Organic electroluminescent device and organic metal complex for organic electroluminescent device

Abstract

An organic electroluminescent device is provided. The organic electroluminescent device according to the embodiment includes a first electrode, a second electrode facing the first electrode, and a plurality of organic layers between the first electrode and the second electrode, wherein at least one of the plurality of organic layers comprises an organic metal complex, the organic metal complex comprising a metal atom as a central atom, a plurality of ligands connected to the metal atom, and a nitrogen atom connecting two of the plurality of ligands. The nitrogen atom comprises an aromatic ring group as a substituent. The aromatic ring group does not combine with any of the plurality of ligands to form a ring, thereby allowing the organic electroluminescent device to exhibit a low driving voltage and an improved lifespan.

Description

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS

[0002] This application claims priority to and the benefit of Korean Patent Application No. 10-2019-0094565, filed on August 2, 2019, which is hereby incorporated by reference in its entirety. Technical Field

[0003] The present disclosure herein relates to organic electroluminescent devices and organometallic complexes for organic electroluminescent devices. Background Art

[0004] Recently, organic electroluminescent displays as image display devices have been actively developed. The organic electroluminescent display is a so-called self-luminous display that generates excitons by recombining holes and electrons injected from a first electrode and a second electrode in a light-emitting layer, and realizes display by causing the generated excitons to fall (e.g., transition) to a ground state to emit light.

[0005] In order to apply organic electroluminescent devices to display devices, the development of organic metal complexes is being carried out to be used as dopant materials in the development of materials for light-emitting layers. Specifically, the development of organic metal complexes having improved or optimized light wavelengths and longer lifespans and organic metal complexes for organic electroluminescent devices is desired. Summary of the invention

[0006] The present disclosure provides organic electroluminescent devices with improved lifespan.

[0007] The present disclosure also provides organometallic complexes with improved lifetimes.

[0008] The embodiment of the present disclosure provides an organic electroluminescent device, comprising: a first electrode; a second electrode facing the first electrode; and a plurality of organic layers between the first electrode and the second electrode. At least one of the plurality of organic layers comprises an organic metal complex, the organic metal complex comprising a metal atom as a central atom; a plurality of ligands connected to the metal atom; and a nitrogen atom connecting two of the plurality of ligands. The nitrogen comprises an aromatic ring group as a substituent; and the aromatic ring group does not combine with any of the plurality of ligands to form a ring.

[0009] In an embodiment, the aromatic ring group may be a substituted or unsubstituted C6-30 aryl group, or a substituted or unsubstituted C2-30 heteroaryl group.

[0010] In embodiments, the metal atom may be Pt, Pd, Cu, Ag, Au, Rh, Ir, Ru, or Os.

[0011] In an embodiment, one of the plurality of ligands may be a substituted or unsubstituted 5-membered heterocyclic group, or a substituted or unsubstituted cyclic C2-30 heteroaryl group.

[0012] In an embodiment, the plurality of organic layers may include a hole transport region, a light emitting layer, and an electron transport region, and the organic metal complex may be included in the light emitting layer.

[0013] In an embodiment, the organic metal complex may be represented by Formula 1 below.

[0014] Formula 1

[0015]

[0016] In the above Formula 1, M may be Pt, Pd, Cu, Ag, Au, Rh, Ir, Ru or Os. 1 It may be a substituted or unsubstituted 5-membered heterocyclic group or a substituted or unsubstituted cyclic C2-30 heteroaryl group. 2 , L 3 and L 4 R and R are each independently a substituted or unsubstituted cyclic C6-30 aryl group or a substituted or unsubstituted cyclic C2-30 heteroaryl group. 1 , R 2 , R 3 and R 4 may each independently be a hydrogen atom, a deuterium atom, a halogen atom, a substituted or unsubstituted cyclic C6-30 aryl group, a substituted or unsubstituted cyclic C6-30 heteroaryl group, a substituted or unsubstituted C1-30 alkyl group, a substituted or unsubstituted C2-30 alkenyl group, a substituted or unsubstituted C2-30 alkynyl group, a substituted or unsubstituted amino group, a carbonyl group, a hydroxyl group, a thiol group, a nitrile group, a cyano group, a C1-30 alkoxy group, an ester group, a sulfonic acid group, a carboxyl group or a silyl group, and R 1 , R 2 , R 3 or R 4 At least some of the groups may be bonded to adjacent groups to form a ring.

[0017] R 5It may be a hydrogen atom, a deuterium atom, a halogen atom, a substituted or unsubstituted cyclic C6-30 aryl group, a substituted or unsubstituted cyclic C6-30 heteroaryl group, a substituted or unsubstituted C1-30 alkyl group, a substituted or unsubstituted C2-30 alkenyl group, a substituted or unsubstituted C2-30 alkynyl group, a substituted or unsubstituted amino group, a carbonyl group, a hydroxyl group, a thiol group, a nitrile group, a cyano group, a C1-30 alkoxy group, an ester group, a sulfonic acid group, a carboxyl group or a silyl group, and in the case of a plurality of R 5 In the case of multiple R 5 Can combine with each other to form a ring. 1 to n 4 may each independently be an integer from 0 to 3. 5 It can be an integer from 0 to 5. 1 , Y 2 , Y 3 , Y 4 and Y 5 can each independently be C, N, O or S.

[0018] A 1 Can be *-O-*, *-S-*, *-S(=O)-*, *-SO 2 -*、*-Se-*、*-NR 11 -*、*-R 11 P=O-*、*-CR 12 R 13 -*,*-C(=O)-*,*-SiR 12 R 13 -*、*-GeR 12 R 13 -*, *-BH-*, *-P(O)H-*, *-PH-*, *-NH-*, *-CR 12 H-*、*-CH 2 -*、*-SiH 2 -*、*-SiHR 12 -*、*-BR 14 -*or*-PR 14 -*.R 11 , R 12 , R 13 and R 14They may each independently be a hydrogen atom, a deuterium atom, a halogen atom, a substituted or unsubstituted cyclic C6-30 aryl group, a substituted or unsubstituted cyclic C6-30 heteroaryl group, a substituted or unsubstituted C1-30 alkyl group, a substituted or unsubstituted C2-30 alkenyl group, a substituted or unsubstituted C2-30 alkynyl group, a substituted or unsubstituted amino group, a carbonyl group, a hydroxyl group, a thiol group, a nitrile group, a cyano group, a C1-30 alkoxy group, an ester group, a sulfonic acid group, a carboxyl group or a silyl group, and may bond to an adjacent group to form a ring.

[0019] In an embodiment, the organic metal complex represented by the above Formula 1 may be represented by the following Formula 1-1.

[0020] Formula 1-1

[0021]

[0022] In the above formula 1-1, L 1 To L 4 , R 1 To R 5 、n 1 to n 5 , A 1 , R 11 To R 14 and Y 1 To Y 5 may be the same as defined by Formula 1 above.

[0023] In an embodiment, the organic metal complex represented by the above Formula 1 may be represented by the following Formula 1-2.

[0024] Formula 1-2

[0025]

[0026] In the above formula 1-2, M, L 1 , R 1 To R 5 、n 1 to n 5 , A 1 and R 11 To R 14 may be the same as defined by Formula 1 above.

[0027] In an embodiment, the organic metal complex represented by the above Formula 1 may be represented by the following Formulas 1-3.

[0028] Formula 1-3

[0029]

[0030] In the above formula 1-3, L 1 , R 1 To R 5 、n 1 to n 5 , A 1 and R 11 To R 14 may be the same as defined by Formula 1 above. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] The accompanying drawings are included to provide a further understanding of the present disclosure and are incorporated in and constitute a part of this specification. The accompanying drawings illustrate exemplary embodiments of the present disclosure and together with the description serve to explain the principles of the present disclosure. In the drawings:

[0032] Figure 1 is a cross-sectional view schematically showing an organic electroluminescent device according to an embodiment of the present disclosure;

[0033] Figure 2 is a cross-sectional view schematically showing an organic electroluminescent device according to an embodiment of the present disclosure;

[0034] Figure 3 is a cross-sectional view schematically showing an organic electroluminescent device according to an embodiment of the present disclosure; and

[0035] Figure 4 is a cross-sectional view schematically showing an organic electroluminescent device according to an embodiment of the present disclosure. DETAILED DESCRIPTION

[0036] The subject matter of the present disclosure may have various modifications and may be implemented in different forms, and exemplary embodiments will be explained in detail with reference to the accompanying drawings. However, the present disclosure should not be construed as being limited to the embodiments set forth herein. On the contrary, it should be understood that all modifications, equivalents and substitutions falling within the gist and technical scope of the present disclosure are included in the present disclosure.

[0037] The same reference numerals refer to the same elements throughout the text. For clarity, the size of the structure in the accompanying drawings may be enlarged. Terms such as first, second, etc. may be used to describe various elements herein, but the above elements should not be limited by the above terms. These terms are only used to distinguish one element from another element. For example, without departing from the scope of the present disclosure, a first component may be referred to as a second component, and similarly, a second component may be referred to as a first component. The singular form used herein includes the plural form unless the context clearly indicates otherwise.

[0038] Furthermore, in the present specification, terms such as “include” or “have” specify the presence of features, numbers, steps, operations, components, parts, or a combination thereof, and should not be interpreted as excluding the presence or possibility of addition of features, numbers, steps, operations, components, parts, or a combination thereof.

[0039] When describing a component of a layer, film, region (or zone), substrate, etc. in this specification as being "on" another component or "on the upper unit" of another component, such description includes not only the case where the component is directly on another component, but also the case where other components are present therebetween. In addition, when describing a component of a layer, film, region (or zone), substrate, etc. as being "under" another component or "under the lower unit" of another component, such description includes not only the case where the component is directly under another component, but also the case where other components are present therebetween. In addition, when describing a component "on" another component in this specification, such description also includes the case where the component is disposed on the lower unit of another component. In addition, it should also be understood that when an element or layer is referred to as being "between" two elements or layers, it can be the only element or layer between the two elements or layers, or there can also be one or more than one intervening elements or layers.

[0040] It should be understood that spatially relative terms are intended to encompass different orientations of the device when in use or operation in addition to the orientation depicted in the drawings. For example, if the device in the drawings is flipped, an element described as being "below" or "beneath" or "under" other elements or features will be oriented "above" the other elements or features. Thus, the exemplary terms "below" and "under" can encompass both the above and below directions. The device can be oriented in other ways (e.g., rotated 90 degrees or in other orientations), and the spatially relative descriptors used herein should be interpreted accordingly.

[0041] Processes, elements, and techniques that are not necessary for one of ordinary skill in the art may not be described for a complete understanding of the aspects and features of the present disclosure.

[0042] As used herein, the terms "substantially", "about" and similar terms are used as approximate terms rather than as terms of degree, and are intended to explain the inherent deviations in measured values ​​or calculated values ​​that would be recognized by those of ordinary skill in the art. In addition, when describing an embodiment of the present disclosure, the use of "may" refers to "one or more than one embodiment of the present disclosure". As used herein, the terms "use", "using" and "used" may be considered to be synonymous with the terms "utilize", "utilizing" and "utilized", respectively. In addition, the term "exemplary" is intended to refer to an instance or example.

[0043] The electronic device or electrical device and / or any other related device or component according to the embodiment of the present disclosure described herein can be implemented using any suitable hardware, firmware (e.g., application specific integrated circuit), software, or a combination of software, firmware and hardware. For example, the various components of these devices can be formed on an integrated circuit (IC) chip or on a separate IC chip. In addition, the various components of these devices can be implemented on a flexible printed circuit film, a tape carrier package (TCP), a printed circuit board (PCB), or formed on a substrate. In addition, the various components of these devices can be processes or threads running on one or more processors in one or more computing devices, which execute computer program instructions and interact with other system components for performing various functions described herein. Computer program instructions are stored in a memory, and the memory can be implemented in a computing device using a standard memory device (such as taking a random access memory (RAM) as an example). Computer program instructions can also be stored in other non-temporary computer-readable media, such as taking a CD-ROM, a flash drive, etc. as an example. Furthermore, those skilled in the art will recognize that the functionality of various computing devices may be combined or integrated into a single computing device, or the functionality of a particular computing device may be distributed across one or more than one other computing devices, without departing from the spirit and scope of the exemplary embodiments of the present disclosure.

[0044] Unless otherwise defined, all terms (including technical and scientific terms) used herein have the same meaning as commonly understood by those of ordinary skill in the art to which the present disclosure belongs. It should be further understood that terms, such as those defined in commonly used dictionaries, should be interpreted as having a meaning consistent with their meaning in the context of the relevant art and / or this specification, and should not be interpreted in an idealized or overly formal sense, unless explicitly defined as such herein.

[0045] Hereinafter, an organic electroluminescent device according to an embodiment of the present disclosure and an organic metal complex according to an embodiment of the present disclosure will be described with reference to the accompanying drawings.

[0046] Figures 1 to 4 is a cross-sectional view schematically showing an organic electroluminescent device 10 according to an embodiment of the present disclosure. Figures 1 to 4 , the organic electroluminescent device 10 may include a first electrode EL1 , a hole transport region HTR, a light emitting layer EML, an electron transport region ETR, and a second electrode EL2 , which are sequentially laminated.

[0047] The first electrode EL1 and the second electrode EL2 face each other, and a plurality of organic layers may be between the first electrode EL1 and the second electrode EL2. The plurality of organic layers may include a hole transport region HTR, an emission layer EML, and an electron transport region ETR. The organic electroluminescent device 10 according to the embodiment may include an organic metal complex in at least one of the plurality of organic layers, which will be described below.

[0048] When with Figure 1 When compared, Figure 2 1 shows a cross-sectional view of an organic electroluminescent device 10 according to an embodiment, wherein the hole transport region HTR includes a hole injection layer HIL and a hole transport layer HTL, and the electron transport region ETR includes an electron injection layer EIL and an electron transport layer ETL. Figure 1 When compared, Figure 3 A cross-sectional view of an organic electroluminescent device 10 according to an embodiment is shown, wherein the hole transport region HTR includes a hole injection layer HIL, a hole transport layer HTL and an electron blocking layer EBL, and the electron transport region ETR includes an electron injection layer EIL, an electron transport layer ETL and a hole blocking layer HBL. Figure 4 A cross-sectional view of the organic electroluminescent device 10 according to the embodiment is shown, in which a cover layer CPL is included on the second electrode EL2.

[0049] The first electrode EL1 has conductivity (e.g., electrical conductivity). The first electrode EL1 may be formed of a metal alloy or a conductive compound. The first electrode EL1 may be an anode. In addition, the first electrode EL1 may be a pixel electrode. The first electrode EL1 may be a transmissive electrode, a semi-transmissive reflective electrode, or a reflective electrode. When the first electrode EL1 is a transmissive electrode, the first electrode EL1 may include a transparent metal oxide, such as indium tin oxide (ITO), indium zinc oxide (IZO), zinc oxide (ZnO), indium tin zinc oxide (ITZO), and / or other suitable materials. When the first electrode EL1 is a semi-transmissive reflective electrode or a reflective electrode, the first electrode EL1 may include Ag, Mg, Cu, Al, Pt, Pd, Au, Ni, Nd, Ir, Cr, Li, Ca, LiF / Ca, LiF / Al, Mo, Ti, or a compound or mixture thereof (e.g., a mixture of Ag and Mg). In addition, the first electrode EL1 may have a multilayer structure including a reflective film or a semi-transmissive reflective film formed of the above-mentioned materials, and a transparent conductive film formed of indium tin oxide (ITO), indium zinc oxide (IZO), zinc oxide (ZnO), indium tin zinc oxide (ITZO) and / or other suitable materials. For example, the first electrode EL1 may have a three-layer structure of ITO / Ag / ITO, but is not limited thereto.

[0050] The thickness of the first electrode EL1 may be about to about For example, the thickness of the first electrode EL1 may be about to about

[0051] A hole transport region HTR is provided on the first electrode EL1. The hole transport region HTR may include at least one of a hole injection layer HIL, a hole transport layer HTL, a hole buffer layer, and an electron blocking layer EBL. The thickness of the hole transport region HTR may be, for example, about 100 Å. to about

[0052] The hole transport region HTR may have a single layer structure formed of a single material, a single layer structure formed of a plurality of different materials, or a multi-layer structure formed of a plurality of different materials.

[0053] For example, the hole transport region HTR may have a single layer structure of a hole injection layer HIL or a hole transport layer HTL, or may have a single layer structure formed of a hole injection material and a hole transport material. In addition, the hole transport region HTR may have a single layer structure formed of a plurality of different materials, or may have a laminated structure of a hole injection layer HIL / hole transport layer HTL, a hole injection layer HIL / hole transport layer HTL / hole buffer layer, a hole injection layer HIL / hole buffer layer, a hole transport layer HTL / hole buffer layer, or a hole injection layer HIL / hole transport layer HTL / electron blocking layer EBL (they are laminated in this order from the first electrode EL1), but the structure of the hole transport region HTR is not limited thereto.

[0054] The hole transport region HTR may be formed by using various suitable methods such as vacuum deposition, spin coating, casting, Langmuir-Blodgett (LB), inkjet printing, laser printing, laser induced thermal imaging (LITI), etc.

[0055] The hole injection layer HIL may include, for example, a phthalocyanine compound such as copper phthalocyanine and / or other suitable compounds; N,N'-diphenyl-N,N'-bis-[4-(phenyl-m-tolyl-amino)-phenyl]-biphenyl-4,4'-diamine (DNTPD), 4,4',4"-tris(3-methylphenylphenylamino)triphenylamine (m-MTDATA), 4,4',4"-tris(N,N-diphenylamino)triphenylamine (TDATA), 4,4',4"-tris{N-(2-naphthyl)-N-phenylamino}-triphenylamine (2-TNATA), poly(3,4-ethylenedioxythiophene) / poly(4-phenylene)triphenylamine (TDATA ... Poly(ethylene sulfonate) (PEDOT / PSS), polyaniline / dodecylbenzenesulfonic acid (PANI / DBSA), polyaniline / camphorsulfonic acid (PANI / CSA), polyaniline / poly(4-styrenesulfonate) (PANI / PSS), N,N'-di(naphthalene-1-yl)-N,N'-diphenyl-benzidine (NPB), triphenylamine-containing polyetherketone (TPAPEK), 4-isopropyl-4'-methyldiphenyliodonium tetrakis(pentafluorophenyl)borate, dipyrazino[2,3-f:-2',3'-h]quinoxaline-2,3,6,7,10,11-hexacarbonitrile (HAT-CN) and / or other suitable materials.

[0056] The hole transport layer HTL may include, for example, carbazole derivatives (e.g., N-phenylcarbazole, polyvinylcarbazole and / or other suitable materials), fluorene derivatives, triphenylamine derivatives (e.g., N,N'-bis(3-methylphenyl)-N,N'-diphenyl-[1,1'-biphenyl]-4,4'-diamine (TPD), 4,4',4"-tri(N-carbazolyl)triphenylamine (TCTA) and / or other suitable materials), N,N'-di(naphthalene-1-yl)-N,N'-diphenyl-benzidine (NPB), 4,4'-cyclohexylenebis[N,N-bis(4-methylphenyl)aniline] (TAPC), 4,4'-bis[N,N'-(3-tolyl)amino]-3,3'-dimethylbiphenyl, 1,3-bis(N-carbazolyl)benzene (mCP) and / or other suitable materials.

[0057] The thickness of the hole transport region HTR may be about to about For example, the thickness may be about to about The thickness of the hole injection layer HIL may be, for example, about to about And the thickness of the hole transport layer HTL may be about to about For example, the thickness of the electron blocking layer EBL may be about to about When the thicknesses of the hole transport region HTR, the hole injection layer HIL, the hole transport layer HTL, and the electron blocking layer EBL fall within the above-mentioned ranges, suitable or satisfactory hole transport characteristics may be obtained without a significant increase in driving voltage.

[0058] In addition to the materials mentioned above, the hole transport region HTR may further include a charge generating material for improving conductivity (e.g., electrical conductivity). The charge generating material may be uniformly or non-uniformly dispersed in the hole transport region HTR. The charge generating material may be, for example, a p-dopant. The p-dopant may be, but is not limited to, one of a quinone derivative, a metal oxide, and a compound containing a cyano group. Non-limiting examples of p-dopants may include, but are not limited to, quinone derivatives (e.g., tetracyanoquinodimethane (TCNQ), 2,3,5,6-tetrafluoro-7,7,8,8-tetracyanoquinodimethane (F4-TCNQ)), metal oxides (e.g., tungsten oxide and molybdenum oxide), and the like.

[0059] As mentioned above, in addition to the hole injection layer HIL and the hole transport layer HTL, the hole transport region HTR may further include at least one selected from a hole buffer layer and an electron blocking layer. The hole buffer layer may compensate for the resonance distance according to the wavelength of light generated in the light emitting layer EML, thereby increasing the luminous efficiency. The material contained in the hole transport region HTR may be contained in the hole buffer layer. The electron blocking layer is a layer for blocking electrons from entering the hole transport region HTR from the electron transport region ETR.

[0060] The light emitting layer EML is provided on the hole transport region HTR. The thickness of the light emitting layer EML may be, for example, about 100 Å. to about or about to about The light emitting layer EML may have a single layer structure formed using a single material, a single layer structure formed using a plurality of different materials, or a multilayer structure having a plurality of layers formed using a plurality of different materials.

[0061] The light-emitting layer EML of the organic electroluminescent device 10 according to the embodiment may include an organic metal complex. The organic metal complex according to the embodiment may include a metal atom as a central atom, a plurality of ligands connected to the metal atom, and a nitrogen atom connecting two of the plurality of ligands. For example, the metal atom may form a coordination bond with four ligands.

[0062] The organometallic complex according to the embodiment may include a nitrogen atom, which connects two of the multiple ligands and includes an aromatic ring group as a substituent. For example, the aromatic ring group may be a substituted or unsubstituted aryl group or a substituted or unsubstituted heteroaryl group. In some embodiments, the aromatic ring group may be a 6-membered ring group. For example, the aromatic ring group may be a substituted or unsubstituted phenyl group. In addition, the aromatic ring group may be a substituted or unsubstituted annular heteroaryl group having 2 or more carbon atoms. For example, the aromatic ring group may be a substituted or unsubstituted annular 6-membered heterocyclic group, which includes N as a heteroatom and has 2 or more carbon atoms.

[0063] The metal atom in the organic metal complex according to the embodiment may be Pt, Pd, Cu, Ag, Au, Rh, Ir, Ru, or Os. For example, the metal atom may be Pt.

[0064] One of the multiple ligands in the organic metal complex according to the embodiment may be a substituted or unsubstituted 5-membered heterocyclic group, or may be a substituted or unsubstituted cyclic C2-30 heteroaryl group. For example, one of the multiple ligands in the organic metal complex may be a substituted or unsubstituted 5-membered heterocyclic group having N as a heteroatom.

[0065] In addition, another of the multiple ligands connected to the metal atom can be a substituted or unsubstituted ring-forming C6-30 aryl group or a substituted or unsubstituted ring-forming C2-30 heteroaryl group. For example, another of the multiple ligands can be a substituted or unsubstituted pyridine or a substituted or unsubstituted benzene ring. In some embodiments, the substituted benzene ring can be a benzene ring substituted by a phenyl group, and the phenyl group is substituted by a 2,4,6-trimethyl group.

[0066] In the present disclosure, unless otherwise defined, the term "substituted or unsubstituted" may refer to being selected from the group consisting of deuterium atoms, halogen atoms, cyano groups, nitro groups, amino groups, silyl groups, oxy groups, sulfenyl groups, sulfinyl groups, sulfonyl groups, carbonyl groups, boron groups, phosphine oxide groups, phosphine sulfide groups, alkyl groups, alkenyl groups, alkoxy groups, hydrocarbon ring groups, aryl groups and heterocyclic groups. One or more than one substituents replace or are unsubstituted. In addition, each of the above-mentioned substituents can be substituted or unsubstituted. For example, a biphenyl group can be interpreted as an aryl group or a phenyl group substituted by a phenyl group. Heterocyclic groups include aliphatic heterocyclic groups and aromatic heterocyclic groups (heteroaryl groups).

[0067] In the present disclosure, examples of the halogen atom are a fluorine atom, a chlorine atom, a bromine atom or an iodine atom.

[0068] In the present disclosure, the alkyl group may have a straight chain form, a branched chain form or a cyclic form. The number of carbon atoms contained in the alkyl group may be 1 to 30, 1 to 20, 1 to 10 or 1 to 5. Examples of the alkyl group may include a methyl group, an ethyl group, an n-propyl group, an isopropyl group, a n-butyl group, a sec-butyl group, a tert-butyl group, an isobutyl group, a 2-ethylbutyl group, a 3,3-dimethylbutyl group, an n-pentyl group, an isopentyl group, a neopentyl group, a tert-pentyl group, a cyclopentyl group, a 1-methylpentyl group, a 3-methylpentyl group, a 2-ethylpentyl group, a 4-methyl-2-pentyl group, an n-hexyl group, a 1-methylhexyl group, a 2-ethylhexyl group, a 4-tert-butylcyclohexyl group, an n-heptyl group, a 1-methylheptyl group, a 2,2-dimethylheptyl group, a 2-ethylheptyl group, a 2-butylheptyl group, an n-octyl group, a tert-octyl group, a 2-ethyloctyl group, a 2-butyloctyl group, a 2-hexyloctyl group, a 3,7-dimethyloctyl group, a cyclooctyl group, an n-nonyl group, an n-decyl group, an adamantyl group, a 2-ethyldecyl group The invention also includes but is not limited to a 2-butyldecyl group, a 2-hexyldecyl group, a 2-octyldecyl group, an n-undecyl group, an n-dodecyl group, a 2-ethyldodecyl group, a 2-butyldodecyl group, a 2-hexyldodecyl group, a 2-octyldodecyl group, an n-tridecyl group, an n-tetradecyl group, an n-pentadecyl group, an n-hexadecyl group, a 2-ethylhexadecyl group, a 2-butylhexadecyl group, a 2-hexylhexadecyl group, a 2-octylhexadecyl group, an n-heptadecyl group, an n-octadecyl group, an n-nonadecyl group, an n-eicosyl group, a 2-ethyleicosyl group, a 2-butyleicosyl group, a 2-hexyleicosyl group, a 2-octyleicosyl group, an n-heneicosyl group, an n-docosyl group, an n-tricosyl group, an n-tetracosyl group, an n-pentacosyl group, an n-hexacosyl group, an n-heptacosyl group, an n-octacosyl group, an n-nonacosyl group, and an n-triacontyl group.

[0069] In the present disclosure, an aryl group refers to a functional group or a substituent derived from an aromatic hydrocarbon ring. The aryl group may be a monocyclic aryl group or a polycyclic aryl group. The number of ring carbon atoms contained in the aryl group may be 6 to 60, 6 to 30, 6 to 20, or 6 to 15. Examples of aryl groups may include phenyl groups, naphthyl groups, fluorenyl groups, anthracenyl groups, phenanthrenyl groups, biphenyl groups, terphenyl groups, quaterphenyl groups, pentaphenyl groups, hexaphenyl groups, biphenylene groups, triphenylenyl groups, pyrenyl groups, benzofluoranthenyl groups, and group, etc., but are not limited thereto.

[0070] In the present disclosure, the heteroaryl group may contain one or more than one B, O, N, P, Si or S as a heteroatom. When the heteroaryl group contains two or more than two heteroatoms, the two or more than two heteroatoms may be the same or different. The heteroaryl group may be a monocyclic heterocyclic group or a polycyclic heterocyclic group. The number of ring carbon atoms contained in the heteroaryl group may be 2 to 30, 2 to 20 or 2 to 10. Examples of the heteroaryl group may include a thienyl group, a furanyl group, a pyrrolyl group, an imidazolyl group, a thiazolyl group, an oxazolyl group, an oxadiazolyl group, a triazolyl group, a pyridyl group, a bipyridyl group, a pyrimidyl group, a triazinyl group, an acridinyl group, a pyridazinyl group, a pyrazinyl group, a quinolyl group, a quinazolinyl group, a quinoxalinyl group, a phenoxazinyl group, a phthalazinyl group, a pyridopyrimidinyl group, a pyridopyrazinyl group, a pyrazinopyrazinyl group, an isoquinolyl group, and a pyridopyrimidinyl group. The invention also includes, but is not limited to, a quinoline group, an indolyl group, a carbazolyl group, an N-arylcarbazolyl group, an N-heteroarylcarbazolyl group, an N-alkylcarbazolyl group, a benzoxazolyl group, a benzimidazolyl group, a benzothiazolyl group, a benzocarbazolyl group, a benzothiophenyl group, a dibenzothiophenyl group, a thienothiphenyl group, a benzofuranyl group, a phenanthroline group, an isoxazolyl group, a thiadiazolyl group, a phenothiazinyl group, a dibenzosilyl group, and a dibenzofuranyl group.

[0071] In the present disclosure, the expression "bonding to an adjacent group to form a ring" may refer to bonding to an adjacent group to form a substituted or unsubstituted hydrocarbon ring or a substituted or unsubstituted heterocyclic ring. The hydrocarbon ring includes an aliphatic hydrocarbon ring and an aromatic hydrocarbon ring. The heterocyclic ring includes an aliphatic heterocyclic ring and an aromatic heterocyclic ring. The hydrocarbon ring and the heterocyclic ring may be monocyclic or polycyclic. In addition, the ring formed by bonding to each other may be bonded to another ring to form a spiro structure.

[0072] In the present disclosure, the term "adjacent group" may refer to a substituent that replaces an atom directly connected to the atom substituted by the corresponding substituent, another substituent that replaces the atom substituted by the corresponding substituent, or a substituent that is spatially located at the nearest position to the corresponding substituent. For example, in 1,2-dimethylbenzene, two methyl groups may be interpreted as "adjacent groups" to each other, and in 1,1-diethylcyclopentane, two ethyl groups may be interpreted as "adjacent groups" to each other.

[0073] In this disclosure, Refers to the location where it connects to the adjacent part.

[0074] The light emitting layer EML of the organic electroluminescent device 10 according to the embodiment may include an organic metal complex represented by Formula 1 below.

[0075] Formula 1

[0076]

[0077] In the above Formula 1, M is Pt, Pd, Cu, Ag, Au, Rh, Ir, Ru, or Os. For example, M may be Pt.

[0078] L 1 is a substituted or unsubstituted 5-membered heterocyclic group or a substituted or unsubstituted cyclic C2-30 heteroaryl group. 1 It may be a substituted or unsubstituted 5-membered heterocyclic group containing N as a heteroatom.

[0079] L 2 , L 3 and L 4 Each is independently a substituted or unsubstituted cyclic C6-30 aryl group or a substituted or unsubstituted cyclic C2-30 heteroaryl group. 2 and L 3 When L is an aryl group, the aryl group may be a 6-membered ring, such as a substituted or unsubstituted benzene ring. 4 When a heteroaryl group, the heteroaryl group may contain N in an aromatic 6-membered ring and may be, for example, pyridine.

[0080] R 1 , R 2 , R 3 and R 4 are each independently a hydrogen atom, a deuterium atom, a halogen atom, a substituted or unsubstituted cyclic C6-30 aryl group, a substituted or unsubstituted cyclic C6-30 heteroaryl group, a substituted or unsubstituted C1-30 alkyl group, a substituted or unsubstituted C2-30 alkenyl group, a substituted or unsubstituted C2-30 alkynyl group, a substituted or unsubstituted amino group, a carbonyl group, a hydroxyl group, a thiol group, a nitrile group, a cyano group, a C1-30 alkoxy group, an ester group, a sulfonic acid group, a carboxyl group or a silyl group, and R 1 , R 2 , R 3 and R 4 At least some of may be bonded to adjacent groups to form a ring. 1 , R 2 , R 3 and R 4 Each is independently a substituted or unsubstituted methyl group or a substituted or unsubstituted phenyl group.

[0081] In some embodiments, when R 1 , R 2 , R 3 and R 4 When at least some of R1 , R 2 , R 3 and R 4 Not bound to as connected L 3 and L 4 In other words, R 1 , R 2 , R 3 and R 4 Not bonded to Y contained in the aromatic ring 1 To Y 5 , and is not bonded to R which is a substituent of the aromatic ring group 5 For example, R 1 Can be combined with R 2 and / or R 4 . R 2 Can be combined with R 1 and / or R 3 . R 3 Can be combined with R 2 . R 4 Can be combined with R 1 .

[0082] R 5 is a hydrogen atom, a deuterium atom, a halogen atom, a substituted or unsubstituted cyclic C6-30 aryl group, a substituted or unsubstituted cyclic C6-30 heteroaryl group, a substituted or unsubstituted C1-30 alkyl group, a substituted or unsubstituted C2-30 alkenyl group, a substituted or unsubstituted C2-30 alkynyl group, a substituted or unsubstituted amino group, a carbonyl group, a hydroxyl group, a thiol group, a nitrile group, a cyano group, a C1-30 alkoxy group, an ester group, a sulfonic acid group, a carboxyl group or a silyl group, and in the case of a plurality of R 5 In the case of multiple R 5 can combine with each other to form a ring. For example, R 5 It may be a substituted or unsubstituted phenyl group, a substituted or unsubstituted dibenzofuran or a substituted or unsubstituted naphthyl group.

[0083] n 1 to n 4 can each independently be an integer from 0 to 3. 1 When it is an integer of 2 or greater, multiple R 1 can be the same or different from each other. 2 When it is an integer of 2 or greater, multiple R 2 can be the same or different from each other. 3 When it is an integer of 2 or greater, multiple R 3 can be the same or different from each other. 4 When it is an integer of 2 or greater, multiple R4 can be the same or different from each other. For example, n 1 to n 4 Can be 1.

[0084] n 5 It can be an integer from 0 to 5. 5 When it is an integer of 2 or greater, multiple R 5 May be the same as or different from each other.

[0085] Y 1 , Y 2 , Y 3 , Y 4 and Y 5 can each independently be C, N, O or S. For example, Y 1 , Y 2 , Y 3 , Y 4 and Y 5 At least two of them can be C.

[0086] A 1 Can be *-O-*, *-S-*, *-S(=O)-*, *-SO 2 -*、*-Se-*、*-NR 11 -*、*-R 11 P=O-*、*-CR 12 R 13 -*,*-C(=O)-*,*-SiR 12 R 13 -*、*-GeR 12 R 13 -*, *-BH-*, *-P(O)H-*, *-PH-*, *-NH-*, *-CR 12 H-*、*-CH 2 -*、*-SiH 2 -*、*-SiHR 12 -*、*-BR 14 -*or*-PR 14 -*. For example, A 1 Can be *-O-* or *-NR 11 -*.

[0087] R 11 , R 12 , R 13 and R 14Each of them may be independently a hydrogen atom, a deuterium atom, a halogen atom, a substituted or unsubstituted cyclic C6-30 aryl group, a substituted or unsubstituted cyclic C6-30 heteroaryl group, a substituted or unsubstituted C1-30 alkyl group, a substituted or unsubstituted C2-30 alkenyl group, a substituted or unsubstituted C2-30 alkynyl group, a substituted or unsubstituted amino group, a carbonyl group, a hydroxyl group, a thiol group, a nitrile group, a cyano group, a C1-30 alkoxy group, an ester group, a sulfonic acid group, a carboxyl group or a silyl group, and may be bonded to an adjacent group to form a ring. For example, R 11 The phenyl group may be substituted or unsubstituted.

[0088] Formula 1-1

[0089]

[0090] The above formula 1-1 represents Formula 1 in which M is Pt.

[0091] In the above formula 1-1, L 1 To L 4 , R 1 To R 5 、n 1 to n 5 , A 1 , R 11 To R 14 and Y 1 To Y 5 The same as those explained with reference to Formula 1 may be used.

[0092] In the organic metal complex according to the embodiment, the organic metal complex represented by the above Formula 1 may be represented by the following Formula 1-2.

[0093] Formula 1-2

[0094]

[0095] Formula 1-2 represents that L 2 and L 3 Benzene, L 4 is pyridine and Y 1 To Y 5 It is the formula 1 of C.

[0096] In the above formula 1-2, M, L 1 , R 1 To R 5 、n 1 to n 5 , A 1 and R 11 To R 14 The same as those explained with reference to Formula 1 may be used.

[0097] Among the organic metal complexes according to the embodiment, the organic metal complex represented by the above Formula 1 may be represented by the following Formulas 1-3.

[0098] Formula 1-3

[0099]

[0100] The above formula 1-3 represents formula 1-2 in which M is Pt.

[0101] In the above formula 1-3, L 1 , R 1 To R 5 、n 1 to n 5 , A 1 and R 11 To R 14 The same as those explained with reference to Formula 1 may be used.

[0102] Among the organic metal complexes according to the embodiment, the organic metal complex represented by the above Formula 1 may include at least one of compounds represented by the following Compound Group 1.

[0103] Compound Group 1

[0104]

[0105] exist Figures 1 to 4 In the organic electroluminescent device 10 according to the embodiment illustrated in , the emission layer EML may include a host material and a dopant material, and the emission layer EML may include the organic metal complex represented by Formula 1 as the dopant material.

[0106] The organic metal complex according to the embodiment may be a phosphorescent dopant. The emission layer EML may emit light through phosphorescent emission.

[0107] The light emitting layer EML may include one or more than one organic metal complexes of the above-mentioned compound group. In addition to the above-mentioned organic metal complexes, the light emitting layer EML may include any suitable material available in the art.

[0108] The light-emitting layer EML may adopt any suitable material available in the relevant field as a host material, but is not limited. For example, the light-emitting layer EML may include at least one of bis[2-(diphenylphosphino)phenyl]ether oxide (DPEPO), 4,4'-bis(carbazole-9-yl)biphenyl, 1,3-bis(carbazole-9-yl)benzene (mCP), 2,8-bis(diphenylphosphino)dibenzo[b,d]furan (PPF), 4,4',4"-tri(carbazole-9-yl)-triphenylamine (TCTA) and 1,3,5-tri(N-phenylbenzimidazol-2-yl)benzene (TPBi), but the example is not limited thereto. For example, the light-emitting layer EML may further include tris(8-hydroxyquinolinolato)aluminum (Alq) as a host material. 3 )、4,4'-bis(N-carbazolyl)-1,1'-biphenyl (CBP), poly(N-vinylcarbazole) (PVK), 9,10-di(naphthalene-2-yl)anthracene (ADN), 3-tert-butyl-9,10-di(naphthalene-2-yl)anthracene (TBADN), distyryl arylide (DSA), 4,4'-bis(9-carbazolyl)-2,2'-dimethyl-biphenyl (CDBP), 2-methyl-9,10-bis(naphthalene-2-yl)anthracene (MADN), hexaphenylcyclotriphosphazene (CP1), 1,4-bis(triphenylsilyl)benzene (UGH2), hexaphenylcyclotrisiloxane (DPSiO3), octaphenylcyclotetrasiloxane (DPSiO4), etc.

[0109] The light emitting layer EML of the organic electroluminescent device 10 according to the embodiment may further include any suitable dopant material available in the art, in addition to the above-mentioned organic metal complex according to the embodiment.

[0110] The light-emitting layer EML according to the embodiment may further include a styryl derivative (e.g., 1,4-bis[2-(3-N-ethylcarbazolyl)vinyl]benzene (BCzVB), 4-(di-p-tolylamino)-4'-[(di-p-tolylamino)styryl]diphenylethylene (DPAVB), N-(4-((E)-2-(6-((E)-4-(diphenylamino)styryl)naphthalene-2-yl)vinyl)phenyl)-N-phenylaniline (N-BDAVBi)), perylene and its derivatives (e.g., 2,5,8,11-tetra-tert-butylperylene (TBP)), pyrene and its derivatives (e.g., 1,1-dipyrene, 1,4-dipyrenylbenzene, 1,4-bis(N,N-diphenylamino)pyrene) and / or other suitable materials.

[0111] exist Figures 1 to 3In the organic electroluminescent device 10 according to the embodiment illustrated in FIG, an electron transport region ETR is provided on the emission layer EML. The electron transport region ETR may include any one of a hole blocking layer HBL, an electron transport layer ETL, and an electron injection layer EIL, but the embodiment is not limited thereto.

[0112] The electron transport region ETR may have a single layer structure formed using a single material, a single layer structure formed using a plurality of different materials, or a multi-layer structure formed using a plurality of different materials.

[0113] For example, the electron transport region ETR may have a single layer structure of an electron injection layer EIL or an electron transport layer ETL, or a single layer structure formed using an electron injection material and an electron transport material. In addition, the electron transport region ETR may have a single layer structure formed using a plurality of different materials, or have a structure of an electron transport layer ETL / electron injection layer EIL, or a hole blocking layer HBL / electron transport layer ETL / electron injection layer EIL (they are laminated in this order from the light emitting layer EML), but the structure of the electron transport region ETR is not limited thereto. For example, the thickness of the electron transport region ETR may be about 1000 Å. to about

[0114] The electron transport region ETR may be formed by using various suitable methods such as vacuum deposition, spin coating, casting, Langmuir-Blodgett (LB), inkjet printing, laser printing, laser induced thermal imaging (LITI), etc.

[0115] When the electron transport region ETR includes an electron transport layer ETL, the electron transport layer ETL may include, but is not limited to, an anthracene-based compound. The electron transport layer ETL may include, for example, tris(8-hydroxyquinolinato)aluminum (Alq 3), 1,3,5-tris[(3-pyridyl)-phenyl-3-yl]benzene, 2,4,6-tris(3'-(pyridin-3-yl)biphenyl-3-yl)-1,3,5-triazine, 2-(4-(N-phenylbenzimidazol-1-yl)phenyl)-9,10-dinaphthylanthracene, 1,3,5-tris(1-phenyl-1H-benzo[d]imidazol-2-yl)benzene (TPBi), 2,9-dimethyl-4,7-diphenyl-1,10-phenanthroline (BCP), 4,7-diphenyl-1,10-phenanthroline (Bphen), 3-(4-biphenyl)- 4-phenyl-5-tert-butylphenyl-1,2,4-triazole (TAZ), 4-(naphthalene-1-yl)-3,5-diphenyl-4H-1,2,4-triazole (NTAZ), 2-(4-biphenyl)-5-(4-tert-butylphenyl)-1,3,4-oxadiazole (tBu-PBD), bis(2-methyl-8-quinolinolato-N1,O8)-(1,1'-biphenyl-4-ato)aluminum (BAlq), bis(benzoquinolin-10-ato)beryllium (Bebq2), 9,10-di(naphthalene-2-yl)anthracene (ADN), or a mixture thereof. The thickness of the electron transport layer ETL may be about 1000 nm. to about For example, the thickness may be about to about When the thickness of the electron transport layer ETL falls within the above-mentioned range, suitable or satisfactory electron transport characteristics may be obtained without a significant increase in driving voltage.

[0116] When the electron transport region ETR includes an electron injection layer EIL, the electron injection layer EIL may be made of metal halides (such as LiF, NaCl, CsF, RbCl, and RbI), lanthanide metals (such as Yb), metal oxides (such as Li 2 O and BaO) or lithium quinoline (LiQ), but the example is not limited thereto. The electron injection layer EIL may be formed of a mixture of an electron injection material and an organic metal salt having an insulating property. The organic metal salt may be a material having an energy band gap of 4 eV or greater. For example, the organic metal salt may include a metal acetate, a metal benzoate, a metal acetoacetate, a metal acetylacetonate, or a metal stearate. The thickness of the electron injection layer EIL may be about 1000 Å. to about or about to about When the thickness of the electron injection layer falls within the above-mentioned range, suitable or satisfactory electron injection characteristics may be obtained without a significant increase in driving voltage.

[0117] As mentioned above, the electron transport region ETR may include a hole blocking layer HBL. For example, the hole blocking layer may include at least one of 2,9-dimethyl-4,7-diphenyl-1,10-phenanthroline (BCP) and 4,7-diphenyl-1,10-phenanthroline (Bphen), but examples are not limited thereto.

[0118] A second electrode EL2 is provided on the electron transport region ETR. The second electrode EL2 may be a common electrode or a cathode. The second electrode EL2 may be a transmissive electrode, a semi-transmissive reflective electrode or a reflective electrode. When the second electrode EL2 is a transmissive electrode, the second electrode EL2 may be formed of a transparent metal oxide such as indium tin oxide (ITO), indium zinc oxide (IZO), zinc oxide (ZnO), indium tin zinc oxide (ITZO) and / or other suitable materials.

[0119] When the second electrode EL2 is a semi-transmissive reflective electrode or a reflective electrode, the second electrode EL2 may include Ag, Mg, Cu, Al, Pt, Pd, Au, Ni, Nd, Ir, Cr, Li, Ca, LiF / Ca, LiF / Al, Mo, Ti, or a compound or mixture thereof (e.g., a mixture of Ag and Mg). In some embodiments, the second electrode EL2 may have a multilayer structure including a reflective film or a semi-transmissive reflective film formed of the above materials, and a transparent conductive film formed of indium tin oxide (ITO), indium zinc oxide (IZO), zinc oxide (ZnO), indium tin zinc oxide (ITZO) and / or other suitable materials.

[0120] In some embodiments, the second electrode EL2 may be connected to an auxiliary electrode. When the second electrode EL2 is connected to the auxiliary electrode, the resistance of the second electrode EL2 may be reduced.

[0121] like Figure 4 As shown in FIG. 1 , a cover layer CPL may be further formed on the second electrode EL2 of the organic electroluminescent device 10 according to the embodiment. The cover layer CPL may include, for example, α-NPD, NPB, TPD, m-MTDATA, Alq 3 , CuPc, N4,N4,N4',N4'-tetrakis(biphenyl-4-yl)biphenyl-4,4'-diamine (TPD15), 4,4',4"-tris(carbazol-9-yl)triphenylamine (TCTA) and / or other suitable materials.

[0122] The organic electroluminescent device 10 according to an embodiment of the present disclosure may include the above-mentioned organic metal complex in at least one of the organic layers between the first electrode EL1 and the second electrode EL2 or in the cover layer CPL on the second electrode EL2 .

[0123] In the organic electroluminescent device 10, when a voltage is applied to each of the first electrode EL1 and the second electrode EL2, holes injected from the first electrode EL1 move to the light-emitting layer EML via the hole transport region HTR, and electrons injected from the second electrode EL2 move to the light-emitting layer EML via the electron transport region ETR. The electrons and holes are recombined in the light-emitting layer EML to generate excitons, and light is emitted when the excitons drop (e.g., transition) from an excited state to a ground state.

[0124] The above explanation about the organic electroluminescent device 10 according to the embodiment mainly focuses on the embodiment in which the organic metal complex according to the embodiment is included in the light-emitting layer EML. However, the present disclosure is not limited thereto. The organic metal complex may be included in at least one of the other organic layers, or in the cover layer CPL on the second electrode EL2. For example, the organic metal complex may be included in the hole transport region HTR or the electron transport region ETR.

[0125] According to the embodiment, the organic electroluminescent device 10 includes an organic metal complex of the light-emitting layer EML, the organic metal complex including a metal atom as a central atom, a plurality of ligands connected to the metal atom, and a nitrogen atom connecting any two of the plurality of ligands. Because the organic metal complex has a structure in which the nitrogen atom includes an aromatic ring group as a substituent and the aromatic ring group is not bonded to a plurality of ligands to form a ring, the nitrogen atom can increase the binding stability between the central atom and the ligand. Therefore, compared with the case in which the aromatic ring group replacing the nitrogen atom forms a ring with other ligands, the organic electroluminescent device according to the embodiment of the present disclosure can have an improved lifespan and a lower driving voltage characteristic.

[0126] Hereinafter, an organic metal complex according to an embodiment of the present disclosure, an organic electroluminescent device 10 according to an embodiment, and an organic metal complex for the organic electroluminescent device 10 will be specifically described with reference to Examples and Comparative Examples. In addition, the following examples are provided only to help understanding of the present disclosure, and the scope of the present disclosure is not limited thereto.

[0127] Example

[0128] 1. Synthesis of organometallic complexes.

[0129] The organic metal complex according to an embodiment of the present disclosure may be synthesized, for example, as follows. However, the synthesis of the organic metal complex according to an embodiment of the present disclosure is not limited thereto.

[0130] Synthesis Example 1: Synthesis of Compound 1

[0131]

[0132] 1) Synthesis of intermediate [1-A]

[0133] Aniline 1.00 g (10.7 mmol), 2-bromopyridine 1.70 g (10.7 mmol), PdCl 2 (dppf)([1,1'-bis(diphenylphosphino)ferrocene]dichloropalladium(II)) 782.9 mg (1.07 mmol) and NaOt-Bu 1.54 g (16.5 mmol) were suspended in 100 ml of dioxane solvent, heated to about 100° C. and stirred for about 12 hours. The reaction compound was extracted with dichloromethane and distilled water. The obtained organic layer was washed three times with distilled water, dried with magnesium sulfate, filtered and concentrated under reduced pressure. The concentrate was separated by column chromatography to obtain intermediate [1-A] with a yield of 70%.

[0134] 2) Synthesis of intermediate [1-B]

[0135] The synthesized intermediate [1-A], 1-bromo-3-iodobenzene (1.0 equivalent), PdCl 2 (dppf) (0.1 equivalent) and NaOt-Bu (1.5 equivalent) were suspended in 100 ml of dioxane solvent, heated to about 100 ° C and stirred for about 12 hours. The reaction compound was extracted with dichloromethane and distilled water. The obtained organic layer was washed three times with distilled water, dried with magnesium sulfate, filtered and concentrated under reduced pressure. The concentrate was separated by column chromatography to obtain intermediate [1-B] with a yield of 70%.

[0136] 3) Synthesis of intermediate [1-C]

[0137] The synthesized intermediate [1-B], 3-(1H-imidazole-1-yl)phenol (1.0 equivalent), cuprous iodide (0.1 equivalent), potassium phosphate (2.0 equivalent) and L-proline (0.1 equivalent) were suspended in 100 ml of a dimethylformamide solvent, heated to about 120° C. and stirred for about 12 hours. The reaction compound was extracted using dichloromethane and distilled water. The obtained organic layer was washed three times with distilled water, dried with magnesium sulfate, filtered and concentrated under reduced pressure. The concentrate was separated by column chromatography to obtain an intermediate [1-C] in a 70% yield.

[0138] 4) Synthesis of intermediate [1-D]

[0139] The synthesized intermediate [1-C] was dissolved in acetone, methyl iodide (1.2 equivalents) was added thereto, and stirred at room temperature for about 24 hours. After the reaction was terminated, the pressure was reduced to remove the solvent, and the concentrate was separated by column chromatography to obtain the intermediate [1-D] in 80% yield.

[0140] 5) Synthesis of intermediate [1-E]

[0141] The synthesized intermediate [1-D] was dissolved in a solvent mixture of methanol and distilled water (4:1), and ammonium hexafluorophosphate (2 equivalents) was added thereto. The resulting solid was stirred at room temperature for about 12 hours. The solid was filtered and washed with ether to obtain intermediate [1-E] in 90% yield.

[0142] 6) Synthesis of Compound 1

[0143] The synthesized intermediate [1-E], sodium acetate (3.0 equivalents) and Pt(COD)Cl 2 (Dichloro(1,5-cyclooctadiene)platinum(II)) (1.1 equivalents) was suspended in 1,4-dioxane solvent. The reaction mixture was heated to about 120° C. and stirred for about 12 hours. After the reaction was terminated, the pressure was reduced to remove the solvent, and the concentrate was separated by column chromatography to obtain Compound 1 in 40% yield.

[0144] Synthesis Example 2: Synthesis of Compound 2

[0145] Compound 2 was obtained by using substantially the same method as in Synthesis Example 1 except that [1,1′-biphenyl]-2-amine was used instead of aniline.

[0146] Synthesis Example 3: Synthesis of Compound 3

[0147] Compound 3 was obtained by using substantially the same method as in Synthesis Example 1 except that [1,1′-biphenyl]-3-amine was used instead of aniline.

[0148] Synthesis Example 4: Synthesis of Compound 4

[0149] Compound 4 was obtained by using substantially the same method as in Synthesis Example 1 except that [1,1′-biphenyl]-4-amine was used instead of aniline.

[0150] Synthesis Example 5: Synthesis of Compound 5

[0151] Compound 5 was obtained by using substantially the same method as in Synthesis Example 1 except that 2-(naphthalen-1-yl)aniline was used instead of aniline.

[0152] Synthesis Example 6: Synthesis of Compound 6

[0153] Compound 6 was obtained by using substantially the same method as in Synthesis Example 1 except that 2-(naphthalen-1-yl)aniline was used instead of aniline.

[0154] Synthesis Example 7: Synthesis of Compound 7

[0155] Compound 7 was obtained by using essentially the same method as in Synthesis Example 1, except that [1,1'-biphenyl]-2-amine was used instead of aniline, 2-bromo-4-(tert-butyl)pyridine was used instead of 2-bromopyridine, and 1-(5-bromo-2',4',6'-trimethyl-[1,1'-biphenyl]-3-yl)-1H-imidazole was used instead of 3-(1H-imidazole-1-yl)phenol.

[0156] Synthesis Example 8: Synthesis of Compound 8

[0157] Compound 8 was obtained by using substantially the same method as in Synthesis Example 1, except that [1,1′-biphenyl]-2-amine was used instead of aniline, and 1-(3-bromophenyl)-1H-benzo[d]imidazole was used instead of 3-(1H-imidazol-1-yl)phenol.

[0158] Synthesis Example 9: Synthesis of Compound 9

[0159] Compound 9 was obtained by using substantially the same method as in Synthesis Example 1, except that [1,1′-biphenyl]-2-amine was used instead of aniline, and N-(3-(1H-imidazol-1-yl)phenyl)-[1,1′-biphenyl]-2-amine was used instead of 3-(1H-imidazol-1-yl)phenol.

[0160] Synthesis Example 10: Synthesis of Compound 10

[0161] Compound 10 was obtained by using substantially the same method as in Synthesis Example 1, except that [1,1′-biphenyl]-2-amine was used instead of aniline, and N-(3-(1H-imidazol-1-yl)phenyl)-[1,1′-biphenyl]-2-amine was used instead of 3-(1H-imidazol-1-yl)phenol.

[0162] Synthesis Example 11: Synthesis of Compound 11

[0163] Compound 11 was obtained by using substantially the same method as in Synthesis Example 1 except that [1,1′-biphenyl]-2-amine was used instead of aniline, and 3-(3-bromophenyl)-3H-1,3-oxazole was used instead of 3-(1H-imidazol-1-yl)phenol.

[0164] Synthesis Example 12: Synthesis of Compound 12

[0165] Compound 12 was obtained by using substantially the same method as in Synthesis Example 1 except that [1,1′-biphenyl]-2-amine was used instead of aniline, and 1-(3-bromophenyl)-1H-1,2,4-triazole was used instead of 3-(1H-imidazol-1-yl)phenol.

[0166] Synthesis Example 13: Synthesis of Compound 13

[0167] Compound 13 was obtained by using substantially the same method as in Synthesis Example 1, except that dibenzo[b,d]furan-4-amine was used instead of aniline, and N-(3-(1H-benzo[d]imidazol-1-yl)phenyl)-[1,1'-biphenyl]-2-amine was used instead of 3-(1H-imidazol-1-yl)phenol.

[0168] Synthesis Example 14: Synthesis of Compound 14

[0169] Compound 14 was obtained by using substantially the same method as in Synthesis Example 1, except that 9-methyl-9H-carbazole-1-amine was used instead of aniline, and N-(3-(1H-benzo[d]imidazol-1-yl)phenyl)-[1,1′-biphenyl]-2-amine was used instead of 3-(1H-imidazol-1-yl)phenol.

[0170] 1H NMR and MS / FAB of the synthesized compounds are shown in Table 1 below.

[0171] Table 1

[0172]

[0173]

[0174]

[0175] 2. Calculation of energy levels of organometallic complexes.

[0176] The energy levels of the organometallic complexes of Example Compound 1, Example Compound 2, Example Compound 3, Example Compound 8, and Comparative Example Compound C1 were measured and are shown in Table 2 below.

[0177] Example compounds

[0178]

[0179] Comparative Example Compound C1

[0180]

[0181] Table 2

[0182]

[0183] It can be confirmed that the example compounds of Compound 1, Compound 2, Compound 3 and Compound 8 have similar central emission wavelengths to that of Comparative Example Compound C1, but have increased metal-to-ligand charge transfer ( 3 MLCT) ratio and metal neutrality ( 3MC). In addition, it can be confirmed that the Example compound has an increased bond dissociation energy compared to the Comparative Example Compound C1. Therefore, when the Example compound is used in a light-emitting device, improved device life and luminous efficiency can be expected.

[0184] 3. Fabrication and evaluation of organic electroluminescent devices containing organometallic complexes.

[0185] Fabrication of organic electroluminescent devices

[0186] The organic electroluminescent device according to the embodiment including the organic metal complex according to the embodiment is manufactured by using the method described below.

[0187] Example 1

[0188] For the substrate and anode, Corning 15Ω / cm 2 The ITO glass substrate was cut into a size of 50 mm×50 mm×0.7 mm, and cleaned by ultrasonic treatment in isopropyl alcohol and deionized water for 5 minutes each, cleaned in UV ozone for 30 minutes, and placed on a vacuum deposition apparatus.

[0189] On the upper surface of the ITO anode formed on the upper glass substrate, a 2-TNATA layer having a thickness of about 100 nm was formed by vacuum depositing 2-TNATA. A hole injection layer having a thickness of about 1000 mm was formed on the upper surface of the hole injection layer by vacuum depositing NPB. The hole transport layer has a thickness of .

[0190] The hole transport layer was formed by vacuum depositing BCPDS and POPCPA as co-host materials (the weight ratio of BCPDS to POPCPA was 90:10) and compound 1 as a dopant material on the upper surface of the hole transport layer to form a porous structure having a thickness of about 100 nm. The weight ratio of the co-host material and the dopant material is about 90:10.

[0191] The organic electroluminescent device is manufactured by depositing TSPO1 on the upper surface of the light emitting layer to form a A hole blocking layer of thickness is formed by depositing Alq 3 Formed with approximately Then, an electron transport layer having a thickness of about 1000 nm is formed by depositing LiF on the upper surface of the electron transport layer. An electron injection layer having a thickness of about 1000 mm was formed by vacuum depositing Al on the upper surface of the electron injection layer. The thickness of the cathode.

[0192]

[0193] Examples 2 to 4 and Comparative Example 1

[0194] An organic electroluminescent device was manufactured by using substantially the same method as in Example 1, except that when forming the light-emitting layer, the compounds exemplified in Table 2 were used instead of Compound 1 as a dopant material, respectively.

[0195] Characteristic evaluation of organic electroluminescent devices

[0196] Table 3

[0197]

[0198] Table 3 illustrates the evaluation results of the organic electroluminescent devices of Examples 1 to 4 and Comparative Example 1. Table 3 illustrates the driving voltage, current density, luminous efficiency and life of the manufactured organic electroluminescent devices for comparison with each other. The luminous efficiency represents the driving voltage, current density, luminous efficiency and life of the organic electroluminescent devices for 50 mA / cm 2 The lifetime is measured by measuring the time it takes for the initial brightness to decrease by 95% (half-life).

[0199] Referring to Table 3, compared with the organic electroluminescent device of Comparative Example 1, the organic electroluminescent devices of Examples 1 to 4 have lower driving voltages and increased luminous efficiency and lifespan.

[0200] When referring to the evaluation results of the compounds and organic electroluminescent devices of the examples, it can be confirmed that the compounds in the embodiments each have a metal atom as a central atom, include nitrogen atoms connected to two of the multiple ligands connected to the metal atom, wherein the nitrogen atom includes an aromatic ring group as a substituent, and the aromatic ring group and the multiple ligands are not combined with each other to form a ring, and it is confirmed that such a stable structure leads to improved lifespan and low driving voltage characteristics.

[0201] As an example, the organic metal complex according to the embodiment of the present disclosure has a structure in which an amine known to have high electron-donating ability is used as a linker instead of the conventionally used carbazole, and such a structure can lead to an enhanced combination between the metal and the ligand, thereby improving the life span and reducing the driving voltage. In addition, the organic electroluminescent device according to the embodiment including the compound according to the embodiment in the light-emitting layer can have higher luminous efficiency, increased life span and lower driving voltage.

[0202] As described above, the organic electroluminescent device according to the embodiment may have improved luminous efficiency and lifespan.

[0203] When the organic metal complex according to the embodiment is included in a light-emitting layer of an organic electroluminescent device, the organic metal complex may contribute to improvement of light-emitting efficiency and lifespan of the organic electroluminescent device.

[0204] While the subject matter of the present disclosure has been described with reference to specific embodiments thereof, it will be understood by those skilled in the art that various modifications and changes may be made without departing from the spirit and technical scope of the present disclosure.

[0205] Therefore, the technical scope of the present disclosure should not be limited to the contents described in the specification, but should be defined by the appended claims and their respective equivalents.

Claims

1. An organic metal complex represented by the following formula 1-3: Formula 1-3 in, In the above formula 1-3, L1 is a substituted or unsubstituted cyclic C2-10 heteroaryl group, wherein the heteroatom forming the ring of the heteroaryl group contains at least one nitrogen atom; Wherein, in the above formula 1-3, R1 is a C1-10 alkyl group; Wherein, in the above formula 1-3, R2, R3 and R4 are each independently a hydrogen atom, a deuterium atom, a halogen atom, a substituted or unsubstituted cyclic C6-10 aryl group, a substituted or unsubstituted cyclic C2-15 heteroaryl group, a substituted or unsubstituted C1-10 alkyl group or a cyano group; Wherein, in the above formula 1-3, R5 is a hydrogen atom, a deuterium atom, a halogen atom, a substituted or unsubstituted cyclic C6-10 aryl group, a substituted or unsubstituted cyclic C2-15 heteroaryl group, a substituted or unsubstituted C1-10 alkyl group, a substituted or unsubstituted amino group, a hydroxyl group, a thiol group or a cyano group, and in the case of a plurality of R5, the plurality of R5 are not bonded to each other or bonded to each other to form a ring; Wherein, in the above formula 1-3, n1 to n4 are each independently an integer from 0 to 3; Wherein, in the above formula 1-3, n5 is an integer from 0 to 5; Wherein, in the above formula 1-3, A1 is *-O-* or *-S-*, Wherein, the "substituted" refers to substitution by one or more than one substituent selected from the group consisting of a deuterium atom, a halogen atom, a cyano group and a C1-10 alkyl group, The organic metal complex represented by Formula 1-3 does not include the following compounds:

2. The organic metal complex according to claim 1, wherein the organic metal complex is one of the following compounds:

3. An organic electroluminescent device comprising: a first electrode; a second electrode facing the first electrode; as well as a plurality of organic layers between the first electrode and the second electrode; At least one of the plurality of organic layers comprises the organic metal complex according to claim 1 or 2.

4. The organic electroluminescent device according to claim 3, wherein: The plurality of organic layers include a hole transport region, a light emitting layer, and an electron transport region; and The organic metal complex is contained in the light emitting layer.

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