ORGANOMETALLIC COMPOUND AND ORGANIC LIGHT-EMITTING DEVICE INCLUDING THE SAME

An organometallic compound represented by Formula 1 or 2 and an organic light-emitting device including the same.

CROSS-REFERENCE TO RELATED APPLICATION

This application claims priority to and the benefit of Korean Patent Application No. 10-2018-0028303, filed on Mar. 9, 2018, in the Korean Intellectual Property Office, the disclosure of which is incorporated herein in its entirety by reference.

BACKGROUND

One or more embodiments relate to an organometallic compound and an organic light-emitting device including the same.

2. Description of the Related Art

Organic light-emitting devices are self-emission devices that produce full-color images, and also have wide viewing angles, high contrast ratios, short response times, and excellent characteristics in terms of brightness, driving voltage, and response speed, compared to devices in the art.

SUMMARY

Aspects of the present disclosure are directed toward a novel organometallic compound and an organic light-emitting device including the same.

According to an embodiment, an organometallic compound is represented by Formula 1 or 2:

In Formulae 1 and 2,

A11to A13may each independently be selected from a C5-C60carbocyclic group and a C1-C60heterocyclic group, wherein A11in Formula 1 is not represented by a

Y11to Y13may each independently be selected from a carbon atom (C) and a nitrogen atom (N),

B11to B14may each independently be selected from a single bond, O, and S,

a11, a12, and a14 may each independently be an integer from 0 to 3, and a13 may be an integer from 1 to 3, wherein at least two of a11, a12, and a14 may each independently be an integer from 1 to 3,

when a11 is 0, A11and A12may not be linked to each other, when a12 is 0, A12and A13may not be linked to each other, when a13 is 0, A13and a nitrogen atom (N) may not be linked to each other, and when a14 is 0, A11and X15in Formula 1 and A11and X19in Formula 2 may not be linked to each other,

X11may be N or C(R14), X12may be N or C(R17), X13may be N or C(R18), and X14may be N or C(R19);

X15may be N or C(R20) when a14 is 0, and X15may be C when a14 is not 0,

X19may be C(R27)(R28) when a14 is 0, and X19may be C(R27) when a14 is not 0,

R15and R11, R15and R12, and/or R15and R13may optionally be linked to form a substituted or unsubstituted C5-C60carbocyclic group or a substituted or unsubstituted C1-C60heterocyclic group,

b11 to b13 may each independently be an integer from 1 to 8,

*, *′, and *″ each indicate a binding site to a neighboring atom.

According to another embodiment, an organic light-emitting device includes: a first electrode; a second electrode facing the first electrode; and an organic layer between the first electrode and the second electrode and including an emission layer, wherein the organic layer further includes at least one of the organometallic compound represented by Formula 1 or 2.

DETAILED DESCRIPTION

The present disclosure will now be described more fully with reference to exemplary embodiments. The disclosure may, however, be embodied in many different forms and should not be construed as being limited to the embodiments set forth herein; rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the concept of the disclosure to those skilled in the art. Enhancements, features, and how to achieve them of the present invention will become apparent by reference to the embodiment that will be described later in more detail, together with the accompanying drawings. This invention may, however, be embodied in many different forms and should not be limited to the exemplary embodiments.

Hereinafter, embodiments are described in more detail by referring to the attached drawings, and in the drawings, like reference numerals denote like elements, and a redundant explanation thereof will not be provided herein.

It will be further understood that the terms “comprises” and/or “comprising” as used herein specify the presence of stated features or components, but do not preclude the presence or addition of one or more other features or components.

It will be understood that when a layer, region, or component is referred to as being “on” or “onto” another layer, region, or component, it may be directly or indirectly formed on the other layer, region, or component. That is, for example, intervening layers, regions, or components may be present.

Sizes of components in the drawings may be exaggerated for convenience of explanation. In other words, because sizes and thicknesses of components in the drawings are arbitrarily illustrated for convenience of explanation, the following embodiments of the present disclosure are not limited thereto. Also, any numerical range recited herein is intended to include all sub-ranges of the same numerical precision subsumed within the recited range. For example, a range of “1.0 to 10.0” is intended to include all subranges between (and including) the recited minimum value of 1.0 and the recited maximum value of 10.0, that is, having a minimum value equal to or greater than 1.0 and a maximum value equal to or less than 10.0, such as, for example, 2.4 to 7.6. Any maximum numerical limitation recited herein is intended to include all lower numerical limitations subsumed therein and any minimum numerical limitation recited in this specification is intended to include all higher numerical limitations subsumed therein. Accordingly, Applicant reserves the right to amend this specification, including the claims, to expressly recite any sub-range subsumed within the ranges expressly recited herein.

According to an embodiment of the present disclosure, an organometallic compound is represented by Formula 1 or 2:

In one embodiment, M11may be selected from Pt, Pd, Cu, Ag, and Au.

For example, M11may be Pt, Pd, or Au, but embodiments of the present disclosure are not limited thereto.

In Formulae 1 and 2, A1to A13may each independently be selected from a C5-C60carbocyclic group and a C1-C60heterocyclic group, wherein A11in Formula 1 is not represented by

In one or more embodiments, A11to A13may each independently be selected from groups represented by Formulae 3-1(1) to 3-1(31) and 3-2(1) to 3-2(19):

In Formulae 3-1(1) to 3-1(31) and 3-2(1) to 3-2(19),

R31and R32may each independently be defined the same as R11in Formulae 1 and 2,

b32 may be 1 or 2,

* indicates a binding site to M11, and

*′ and *″ each indicate a binding site to a neighboring atom.

For example, A11to A13may each independently be selected from groups represented by Formulae 3-1(1) to 3-1(5) and 3-2(1) to 3-2(4), but embodiments of the present disclosure are not limited thereto.

In one embodiment, A11to A13may each independently be selected from groups represented by Formulae 3-1(1), 3-1(4), 3-2(1), and 3-2(3), but embodiments of the present disclosure are not limited thereto.

In one embodiment, A11may be a group represented by Formula 3-1(1) or 3-2(1), and A12and A13may each independently be a group represented by Formula 3-1(1), 3-2(1), or 3-2(3), but embodiments of the present disclosure are not limited thereto.

In one embodiment, R31and R32may each independently be selected from:

a C1-C20alkyl group and a C1-C20alkoxy group, each substituted with at least one selected from deuterium, —F, —Cl, —Br, —I, a cyano group, a phenyl group, and a biphenyl group;

In one or more embodiments, R31and R32may each independently be selected from:

In Formulae 1 and 2, Y11to Y13may each independently be selected from carbon atom (C) and nitrogen atom (N).

In one embodiment, Y11and Y12may each be C, and Y13may be N;

Y12and Y13may each be C, and Y11may be N; or

For example, Y12and Y13may each be C, and Y11may be N, but embodiments of the present disclosure are not limited thereto.

In Formulae 1 and 2, B11to B14may each independently be selected from a single bond, O, and S.

In one embodiment, B11to B14may each be a single bond.

In one or more embodiments, B11to B14may each be a single bond,

a bond between M11and Y11and a bond between M11and Y12may each be a covalent bond, and a bond between M11and Y13may be a coordinate bond;

a bond between M11and Y11and a bond between M11and Y13may each be a covalent bond, and a bond between M11and Y12may be a coordinate bond; or

a bond between M11and Y12and a bond between M11and Y13may each be a covalent bond, and a bond between M11and Y11may be a coordinate bond.

For example, B11to B14may each be a single bond, the bond between M11and Y12and the bond between M11and Y13may each be a covalent bond, and a bond between M11and Y11may be a coordinate bond, but embodiments of the present disclosure are not limited thereto.

In one or more embodiments, L11to L14may each independently be selected from a single bond, *—O—*′, and *—N(R15)—*′.

In one or more embodiments, L11and L12may each independently be selected from *—O—*′ and *—N(R15)—*′, and L13and L14may each independently be selected from a single bond, *—O—*′, and *—N(R15)—*′.

In Formulae 1 and 2, a11, a12, and a14 may each independently be an integer from 0 to 3, and a13 may be an integer from 1 to 3. At least two of a11, a12, and a14 may each independently be an integer from 1 to 3.

When a11 is 0, A11and A12may not be linked to each other, when a12 is 0, A12and A13may not be linked to each other, when a13 is 0, A13and a nitrogen atom (N) may not be linked to each other, and when a14 is 0, A11and X15in Formula 1 and A11and X19in Formula 2 may not be linked to each other.

a11 indicates the number of L11(s), wherein, when a11 is two or more, two or more L11(s) may be identical to or different from each other. a12 indicates the number of L12(s), wherein, when a12 is two or more, two or more L12(s) may be identical to or different from each other. a13 indicates the number of L13(s), wherein, when a13 is two or more, two or more L13(s) may be identical to or different from each other. a14 indicates the number of L14(s), wherein, when a14 is two or more, two or more L14(s) may be identical to or different from each other.

In one embodiment, a11 to a13 may each be 1, and a14 may be 0;

a12 to a14 may each be 1, and a11 may be 0; or

a11, a13, and a14 may each be 1, and a12 may be 0.

In one or more embodiments, a11 to a13 may each be 1, and a14 may be 0.

In one or more embodiments, a11 to a13 may each be 1, a14 may be 0, L11and L12may each independently be selected from *—O—*′ and *—N(R15)—*′, and L13may be a single bond.

In Formulae 1 and 2, X11may be N or C(R14), X12may be N or C(R17), X13may be N or C(R18), and X14may be N or C(R19),

X15may be N or C(R20) when a14 is 0, and X15may be C when a14 is not 0,

X16may be C(R21)(R22), X17may be C(R23)(R24), and X18may be C(R25)(R26), and

X19may be C(R27)(R28) when a14 is 0, and X19may be C(R27) when a14 is not 0.

In one embodiment, in Formula 1, X12may be C(R17), X13may be C(R18), and X14may be C(R19), and

X15may be C(R20) when a14 is 0, and X15may be C when a14 is not 0.

Here, R15and R11; R15and R12; and/or R15and R13may optionally be linked to form a substituted or unsubstituted C5-C60carbocyclic group or a substituted or unsubstituted C1-C60heterocyclic group. For example, when L11is *—N(R15)—*′, R15may optionally be linked with R11to form a substituted or unsubstituted C5-C60carbocyclic group or a substituted or unsubstituted C1-C60heterocyclic group.

In one embodiment, R11to R28may each independently be selected from:

a C1-C20alkyl group and a C1-C20alkoxy group, each substituted with at least one selected from deuterium, —F, —Cl, —Br, —I, a cyano group, a phenyl group, and a biphenyl group;

In Formulae 1 and 2, b11 to b13 may each independently be an integer from 1 to 8.

b11 indicates the number of R11(s), wherein, when b11 is two or more, two or more R11(s) may be identical to or different from each other. b12 indicates the number of R12(s), wherein, when b12 is two or more, two or more R12(s) may be identical to or different from each other. b13 indicates the number of R13(s), wherein, when b13 is two or more, two or more R13(s) may be identical to or different from each other.

In one embodiment, L11may be *—C(R15)(R16)—*′, *—N(R15)—*′, or *—Si(R15)(R16)—*′, and

R15and R11may be linked to form a substituted or unsubstituted C5-C60carbocyclic group or a substituted or unsubstituted C1-C60heterocyclic group, or R15and R12may be linked to form a substituted or unsubstituted C5-C60carbocyclic group or a substituted or unsubstituted C1-C60heterocyclic group.

In one or more embodiments, L11may be *—N(R15)—*′,

R15and R11may be linked to form a substituted or unsubstituted C1-C60heterocyclic group, or R15and R12may be linked to form a substituted or unsubstituted C1-C60heterocyclic group.

In one embodiment, the organometallic compound may be represented by Formula 1-1 or 1-2:

In Formulae 1-1 and 1-2,

In one embodiment, the organometallic compound may be selected from Compounds 1 to 15, but embodiments of the present disclosure are not limited thereto:

The organometallic compound represented by Formula 1 or 2 may include at least one imidazopyridine ring or tetrahydroimidazopyridine ring in a tetradentate ligand. A binding site of the imidazopyridine ring or the tetrahydroimidazopyridine ring and the core metal may be a carbene. Therefore, lowest unoccupied molecular orbital (LUMO) energy of the organometallic compound may increase, and an emission wavelength may be shifted to a short wavelength, thereby emitting blue light having high color purity.

In addition, N—C bond between a nitrogen atom of a carbene and a substituent linked to the nitrogen atom is low in chemical and electrical stability and thus may be easily decomposed. Therefore, when a compound having the carbene structure is utilized in the organic light-emitting device, the lifespan of the organic light-emitting device may be shortened. The organometallic compound represented by Formula 1 or 2 may include a structure in which the substituent linked to the nitrogen atom of the carbene is linked to an another adjacent substituent to form a condensed ring, for example, an imidazopyridine ring or a tetrahydroimidazopyridine ring. In addition, the nitrogen atom of the carbene may be linked to an adjacent ring linked to the core metal, for example, ring A13. That is, the organometallic compound represented by Formula 1 or 2 may suppress the decomposition of the N—C bond between the nitrogen atom of the carbene and the substituent linked to the nitrogen atom. Therefore, an electronic device, for example, an organic light-emitting device, which includes the organometallic compound, may have a low driving voltage, high efficiency, high luminance, and a long lifespan.

The organometallic compound represented by Formula 1 or 2 may be synthesized utilizing suitable (e.g., known) organic synthesis methods.

The organometallic compound represented by Formulae 1 or 2 may be utilized between a pair of electrodes of an organic light-emitting device. For example, the organometallic compound may be included in the emission layer. The organometallic compound included in the emission layer may act as a dopant.

According to another embodiment, an organic light-emitting device includes: a first electrode; a second electrode facing the first electrode; and an organic layer between the first electrode and the second electrode and including an emission layer, wherein the organic layer includes at least one of the organometallic compound represented by Formula 1 or 2.

The expression “(an organic layer) includes at least one of organometallic compounds” as used herein may include a case in which “(an organic layer) includes the same (e.g., identical) organometallic compounds represented by Formula 1 or 2” and a case in which “(an organic layer) includes two or more different organometallic compounds represented by Formula 1 or 2.”

For example, the organic layer may include, as the organometallic compound, only Compound 1. In this regard, Compound 1 may exist in an emission layer of the organic light-emitting device. In one or more embodiments, the organic layer may include, as the organometallic compound, Compound 1 and Compound 2. In this case, Compound 1 and Compound 2 may be present in the same layer (for example, both Compound 1 and Compound 2 may be present in the emission layer), or may be on different layers (for example, Compound 1 may be present in the emission layer and Compound 2 may be present in the electron transport layer).

In one embodiment, the emission layer may include the organometallic compound.

In one or more embodiments, the emission layer may include (e.g., consist of) the organometallic compound or may include the organometallic compound and a host, and an amount of the organometallic compound in the emission layer may be in a range of about 0.01 parts by weight to about 50 parts by weight based on 100 parts by weight of the emission layer.

In one embodiment, the host may include two different hosts.

A weight ratio of the two different hosts may be in a range of 90:10 to 10:90. For example, the weight ratio of the two different hosts may be in a range of 80:20, 70:30, 60:40, 50:50, 40:60, 30:70, or 20:80. For example, a weight ratio of the first compound to the second compound may be 50:50, but embodiments of the present disclosure are not limited thereto.

In one embodiment, the host may include a first host and a second host, the first host may include a carbazole-containing host or a silyl-containing host, and the second host may include a phosphine oxide-containing host.

In one embodiment, the emission layer may include the organometallic compound, and the emission layer may emit blue light. For example, the emission layer may emit blue light having a maximum emission wavelength of about 430 nm to about 490 nm, but embodiments of the present disclosure are not limited thereto.

In one embodiment, the first electrode may be an anode, the second electrode may be a cathode, 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 at least one selected from a hole injection layer, a hole transport layer, a buffer layer, an emission auxiliary layer, and an electron blocking layer, and the electron transport region may include at least one selected from a hole blocking layer, an electron transport layer, and an electron injection layer.

In one embodiment, at least one of the emission layer, the hole blocking layer, the electron transport layer, and the electron injection layer may include a phosphine oxide-containing compound.

In one or more embodiments, at least one of the emission layer, the hole blocking layer, the electron transport layer, and the electron injection layer may include a silyl-containing compound.

In one embodiment, the electron transport region may include a hole blocking layer, and the hole blocking layer may include a phosphine oxide-containing compound.

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 the organic light-emitting device. A material included in the “organic layer” is not limited to an organic material.

Description of FIG.1

FIG. 1is a schematic 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, the 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.

First Electrode110

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

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

The first electrode110may be a reflective electrode, a semi-transmissive electrode, or a transmissive electrode. When the first electrode110is a transmissive electrode, a material for forming the first electrode may be selected from indium tin oxide (ITO), indium zinc oxide (IZO), tin oxide (SnO2), zinc oxide (ZnO), and any combinations thereof, but embodiments of the present disclosure are not limited thereto. When the first electrode110is a semi-transmissive electrode or a reflective electrode, as a material for forming the first electrode110, magnesium (Mg), silver (Ag), aluminum (Al), aluminum-lithium (Al—Li), calcium (Ca), magnesium-indium (Mg—In), magnesium-silver (Mg—Ag), or any combination thereof may be utilized. However, the material for forming the first electrode110is not limited thereto.

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

Hole Transport Region in Organic Layer150

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 single layer 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 for each structure, constituting layers are sequentially stacked from the first electrode110in this stated order, but the structure of the hole transport region is not limited thereto.

In Formulae 201 and 202,

xa1 to xa4 may each independently be an integer of 0 to 3,

xa5 may be an integer of 1 to 10,

For example, in Formula 202, R201and R202may optionally be linked via a single bond, a dimethyl-methylene group, or a diphenyl-methylene group, and R203and R204may optionally be linked via a single bond, a dimethyl-methylene group, or a diphenyl-methylene group.

In one or more embodiments, in Formulae 201 and 202,

L201to L205may each independently be selected from:

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

In one or more embodiments, R201to R204and Q201may each independently be selected from:

Q31to Q33may respectively be defined the same as those described above in connection with L201to L205.

In one or more embodiments, in Formula 201, at least one selected from R201to R203may each independently be selected from:

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

In one or more embodiments, in Formula 202, at least one selected from R201to R204may be selected from:

a carbazolyl group; and

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

In one embodiment, the compound represented by Formula 202 may be represented by Formula 202A:

In one embodiment, the compound represented by Formula 202 may be represented by Formula 202A-1:

L201to L203, xa1 to xa3, xa5, and R202to R204may respectively be defined the same as those described above in connection with Formulae 201 and 202,

R211and R212may respectively be defined the same as described in connection with R203in Formulae 201 and 202.

The hole transport region may include at least one compound selected from Compounds HT1 to HT39, but embodiments of the present disclosure are not limited thereto:

The emission auxiliary layer may increase light-emission efficiency by compensating for an optical resonance distance according to the wavelength of light emitted by an emission layer, and the electron blocking layer may block 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. p-dopant

In one embodiment, the p-dopant may have a lowest unoccupied molecular orbital (LUMO) level of −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.

For example, the p-dopant may include at least one selected from:

a metal oxide, such as tungsten oxide or molybdenum oxide;

a compound represented by Formula 221,

In Formula 221,

Emission Layer in Organic Layer150

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

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

Host in Emission Layer

In one or more embodiments, the host may include a compound represented by Formula 301 below.

In Formula 301,

L301may each independently (i.e., when two or more L301s are included) 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,

xb21 may be an integer from 1 to 5, and

In one embodiment, Ar301in Formula 301 may be selected from:

When xb111 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 301-2:

In Formulae 301-1 and 301-2,

A301to A304may each independently be selected from a benzene, a naphthalene, a phenanthrene, a fluoranthene, a triphenylene, a pyrene, a chrysene, a pyridine, a pyrimidine, an indene, a fluorene, a spiro-bifluorene, a benzofluorene, a dibenzofluorene, an indole, a carbazole, benzocarbazole, dibenzocarbazole, a furan, a benzofuran, a dibenzofuran, a naphthofuran, a benzonaphthofuran, dinaphthofuran, a thiophene, a benzothiophene, a dibenzothiophene, a naphthothiophene, a benzonaphthothiophene, and a dinaphthothiophene,

xb22 and xb23 may each independently be 0, 1, or 2,

L301, xb1, R301, and Q31to Q33may respectively be defined the same as those described above in connection with Formula 301,

L302to L304may respectively be defined the same connection with L301in Formula 301,

xb2 to xb4 may respectively be defined the same as described in connection with xb1 in Formula 301, and

R302to R304may respectively be defined the same as described in connection with R301in Formula 301,

For example, in Formulae 301, 301-1, and 301-2, L301to L304may each independently be selected from:

Q31to Q33may respectively be defined the same as those described above in connection with Ar301in Formula 301.

In one embodiment, in Formulae 301, 301-1, and 301-2, R301to R304may each independently be selected from:

Q31and Q33may respectively be defined the same as those described above.

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

Phosphorescent Dopant Included in Emission Layer in Organic Layer150

The phosphorescent dopant may include an organometallic compound represented by Formula 1 or 2.

In addition, the phosphorescent dopant may further include an organometallic complex represented by Formula 401:

In Formulae 401 and 402,

L401may be selected from ligands 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 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 selected from a C5-C60carbocyclic group or a C1-C60heterocyclic group,

X406may be a single bond, O, or S,

xc11 and xc12 may each independently be an integer of 0 to 10, and

* and *′ in Formula 402 each indicate a binding site to M of Formula 401.

In one or more embodiments, in Formula 402, i) X401may be nitrogen, and X402may be carbon, or ii) X401and X402may each be nitrogen at the same time.

In one or more embodiments, in Formula 402, R401and R402may each independently be selected from:

a C1-C20alkyl group, and a C1-C20alkoxy group, each substituted with at least one selected from deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, an amidino group, a hydrazino group, a hydrazono group, a phenyl group, a naphthyl group, a cyclopentyl group, a cyclohexyl group, an adamantanyl group, a norbornanyl group, and a norbornenyl group;

Q401to Q403may each independently be selected from a C1-C10alkyl group, a C1-C10alkoxy group, a phenyl group, a biphenyl group, and a naphthyl group, but embodiments of the present disclosure are not limited thereto.

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 via X407, which is a linking group, or two A402(s) in two or more L401(S) may optionally be linked via X408, which is a linking group (see Compounds PD1 to PD4 and PD7). X407and X408may each independently be a single bond, *—O—*′, *—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.

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:

Fluorescent Dopant in Emission Layer

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

The fluorescent dopant may include a compound represented by Formula 501 below.

In Formula 501,

xd1 to xd3 may each independently be an integer of 0 to 3;

xd4 may be an integer of 1 to 6.

In one embodiment, Ar501in Formula 501 may be selected from:

In one or more embodiments, L501to L503in Formula 501 may each independently be selected from:

In one or more embodiments, in Formula 501, R501and R502may each independently be selected from:

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

For example, 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 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 for each structure, constituting layers 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-depleted nitrogen-containing ring.

The term “π electron-depleted nitrogen-containing ring” as used herein indicates a C1-C60heterocyclic group having at least one *—N=*′ moiety as a ring-forming moiety.

Examples of the π electron-depleted nitrogen-containing ring include an imidazole, a pyrazole, a thiazole, an isothiazole, an oxazole, an isoxazole, a pyridine, a pyrazine, a pyrimidine, a pyridazine, an indazole, a purine, a quinoline, an isoquinoline, a benzoquinoline, a phthalazine, a naphthyridine, a quinoxaline, a quinazoline, a cinnoline, a phenanthridine, an acridine, a phenanthroline, a phenazine, a benzimidazole, an isobenzothiazole, a benzoxazole, an isobenzoxazole, a triazole, a tetrazole, an oxadiazole, a triazine, a thiadiazol, an imidazopyridine, an imidazopyrimidine, and an azacarbazole, but embodiments of the present disclosure are not limited thereto.

For example, the electron transport region may include a compound represented by Formula 601:

In Formula 601,

L601may each independently (i.e., when two or more L601s are included) 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,

xe21 may be an integer from 1 to 5.

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

In one embodiment, ring Ar601in Formula 601 may be selected from:

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

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

In one or more embodiments, a 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 selected from X614to X616may be N,

L611to L613may each independently be the same as described in connection with L601in Formula 601,

xe611 to xe613 may each independently be defined the same as described in connection with xe1 in Formula 601,

R611to R613may each independently be the same as described in connection with R601in Formula 601, and

In one embodiment, L601and L611to L613in Formulae 601 and 601-1 may each independently be selected from:

In one or more embodiments, R601and R611to R613in Formula 601 and 601-1 may each independently be selected from:

—S(═O)2(Q601) and —P(═O)(Q601)(Q602), and

Q601and Q602may respectively be defined the same as those described above in connection with R601in Formula 601.

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 thickness of the buffer layer, the hole blocking layer, or the electron controlling layer may each independently be in a range of 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, the electron blocking layer may have excellent electron blocking characteristics or electron control characteristics without a substantial increase in driving voltage.

The metal-containing material may include at least one selected from alkali metal complex and alkaline earth-metal complex. The alkali metal complex may include a metal ion selected from a Li ion, a Na ion, a K ion, a Rb ion, and a Cs ion, and the alkaline earth-metal complex may include a metal ion selected from a Be ion, a Mg ion, a Ca ion, a Sr ion, and a 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 diphenylthiadiazol, 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 that facilitates injection of electrons from the second electrode190. The electron injection layer may directly contact the second electrode190.

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 combinations thereof.

The alkali metal may be selected from Li, Na, K, Rb, and Cs. In one 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 Sc, Y, Ce, Tb, Yb, and 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, or K2O, and alkali metal halides, such as LiF, NaF, CsF, KF, LiI, NaI, CsI, or KI. In one 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.

The alkaline earth-metal compound may be selected from alkaline earth-metal oxides, such as BaO, SrO, CaO, BaxSr1-xO (0<x<1), or BaxCa1-xO (0<x<1). In one 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 one 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 diphenylthiadiazol, 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 include (e.g., 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 combinations 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 an 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 combinations thereof may be homogeneously or non-homogeneously dispersed in a matrix including the organic material.

The second electrode190may be disposed on the organic layer150having such a structure. The second electrode190may be a cathode that is an electron injection electrode, and in this regard, a material for forming the second electrode190may be a material having a low work function, and such a material may be metal, alloy, an electrically conductive compound, or a combination thereof.

The second electrode190may include at least one selected from lithium (Li), silver (Si), 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, which are 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, which are sequentially stacked in this stated order; and 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. 2 to 4, 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 external luminescent efficiency according to the principle of constructive interference.

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

At least one selected from the first capping layer210and the second capping layer220may each independently include at least one material selected from carbocyclic compounds, heterocyclic compounds, amine-based compounds, porphyrine derivatives, phthalocyanine derivatives, a naphthalocyanine derivatives, alkali metal complexes, and alkaline earth-based 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 one embodiment, at least one selected from the first capping layer210and the second capping layer220may each independently include an amine-based compound.

In one embodiment, at least one selected from the first capping layer210and the second capping layer220may each independently include the compound represented by Formula 201 and/or the compound represented by Formula 202.

In one or more embodiments, at least one selected from 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 according to an embodiment has been described in connection withFIGS. 1-4. However, embodiments of the present disclosure are not limited thereto.

Layers constituting the hole transport region, the emission layer, and layers constituting the electron transport region may be formed in a certain region utilizing 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.

When layers constituting the hole transport region, the emission layer, and layers constituting the electron transport region are formed by vacuum deposition, the deposition may be performed at a deposition temperature of about 100° C. to about 500° C., a vacuum degree of about 1008 torr to about 10−3torr, and a deposition rate of about 0.01 Å/sec to about 100 Å/sec by taking into account a material to be included in a layer to be formed, and the structure of a layer to be formed.

General Definition of Substituents

The term “C1-C60alkoxy group” as used herein refers to a monovalent group represented by —OA101(wherein A101represents the C1-C60alkyl group), and non-limiting examples thereof may include a methoxy group, an ethoxy group, and an isopropyloxy group.

The term “C1-C10heterocycloalkyl group” as used herein refers to a monovalent saturated monocyclic group having at least one heteroatom selected from N, O, Si, P, and S as a ring-forming atom in addition to 1 to 10 carbon atoms, and non-limiting examples thereof may include a 1,2,3,4-oxatriazolidinyl group, a tetrahydrofuranyl group, a tetrahydrothiophenyl group. The term “C1-C10heterocycloalkylene group” as used herein refers to a divalent group having the same structure as the C1-C10heterocycloalkyl group.

The term “C6-C60aryloxy group” as used herein refers to a group represented by —OA102(wherein A102represents the C6-C60aryl group), and the term “C6-C60arylthio group” as used herein refers to a group represented by —SA103(wherein A103represents the C6-C60aryl group).

The term “monovalent non-aromatic condensed polycyclic group” as used herein refers to a monovalent group (for example, having 8 to 60 carbon atoms) having two or more rings condensed with each other, only carbon atoms as ring-forming atoms, and no aromaticity in its entire molecular structure. An example of the monovalent non-aromatic condensed polycyclic group may be a fluorenyl group. The term “divalent non-aromatic condensed polycyclic group” as used herein refers to a divalent group having the same structure as the monovalent non-aromatic condensed polycyclic group.

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 N, O, Si, P, and S, other than carbon atoms, as a ring-forming atom, and no aromaticity in its entire molecular structure. An example of the monovalent non-aromatic condensed heteropolycyclic group may be a carbazolyl group. The term “divalent non-aromatic condensed heteropolycyclic group” as used herein refers to a divalent group having 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 having 5 to 60 carbon atoms in which a ring-forming atom includes carbon atom only. The C5-C60carbocyclic group may be an aromatic carbocyclic group or a non-aromatic carbocyclic group. The C5-C60carbocyclic group may be a ring (e.g., a neutral 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 the same structure as the C1-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 a range of 1 to 60).

The term “Ph” as used herein may refer to a phenyl group; the term “Me”, as used herein, may refer to a methyl group; the term “Et”, as used herein, may refer to an ethyl group; the term “ter-Bu” or “But”, as used herein, may refer to a tert-butyl group; and the term “OMe” as used herein may refer to a methoxy group.

The term “a terphenyl group” as used herein may refer to “a phenyl group substituted with a biphenyl group”. The term “a terphenyl group” as used herein may refer to “a C6-C60aryl group substituted with a C6-C60aryl group” belonging to “the substituted phenyl group”.

*, *′, and *″ used herein, unless defined otherwise, each indicate a binding site to a neighboring atom in the corresponding formulae.

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 utilized instead of A” utilized in describing Synthesis Examples refers to that an identical molar equivalent of B was utilized in place of A.

EXAMPLES

Synthesis Example 1: Synthesis of Compound 1

(1) Synthesis of Intermediate [1-A]

5.00 g (27.30 mmol) of 2-hydroxycarbazole, 3.25 ml (27.30 mmol) of benzyl bromide, and 3.77 g (27.30 mmol) of potassium carbonate were dissolved in dimethylformamide and stirred at room temperature for 2 days. Distilled water was added to the reaction mixture and stirred for 10 minutes. The resulting precipitate was filtered and washed with distilled water (3 times) and ethyl acetate (1 time). The precipitate was dried under reduced pressure to obtain 6.00 g of Intermediate [1-A].

(2) Synthesis of Intermediate [1-B]

4.00 g (15.00 mmol) of the synthesized Intermediate [1-A], 0.28 g (0.30 mmol) of Pd2(dba)3, 0.18 g (0.60 mmol) of JohnPhos ((2-biphenyl)di-tert-butylphosphine), 2.31 g (24.00 mmol) of sodium tert-butoxide, and 1.72 g (18.00 mmol) of 2-bromopyridine were suspended in 45 ml of toluene, heated to a temperature of 100° C., and stirred for 3 days. The reaction mixture was cooled to room temperature and concentrated under reduced pressure. The concentrate obtained therefrom was purified by column chromatography (ethyl acetate:n-hexane=10:1 to 5:1) to obtain 4.55 g of Intermediate [1-B].

(3) Synthesis of Intermediate [1-C]

4.55 g (13.00 mmol) of the synthesized Intermediate [1-B] and 5.78 g (39.0 mmol) of pentamethylbenzene were dissolved in 100 ml of methylene chloride, cooled to a temperature of 0° C., and 32.5 ml of BCl3(1 M methylene chloride solution, 32.5 mmol) was slowly added dropwise thereto. The reaction mixture was stirred for 1.5 hours. The reaction was terminated by adding distilled water, and the reaction product was diluted with methylene chloride. The diluted solution was neutralized by adding saturated sodium bicarbonate solution, and an organic layer was extracted therefrom. The organic layer was dried utilizing sodium sulfate, filtered, and dried under reduced pressure. The concentrate obtained therefrom was purified by column chromatography (ethylacetate:n-hexane=10:1 to 3:1) to obtain 2.79 g of Intermediate [1-C].

(4) Synthesis of Intermediate [1-D]

2.50 g of the synthesized Intermediate [1-C], 5.0 g of tert-butyl(3-bromophenyl)carbamate, and 0.10 g of iodine copper were suspended in 150 ml of dimethylformamide solvent, heated to a temperature of 160° C., and stirred for 12 hours. The reaction mixture was concentrated under reduced pressure, and an organic layer was extracted therefrom utilizing methylene chloride and distilled water. The organic layer was dried utilizing magnesium sulfate, filtered, and concentrated under reduced pressure. The concentrate obtained therefrom was purified by column chromatography to obtain 2.00 g of Intermediate [1-D].

(5) Synthesis of Intermediate [1-E]

2.00 g of the synthesized Intermediate [1-D] was dissolved in 150 ml of methylene chloride, and 1.5 ml of trifluoroacetic acid was added thereto at a temperature of 0° C. and stirred at room temperature for 5 hours. After the reaction was completed, distilled water was added to the reaction product, and an organic layer was extracted therefrom. The organic layer was dried utilizing magnesium sulfate, filtered, and concentrated under reduced pressure to obtain 1.50 g of Intermediate [1-E].

(6) Synthesis of Intermediate [1-F]

24.5 g (50.0 mmol) of the synthesized Intermediate [1-E] was dissolved in 50 ml of methylene chloride, concentrated hydrochloric acid was added dropwise thereto, and the reaction mixture was solidified. The resulting solid was filtered, washed with diethylether, and dried. The solid was dissolved in 100 ml of ethanol, and 2.1 ml of 37% formaldehyde aqueous solution and 4.8 ml of 2-pyridine carboxyaldehyde were added thereto. The precipitate obtained after stirring at room temperature for 24 hours was filtered, washed with diethylether, and dried. The dried solid was dissolved in a mixed solution of methanol/distilled water and 50% aqueous solution of tetrafluoroboronic acid, and the produced solid was filtered and washed with diethylether to obtain 22.0 g of Intermediate [1-F].

(7) Synthesis of Compound 1

The synthesized Intermediate [1-F] (1.0 eq) and potassium tetrachloroplatinate (K2PtCl4) (1.1 eq), and tetrabutylammonium bromide (0.1 eq) were dissolved in acetic acid (0.1M) and stirred at a temperature of 120° C. for 72 hours. The reaction mixture was cooled to room temperature, and an organic layer was extracted therefrom three times utilizing dichloromethane and water. The extracted organic layer was dried utilizing magnesium sulfate and concentrated, and column chromatography was utilized to obtain Compound 1 (yield: 20%).

Synthesis Example 2: Synthesis of Compound 2

Compound 2 was obtained in the same manner as in Synthesis Example 1, except that 2-chloro-4-tert-butylpyridine was utilized instead of 2-bromopyridine.

Synthesis Example 3: Synthesis of Compound 3

Compound 3 was synthesized in the same manner as in Synthesis Example 1, except that 2-bromo-4-methylpyridine was utilized instead of 2-bromopyridine.

Synthesis Example 4: Synthesis of Compound 4

Compound 4 was synthesized in the same manner as in Synthesis Example 1, except that tert-butyl(5-bromopyridin-3-yl)carbamate was utilized instead of tert-butyl(3-bromophenyl)carbamate

Synthesis Example 5: Synthesis of Compound 5

Compound 4 was synthesized in the same manner as in Synthesis Example 1, except that 2-chloro-4-fluorobutylpyridine was utilized instead of 2-bromopyridine, and tert-butyl (5-bromopyridin-3-yl)carbamate was utilized instead of tert-butyl(3-bromophenyl)carbamate.

Synthesis Example 6: Synthesis of Compound 6

Compound 6 was obtained in the same manner as in Synthesis Example 1, except that 3-(pyridin-2-yloxy)phenol was utilized instead of Intermediate [1-C]

Synthesis Example 7: Synthesis of Compound 7

Compound 7 was obtained in the same manner as in Synthesis Example 1, except that 3-((4-(tert-butyl)pyridin-2-yl)oxy)phenol was utilized instead of Intermediate [1-C].

Synthesis Example 8: Synthesis of Compound 8

Compound 8 was obtained in the same manner as in Synthesis Example 1, except that 3-((4-methylpyridin-2-yl)oxy)phenol was utilized instead of Intermediate [1-C].

Synthesis Example 9: Synthesis of Compound 9

Compound 9 was obtained in the same manner as in Synthesis Example 1, except that tert-butyl(5-bromopyridin-3-yl)carbamate was utilized instead of Tert-butyl(3-bromophenyl)carbamate, and 3-(pyridin-2-yloxy)phenol was utilized instead of Intermediate [1-C].

Synthesis Example 10: Synthesis of Compound 10

Compound 10 was obtained in the same manner as in Synthesis Example 1, except that tert-butyl(5-bromopyridin-3-yl)carbamate was utilized instead of tert-butyl(3-bromophenyl)carbamate, and 3-((4-fluoropyridin-2-yl)oxy)phenol was utilized instead of Intermediate [1-C].

1H NMR and HR-EIMS of Compounds synthesized in Synthesis Examples 1 to 10 are shown in Table 1.

Synthesis methods of compounds other than Compounds synthesized according to Synthesis Examples 1 to 10 may also be easily recognized by those of ordinary skill in the art by referring to the synthesis mechanisms and source materials described above.

As a substrate and an ITO anode, a Corning glass substrate, on which 15 Ω/cm2(1,200 Å) ITO was formed, was cut into a size of 50 mm×50 mm×0.7 mm, sonicated with isopropyl alcohol and pure water each for 5 minutes, and then cleaned by exposure to ultraviolet rays and ozone for 30 minutes. Then, the glass substrate was provided to a vacuum deposition apparatus.

2-TNATA was vacuum-deposited on the ITO anode formed on the glass substrate to form a hole injection layer having a thickness of 600 Å, and NPB was vacuum-deposited on the hole injection layer to form a hole transport layer having a thickness of 300 Å.

BCPDS and POPCPA as a co-host (a weight ratio of BCPDS to POPCPA was 1:1) and Compound 1 (dopant) were co-deposited on the hole transport layer at a co-host to dopant weight ratio of 90:10 to form an emission layer having a thickness of 300 Å.

TSPO1 was deposited on the emission layer to form a hole blocking layer having a thickness of 50 Å, Alq3was deposited on the hole blocking layer to form an electron transport layer having a thickness of 300 Å, LiF was deposited on the electron transport layer to form an electron injection layer having a thickness of 10 Å, and Al was vacuum-deposited on the electron injection layer to form a cathode having a thickness of 3,000 Å, thereby completing the manufacture of an organic light-emitting device.

Examples 2 to 10 and Comparative Examples A to E

Organic light-emitting devices were manufactured substantially in the same manner as in Example 1, except that Compounds shown in Table 2 were each utilized instead of Compound 1 as a dopant in forming an emission layer.

Evaluation Example

The driving voltage, current density, luminance, luminescent efficiency, and maximum emission wavelength of the organic light-emitting devices manufactured according to Examples 1 to 10 and Comparative Examples A to E were measured by using Keithley SMU 236 and a luminance meter PR650, and results thereof are shown in Table 2. The half lifespan (T50) indicates an amount of time that lapsed when luminance was 50% of the initial luminance (100%) after driving an organic light-emitting device for the lapsed time.

Referring to Table 2, it is confirmed that the organic light-emitting devices of Examples 1 to 10 have a low driving voltage, high efficiency, and high color purity, as compared with those of the organic light-emitting devices of Comparative Examples A to E.

The organic light-emitting device including the organometallic compound may have a low driving voltage and high efficiency and may exhibit high color purity, thereby implementing high-quality organic light-emitting devices.