensed heteropolycyclic group, —Si(Q601)(Q602)(Q603), —C(═O)(Q601), —S(═O)2(Q601), and —P(═O)(Q601)(Q602),Q601to Q603may each independently be a C1-C10alkyl group, a C1-C10alkoxy group, a phenyl group, a biphenyl group, a terphenyl group, or a naphthyl group, andxe21 may be an integer from 1 to 5.

In an embodiment, at least one of Ar601(s) in the number of xe11 and R601(s) in the number of xe21 may include the π-electron-deficient nitrogen-containing ring.

When xe11 in Formula 601 is 2 or more, two or more Ar601(s) may be linked to each other via a single bond.

In one or more embodiments, Ar601in Formula 601 may be an anthracene group.

In one or more embodiments, the compound represented by Formula 601 may be represented by Formula 601-1:

In Formula 601-1,X614may be N or C(R614), X615may be N or C(R615), X616may be N or C(R616), and at least one of X614to X616may be N,L611to L613may each independently be the same as described in connection with L601,xe611 to xe613 may each independently be the same as described in connection with xe1,R611to R613may each independently be the same as described in connection with R601, andR614to R616may each independently be selected from hydrogen, deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, an amidino group, a hydrazino group, a hydrazono group, a C1-C20alkyl group, a C1-C20alkoxy group, a phenyl group, a biphenyl group, a terphenyl group, and a naphthyl group.

The electron transport region may include at least one compound selected from Compounds ET1 to ET36, but embodiments of the present disclosure are not limited thereto:

The thicknesses of the buffer layer, the hole blocking layer, and the electron control layer may each independently be about 20 Å to about 1,000 Å, for example, about 30 Å to about 300 Å. When the thicknesses of the buffer layer, the hole blocking layer, and the electron control layer are within these ranges, excellent hole blocking characteristics or excellent electron control characteristics may be obtained without a substantial increase in driving voltage.

The metal-containing material may include at least one selected from an alkali metal complex and an alkaline earth-metal complex. A metal ion of the alkali metal complex may be selected from a lithium (Li) ion, a sodium (Na) ion, a potassium (K) ion, a rubidium (Rb) ion, and a cesium (Cs) ion, and a metal ion of the alkaline earth-metal complex may be selected from a beryllium (Be) ion, a magnesium (Mg) ion, a calcium (Ca) ion, a strontium (Sr) ion, and a barium (Ba) ion. A ligand coordinated with the metal ion of the alkali metal complex or the alkaline earth-metal complex may be selected from a hydroxy quinoline, a hydroxy isoquinoline, a hydroxy benzoquinoline, a hydroxy acridine, a hydroxy phenanthridine, a hydroxy phenyloxazole, a hydroxy phenylthiazole, a hydroxy diphenyloxadiazole, a hydroxy diphenylthiadiazole, a hydroxy phenylpyridine, a hydroxy phenylbenzimidazole, a hydroxy phenylbenzothiazole, a bipyridine, a phenanthroline, and a cyclopentadiene, but embodiments of the present disclosure are not limited thereto.

The electron transport region may include an electron injection layer to facilitate the injection of electrons from the second electrode190. The electron injection layer may directly contact the second electrode190.

The electron injection layer may have i) a single-layered structure consisting of a single layer consisting of a single material, ii) a single-layered structure consisting of a single layer consisting of a plurality of different materials, or iii) a multi-layered structure having a plurality of layers consisting of a plurality of different materials.

The electron injection layer may include an alkali metal, an alkaline earth metal, a rare earth metal, an alkali metal compound, an alkaline earth-metal compound, a rare earth metal compound, an alkali metal complex, an alkaline earth-metal complex, a rare earth metal complex, or any combination thereof.

The alkali metal may be selected from Li, Na, K, Rb, and Cs. In an embodiment, the alkali metal may be Li, Na, or Cs. In one or more embodiments, the alkali metal may be Li or Cs, but embodiments of the present disclosure are not limited thereto.

The rare earth metal may be selected from scandium (Sc), yttrium (Y), cerium (Ce), terbium (Tb), ytterbium (Yb), and gadolinium (Gd).

The alkali metal compound, the alkaline earth-metal compound, and the rare earth metal compound may be selected from oxides and halides (for example, fluorides, chlorides, bromides, or iodides) of the alkali metal, the alkaline earth metal, and the rare earth metal.

The alkali metal compound may be selected from alkali metal oxides (such as Li2O, Cs2O, and/or K2O), and alkali metal halides (such as LiF, NaF, CsF, KF, LiI, NaI, CsI, and/or KI). In an embodiment, the alkali metal compound may be selected from LiF, Li2O, NaF, LiI, NaI, CsI, and KI, but embodiments of the present disclosure are not limited thereto.

In an embodiment, the alkaline earth-metal compound may be selected from BaO, SrO, and CaO, but embodiments of the present disclosure are not limited thereto.

The rare earth metal compound may be selected from YbF3, ScF3, ScO3, Y2O3, Ce2O3, GdF3, and TbF3. In an embodiment, the rare earth metal compound may be selected from YbF3, ScF3, TbF3, YbI3, ScI3, and TbI3, but embodiments of the present disclosure are not limited thereto.

The alkali metal complex, the alkaline earth-metal complex, and the rare earth metal complex may include an ion of alkali metal, alkaline earth-metal, and rare earth metal as described above, and a ligand coordinated with a metal ion of the alkali metal complex, the alkaline earth-metal complex, or the rare earth metal complex may be selected from hydroxy quinoline, hydroxy isoquinoline, hydroxy benzoquinoline, hydroxy acridine, hydroxy phenanthridine, hydroxy phenyloxazole, hydroxy phenylthiazole, hydroxy diphenyloxadiazole, hydroxy diphenylthiadiazole, hydroxy phenylpyridine, hydroxy phenylbenzimidazole, hydroxy phenylbenzothiazole, bipyridine, phenanthroline, and cyclopentadiene, but embodiments of the present disclosure are not limited thereto.

The electron injection layer may consist of an alkali metal, an alkaline earth metal, a rare earth metal, an alkali metal compound, an alkaline earth-metal compound, a rare earth metal compound, an alkali metal complex, an alkaline earth-metal complex, a rare earth metal complex, or any combination thereof, as described above. In one or more embodiments, the electron injection layer may further include an organic material. When the electron injection layer further includes the organic material, an alkali metal, an alkaline earth metal, a rare earth metal, an alkali metal compound, an alkaline earth-metal compound, a rare earth metal compound, an alkali metal complex, an alkaline earth-metal complex, a rare earth metal complex, or any combination thereof may be homogeneously or non-homogeneously dispersed in a matrix including the organic material.

The second electrode190is located on the organic layer150having such a structure. The second electrode190may be a cathode, which is an electron injection electrode, and in this regard, a material for forming the second electrode190may be selected from a metal, an alloy, an electrically conductive compound, and a combination thereof, each having a relatively low work function.

The second electrode190may include at least one selected from lithium (Li), silver (Ag), magnesium (Mg), aluminum (Al), aluminum-lithium (Al—Li), calcium (Ca), magnesium-indium (Mg—In), magnesium-silver (Mg—Ag), ITO, and IZO, but embodiments of the present disclosure are not limited thereto. The second electrode190may be a transmissive electrode, a semi-transmissive electrode, or a reflective electrode.

An organic light-emitting device20ofFIG.2includes a first capping layer210, a first electrode110, an organic layer150, and a second electrode190, sequentially stacked in this stated order. An organic light-emitting device30ofFIG.3includes a first electrode110, an organic layer150, a second electrode190, and a second capping layer220, sequentially stacked in this stated order. An organic light-emitting device40ofFIG.4includes a first capping layer210, a first electrode110, an organic layer150, a second electrode190, and a second capping layer220.

RegardingFIGS.2to4, the first electrode110, the organic layer150, and the second electrode190may be understood by referring to the description presented in connection withFIG.1.

In the organic layer150of each of the organic light-emitting devices20and40, light generated in an emission layer may pass through the first electrode110(which is a semi-transmissive electrode or a transmissive electrode) and the first capping layer210toward the outside, and in the organic layer150of each of the organic light-emitting devices30and40, light generated in an emission layer may pass through the second electrode190(which is a semi-transmissive electrode or a transmissive electrode) and the second capping layer220toward the outside.

The first capping layer210and the second capping layer220may increase the external luminescence efficiency of the device according to the principle of constructive interference.

The first capping layer210and the second capping layer220may each independently be an organic capping layer consisting of an organic material, an inorganic capping layer consisting of an inorganic material, or a composite capping layer including an organic material and an inorganic material.

At least one of the first capping layer210and the second capping layer220may each independently include at least one material selected from carbocyclic compounds, heterocyclic compounds, amine-based compounds, porphyrin derivatives, phthalocyanine derivatives, naphthalocyanine derivatives, alkali metal complexes, and alkaline earth-metal complexes. The carbocyclic compound, the heterocyclic compound, and the amine-based compound may be optionally substituted with a substituent containing at least one element selected from O, N, S, Se, Si, F, Cl, Br, and I.

In an embodiment, at least one of the first capping layer210and the second capping layer220may each independently include an amine-based compound.

In an embodiment, at least one of the first capping layer210and the second capping layer220may each independently include the compound represented by Formula 201 or the compound represented by Formula 202.

In one or more embodiments, at least one of the first capping layer210and the second capping layer220may each independently include a compound selected from Compounds HT28 to HT33 and Compounds CP1 to CP5, but embodiments of the present disclosure are not limited thereto.

Hereinbefore, the organic light-emitting device has been described in connection withFIGS.1to4. However, embodiments of the present disclosure are not limited thereto.

The layers constituting the hole transport region, the emission layer, and the layers constituting the electron transport region may each be formed in a certain region using one or more suitable methods selected from vacuum deposition, spin coating, casting, Langmuir-Blodgett (LB) deposition, ink-jet printing, laser-printing, and laser-induced thermal imaging (LITI).

General Definition of Substituents

The term “monovalent non-aromatic condensed heteropolycyclic group” as used herein refers to a monovalent group (for example, having 1 to 60 carbon atoms) having two or more rings condensed to each other, at least one heteroatom selected from nitrogen (N), oxygen (O), silicon (Si), phosphorus (P), and sulfur (S) as a ring-forming atom other than the carbon atoms, and non-aromaticity in its entire molecular structure (when considered in its entirety it is not aromatic). Examples of the monovalent non-aromatic condensed heteropolycyclic group include a carbazolyl group. The term “divalent non-aromatic condensed heteropolycyclic group” as used herein refers to a divalent group having substantially the same structure as the monovalent non-aromatic condensed heteropolycyclic group.

The term “C5-C60carbocyclic group” as used herein refers to a monocyclic or polycyclic group that includes only carbon as a ring-forming atom and consists of 5 to 60 carbon atoms. The C5-C60carbocyclic group may be an aromatic carbocyclic group or a non-aromatic carbocyclic group. The C5-C60carbocyclic group may be a ring (such as benzene), a monovalent group (such as a phenyl group), or a divalent group (such as a phenylene group). In one or more embodiments, depending on the number of substituents connected to the C5-C60carbocyclic group, the C5-C60carbocyclic group may be a trivalent group or a quadrivalent group.

The term “C1-C60heterocyclic group” as used herein refers to a group having substantially the same structure as the C5-C60carbocyclic group, except that as a ring-forming atom, at least one heteroatom selected from N, O, Si, P, and S is used in addition to carbon (the number of carbon atoms may be in the range of 1 to 60).

The term “terphenyl group” as used herein refers to “a phenyl group substituted with a biphenyl group.” The “terphenyl group” is “a substituted phenyl group” having, as a substituent, “a C6-C60aryl group substituted with a C6-C60aryl group”.* and *′ as used herein, unless defined otherwise, each refer to a binding site to a neighboring atom in a corresponding formula.

Hereinafter, a compound according to embodiments and an organic light-emitting device according to embodiments will be described in more detail with reference to Synthesis Examples and Examples. The wording “B was used instead of A” used in describing Synthesis Examples indicates that an identical molar equivalent of B was used in place of A.

EXAMPLES

Synthesis Example 1: Synthesis of Compound 5

1) Synthesis of Intermediate 5-2

5 g (12 mmol) of Intermediate 5-1, 3.7 g (15 mmol) of bispinacolatodiboron, 0.5 g (0.35 mmol) of palladium (II) chloride-1,1′-bis(diphenylphosphino)ferrocene, and 2.4 g (24 mmol) of potassium acetate, and 50 mL of toluene were added to a reactor and stirred while refluxing for 10 hours. After completion of the reaction, a solid was filtered, and a filtrate was concentrated under reduced pressure. A separation process was performed thereon by using column chromatography to thereby obtain 3.2 g of Intermediate 5-2 (yield of 58%).

2) Synthesis of Intermediate 5-3

3 g (6.5 mmol) of Intermediate 5-2, 2.4 g (7.7 mmol) of 2-bromo-4,6-diphenyl-1,3,5-triazine, 1.8 g (13 mmol) of potassium carbonate, 1.2 g (0.1 mmol) of tetrakistriphenylphosphine palladium, 30 mL of distilled water, 50 mL of toluene, and 50 mL of 1,4-dioxane were added to a reactor and stirred while refluxing for 24 hours. After completion of the reaction, the mixture was concentrated under reduced pressure, and a separation process was performed thereon using column chromatography to thereby obtain 2.7 g of Intermediate 5-3 (yield of 73%).

3) Synthesis of Intermediate 5-4

After a reactor was filled with nitrogen, 2.5 g (4.4 mmol) of Intermediate 5-3 and 20 mL of dimethylformamide were added thereto and stirred. Afterward, 0.78 g (4.4 mmol) of N-bromosuccinimide was slowly added thereto and stirred at room temperature for 5 hours. When the reaction is completed, distilled water was added dropwise thereto at room temperature, and when a solid was formed, the solid was filtered and separated by column chromatography, to thereby obtain 2.5 g of Intermediate 5-4 (yield of 87%).

4) Synthesis of Compound 5

2.5 g (3.8 mmol) of Intermediate 5-4, 0.84 g (5.0 mmol) of diphenylamine, 0.18 g (0.15 mmol) of tetrakis(triphenylphosphine)palladium, 1.5 g (11 mmol) of potassium carbonate, 10 mL of 1,4-dioxane, 20 mL of toluene, and 10 mL of distilled water were added to a reactor under nitrogen atmosphere and stirred at 120° C. for 12 hours. When the reaction is completed, an extraction process was performed thereon using ethyl acetate and distilled water. An organic layer was concentrated under reduced pressure and was separated by column chromatography to thereby obtain 1.6 g of Compound 5 (MS 731.3, yield of 57%).

Synthesis Example 2: Synthesis of Compound 7

1) Synthesis of Intermediate 7-1

2.3 g of Intermediate 7-1 (yield of 51%) was obtained in substantially the same manner and route as in the Synthesis of Intermediate 5-3, except that 4′-bromo-2,2′:6′,2″-terpyridine was used instead of 2-bromo-4,6-diphenyl-1,3,5-triazine.

2) Synthesis of Intermediate 7-2

2.5 g of Intermediate 7-2 (yield of 92%) was obtained in substantially the same manner and route as in the Synthesis of Intermediate 5-4, except that Intermediate 7-1 was used instead of Intermediate 5-3.

3) Synthesis of Compound 7

1.1 g of Compound 7 (MS 731.3, yield of 42%) was obtained in substantially the same manner and route as in the Synthesis of Compound 5, except that Intermediate 7-2 was used instead of Intermediate 5-4.

Synthesis Example 3: Synthesis of Compound 25

1.7 g of Compound 25 (MS 843.4, yield of 54%) was obtained in substantially the same manner and route as in synthesis of Compound 5, except that bis(4-(tert-butyl)phenyl)amine was used instead of diphenylamine.

Compounds other than the compounds shown in Synthesis Examples 1 to 3 may be easily recognized by those skilled in the art by referring to the above synthesis routes and source materials.

As an anode, a glass substrate with 15 Ω/cm2(1,200 Å) ITO thereon, manufactured by Corning Inc., was cut to a size of 50 mm×50 mm×0.5 mm, sonicated using isopropyl alcohol and pure water for 15 minutes each, and then cleaned by irradiation of ultraviolet rays and ozone exposure for 30 minutes. Then, the resultant glass substrate was loaded onto a vacuum deposition apparatus.

m-MTDATA was vacuum-deposited on the substrate to form a hole injection layer having a thickness of 70 nm, and as a hole transport compound, 4,4′,4″-tris(N-carbazolyl)triphenylamine (TCTA) was vacuum-deposited thereon to form a hole transport layer having a thickness of 10 nm.

CBP as a known host and Compound 5 as a fluorescent dopant were co-deposited on the hole transport layer at a weight ratio of 80:20 to form an emission layer having a thickness of 30 nm.

Subsequently, ET1 was deposited on the emission layer to form an electron transport layer having a thickness of 30 nm, LiF was deposited on the electron transport layer to form an electron injection layer having a thickness of 1 nm, and Al was vacuum-deposited thereon to form an LiF/Al electrode having a thickness of 200 nm, thereby completing manufacture of an organic light-emitting device.

Examples 2 and 3

Additional organic light-emitting devices were manufactured in substantially the same manner as in Example 1, except that the compounds described in Table 1 were respectively used instead of Compound 5 in forming an emission layer.

Comparative Examples 1 to 3

Organic light-emitting devices were manufactured in substantially the same manner as in Example 1, except that Compounds A to C were respectively used instead of Compound 5 in forming an emission layer.

Comparative Example 4

An organic light-emitting device was manufactured in substantially the same manner as in Example 1, except that C545T was used instead of Compound 5 in forming an emission layer.

Evaluation Example 1

With respect to each of the organic light-emitting devices manufactured in Examples 1 to 3 and Comparative Examples 1 to 3, the luminescence efficiency and lifespan were measured at 5,000 nit using a Keithley SMU 236 and a luminance meter PR650, and results thereof are shown in Table 1. The efficiency and lifespan were expressed by converting the values to percentages (%) compared to the efficiency and lifespan of Comparative Example 4 (taken as 100%.)

From Table 1, when a compound of the present disclosure was used as a dopant material of an emission layer, green emission color was exhibited, and excellent luminescence efficiency and maximum quantum efficiency were exhibited, as compared to a case in which Comparative Compound was used as a dopant. Accordingly, the compound of the present disclosure has a low ΔESTand may be used as an effective delayed fluorescent light-emitting material.

Although the present disclosure has been described with reference to the Synthesis Examples and Examples, these examples are provided for illustrative purpose only, and one of ordinary skill in the art may understand that these examples may have various modifications and other examples equivalent thereto. Accordingly, the scope of the present disclosure should be determined by the technical concept of the claims.