ORGANOMETALLIC COMPOUND AND ORGANIC LIGHT-EMITTING DEVICE INCLUDING THE SAME

CROSS-REFERENCE TO RELATED APPLICATION

This application claims priority to Korean Patent Application No. 10-2014-0054430, filed on May 7, 2014, in the Korean Intellectual Property Office, and all the benefits accruing therefrom under 35 U.S.C. §119, the content of which is incorporated herein in its entirety by reference.

BACKGROUND

1. Field

One or more embodiments relate to organometallic compounds and organic light-emitting devices including the same.

2. Description of the Related Art

Organic light emitting devices (OLEDs) are self-emission devices that have wide viewing angles, high contrast ratios, short response times, and excellent brightness, driving voltage, and response speed characteristics, and produce full-color images.

A typical organic light-emitting device includes an anode, a cathode, and an organic layer that is disposed between the anode and the cathode and includes an emission layer. A hole transport region may be disposed between the anode and the emission layer, and an electron transport region may be disposed between the emission layer and the cathode. Holes provided from the anode may move toward the emission layer through the hole transport region, and electrons provided from the cathode may move toward the emission layer through the electron transport region. Carriers, such as holes and electrons, are recombined in the emission layer to produce excitons. These excitons change from an excited state to a ground state, thereby generating light.

Various types of organic light emitting devices are known. However, there still remains a need in OLEDs having low driving voltage, high efficiency, high brightness, and long lifespan.

SUMMARY

One or more embodiments relate to novel organometallic compounds and organic light-emitting devices including the same.

Provided are organometallic compounds represented by Formulae 1 or 2, and L₁in Formula 1 is selected from a ligand represented by Formula 3A, a ligand represented by Formula 3B, a ligand represented by Formula 3C, and a ligand represented by Formula 3D:

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wherein in the formulae above,

M₁may be selected from Ir, Pt, Os, Ti, Zr, Hf, Eu, Tb, and Tm;

M₂is selected from Ir, Os, and Eu;

Y₁to Y₁₅are each independently C or N;

- CY₁is selected from a pyrrole, an imidazole, a pyrazole, a thiazole, an isothiazole, an oxazole, an isooxazole, a triazole, a pyrazine, a pyrimidine, a pyridazine, a quinoline, an isoquinoline, a benzoquinoline, a quinoxaline, a quinazoline, a benzoimidazole, a benzooxazole, an isobenzooxazole, a triazole, a tetrazole, an oxadiazole, and a triazine;

CY₃and CY₅to CY₁₃may be each independently a C₂-C₆₀heterocyclic group including at least one N;

CY₂and CY₄are each independently selected from a C₅-C₆₀carbocyclic group and a C₂-C₆₀heterocyclic group;

Y₁is linked to N by a single bond or a double bond,

Y₂is linked to C by a single bond or a double bond,

Y₃is linked to N by a single bond or a double bond,

Y₄is linked to C by a single bond or a double bond,

Y₅is linked to C by a single bond or a double bond,

Y₆is linked to N by a single bond or a double bond,

Y₇is linked to N by a single bond or a double bond,

Y₈is linked to N by a single bond or a double bond,

Y₉is linked to N by a single bond or a double bond,

Y₁₀is linked to N by a single bond or a double bond,

Y₁₁is linked to N by a single bond or a double bond,

Y₁₂is linked to N by a single bond or a double bond,

Y₁₃is linked to N by a single bond or a double bond,

Y₁₄is linked to N by a single bond or a double bond, and

Y₁₅is linked to N by a single bond or a double bond;

Z₁to Z₁₆may be each independently selected from a hydrogen, a deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, an amino group, an amidino group, a hydrazine group, a hydrazone group, a carboxylic acid group or a salt thereof, a sulfonic acid group or a salt thereof, a phosphoric acid group or a salt thereof, —SF₅, 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 C₂-C₁₀heterocycloalkyl group, a substituted or unsubstituted C₃-C₁₀cycloalkenyl group, a substituted or unsubstituted C₂-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 C₂-C₆₀heteroaryl group, a substituted or unsubstituted monovalent non-aromatic condensed polycyclic group, a substituted or unsubstituted monovalent non-aromatic condensed heteropolycyclic group, —N(Q₁)(Q₂), —Si(Q₃)(Q₄)(Q₅), and —B(Q₆)(Q₇);

a1 to a13 are each independently an integer selected from 1 to 5;

n1 is 1 or 2;

Z₉and Z₁₀in Formula 3A are not linked to each other to form a ring;

the organometallic compound represented by Formulae 1 or 2 is neutral;

at least one of substituents of the substituted C₁-C₆₀alkyl group, the substituted C₂-C₆₀alkenyl group, the substituted C₂-C₆₀alkynyl group, the substituted C₁-C₆₀alkoxy group, the substituted C₃-C₁₀cycloalkyl group, the substituted C₂-C₁₀heterocycloalkyl group, the substituted C₃-C₁₀cycloalkenyl group, the substituted C₂-C₁₀heterocycloalkenyl group, the substituted C₆-C₆₀aryl group, the substituted C₆-C₆₀aryloxy group, the substituted C₆-C₆₀arylthio group, the substituted C₂-C₆₀heteroaryl group, the substituted monovalent non-aromatic condensed polycyclic group, and the substituted monovalent non-aromatic condensed heteropolycyclic group may be selected from

a deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, an amino group, an amidino group, a hydrazine group, a hydrazone group, a carboxylic acid group or a salt thereof, a sulfonic acid group or a salt thereof, a phosphoric acid group or a salt thereof, a C₁-C₆₀alkyl group, a C₂-C₆₀alkenyl group, a C₂-C₆₀alkynyl group, and a C₁-C₆₀alkoxy group;

a C₃-C₁₀cycloalkyl group, a C₂-C₁₀heterocycloalkyl group, a C₃-C₁₀cycloalkenyl group, a C₂-C₁₀heterocycloalkenyl group, a C₆-C₆₀aryl group, a C₆-C₆₀aryloxy group, a C₆-C₆₀arylthio group, a C₂-C₆₀heteroaryl group, a monovalent non-aromatic condensed polycyclic group, and a monovalent non-aromatic condensed heteropolycyclic group, each substituted with at least one selected from a deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, an amino group, an amidino group, a hydrazine group, a hydrazone group, a carboxylic acid group or a salt thereof, a sulfonic acid group or a salt thereof, a phosphoric acid group or a salt thereof, a C₁-C₆₀alkyl group, a C₂-C₆₀alkenyl group, a C₂-C₆₀alkynyl group, a C₁-C₆₀alkoxy group, a C₃-C₁₀cycloalkyl group, a C₂-C₁₀heterocycloalkyl group, a C₃-C₁₀cycloalkenyl group, a C₂-C₁₀heterocycloalkenyl group, a C₆-C₆₀aryl group, a C₆-C₆₀aryloxy group, a C₆-C₆₀arylthio group, a C₂-C₆₀heteroaryl group, a monovalent non-aromatic condensed polycyclic group, a monovalent non-aromatic condensed heteropolycyclic group, —N(Q₂₁)(Q₂₂), —Si(Q₂₃)(Q₂₄)(Q₂₆) and —B(Q₂₆)(Q₂₇); and

—N(Q₃₁)(Q₃₂), —Si(Q₃₃)(Q₃₄)(Q₃₆), and —B(Q₃₆)(Q₃₇),

wherein Q₁to Q₇, Q₁₁to Q₁₇, Q₂₁to Q₂₇, and Q₃₁to Q₃₇may be each independently selected from a hydrogen, a C₁-C₆₀alkyl group, a C₂-C₆₀alkenyl group, a C₂-C₆₀alkynyl group, a C₁-C₆₀alkoxy group, a C₃-C₁₀cycloalkyl group, a C₂-C₁₀heterocycloalkyl group, a C₃-C₁₀cycloalkenyl group, a C₂-C₁₀heterocycloalkenyl group, a C₆-C₆₀aryl group, a C₆-C₆₀aryloxy group, a C₆-C₆₀arylthio group, a C₆-C₆₀heteroaryl group, a monovalent non-aromatic condensed polycyclic group, and a monovalent non-aromatic condensed heteropolycyclic group.

Another aspect provides an organic light-emitting device including:

a first electrode;

a second electrode; and

an organic layer disposed between the first electrode and the second electrode, wherein the organic layer includes an emission layer, and further includes at least one organometallic compound represented by Formula 1.

The organometallic compound may be included in the emission layer, the organometallic compound included in the emission layer may act as a dopant, and the emission layer may further include a host.

BRIEF DESCRIPTION OF THE DRAWINGS

These and/or other aspects will become apparent and more readily appreciated from the following description of the embodiments, taken in conjunction with the accompanying drawings in which:

FIG. 1 is a schematic view of an organic light-emitting device according to an embodiment;

FIG. 2 is a graph of intensity (arbitrary units, a. u.) versus mass-to-charge ratio m/z showing a mass spectrum of Compound 1;

FIG. 3 is a graph of intensity (arbitrary units, a. u.) versus mass-to-charge ratio m/z showing a mass spectrum of Compound 2;

FIGS. 4A and 4B are graphs of current (microamperes, mA) versus potential (volts, V) showing a cyclic voltammogram of Compound 1;

FIG. 5 is a graph of percent weight (percent, %) versus time (minutes, min) showing differential scanning calorimetry (DSC) data of Compound 1; and

FIG. 6 is a graph of intensity (arbitrary units, a. u.) versus wavelength (nanometers, nm) showing photoluminescent (PL) spectra of Compounds 1, 2, and 4.

DETAILED DESCRIPTION

Reference will now be made in detail to embodiments, examples of which are illustrated in the accompanying drawings, wherein like reference numerals refer to like elements throughout. In this regard, the present embodiments may have different forms and should not be construed as being limited to the descriptions set forth herein. Accordingly, the embodiments are merely described below, by referring to the figures, to explain aspects of the present description. As used herein, the term “and/or” includes any and all combinations of one or more of the associated listed items. Expressions such as “at least one of,” when preceding a list of elements, modify the entire list of elements and do not modify the individual elements of the list.

It will be understood that when an element is referred to as being “on” another element, it can be directly in contact with the other element or intervening elements may be present therebetween. In contrast, when an element is referred to as being “directly on” another element, there are no intervening elements present.

It will be understood that, although the terms first, second, third etc. may be used herein to describe various elements, components, regions, layers, and/or sections, these elements, components, regions, layers, and/or sections should not be limited by these terms. These terms are only used to distinguish one element, component, region, layer, or section from another element, component, region, layer, or section. Thus, a first element, component, region, layer, or section discussed below could be termed a second element, component, region, layer, or section without departing from the teachings of the present embodiments.

The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting. As used herein, the singular forms “a,” “an,” and “the” are intended to include the plural forms as well, unless the context clearly indicates otherwise.

It will be further understood that the terms “comprises” and/or “comprising,” or “includes” and/or “including” when used in this specification, specify the presence of stated features, regions, integers, steps, operations, elements, and/or components, but do not preclude the presence or addition of one or more other features, regions, integers, steps, operations, elements, components, and/or groups thereof.

Spatially relative terms, such as “beneath,” “below,” “lower,” “above,” “upper” and the like, may be used herein for ease of description to describe one element or feature's relationship to another element(s) or feature(s) as illustrated in the figures. It will be understood that the spatially relative terms are intended to encompass different orientations of the device in use or operation in addition to the orientation depicted in the figures. For example, if the device in the figures is turned over, elements described as “below” or “beneath” other elements or features would then be oriented “above” the other elements or features. Thus, the exemplary term “below” can encompass both an orientation of above and below. The device may be otherwise oriented (rotated 90 degrees or at other orientations) and the spatially relative descriptors used herein interpreted accordingly.

“About” or “approximately” as used herein is inclusive of the stated value and means within an acceptable range of deviation for the particular value as determined by one of ordinary skill in the art, considering the measurement in question and the error associated with measurement of the particular quantity (i.e., the limitations of the measurement system). For example, “about” can mean within one or more standard deviations, or within ±30%, 20%, 10%, 5% of the stated value.

Unless otherwise defined, all terms (including technical and scientific terms) used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. It will be further understood that terms, such as those defined in commonly used dictionaries, should be interpreted as having a meaning that is consistent with their meaning in the context of the relevant art and the present disclosure, and will not be interpreted in an idealized or overly formal sense unless expressly so defined herein.

Exemplary embodiments are described herein with reference to cross section illustrations that are schematic illustrations of idealized embodiments. As such, variations from the shapes of the illustrations as a result, for example, of manufacturing techniques and/or tolerances, are to be expected. Thus, embodiments described herein should not be construed as limited to the particular shapes of regions as illustrated herein but are to include deviations in shapes that result, for example, from manufacturing. For example, a region illustrated or described as flat may, typically, have rough and/or nonlinear features. Moreover, sharp angles that are illustrated may be rounded. Thus, the regions illustrated in the figures are schematic in nature and their shapes are not intended to illustrate the precise shape of a region and are not intended to limit the scope of the present claims.

An organometallic compound according to an embodiment may be represented by Formulae 1 or 2 below:

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L₁in Formula 1 may be selected from a ligand represented by Formula 3A below, a ligand represented by Formula 3B below, a ligand represented by Formula 3C below, and a ligand represented by Formula 3D below:

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wherein * and *′ in Formulae 3A to 3D are binding sites to M₁in Formula 1.

M₁in Formula 1 may be selected from iridium (Ir), platinum (Pt), osmium (Os), titanium (Ti), zirconium (Zr), hafnium (Hf), europium (Eu), terbium (Tb), and thulium (Tm), and M₂in Formula 2 may be selected from iridium (Ir), osmium (Os), and europium (Eu).

According to an embodiment, M₁Formula 1 may be iridium (Ir) or platinum (Pt), and M₂in Formula 2 may be iridium (Ir).

In the formulae above, Y₁to Y₁₅are each independently carbon (C) or nitrogen (N);

CY₁in Formula 1 may be selected from a pyrrole, an imidazole, a pyrazole, a thiazole, an isothiazole, an oxazole, an isooxazole, a triazole, a pyrazine, a pyrimidine, a pyridazine, a quinoline, an isoquinoline, a benzoquinoline, a quinoxaline, a quinazoline, a benzoimidazole, a benzooxazole, an isobenzooxazole, a triazole, a tetrazole, an oxadiazole, and a triazine.

For example, CY₁in Formula 1 may be selected from a pyrrole, an imidazole, a pyrazole, a thiazole, an isothiazole, an oxazole, an isooxazole, a triazole, a benzoimidazole, a benzooxazole, an isobenzooxazole, a triazole, a tetrazole, and an oxadiazole.

According to an embodiment, CY₁in Formula 1 may be an imidazole or a pyrazole, but is not limited thereto.

In formulae above, CY₃and CY₅to CY₁₃may be each independently a C₂-C₆₀heterocyclic group including at least one N.

For example, CY₃and CY₅to CY₁₃in the formulae above may be each independently selected from a pyrrole, an imidazole, a pyrazole, a thiazole, an isothiazole, an oxazole, an isooxazole, a pyridine, a pyrazine, a pyrimidine, a pyridazine, a quinoline, an isoquinoline, a benzoquinoline, a quinoxaline, a quinazoline, a benzoimidazole, a benzooxazole, an isobenzooxazole, a triazole, a tetrazole, an oxadiazole, and a triazine.

According to an embodiment, CY₃and CY₅to CY₁₃in the formulae above may be each independently selected from an imidazole, a pyrazole, a triazole, a pyridine, a pyrazine, a pyrimidine, a pyridazine, a triazole, a tetrazole, and a triazine, but are not limited thereto.

CY₂and CY₄in the formulae above are each independently selected from a C₅-C₆₀carbocyclic group and a C₂-C₆₀heterocyclic group.

For example, CY₂and CY₄may be each independently selected from a benzene, a naphthalene, a fluorene, a spiro-fluorene, an indene, a pyrrole, a thiophene, a furan, an imidazole, a pyrazole, a thiazole, an isothiazole, an oxazole, an isooxazole, a pyridine, a pyrazine, a pyrimidine, a pyridazine, a quinoline, an isoquinoline, a benzoquinoline, a quinoxaline, a quinazoline, a carbazole, a benzoimidazole, a benzofuran, a benzothiophene, an isobenzothiophene, a benzooxazole, an isobenzooxazole, a triazole, a tetrazole, an oxadiazole, a triazine, a dibenzofuran, and a dibenzothiophene.

In some embodiments, CY₂and CY₄may be each independently a benzene or a pyridine, but are not limited thereto.

Z₁of CY₁and Z₂of CY₂in Formula 1 are linked to each other by a single bond or a first linking group to form a saturated or unsaturated ring, and the first linking group may be selected from linking groups represented by Formula 6:

*—(Z₃₁)_b1—*′ Formula 6

Z₃₁in Formula 6 may be selected from *—O—*′, *—S—*′, *—N(Q₄₁)—*′, *—C(Q₄₂)(Q₄₃)—*′, *—C(Q₄₄)—C(Q₄₅)—*′ and

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Q₄₁to Q₄₉may be each independently selected from

a hydrogen, a deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, an amino group, an amidino group, a hydrazine group, a hydrazone group, a carboxylic acid group or a salt thereof, a sulfonic acid group or a salt thereof, a phosphoric acid group or a salt thereof, a C₁-C₆₀alkyl group, a C₂-C₆₀alkenyl group, a C₂-C₆₀alkynyl group, and a C₁-C₆₀alkoxy group;

a C₁-C₆₀alkyl group, a C₂-C₆₀alkenyl group, a C₂-C₆₅alkynyl group, and a C₁-C₆₀alkoxy group, each substituted with at least one selected from a deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, an amino group, an amidino group, a hydrazine group, a hydrazone group, a carboxylic acid group or a salt thereof, a sulfonic acid group or a salt thereof, a phosphoric acid group or a salt thereof, a C₃-C₁₀cycloalkyl group, a C₂-C₁₀heterocycloalkyl group, a C₃-C₁₀cycloalkenyl group, a C₂-C₁₀heterocycloalkenyl group, a C₆-C₆₀aryl group, a C₆-C₆₀aryloxy group, a C₆-C₆₀arylthio group, a C₂-C₆₀heteroaryl group, a monovalent non-aromatic condensed polycyclic group, and a monovalent non-aromatic condensed hetero-polycyclic group;

a C₃-C₁₀cycloalkyl group, a C₂-C₁₀heterocycloalkyl group, a C₃-C₁₀cycloalkenyl group, a C₂-C₁₀heterocycloalkenyl group, a C₆-C₆₀aryl group, a C₆-C₆₀aryloxy group, a C₆-C₆₀arylthio group, a C₂-C₆₀heteroaryl group, a monovalent non-aromatic condensed polycyclic group, and a monovalent non-aromatic condensed hetero-polycyclic group, each substituted with at least one selected from a deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, an amino group, an amidino group, a hydrazine group, a hydrazone group, a carboxylic acid group or a salt thereof, a sulfonic acid group or a salt thereof, a phosphoric acid group or a salt thereof, a C₁-C₆₀alkyl group, a C₂-C₆₀alkenyl group, a C₂-C₆₀alkynyl group, a C₁-C₆₀alkoxy group, a C₃-C₁₀cycloalkyl group, a C₂-C₁₀heterocycloalkyl group, a C₃-C₁₀cycloalkenyl group, a C₂-C₁₀heterocycloalkenyl group, a C₆-C₆₀aryl group, a C₆-C₆₀aryloxy group, a C₆-C₆₀arylthio group, a C₂-C₆₀heteroaryl group, a monovalent non-aromatic condensed polycyclic group, and a monovalent non-aromatic condensed hetero-polycyclic group, and

b1 is selected from an integer of 1 to 10, and when b1 is 2 or greater, groups Z₃₁may be identical or different.

Q₄₁to Q₄₉may be understood by referring to the description provided herein in connection with Z₁.

In the formulae above,

Y₁is linked to N by a single bond or a double bond,

Y₂is linked to C by a single bond or a double bond,

Y₃is linked to N by a single bond or a double bond,

Y₄is linked to C by a single bond or a double bond,

Y₅is linked to C by a single bond or a double bond,

Y₆is linked to N by a single bond or a double bond,

Y₇is linked to N by a single bond or a double bond,

Y₈is linked to N by a single bond or a double bond,

Y₉is linked to N by a single bond or a double bond,

Y₁₀is linked to N by a single bond or a double bond,

Y₁₁is linked to N by a single bond or a double bond,

Y₁₂is linked to N by a single bond or a double bond,

Y₁₃is linked to N by a single bond or a double bond,

Y₁₄is linked to N by a single bond or a double bond, and

Y₁₅is linked to N by a single bond or a double bond.

Z₁to Z₁₆in the formulae above may be each independently selected from a hydrogen, a deuterium, —F (fluoro group), —Cl (chloro group), —Br (bromo group), —I (iodo group), a hydroxyl group, a cyano group, a nitro group, an amino group, an amidino group, a hydrazine group, a hydrazone group, a carboxylic acid group or a salt thereof, a sulfonic acid group or a salt thereof, a phosphoric acid group or a salt thereof, —SF₅, 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 C₂-C₁₀heterocycloalkyl group, a substituted or unsubstituted C₃-C₁₀cycloalkenyl group, a substituted or unsubstituted C₂-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 C₂-C₆₀heteroaryl group, a substituted or unsubstituted monovalent non-aromatic condensed polycyclic group, a substituted or unsubstituted monovalent non-aromatic condensed heteropolycyclic group, —N(Q₁)(Q₂), —Si(Q₃)(Q₄)(Q₅), and —B(Q₆)(Q₇).

For example, Z₁and Z₁₆may be each independently selected from

a hydrogen, a deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, an amino group, an amidino group, a hydrazine group, a hydrazone group, a carboxylic acid group or a salt thereof, a sulfonic acid group or a salt thereof, a phosphoric acid group or a salt thereof, —SF₅, a C₁-C₆₀alkyl group, a C₂-C₆₀alkenyl group, a C₂-C₆₀alkynyl group, and a C₁-C₆₀alkoxy group;

a phenyl group, a pentalenyl group, an indenyl group, a naphthyl group, an azulenyl group, a heptalenyl group, an indacenyl group, an acenaphthyl group, a fluorenyl group, a spiro-fluorenyl group, a benzofluorenyl group, a dibenzofluorenyl group, a phenalenyl group, a phenanthrenyl group, an anthracenyl group, a fluoranthenyl group, a triphenylenyl group, a pyrenyl group, a chrysenyl group, a naphthacenyl group, a picenyl group, a perylenyl group, a pentaphenyl group, a hexacenyl group, a pentacenyl group, a rubicenyl group, a coronenyl group, an ovalenyl group, a pyrrolyl group, a thiophenyl group, a furanyl group, an imidazolyl group, a pyrazolyl group, a thiazolyl group, an isothiazolyl group, an oxazolyl group, an isooxazolyl group, a pyridinyl group, a pyrazinyl group, a pyrimidinyl group, a pyridazinyl group, an isoindolyl group, an indolyl group, an indazolyl group, a furanyl group, a quinolinyl group, an isoquinolinyl group, a benzoquinolinyl group, a phthalazinyl group, a naphthyridinyl group, a quinoxalinyl group, a quinazolinyl group, a cinnolinyl group, a carbazolyl group, a phenanthridinyl group, an acridinyl group, a phenathrolinyl group, a phenazinyl group, a benzoimidazoyl group, a benzofuranyl group, a benzothiophenyl group, an isobenzothiazolyl group, a benzooxazolyl group, an isobenzooxazolyl group, a triazolyl group, a tetrazolyl group, an oxadiazolyl group, a triazinyl group, a dibenzofuranyl group, a dibenzothiophenyl group, a benzocarbazolyl group, a dibenzocarbazolyl group, an imidazopyridinyl group, and an imidazopyrimidinyl group, each substituted with at least one of a deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, an amino group, an amidino group, a hydrazine group, a hydrazone group, a carboxylic acid group or a salt thereof, a sulfonic acid group or a salt thereof, a phosphoric acid group or a salt thereof, a C₁-C₆₀alkyl group, a C₂-C₆₀alkenyl group, a C₂-C₆₀alkynyl group, a C₁-C₆₀alkoxy group, a C₁-C₆₀alkyl group substituted with at least one —F, a C₁-C₆₀alkoxy group substituted with at least one —F, a phenyl group, a pentalenyl group, an indenyl group, a naphthyl group, an azulenyl group, a heptalenyl group, an indacenyl group, an acenaphthyl group, a fluorenyl group, a spiro-fluorenyl group, a benzofluorenyl group, a dibenzofluorenyl group, a phenalenyl group, a phenanthrenyl group, an anthracenyl group, a fluoranthenyl group, a triphenylenyl group, a pyrenyl group, a chrysenyl group, a naphthacenyl group, a picenyl group, a perylenyl group, a pentaphenyl group, a hexacenyl group, a pentacenyl group, a rubicenyl group, a coronenyl group, an ovalenyl group, a pyrrolyl group, a thiophenyl group, a furanyl group, an imidazolyl group, a pyrazolyl group, a thiazolyl group, an isothiazolyl group, an oxazolyl group, an isooxazolyl group, a pyridinyl group, a pyrazinyl group, a pyrimidinyl group, a pyridazinyl group, an isoindolyl group, an indolyl group, an indazolyl group, a furanyl group, a quinolinyl group, an isoquinolinyl group, a benzoquinolinyl group, a phthalazinyl group, a naphthyridinyl group, a quinoxalinyl group, a quinazolinyl group, a cinnolinyl group, a carbazolyl group, a phenanthridinyl group, an acridinyl group, a phenanthrolinyl group, a phenazinyl group, a benzoimidazolyl group, a benzofuranyl group, a benzothiophenyl group, an isobenzothiazolyl group, a benzooxazolyl group, an isobenzooxazolyl group, a triazolyl group, a tetrazolyl group, an oxadiazolyl group, a triazinyl group, a dibenzofuranyl group, a dibenzothiophenyl group, a benzocarbazolyl group, a dibenzocarbazolyl group, an imidazopyridinyl group, an imidazopyrimidinyl group, —N(Q₃₁)(Q₃₂), —Si(Q₃₃)(Q₃₄)(Q₃₆), and —B(Q₃₆)(Q₃₇), and

—N(Q₁)(Q₂), —Si(Q₃)(Q₄)(Q₆), and —B(Q₆)(Q₇);

wherein Q₁to Q₇and Q₃₁to Q₃₇may be each independently a hydrogen, a C₁-C₂₀alkyl group, a C₁-C₂₀alkoxy group, a phenyl group, a naphthyl group, an anthracenyl group, a pyrenyl group, a phenanthrenyl group, a fluorenyl group, a chrysenyl group, a carbazolyl group, a benzocarbazolyl group, a dibenzocarbazolyl group, a dibenzofuranyl group, a dibenzothiophenyl group, a pyridinyl group, a pyrimidinyl group, a triazinyl group, a quinolinyl group, an isoquinolinyl group, a quinazolinyl group, and a quinoxalinyl group.

According to an embodiment, Z₁to Z₁₆may be each independently selected from

a C₁-C₂₀alkyl group and a C₁-C₂₀alkoxy group, each substituted with at least one selected from a deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, an amino group, an amidino group, a hydrazine group, a hydrazone group, a carboxylic acid group or a salt thereof, a sulfonic acid group or a salt thereof, a phosphoric acid group or a salt thereof, a phenyl group, a naphthyl group, a pyridinyl group, and a pyrimidinyl group;

a phenyl group, a naphthyl group, a fluorenyl group, a phenanthrenyl group, an anthracenyl group, a fluoranthenyl group, a triphenylenyl group, a pyrenyl group, a chrysenyl group, a pyrrolyl group, a thiophenyl group, a furanyl group, an imidazolyl group, a pyrazolyl group, a thiazolyl group, an isothiazolyl group, a oxazolyl group, an isooxazolyl group, a pyridinyl group, a pyrazinyl group, a pyrimidinyl group, a pyridazinyl group, an isoindolyl group, a indolyl group, a indazolyl group, a purinyl group, a quinolinyl group, an isoquinolinyl group, a benzoquinolinyl group, a quinoxalinyl group, a quinazolinyl group, a cinnolinyl group, a carbazolyl group, a phenanthrolinyl group, a benzoimidazolyl group, a benzofuranyl group, a benzothiophenyl group, an isobenzothiazolyl group, a benzooxazolyl group, an isobenzooxazolyl group, a triazolyl group, a tetrazolyl group, a oxadiazolyl group, a triazinyl group, a dibenzofuranyl group, a dibenzothiophenyl group, a benzocarbazolyl group, a dibenzocarbazolyl group, an imidazopyridinyl group, and an imidazopyrimidinyl group, each substituted with at least one selected from a deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, an amino group, an amidino group, a hydrazine group, a hydrazone group, a carboxylic acid group or a salt thereof, a sulfonic acid group or a salt thereof, a phosphoric acid group or and a salt thereof, a C₁-C₂₀alkyl group, a C₁-C₂₀alkoxy group, a C₁-C₂₀alkyl group substituted with at least one —F, a C₁-C₂₀alkoxy group substituted with at least one —F, a phenyl group, a naphthyl group, a fluorenyl group, a phenanthrenyl group, an anthracenyl group, a fluoranthenyl group, a triphenylenyl group, a pyrenyl group, a chrysenyl group, a pyrolyl group, a thiophenyl group, a furanyl group, an imidazolyl group, a pyrazolyl group, a thiazolyl group, an isothiazolyl group, a oxazolyl group, an isooxazolyl group, a pyridenyl group, a pyrazinyl group, a pyrimidinyl group, a pyridazinyl group, an isoindolyl group, a indolyl group, a indazolyl group, a purinyl group, a quinolinyl group, an isoquinolinyl group, a benzoquinolinyl group, a quinoxalinyl group, a quinazolinyl group, a cinnolinyl group, a carbazolyl group, a phenanthrolinyl group, a benzoimidazolyl group, a benzofuranyl group, a benzothiophenyl group, an isobenzothiazolyl group, a benzoxazolyl group, an isobenzooxazolyl group, a triazolyl group, a tetrazolyl group, a oxdiazolyl group, a triazinyl group, a dibenzofuranyl group, a dibenzothiophenyl group, a benzocarbazolyl group, a dibenzocarbazolyl group, an imidazopyridinyl group, and an imidazopyrimidinyl group, but they are not limited thereto.

According to some embodiments, Z₁to Z₁₆may be each independently selected from

a hydrogen, —F, a cyano group, a nitro group, —SF₅, a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, an isobutyl group, a sec-butyl group, a tert-butyl group, an n-pentyl group, an isopentyl group, a sec-pentyl group, a tert-pentyl group, an n-hexyl group, an isohexyl group, a sec-hexyl group, a tert-hexyl group, an n-heptyl group, an isoheptyl group, a sec-heptyl group, a tert-heptyl group, an n-octyl group, an isooctyl group, a sec-octyl group, a tert-octyl group, an n-nonyl group, an isononyl group, a sec-nonyl group, a tert-nonyl group, an n-decyl group, an isodecyl group, a sec-decyl group, a tert-decyl group, a methoxy group, an ethoxy group, a propoxy group, a butoxy group, a pentoxy group, a phenyl group, a naphthyl group, a pyridinyl group, a pyrimidinyl group, and a triazinyl group; and

a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, an isobutyl group, a sec-butyl group, a tert-butyl group, an n-pentyl group, an isopentyl group, a sec-pentyl group, a tert-pentyl group, an n-hexyl group, an isohexyl group, a sec-hexyl group, a tert-hexyl group, an n-heptyl group, an isoheptyl group, a sec-heptyl group, a tert-heptyl group, an n-octyl group, an isooctyl group, a sec-octyl group, a tert-octyl group, an n-nonyl group, an isononyl group, a sec-nonyl group, a tert-nonyl group, an n-decyl group, an isodecyl group, a sec-decyl group, a tert-decyl group, a methoxy group, an ethoxy group, a propoxy group, a butoxy group, a pentoxy group, a phenyl group, a naphthyl group, a pyridinyl group, a pyrimidinyl group, and a triazinyl group, each substituted with at least one selected from —F, a cyano group, a nitro group, and —CF₃, but they are not limited thereto.

a1 in Formula 1 indicates the number of groups Z₁, and may be selected from an integer of 1 to 5. For example, a1 may be selected from an integer of 1 to 3, but is not limited thereto. When a1 is 2 or greater, two or more groups Z₁may be identical or different. a2 to a13 each indicate the number of groups Z₂to Z₁₃, and may be understood by referring to the description stated above in connection with a1.

n1 in Formula 1 may be 1 or 2.

Z₉and Z₁₀in Formula 3A are not linked to each other to form a ring.

The organometallic compound represented by Formulae 1 or 2 is neutral. That is, the organometallic compound represented by Formulae 1 or 2 is not a salt in which a cation is combined with an anion.

According to an embodiment, the organometallic compound may be represented by one of Formulae 1-1 to 1-63 below:

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In Formulae 1-1 to 1-63 above, Z₁and Z₂are already described in detail above, and Z₂₁to Z₂₃may be understood by referring to the description stated in connection with Z₁, aa1 and aa2 may be each independently selected from an integer of 1 to 4, ab1 and ab2 may be each independently selected from an integer of 1 to 3, and ac1 and ac2 may be each independently 1 or 2.

For example, Z₁, Z₂, and Z₂₁to Z₂₃in Formulae 1-1 to 1-63 may be each independently selected from

a phenyl group, a naphthyl group, a fluorenyl group, a phenanthrenyl group, an anthracenyl group, a fluoranthenyl group, a triphenylenyl group, a pyrenyl group, a chrysenyl group, a pyrrolyl group, a thiophenyl group, a furanyl group, an imidazolyl group, a pyrazolyl group, a thiazolyl group, an isothiazolyl group, a oxazolyl group, an isooxazolyl group, a pyridyl group, a pyrazinyl group, a pyrimidinyl group, a pyridazinyl group, an isoindolyl group, a indolyl group, a indazolyl group, a purinyl group, a quinolinyl group, an isoquinolinyl group, a benzoquinolinyl group, a quinoxalinyl group, a quinazolinyl group, a cinnolinyl group, a carbazolyl group, a phenathrolinyl group, a benzoimidazolyl group, a benzofuranyl group, a benzothiophenyl group, an isobenzothiazolyl group, a benzooxazolyl group, an isobenzooxazolyl group, a triazolyl group, a tetrazolyl group, a oxadiazolyl group, a triazinyl group, a dibenzofuranyl group, a dibenzothiophenyl group, a benzocarbazolyl group, a dibenzocarbazolyl group, an imidazopyridinyl group, and an imidazopyrimidinyl group, each substituted with at least one selected from a deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, an amino group, an amidino group, a hydrazine group, a hydrazone group, a carboxylic acid group or a salt thereof, a sulfonic acid group or a salt thereof, a phosphoric acid group or and a salt thereof, a C₁-C₂₀alkyl group, a C₁-C₂₀alkoxy group, a C₁-C₂₀alkyl group substituted with at least one —F, a C₁-C₂₀alkoxy group substituted with at least one —F, a phenyl group, a naphthyl group, a fluorenyl group, a phenanthrenyl group, an anthracenyl group, a fluoranthenyl group, a triphenylenyl group, a pyrenyl group, a chrysenyl group, a pyrrolyl group, a thiophenyl group, a furanyl group, an imidazolyl group, a pyrazolyl group, a thiazolyl group, an isothiazolyl group, a oxazolyl group, an isooxazolyl group, a pyridinyl group, a pyrazinyl group, a pyrimidinyl group, a pyridazinyl group, an isoindolyl group, a indolyl group, a indazolyl group, a purinyl group, a quinolinyl group, an isoquinolinyl group, a benzoquinolinyl group, a quinoxalinyl group, a quinazolinyl group, a cinnolinyl group, a carbazolyl group, a phenanthrolinyl group, a benzoimidazolyl group, a benzofuranyl group, a benzothiophenyl group, an isobenzothiazolyl group, a benzooxazolyl group, an isobenzooxazolyl group, a triazolyl group, a tetrazolyl group, a oxadiazolyl group, a triazinyl group, a dibenzofuranyl group, a dibenzothiophenyl group, a benzocarbazolyl group, a dibenzocarbazolyl group, an imidazopyridinyl group, and an imidazopyrimidinyl group, but they are not limited thereto.

L₁and n1 in Formulae 1-1 to 1-63 are already described in detail above.

In some embodiments, the organometallic compound may be represented by Formulae 2-1 or 2-2:

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In Formulae 2-1 and 2-2, Z₃to Z₈are already described above, aa3 and aa5 may be each independently selected from an integer of 1 to 4, aa4 and aa7 may be each independently selected from an integer of 1 to 3, and aa6 and aa8 may be each independently selected from an integer of 1 or 2.

For example, R₃to R₈in Formulae 2-1 and 2-2 may be each independently selected from a hydrogen, a deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, an amino group, an amidino group, a hydrazine group, a hydrazone group, a carboxylic acid group or a salt thereof, a sulfonic acid group or a salt thereof, a phosphoric acid group or a salt thereof, —SF₅, a C₁-C₂₀alkyl group, and a C₁-C₂₀alkoxy group;

a phenyl group, a naphthyl group, a fluorenyl group, a phenanthrenyl group, an anthracenyl group, a fluoranthenyl group, a triphenylenyl group, a pyrenyl group, a chrysenyl group, a pyrrolyl group, a thiophenyl group, a furanyl group, an imidazolyl group, a pyrazolyl group, a thiazolyl group, an isothiazolyl group, a oxazolyl group, an isooxazolyl group, a pyridinyl group, a pyrazinyl group, a pyrimidinyl group, a pyridazinyl group, an isoindolyl group, a indolyl group, a indazolyl group, a purinyl group, a quinolinyl group, an isoquinolinyl group, a benzoquinolinyl group, a quinoxalinyl group, a quinazolinyl group, a cinnolinyl group, a carbazolyl group, a phenathrolinyl group, a benzoimidazolyl group, a benzofuranyl group, a benzothiophenyl group, an isobenzothiazolyl group, a benzooxazolyl group, an isobenzooxazolyl group, a triazolyl group, a tetrazolyl group, a oxadiazolyl group, a triazinyl group, dibenzofuranyl group, a dibenzothiophenyl group, a benzocarbazolyl group, a dibenzocarbazolyl group, an imidazopyridinyl group, and an imidazopyrimidinyl group, each substituted with at least one selected from a deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, an amino group, an amidino group, a hydrazine group, a hydrazone group, a carboxylic acid group or a salt thereof, a sulfonic acid group or a salt thereof, a phosphoric acid group or and a salt thereof, a C₁-C₂₀alkyl group, a C₁-C₂₀alkoxy group, a C₁-C₂₀alkyl group substituted with at least one —F, a C₁-C₂₀alkoxy group substituted with at least one —F, a phenyl group, a naphthyl group, a fluorenyl group, a phenanthrenyl group, an anthracenyl group, a fluoranthenyl group, a triphenylenyl group, a pyrenyl group, a chrysenyl group, a pyrrolyl group, a thiophenyl group, a furanyl group, an imidazolyl group, a pyrazolyl group, a thiazolyl group, an isothiazolyl group, a oxazolyl group, an isooxazolyl group, a pyridinyl group, a pyrazinyl group, a pyrimidinyl group, a pyridazinyl group, an isoindolyl group, a indolyl group, a indazolyl group, a purinyl group, a quinolinyl group, an isoquinolinyl group, a benzoquinolinyl group, a quinoxalinyl group, a quinazolinyl group, a cinnolinyl group, a carbazolyl group, a phenanthrolinyl group, a benzoimidazolyl group, a benzofuranyl group, a benzothiophenyl group, an isobenzothiazolyl group, a benzooxazolyl group, an isobenzooxazolyl group, a triazolyl group, a tetrazolyl group, a oxadiazolyl group, a triazinyl group, a dibenzofuranyl group, a dibenzothiophenyl group, a benzocarbazolyl group, a dibenzocarbazolyl group, an imidazopyridinyl group, and an imidazopyrimidinyl group, but they are not limited thereto.

According to some embodiments, L₁in Formula 1 may include a ligand represented by one of Formulae 3A-1 to 3A-20, 3B-1 to 3B-5, 3C-1 to 3C-5, and 3D-1 to 3D-5 below:

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In the formulae above, Z₉to Z₁₃are already described above, aa10, aa11, aa12, and aa13 may be each independently selected from an integer of 1 to 4, ab9, ab10, ab11, ab12, and ab13 may be each independently selected from an integer of 1 to 3, and ac9, ac10, ac11, ac12, and ac13 may be each independently 1 or 2.

For example, Z₉and Z₁₃in the formulae may be each independently selected from

a phenyl group, a naphthyl group, a fluorenyl group, a phenanthrenyl group, an anthracenyl group, a fluoranthenyl group, a triphenylenyl group, a pyrenyl group, a chrysenyl group, a pyrroyl group, a thiophenyl group, a furanyl group, an imidazolyl group, a pyrazolyl group, a thiazolyl group, an isothiazolyl group, an oxazolyl group, an isooxazolyl group, a pyridinyl group, a pyrazinyl group, a pyrimidinyl group, a pyridazinyl group, an isoindolyl group, an indolyl group, an indazolyl group, a purinyl group, a quinolinyl group, an isoquinolinyl group, a benzoquinolinyl group, a quinoxalinyl group, a quinazolinyl group, a cinnolinyl group, a carbazolyl group, a phenanthrolinyl group, a benzoimidazolyl group, a benzofuranyl group, a benzothiophenyl group, an isobenzothiazolyl group, a benzooxazolyl group, an isobenzooxazolyl group, a triazolyl group, a tetrazolyl group, an oxadiazolyl group, a triazinyl group, a dibenzofuranyl group, a dibenzothiophenyl group, a benzocarbazolyl group, a dibenzocarbazolyl group, an imidazopyridinyl group, and an imidazopyrimidinyl group; and a phenyl group, a naphthyl group, a fluorenyl group, a phenanthrenyl group, an anthracenyl group, a fluoranthenyl group, a triphenylenyl group, a pyrenyl group, a chrysenyl group, a pyrrolyl group, a thiophenyl group, a furanyl group, an imidazolyl group, a pyrazolyl group, a thiazolyl group, an isothiazolyl group, a oxazolyl group, an isooxazolyl group, a pyridinyl group, a pyrazinyl group, a pyrimidinyl group, a pyridazinyl group, an isoindolyl group, a indolyl group, a indazolyl group, a purinyl group, a quinolinyl group, an isoquinolinyl group, a benzoquinolinyl group, a quinoxalinyl group, a quinazolinyl group, a cinnolinyl group, a carbazolyl group, a phenanthrolinyl group, a benzoimidazolyl group, a benzofuranyl group, a benzothiophenyl group, an isobenzothiazolyl group, a benzooxazolyl group, an isobenzooxazolyl group, a triazolyl group, a tetrazolyl group, a oxadiazolyl group, a triazinyl group, a dibenzofuranyl group, a dibenzothiophenyl group, a benzocarbazolyl group, a dibenzocarbazolyl group, an imidazopyridinyl group, and an imidazopyrimidinyl group, each substituted with at least one selected from a deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, an amino group, an amidino group, a hydrazine group, a hydrazone group, a carboxylic acid group or a salt thereof, a sulfonic acid group or a salt thereof, a phosphoric acid group or and a salt thereof, a C₁-C₂₀alkyl group, a C₁-C₂₀alkoxy group, a C₁-C₂₀alkyl group substituted with at least one —F, a C₁-C₂₀alkoxy group substituted with at least one —F, a phenyl group, a naphthyl group, a fluorenyl group, a phenanthrenyl group, an anthracenyl group, a fluoranthenyl group, a triphenylenyl group, a pyrenyl group, a chrysenyl group, a pyrrolyl group, a thiophenyl group, a furanyl group, an imidazolyl group, a pyrazolyl group, a thiazolyl group, an isothiazolyl group, a oxazolyl group, an isooxazolyl group, a pyridinyl group, a pyrazinyl group, a pyrimidinyl group, a pyridazinyl group, an isoindolyl group, a indolyl group, a indazolyl group, a purinyl group, a quinolinyl group, an isoquinolinyl group, a benzoquinolinyl group, a quinoxalinyl group, a quinazolinyl group, a cinnolinyl group, a carbazolyl group, a phenanthrolinyl group, a benzoimidazolyl group, a benzofuranyl group, a benzothiophenyl group, an isobenzothiazolyl group, a benzooxazolyl group, an isobenzooxazolyl group, a triazolyl group, a tetrazolyl group, a oxadiazolyl group, a triazinyl group, a dibenzofuranyl group, a dibenzothiophenyl group, a benzocarbazolyl group, a dibenzocarbazolyl group, an imidazopyridinyl group, and an imidazopyrimidinyl group, but they are not limited thereto.

In some embodiments, the organometallic compound may be represented by one of Formulae 1-1 to 1-63, and L₁in Formulae 1-1 to 63 may be represented by one of Formula 3A-1 to 3A-20, 3B-1 to 3B-5, 3C-1 to 3C-5, and 3D-1 to 3D-5.

In some embodiments, the organometallic compound may be one of Compounds 1 to 13 below, but is not limited thereto:

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The highest occupied molecular orbital (HOMO) energy level, lowest unoccupied molecular orbital (LUMO) energy level, S1 energy level, T1 energy level, and maximum luminescent wavelength of Compounds 1 to 4 and 6 to 13 were evaluated by using program Gaussian 09. Geometry optimizations and vibration frequencies calculations were performed by using density functional theory (DFT) having the B3LYP functional and a 6-31G (d) basis set. The excited state of Compounds 1 to 13 in molecule was evaluated based on Time dependent DFT (TD-DFT) theory at B3LYP/6-31 G(d) level.

TABLE 1

Compound
HOMO
LUMO
S1 energy level
T1 energy level

No.
(eV)
(eV)
(eV)
(eV)

2
−5.501
−1.741
3.759
2.816

5
−5.830
−1.872
3.958
2.877

1
−5.382
−1.527
3.855
2.912

3
−5.704
−1.647
4.056
2.969

6
−5.273
−1.669
3.604
2.772

7
−5.613
−1.798
3.815
2.875

8
−5.164
−1.456
3.708
2.871

9
−5499
−1.607
3.892
2.907

10
−5.268
−1.624
3.644
2.817

11
−5.606
−1.752
3.855
2.897

12
−5.159
−1.417
3.742
2.911

13
−5496
−1.561
3.935
2.925

From Table 1, it was confirmed that Compounds 1 to 3 and 5 to 13 have electrical characteristics that are suitable for use as a material (for example, a dopant) for use in an organic light-emitting device.

The organometallic compound represented by Formulae 1 or 2 is neutral. That is, the organometallic compound represented by Formula 1 is not in the form of a salt consisting of the pair of a cation and an anion. Accordingly, a deposition method may be used to form a layer including the organometallic compound represented by Formula 1. In some embodiments, a layer including the organometallic compound represented by Formulae 1 or 2 may be formed by deposition at a temperature of about 100 to about 500° C., at a vacuum degree of about 10⁻⁸to about 10⁻³torr, and at a deposition speed of about 0.01 to about 100 Angstroms per second (A/sec). Accordingly, manufacturing workability of a device including the organometallic compound represented by Formulae 1 or 2 may improve.

Formula 1 includes one of Ligand 1 below having one carbon-metal bond, and Formula 2 includes one of Ligand 2 below having one carbon-metal bond. Accordingly, the organometallic compound represented by Formulae 1 or 2 contains one carbon-metal bond. Accordingly, the organometallic compound may have excellent thermal stability, and thus, an organic light-emitting device including the organometallic compound may have long lifespan characteristics.

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Methods of preparation of the organometallic compounds represented by Formulae 1 or 2 may be apparent to one of ordinary skill in the art by referring to Synthesis Examples that will be given below.

The organometallic compound represented by Formulae 1 or 2 is suitable for use in an organic layer of an organic light-emitting device, for example, for use as a dopant in an emission layer of the organic layer. Thus, another aspect provides an organic light-emitting device that includes:

a first electrode;

a second electrode; and

an organic layer that is disposed between the first electrode and the second electrode,

wherein the organic layer includes an emission layer and at least one organometallic compound represented by Formulae 1 or 2.

The organic light-emitting device may have, due to the inclusion of an organic layer including the organometallic compound represented by Formulae 1 or 2, low driving voltage, high efficiency, high brightness, and long lifespan. In an embodiment, an organic light-emitting device including the organometallic compound represented by Formulae 1 or 2 may emit deep blue light having a maximum luminescent wavelength of about 460 nanometers (nm) to about 500 nm, an x color coordinate of about 0.16 to about 0.22, and an y color coordinate of about 0.26 to about 0.36.

The organometallic compound represented by Formulae 1 or 2 may be used between a pair of electrodes of an organic light-emitting device. For example, the organometallic compound represented by Formulae 1 or 2 may be included in the emission layer. In this regard, the organometallic compound may act as a dopant, and the emission layer may further include a host, wherein an amount of the organometallic compound represented by Formulae 1 or 2 is smaller than an amount of the host.

The expression “(an organic layer) includes at least one organometallic compound” used herein may include a case in which “(an organic layer) includes the same organometallic compound selected from organometallic compounds represented by Formulae 1 or 2 and a case in which (an organic layer) includes two or more different organometallic compounds selected from organometallic compounds represented by Formulae 1 or 2.

For example, the organic layer may include, as the organometallic compound, only Compound 1. In this regard, Compound 1 may be situated in an emission layer of the organic light-emitting device. In some embodiments, the organic layer may include, as the organometallic compound, Compound 1 and Compound 2. In this regard, Compound 1 and Compound 2 may be situated in an identical layer (for example, Compound 1 and Compound 2 all may be situated in an emission layer).

The first electrode may be an anode, which is a hole injection electrode, and the second electrode may be a cathode, which is an electron injection electrode, or the first electrode may be a cathode, which is an electron injection electrode, or the second electrode may be an anode, which is a hole injection electrode.

For example, the first electrode is an anode, and the second electrode is a cathode, and the organic layer includes:

i) a hole transport region that is disposed between the first electrode and the emission layer, wherein the hole transport region includes at least one of a hole injection layer, a hole transport layer, and an electron blocking layer, and

ii) an electron transport region that is disposed between the emission layer and the second electrode, wherein the electron transport region includes at least one selected from a hole blocking layer, an electron transport layer, and an electron injection layer.

The term “organic layer” used herein refers to a single layer and/or a plurality of layers disposed between the first electrode and the second electrode of an organic light-emitting device. The “organic layer” may include, in addition to an organic compound, an organometallic complex including metal.

FIG. 1 is a schematic view of an organic light-emitting device 10 according to an embodiment. Hereinafter, the structure of an organic light-emitting device according to an embodiment and a method of manufacturing an organic light-emitting device according to an embodiment will be described in connection with FIG. 1. The organic light-emitting device 10 includes a first electrode 11, an organic layer 15, and a second electrode 19, which are sequentially stacked.

In FIG. 1, a substrate may be additionally disposed under the first electrode 11 or above the second electrode 19. For use as the substrate, any substrate that is used in general organic light-emitting devices may be used. The substrate may be a glass substrate or transparent plastic substrate, each with excellent mechanical strength, thermal stability, transparency, surface smoothness, ease of handling, and water-proofness.

The first electrode 11 may be formed by depositing or sputtering a material for forming the first electrode on the substrate. The first electrode 11 may be an anode. The material for the first electrode 11 may be selected from materials with a high work function to allow holes be easily injected. The first electrode 11 may be a reflective electrode or a transmissive electrode. The material for the first electrode 11 may be an indium tin oxide (ITO), indium zinc oxide (IZO), tin oxide (SnO₂), or zinc oxide (ZnO). In some embodiments, the material for the first electrode 11 may be metal, such as magnesium (Mg), aluminum (Al), aluminum-lithium (Al—Li), calcium (Ca), magnesium-indium (Mg—In), or magnesium-silver (Mg—Ag).

The first electrode 11 may have a single-layer structure or a multi-layer structure including two or more layers. For example, the first electrode 11 may have a three-layered structure of ITO/Ag/ITO, but the structure of the first electrode 110 is not limited thereto.

An organic layer 15 is disposed on the first electrode 11.

The organic layer 15 may include a hole transport region, an emission layer, and an electron transport region.

The hole transport region may be disposed between the first electrode 11 and the emission layer.

The hole transport region may include at least one of a hole injection layer, a hole transport layer, an electron blocking layer, and a buffer layer.

The hole transport region may include only either a hole injection layer or a hole transport layer. According to another embodiment, the hole transport region may have a structure of hole injection layer/hole transport layer or hole injection layer/hole transport layer/electron blocking layer, which are sequentially stacked in this stated order from the first electrode 11.

When the hole transport region includes a hole injection layer (HIL), the hole injection layer may be formed on the first electrode 11 by using any one of various methods, for example, vacuum deposition, spin coating, casting, or Langmuir-Blodgett (LB) deposition.

When a hole injection layer is formed by vacuum deposition, the deposition conditions may vary according to a material that is used to form the hole injection layer, and the structure and thermal characteristics of the hole injection layer. For example, the deposition conditions may include a deposition temperature of about 100 to about 500° C., a vacuum pressure of about 10⁻⁸to about 10⁻³torr, and a deposition rate of about 0.01 to about 100 Å/sec. However, the deposition conditions are not limited thereto.

When the hole injection layer is formed using spin coating, coating conditions may vary according to the material used to form the hole injection layer, and the structure and thermal properties of the hole injection layer. For example, a coating speed may be from about 2,000 revolutions per minute (rpm) to about 5,000 rpm, and a temperature at which a heat treatment is performed to remove a solvent after coating may be from about 80° C. to about 200° C. However, the coating conditions are not limited thereto.

Conditions for a hole transport layer and an electron blocking layer may be understood by referring to conditions for forming the hole injection layer.

The hole transport region may include at least one selected from m-MTDATA, TDATA, 2-TNATA, NPB, 13-NPB, TPD, Spiro-TPD, Spiro-NPB, methylated NPB, TAPC, HMTPD, 4,4′,4″-tris(N-carbazolyl)triphenylamine (TCTA), polyaniline/dodecylbenzenesulfonic acid (Pani/DBSA), poly(3,4-ethylenedioxythiophene)/poly(4-styrenesulfonate) (PEDOT/PSS), polyaniline/camphor sulfonic acid (Pani/CSA), (polyaniline)/poly(4-styrenesulfonate) (PANI/PSS), a compound represented by Formula 201 below, and a compound represented by Formula 202 below:

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Ar₁₀₁and Ar₁₀₂in Formula 201 may be each independently selected from

a phenylene group, a pentalenylene group, an indenylene group, a naphthylene group, an azulenylene group, a heptalenylene group, an acenaphthylene group, a fluorenylene group, a phenalenylene group, a phenanthrenylene group, an anthracenylene group, a fluoranthenylene group, a triphenylenylene group, a pyrenylene group, a chrysenylenylene group, a naphthacenylene group, a picenylene group, a perylenylene group, and a pentacenylene group, each substituted with at least one of a deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, an amino group, an amidino group, a hydrazine group, a hydrazone group, a carboxylic acid group or a salt thereof, a sulfonic acid group or a salt thereof, a phosphoric acid group or a salt thereof, a C₁-C₆₀alkyl group, a C₂-C₆₀alkenyl group, a C₂-C₆₀alkynyl group, a C₁-C₆₀alkoxy group, a C₃-C₁₀cycloalkyl group, a C₃-C₁₀cycloalkenyl group, a C₂-C₁₀heterocycloalkyl group, a C₂-C₁₀heterocycloalkenyl group, a C₆-C₆₀aryl group, a C₆-C₆₀aryloxy group, a C₆-C₆₀arylthio group, a C₂-C₆₀heteroaryl group, a monovalent non-aromatic condensed polycyclic group, and a monovalent non-aromatic condensed heteropolycyclic group.

xa and xb in Formula 201 may be each independently an integer of 0 to 5, or 0, 1 or 2. For example, xa may be 1 and xb may be 0, but xa and xb are not limited thereto.

R₁₀₁to R₁₀₈, R₁₁₁to R₁₁₉, and R₁₂₁to R₁₂₄in Formulae 201 and 202 may be each independently selected from

a hydrogen, a deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, an amino group, an amidino group, a hydrazine group, a hydrazone group, a carboxylic acid group or a salt thereof, a sulfonic acid group or a salt thereof, a phosphoric acid group or a salt thereof, a C₁-C₁₀alkyl group (for example, a methyl group, an ethyl group, a propyl group, a butyl group, a pentyl group, a hexyl group, and so on), and a C₁-C₁₀alkoxy group (for example, a methoxy group, an ethoxy group, a propoxy group, a butoxy group, a pentoxy group, and so on);

a C₁-C₁₀alkyl group and a C₁-C₁₀alkoxy group, each substituted with at least one selected from a deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, an amino group, an amidino group, a hydrazine group, a hydrazone group, a carboxylic acid group or a salt thereof, a sulfonic acid group or a salt thereof, and a phosphoric acid group or a salt thereof;

a phenyl group, a naphthyl group, an anthracenyl group, a fluorenyl group, and a pyrenyl group; and

a phenyl group, a naphthyl group, an anthracenyl group, a fluorenyl group, and a pyrenyl group, each substituted with at least one selected from deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, an amino group, an amidino group, a hydrazine group, a hydrazone group, a carboxylic acid group or a salt thereof, a sulfonic acid group or a salt thereof, a phosphoric acid group or a salt thereof, a C₁-C₁₀alkyl group and a C₁-C₁₀alkoxy group, but they are not limited thereto.

R₁₀₉in Formula 201 may be selected from

a phenyl group, a naphthyl group, an anthracenyl group, and a pyridinyl group;

a phenyl group, a naphthyl group, an anthracenyl group, and a pyridinyl group, each substituted with at least one selected from a deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, an amino group, an amidino group, a hydrazine group, a hydrazone group, a carboxylic acid group or a salt thereof, a sulfonic acid group or a salt thereof, a phosphoric acid group or a salt thereof, a C₁-C₂₀alkyl group, and a C₁-C₂₀alkoxy group.

According to an embodiment, the compound represented by Formula 201 may be represented by Formula 201A below, but is not limited thereto:

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R₁₀₁, R₁₁₁, R₁₁₂, and R₁₀₉in Formula 201A may be understood by referring to the description provided herein.

For example, the compound represented by Formula 201, and the compound represented by Formula 202 may include compounds HT1 to HT20 illustrated below, but are not limited thereto.

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A thickness of the hole transport region may be in a range of about 100 Angstroms (Å) to about 10,000 Å, for example, about 100 Å to about 1,000 Å. When the hole transport region includes both a hole injection layer and a hole transport layer, a thickness of the hole injection layer may be in a range of about 50 Å to about 10,000 Å, for example, about 100 Å to about 1,000 Å, and a thickness of the hole transport layer may be in a range of about 50 Å to about 2,000 Å, for example about 100 Å to about 1,500 Å. When the thicknesses of the hole transport region, the hole injection layer, and the hole transport layer are within these ranges, satisfactory hole transporting characteristics may be obtained without a substantial increase in driving voltage.

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

The charge-generation material may be, for example, a p-dopant. The p-dopant may be one of a quinone derivative, a metal oxide, and a cyano group-containing compound, but is not limited thereto. Non-limiting examples of the p-dopant are a quinone derivative, such as tetracyanoquinonedimethane (TCNQ) or 2,3,5,6-tetrafluoro-tetracyano-1,4-benzoquinonedimethane (F4-TCNQ); a metal oxide, such as a tungsten oxide or a molybdenium oxide; and a cyano group-containing compound, such as Compound HT-D1 below, but are not limited thereto.

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The hole transport region may include a buffer layer.

Also, the buffer layer may compensate for an optical resonance distance according to a wavelength of light emitted from the emission layer, and thus, efficiency of a formed organic light-emitting device may be improved.

Then, an emission layer (EML) may be formed on the hole transport region by vacuum deposition, spin coating, casting, LB deposition, or the like. When the emission layer is formed by vacuum deposition or spin coating, the deposition or coating conditions may be similar to those applied to form the hole injection layer although the deposition or coating conditions may vary according to the material that is used to form the emission layer.

The emission layer may include a host and a dopant, and the dopant may include the organometallic compound represented by Formulae 1 or 2.

The host may include at least one selected from TPBi, TBADN, ADN (also referred to as “DNA”), CBP, CDBP, and TCP:

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According to another embodiment, the host may further include a compound represented by Formula 301 below.

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Ar₁₁₁and Ar₁₁₂in Formula 301 may be each independently selected from

a phenylene group, a naphthylene group, a phenanthrenylene group, and a pyrenylene group; and

a phenylene group, a naphthylene group, a phenanthrenylene group, a fluorenylene group, and a pyrenylene group, each substituted with at least one selected from a phenyl group, a naphthyl group, and an anthracenyl group.

Ar₁₁₃to Ar₁₁₆in Formula 301 may be each independently selected from

a C₁-C₁₀alkyl group, a phenyl group, a naphthyl group, a phenanthrenyl group and a pyrenyl group; and

a phenyl group, a naphthyl group, a phenanthrenyl group, a fluorenyl group, and a pyrenyl group, each substituted with at least one selected from a phenyl group, a naphthyl group, and an anthracenyl group.

g, h, I, and j in Formula 301 may be each independently an integer of 0 to 4, for example, an integer of 0, 1, or 2.

Ar₁₁₃and Ar₁₁₆in Formula 301 may be each independently selected from

a C₁-C₁₀alkyl group substituted with at least one selected from a phenyl group, a naphthyl group, and an anthracenyl group;

a phenyl group, a naphthyl group, an anthracenyl group, a pyrenyl, a phenanthrenyl group, and a fluorenyl group;

a phenyl group, a naphthyl group, an anthracenyl group, a pyrenyl group, a phenanthrenyl group, and a fluorenyl group, each substituted with at least one selected from a deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, an amino group, an amidino group, a hydrazine group, a hydrazone group, a carboxylic acid group or a salt thereof, a sulfonic acid or a salt thereof, a phosphoric acid or a salt thereof, a C₁-C₆₀alkyl group, a C₂-C₆₀alkenyl group, a C₂-C₆₀alkynyl group, a C₁-C₆₀alkoxy group, a phenyl group, a naphthyl group, an anthracenyl group, a pyrenyl group, a phenanthrenyl group, and a fluorenyl group; and

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but they are not limited thereto.

According to another embodiment, the host may include a compound represented by Formula 302 below:

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Ar₁₂₂to Ar₁₂₅in Formula 302 are the same as described in detail in connection with Ar₁₁₃in Formula 301.

Ar₁₂₆and Ar₁₂₇in Formula 302 may each be independently a C₁-C₁₀alkyl group (for example, a methyl group, an ethyl group, or a propyl group).

k and l in Formula 302 may be each independently an integer of 0 to 4. For example, k and l may be 0, 1, or 2.

The compound represented by Formula 301 and the compound represented by Formula 302 may include Compounds H1 to H42 illustrated below, but are not limited thereto.

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When the organic light-emitting device is a full color organic light-emitting device, the emission layer may be patterned into a red emission layer, a green emission layer, and a blue emission layer. According to another embodiment, due to a stack structure including a red emission layer, a green emission layer, and/or a blue emission layer, the emission layer may emit white light.

When the emission layer includes a host and a dopant, an amount of the dopant may be in a range of about 0.01 to about 15 parts by weight based on 100 parts by weight of the host, but is not limited thereto.

A thickness of the emission layer may be in a range of about 100 Å to about 1,000 Å, for example, about 200 Å to about 600 Å. When the thickness of the emission layer is within this range, excellent light-emission characteristics may be obtained without a substantial increase in driving voltage.

Then, an electron transport region may be disposed on the emission layer.

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

For example, the electron transport region may have a structure of hole blocking layer/electron transport layer/electron injection layer or a structure of electron transport layer/electron injection layer, but the structure of the electron transport region is not limited thereto. The electron transport layer may have a single-layered structure or a multi-layer structure including two or more different materials.

Conditions for forming the hole blocking layer, the electron transport layer, and the electron injection layer which constitute the electron transport region may be understood by referring to the conditions for forming the hole injection layer.

When the electron transport layer includes a hole blocking layer, the hole blocking layer may include, for example, at least one of BCP and Bphen, but may also include other materials.

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A thickness of the hole blocking layer may be in a range of about 20 Å to about 1,000 Å, for example, about 30 Å to about 300 Å. When the thickness of the hole blocking layer is within these ranges, the hole blocking layer may have excellent hole blocking characteristics without a substantial increase in driving voltage.

The electron transport layer may further include at least one selected from BCP, Bphen, Alq₃, Balq, TAZ, and NTAZ.

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According to another embodiment, the electron transport layer may include at least one of ET1 and ET2, but are not limited thereto:

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A thickness of the electron transport layer may be in a range of about 100 Å to about 1,000 Å, for example, about 150 Å to about 500 Å. When the thickness of the electron transport layer is within the range described above, the electron transport layer may have satisfactory electron transport characteristics without a substantial increase in driving voltage.

Also, the electron transport layer may further include, in addition to the materials described above, a metal-containing material.

The metal-containing material may include a Li complex. The Li complex may include, for example, Compound ET-D1 (lithium quinolate, LiQ) or ET-D2.

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The electron transport region may include an electron injection layer (EIL) that allows electrons to be easily provided from a second electrode 19.

The electron injection layer may include at least one selected from LiF, NaCl, CsF, Li₂O, BaO, and LiQ.

A thickness of the electron injection layer may be in a range of about 1 Å to about 100 Å, for example, about 3 Å to about 90 Å. When the thickness of the electron injection layer is within the range described above, the electron injection layer may have satisfactory electron injection characteristics without a substantial increase in driving voltage.

The second electrode 19 is disposed on the organic layer 15. The second electrode 19 may be a cathode. A material for forming the second electrode 19 may be metal, an alloy, an electrically conductive compound, and a combination thereof, which have a relatively low work function. For example, lithium (Li), magnesium (Mg), aluminum (Al), aluminum-lithium (Al—Li), calcium (Ca), magnesium-indium (Mg—In), or magnesium-silver (Mg—Ag) may be formed as the material for forming the second electrode 19. To manufacture a top emission type light-emitting device, a transmissive electrode formed using ITO or IZO may be used as the second electrode 19.

Hereinbefore, the organic light-emitting device has been described with reference to FIG. 1, but is not limited thereto.

A C₁-C₆₀alkyl group used herein refers to a linear or branched aliphatic hydrocarbon monovalent group having 1 to 60 carbon atoms. Detailed examples thereof are a methyl group, an ethyl group, a propyl group, an isobutyl group, a sec-butyl group, a tert-butyl group, a pentyl group, an iso-amyl group, and a hexyl group. A C₁-C₆₀alkylene group used herein refers to a divalent group having the same structure as the C₁-C₆₀alkyl group.

A C₁-C₆₀alkoxy group used herein refers to a monovalent group represented by —OA₁₀₁(wherein A₁₀₁is the C₁-C₆₀alkyl group). Detailed examples thereof are a methoxy group, an ethoxy group, and an isopropyloxy group.

A C₂-C₆₀alkenyl group used herein refers to a hydrocarbon group formed by substituting at least one carbon double bond in the middle or at the terminal of the C₂-C₆₀alkyl group. Detailed examples thereof are an ethenyl group, a propenyl group, and a butenyl group. A C₂-C₆₀alkenylene group used herein refers to a divalent group having the same structure as the C₂-C₆₀alkenyl group.

A C₂-C₆₀alkynyl group used herein refers to a hydrocarbon group formed by substituting at least one carbon triple bond in the middle or at the terminal of the C₂-C₆₀alkyl group. Detailed examples thereof are an ethynyl group, and a propynyl group. A C₂-C₆₀alkynylene group used herein refers to a divalent group having the same structure as the C₂-C₆₀alkynyl group.

A C₃-C₁₀cycloalkyl group used herein refers to a monovalent hydrocarbon monocyclic group having 3 to 10 carbon atoms. Detailed examples thereof are a cyclopropyl group, a cyclobutyl group, a cyclopentyl group, a cyclohexyl group, and a cycloheptyl group. A C₃-C₁₀cycloalkylene group used herein refers to a divalent group having the same structure as the C₃-C₁₀cycloalkyl group.

A C₂-C₁₀heterocycloalkyl group used herein refers to a monovalent monocyclic group having at least one hetero atom selected from N, O, P, and S as a ring-forming atom and 2 to 10 carbon atoms. Detailed examples thereof are a tetrahydrofuranyl group, and a tetrahydrothiophenyl group. A C₂-C₁₀heterocycloalkylene group used herein refers to a divalent group having the same structure as the C₂-C₁₀heterocycloalkyl group.

A C₃-C₁₀cycloalkenyl group used herein refers to a monovalent monocyclic group that has 3 to 10 carbon atoms and at least one double bond in the ring thereof, which is not aromatic. Detailed examples thereof are a cyclopentenyl group, a cyclohexenyl group, and a cycloheptenyl group. A C₃-C₁₀cycloalkenylene group used herein refers to a divalent group having the same structure as the C₃-C₁₀cycloalkenyl group.

A C₂-C₁₀heterocycloalkenyl group used herein refers to a monovalent monocyclic group that has at least one hetero atom selected from N, O, P, and S as a ring-forming atom, 2 to 10 carbon atoms, and at least one double bond in its ring. Detailed examples of the C₂-C₁₀heterocycloalkenyl group are a 2,3-dihydrofuranyl group and a 2,3-dihydrothiophenyl group. A C₂-C₁₀heterocycloalkenylene group used herein refers to a divalent group having the same structure as the C₂-C₁₀heterocycloalkenyl group.

A C₆-C₆₀aryl group used herein refers to a monovalent group having a carbocyclic aromatic system having 6 to 60 carbon atoms, and a C₆-C₆₀arylene group used herein refers to a divalent group having a carbocyclic aromatic system having 6 to 60 carbon atoms. Detailed examples of the C₆-C₆₀aryl group are a phenyl group, a naphthyl group, an anthracenyl group, a phenanthrenyl group, a pyrenyl group, and a chrysenyl group. When the C₆-C₆₀aryl group and the C₆-C₆₀arylene group each include two or more rings, the rings may be fused to each other.

A C₂-C₆₀heteroaryl group used herein refers to a monovalent group having a carbocyclic aromatic system that has at least one hetero atom selected from N, O, P, and S as a ring-forming atom, and 2 to 60 carbon atoms. A C₂-C₆₀heteroarylene group used herein refers to a divalent group having a carbocyclic aromatic system that has at least one hetero atom selected from N, O, P, and S as a ring-forming atom, and 2 to 60 carbon atoms. Examples of the C₂-C₆₀heteroaryl group are a pyridinyl group, a pyrimidinyl group, a pyrazinyl group, a pyridazinyl group, a triazinyl group, a quinolinyl group, and an isoquinolinyl group. When the C₂-C₆₀heteroaryl group and the C₂-C₆₀heteroarylene group each include two or more rings, the rings may be fused to each other.

A C₆-C₆₀aryloxy group used herein indicates —OA₁₀₂(wherein A₁₀₂is the C₆-C₆₀aryl group), and a C₆-C₆₀arylthio group indicates —SA₁₀₃(wherein A₁₀₃is the C₆-C₆₀aryl group).

A monovalent non-aromatic condensed polycyclic group used herein refers to a monovalent group that has two or more rings condensed to each other, only carbon atoms (for example, the number of carbon atoms may be in a range of 8 to 60) as a ring forming atom, which is non-aromatic in the entire molecular structure. An example of the monovalent non-aromatic condensed polycyclic group is a fluorenyl group. A divalent non-aromatic condensed polycyclic group used herein refers to a divalent group having the same structure as the monovalent non-aromatic condensed polycyclic group.

A monovalent non-aromatic condensed heteropolycyclic group used herein refers to a monovalent group that has two or more rings condensed to each other, has a heteroatom selected from N, O P, and S, other than carbon atoms (for example, the number of carbon atoms may be in a range of 2 to 60), as a ring forming atom, which is non-aromatic in the entire molecular structure. An example of the monovalent non-aromatic condensed heteropolycyclic group is a carbazolyl group. A divalent non-aromatic condensed heteropolycyclic group used herein refers to a divalent group having the same structure as the monovalent non-aromatic condensed heteropolycyclic group.

At least one of substituents of the substituted C₁-C₆₀alkyl group, the substituted C₂-C₆₀alkenyl group, the substituted C₂-C₆₀alkynyl group, the substituted C₁-C₆₀alkoxy group, the substituted C₃-C₁₀cycloalkyl group, the substituted C₂-C₁₀heterocycloalkyl group, the substituted C₃-C₁₀cycloalkenyl group, the substituted C₂-C₁₀heterocycloalkenyl group, the substituted C₆-C₆₀aryl group, the substituted C₆-C₆₀aryloxy group, the substituted C₆-C₆₀arylthio group, the substituted C₂-C₆₀heteroaryl group, the substituted monovalent non-aromatic condensed polycyclic group, and the substituted monovalent non-aromatic condensed heteropolycyclic group may be selected from

—N(Q₃₁)(Q₃₂), —Si(Q₃₃)(Q₃₄)(Q₃₆), and —B(Q₃₆)(Q₃₇);

wherein Q₁to Q₇, Q₁₁to Q₁₇, Q₂₁to Q₂₇, and Q₃₁to Q₃₇may be each independently a hydrogen, a C₁-C₆₀alkyl group, a C₂-C₆₀alkenyl group, a C₂-C₆₀alkynyl group, a C₁-C₆₀alkoxy group, a C₃-C₁₀cycloalkyl group, a C₂-C₁₀heterocycloalkyl group, a C₃-C₁₀cycloalkenyl group, a C₂-C₁₀heterocycloalkenyl group, a C₆-C₆₀aryl group, a C₆-C₆₀aryloxy group, a C₆-C₆₀arylthio group, a C₆-C₆₀heteroaryl group, a monovalent non-aromatic condensed polycyclic group, or a monovalent non-aromatic condensed heteropolycyclic group.

According to an embodiment, at least one of substituents of the substituted C₁-C₆₀alkyl group, the substituted C₂-C₆₀alkenyl group, the substituted C₂-C₆₀alkynyl group, the substituted C₁-C₆₀alkoxy group, the substituted C₃-C₁₀cycloalkyl group, the substituted C₂-C₁₀heterocycloalkyl group, the substituted C₃-C₁₀cycloalkenyl group, the substituted C₂-C₁₀heterocycloalkenyl group, the substituted C₆-C₆₀aryl group, the substituted C₆-C₆₀aryloxy group, the substituted C₆-C₆₀arylthio group, the substituted C₂-C₆₀heteroaryl group, the substituted monovalent non-aromatic condensed polycyclic group, and the substituted monovalent non-aromatic condensed heteropolycyclic group may be selected from

a C₁-C₆₀alkyl group, a C₂-C₆₀alkenyl group, a C₂-C₆₀alkynyl group, and a C₁-C₆₀alkoxy group, each substituted with at least one selected from a deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, an amino group, an amidino group, a hydrazine group, a hydrazone group, a carboxylic acid group or a salt thereof, a sulfonic acid group or a salt thereof, a phosphoric acid group or a salt thereof, a cyclopentyl group, a cyclohexyl group, a cycloheptyl group, a cyclopentenyl group, a cycloheptenyl group, a phenyl group, a pentalenyl group, an indenyl group, a naphthyl group, an azulenyl group, a heptalenyl group, an indacenyl group, an acenaphthyl group, a fluorenyl group, a spiro-fluorenyl group, a benzofluorenyl group, a dibenzofluorenyl group, a phenalenyl group, a phenanthrenyl group, an anthracenyl group, a fluoranthenyl group, a triphenylenyl group, a pyrenyl group, a chrysenyl group, a naphthacenyl group, a picenyl group, a perylenyl group, a pentaphenyl group, a hexacenyl group, a pentacenyl group, a rubicenyl group, a coronenyl group, an ovalenyl group, a pyrrolyl group, a thiophenyl group, a furanyl group, an imidazolyl group, a pyrazolyl group, a thiazolyl group, an isothiazolyl group, an oxazolyl group, an isoxazolyl group, a pyridinyl group, a pyrazinyl group, a pyrimidinyl group, a pyridazinyl group, an isoindolyl group, an indolyl group, an indazolyl group, a purinyl group, a quinolinyl group, an isoquinolinyl group, a benzoquinolinyl group, a phthalazinyl group, a naphthyridinyl group, a quinoxalinyl group, a quinazolinyl group, a cynolinyl group, a carbazolyl group, a phenanthridinyl group, an acridinyl group, a phenanthrolinyl group, a phenazinyl group, a benzoimidazolyl group, a benzofuranyl group, a benzothiophenyl group, an isobenzothiazolyl group, a benzooxazolyl group, an isobenzooxazolyl group, a triazolyl group, a tetrazolyl group, an oxadiazolyl group, a triazinyl group, a dibenzofuranyl group, a dibenzothiophenyl group, a benzocarbazolyl group, a dibenzocarbazolyl group, an imidazopyridinyl group, an imidazopyrimidinyl group, N(Q₁₁)(Q₁₂), —Si(Q₁₃)(Q₁₄)(Q₁₅), and —B(Q₁₆)(Q₁₇);

a cyclopentyl group, a cyclohexyl group, a cycloheptyl group, a cyclopentenyl group, a cycloheptenyl group, a phenyl group, a pentalenyl group, an indenyl group, a naphthyl group, an azulenyl group, a heptalenyl group, an indacenyl group, an acenaphthyl group, a fluorenyl group, a spiro-fluorenyl group, a benzofluorenyl group, a dibenzofluorenyl group, a phenalenyl group, a phenanthrenyl group, an anthracenyl group, a fluoranthenyl group, a triphenylenyl group, a pyrenyl group, a chrysenyl group, a naphthacenyl group, a picenyl group, a perylenyl group, a pentaphenyl group, a hexacenyl group, a pentacenyl group, a rubicenyl group, a coronenyl group, an ovalenyl group, a pyrrolyl group, a thiophenyl group, a furanyl group, an imidazolyl group, a pyrazolyl group, a thiazolyl group, an isothiazolyl group, an oxazolyl group, an isoxazolyl group, a pyridinyl group, a pyrazinyl group, a pyrimidinyl group, a pyridazinyl group, an isoindolyl group, an indolyl group, an indazolyl group, a purinyl group, a quinolinyl group, an isoquinolinyl group, a benzoquinolinyl group, a phthalazinyl group, a naphthyridinyl group, a quinoxalinyl group, a quinazolinyl group, a cynolinyl group, a carbazolyl group, a phenanthridinyl group, an acridinyl group, a phenanthrolinyl group, a phenazinyl group, a benzoimidazolyl group, a benzofuranyl group, a benzothiophenyl group, an isobenzothiazolyl group, a benzooxazolyl group, an isobenzooxazolyl group, a triazolyl group, a tetrazolyl group, an oxadiazolyl group, a triazinyl group, a dibenzofuranyl group, a dibenzothiophenyl group, a benzocarbazolyl group, a dibenzocarbazolyl group, an imidazopyridinyl group, and an imidazopyrimidinyl group;

- a cyclopentyl group, a cyclohexyl group, a cycloheptyl group, a cyclopentenyl group, a cycloheptenyl group, a phenyl group, a pentalenyl group, an indenyl group, a naphthyl group, an azulenyl group, a heptalenyl group, an indacenyl group, an acenaphthyl group, a fluorenyl group, a spiro-fluorenyl group, a benzofluorenyl group, a dibenzofluorenyl group, a phenalenyl group, a phenanthrenyl group, an anthracenyl group, a fluoranthenyl group, a triphenylenyl group, a pyrenyl group, a chrysenyl group, a naphthacenyl group, a picenyl group, a perylenyl group, a pentaphenyl group, a hexacenyl group, a pentacenyl group, a rubicenyl group, a coronenyl group, an ovalenyl group, a pyrrolyl group, a thiophenyl group, a furanyl group, an imidazolyl group, a pyrazolyl group, a thiazolyl group, an isothiazolyl group, an oxazolyl group, an isoxazolyl group, a pyridinyl group, a pyrazinyl group, a pyrimidinyl group, a pyridazinyl group, an isoindolyl group, an indolyl group, an indazolyl group, a purinyl group, a quinolinyl group, an isoquinolinyl group, a benzoquinolinyl group, a phthalazinyl group, a naphthyridinyl group, a quinoxalinyl group, a quinazolinyl group, a cynolinyl group, a carbazolyl group, a phenanthridinyl group, an acridinyl group, a phenanthrolinyl group, a phenazinyl group, a benzoimidazolyl group, a benzofuranyl group, a benzothiophenyl group, an isobenzothiazolyl group, a benzooxazolyl group, an isobenzooxazolyl group, a triazolyl group, a tetrazolyl group, an oxadiazolyl group, a triazinyl group, a dibenzofuranyl group, a dibenzothiophenyl group, a benzocarbazolyl group, a dibenzocarbazolyl group, an imidazopyridinyl group, and an imidazopyrimidinyl group, each substituted with at least one selected from a deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, an amino group, an amidino group, a hydrazine group, a hydrazone group, a carboxylic acid group or a salt thereof, a sulfonic acid group or a salt thereof, a phosphoric acid group or a salt thereof, a C₁-C₆₀alkyl group, a C₂-C₆₀alkenyl group, a C₂-C₆₀alkynyl group, a C₁-C₆₀alkoxy group, a phenyl group, a naphthyl group, —N(Q₂₁)(Q₂₂), —Si(Q₂₃)(Q₂₄)(Q₂₆), and —B(Q₂₆)(Q₂₇); and

—N(Q₃₁)(Q₃₂), —Si(Q₃₃)(Q₃₄)(Q₃₅), and —B(Q₃₆)(Q₃₇);

Q₁₁to Q₁₇, Q₂₁to Q₂₇, and Q₃₁to Q₃₇may be each independently selected from a hydrogen, a C₁-C₆₀alkyl group, a C₂-C₆₀alkenyl group, a C₂-C₆₀alkynyl group, a C₁-C₆₀alkoxy group, a cyclopentyl group, a cyclohexyl group, a cycloheptyl group, a cyclopentenyl group, a cycloheptenyl group, a phenyl group, a pentalenyl group, an indenyl group, a naphthyl group, an azulenyl group, a heptalenyl group, an indacenyl group, an acenaphthyl group, a fluorenyl group, a spiro-fluorenyl group, a benzofluorenyl group, a dibenzofluorenyl group, a phenalenyl group, a phenanthrenyl group, an anthracenyl group, a fluoranthenyl group, a triphenylenyl group, a pyrenyl group, a chrysenyl group, a naphthacenyl group, a picenyl group, a perylenyl group, a pentaphenyl group, a hexacenyl group, a pentacenyl group, a rubicenyl group, a coronenyl group, an ovalenyl group, a pyrrolyl group, a thiophenyl group, a furanyl group, an imidazolyl group, a pyrazolyl group, a thiazolyl group, an isothiazolyl group, an oxazolyl group, an isoxazolyl group, a pyridinyl group, a pyrazinyl group, a pyrimidinyl group, a pyridazinyl group, an isoindolyl group, an indolyl group, an indazolyl group, a purinyl group, a quinolinyl group, an isoquinolinyl group, a benzoquinolinyl group, a phthalazinyl group, a naphthyridinyl group, a quinoxalinyl group, a quinazolinyl group, a cynolinyl group, a carbazolyl group, a phenanthridinyl group, an acridinyl group, a phenanthrolinyl group, a phenazinyl group, a benzoimidazolyl group, a benzofuranyl group, a benzothiophenyl group, an isobenzothiazolyl group, a benzooxazolyl group, an isobenzooxazolyl group, a triazolyl group, a tetrazolyl group, an oxadiazolyl group, a triazinyl group, a dibenzofuranyl group, a dibenzothiophenyl group, a benzocarbazolyl group, a dibenzocarbazolyl group, an imidazopyridinyl group, and an imidazopyrimidinyl group.

Hereinafter, a compound and an organic light-emitting device according to embodiments are described in detail with reference to Synthesis Example and Examples. However, the organic light-emitting device is not limited thereto. The wording “B was used instead of A” used in describing Synthesis Examples means that a molar equivalent of A was identical to a molar equivalent of B.

EXAMPLE
Synthesis Example 1
Synthesis of Compound 1

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4 mmol of Ligand 1 [1-N-methyl-3-trifluoromethyl-2-phenyl-imidazole] (0.904 g) was reacted with 3.86 mmol of IrCl₃.3H₂O (1.36 g) in methoxy ethanol (85 mL), in a 2-neck flask in a nitrogen atmosphere, were reacted at a temperature of 140° C. for 4 hours. After the reaction product was cooled to room-temperature, 8.32 mmol of Ligand 2 [1-N—H-3-trifluoromethyl-2-(4′-tertiarybutyl-2′-pyridyl)-pyrazole] (2.238 g) and 17.08 mmol of a sodium carbonate (1.80 g) were added thereto, and the reaction product was stirred at a temperature of 140° C. overnight. The reaction product was cooled, and water was added thereto until a yellow green precipitate was formed. The formed precipitate was filtered and dried overnight in a vacuum oven at a temperature of 60° C., and the obtained product was purified by silica gel chromatography (methylene chloride and hexane were used as an eluent), thereby obtaining Compound 1 (yield: 45%).

FIG. 2 shows a mass (MS) spectrum of Compound 1 (measured by using matrix-assisted laser desorption/ionization time-of-flight mass spectroscopy (MALDI-TOF)).

Synthesis Example 2
Synthesis of Compound 2

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Compound 2 (yield: 40%) was obtained in the same manner as in Synthesis Example 1, except that 8.32 mmol of Ligand 3 [1-N—H-3-trifluoromethyl-2-(2′-pyridyl)-pyrazole] (1.77 g) was used instead of Ligand 2.

FIG. 3 shows a MS spectrum of Compound 2 (measured by using MALDI-TOF).

Synthesis Example 3
Synthesis of Compound 4

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Compound 4 (yield: 37%) was obtained in the same manner as in Synthesis Example 1, except that 4 mmol of Ligand 4 [1-N-methyl-3-trifluoromethyl-2-phenyl-imidazole] (0.676 g) was used instead of Ligand 1.

In a MS spectrum of Compound 4 (measured by using MALDI-TOF), a peak was observed at 941 m/z.

Evaluation Example 1
Evaluation of Highest Occupied Molecular Orbital (HOMO) Energy Level, Lowest Unoccupied Molecular Orbital (LUMO) Energy Level, and T1 Energy Level

A solution of Compound 1 (10⁻³M solution) in acetonitrile containing 0.1 mol of electrolyte (tetrabutylammonium hexafluorophosphate) was prepared to evaluate a cyclic voltammogram of Compound 1. Here, 0.1 mm diameter of a platinum disk electrode was used as a working electrode, a platinum wire was used as a reference electrode and counter electrode, and ferrocene was used as an internal standard.

FIGS. 4A and 4B show cyclic voltammograms of Compound 1.

HOMO energy level of Compound 1 was calculated from a first oxidation potential of FIG. 4A with respect to Fc/Fc⁺Versus NHE (−4.80 V) (NHE is a normal hydrogen electrode), and a LUMO energy level of Compound 1 was calculated from a first reduction potential of FIG. 4B with respect to Fc/Fe⁺ Versus NHE (−4.80 V).

In some embodiments, an oxidation potential with respect to Fc/Fc⁺ Versus NHE (−4.80 V) (NHE is a normal hydrogen electrode) was calculated from the first oxidation peak of 0.84 V and a ferrocene oxidation peak of 0.23 V as shown in FIG. 4A, and the calculated value was −5.41 electron volt (eV). Accordingly, it was confirmed that a HOMO energy level of Compound 1 was −5.41 eV.

A reduction potential with respect to Fc/Fc⁺Versus NHE was calculated from the reduction peak of −2.72 V and a ferrocene reduction peak of −0.18 V as shown in FIG. 4B, and the calculation value was −1.90 eV. Accordingly, it was confirmed that a LUMO energy level of Compound 1 was −1.90 eV.

A T1 energy level of Compound 1 was evaluated from a higher energy peak (shoulder) of a photoluminescence (PL) spectrum of Compound 1, which will be described later in the specification.

A HOMO energy level, a LUMO energy level, and a T1 energy level of Compounds 2 and 4 were evaluated in the same manner as described above, and results thereof are shown in Table 2.

According to Table 2, Compounds 1, 2 and 4 were confirmed as having a HOMO energy level, a LUMO energy level, and a T1 energy level that are appropriate to be used as materials for an organic light-emitting device.

Evaluation Example 2
Evaluation of Thermal Decomposition

A thermal analysis (in N2 atmosphere, temperature range: room temperature to 800° C. (10° C./min)—TGA, from room temperature to 400° C.—DSC, Pan Type: Pt Pan in disposable Al Pan(TGA), disposable Al pan(DSC)) was performed with respect to Compound 1 by using thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC), and the result is shown in FIG. 5. According to FIG. 5, it was confirmed that decomposition temperature (T95%) of Compound 1 was 366° C. Thermal analysis was performed on Compounds 2 and 4 in the same manner as described above, and the results are shown in Table 2.

According to Table 2, Compounds 1, 2 and 4 were confirmed as having appropriate thermal stability to be used as materials for an organic light-emitting device.

TABLE 2

Compound 1
Compound 2
Compound 4

HOMO energy level (eV)
−5.41
−5.38
−5.7

LUMO energy level (eV)
−1.90
−1.86
−1.3

T1 energy level (nm)
467
468
452

T95% (° C.)
366
360
355

Evaluation Example 3
Evaluation of PL Spectrum

Compound 1 was diluted in toluene to a concentrate of 10 millimolar (mM), and then PL spectrum of Compound 1 in solution was measured by using an ISC PC1 spectrofluorometer that is equipped with a xenon lamp. Measuring PL spectrum was performed on Compounds 2 and 4 in solution in the same manner as described above, and the results are shown in FIG. 6 and Table 3.

TABLE 3

Compound 1
Compound 2
Compound 4

Maximum emission
493
497
482

peak (nm)

Shoulder (nm)
467
468
452

According to FIG. 6 and Table 3, Compounds 1, 2 and 4 were confirmed as having excellent light emission characteristics.

The organometallic compound according to embodiments has excellent electric characteristics and thermal stability. Accordingly, an organic light-emitting device including the organometallic compound may have a low driving voltage, high efficiency, high brightness, and a long lifespan.

It should be understood that the exemplary embodiments described therein should be considered in a descriptive sense only and not for purposes of limitation. Descriptions of features or aspects within each embodiment should typically be considered as available for other similar features or aspects in other embodiments.

While one or more embodiments have been described with reference to the figures, it will be understood by those of ordinary skill in the art that various changes in form and details may be made therein without departing from the spirit and scope of the present disclosure as defined by the following claims.

ORGANOMETALLIC COMPOUND AND ORGANIC LIGHT-EMITTING DEVICE INCLUDING THE SAME

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