Organic light-emitting materials containing novel ancillary ligands

Abstract

There is a need to provide methods for more effective control of emission wavelength and for improving the quantum efficiency of materials. [Solution] The present invention is realized by providing metal complexes and discloses organic light-emitting materials containing novel ancillary ligands, using a series of novel structural acetylacetone-type ancillary ligands. Metal complexes containing novel ancillary ligands can be used as light-emitting materials in the light-emitting layer of organic electroluminescent devices. These novel ligands can modify the sublimation characteristics, improve quantum efficiency, and improve device performance. The present invention further discloses electroluminescent devices and compound formulations.

Description

[Technical Field]

[0001] The present invention relates to compounds for use in organic electronic devices, such as organic light emitting devices, and in particular to metal complexes containing novel ancillary ligands, electroluminescent devices and compound formulations containing such metal complexes. [Background technology]

[0002] Organic electronic devices include, but are not limited to, organic light-emitting diodes (OLEDs), organic field-effect transistors (O-FETs), organic light-emitting transistors (OLETs), organic photovoltaic cells (OPVs), dye-sensitized solar cells (DSSCs), organic photodetectors, organic photosensitive devices, organic field-effect devices (OFQDs), light-emitting electrochemical cells (LECs), organic laser diodes, and organic plasma light-emitting devices.

[0003] In 1987, Tang and Van Slyke of Eastman Kodak reported a bilayer organic electroluminescent device containing an arylamine hole-transporting layer and a tris-8-hydroxyquinoline-aluminum layer as the electron-transporting and emissive layers (Applied Physics Letters, 1987, 51(12):913-915). Once a bias is applied to the device, green light is emitted from the device. This invention laid the foundation for the development of modern organic light-emitting diodes (OLEDs). The most advanced OLEDs may contain multiple layers, such as charge injection and transport layers, charge and exciton blocking layers, and one or more emissive layers between the cathode and anode. Being self-emissive solid-state devices, OLEDs offer tremendous potential for display and lighting applications. Furthermore, the inherent properties of organic materials, such as their flexibility, make them highly suitable for specialized applications, such as fabrication on flexible substrates.

[0004] OLEDs are divided into three different types depending on their emission mechanism. The OLED invented by Tang and van Slyke is a fluorescent OLED, which uses only singlet emission. Triplets generated in the device are wasted through non-radiative decay pathways, and the internal quantum efficiency (IQE) of fluorescent OLEDs is only 25%, a limitation that has hindered the commercialization of OLEDs. In 1997, Forrest and Thompson reported on phosphorescent OLEDs that use triplet emission from heavy metal-containing complexes as the emitter. Therefore, singlet and triplet emissions can be harvested, achieving an IQE of 100%. Due to their high efficiency, the discovery and development of phosphorescent OLEDs directly contributes to the commercialization of active matrix OLEDs (AMOLEDs). Recently, Adachi has achieved high efficiency through thermally activated delayed fluorescence (TADF) of organic compounds. These emitters have a small singlet-triplet gap, allowing excitons to transition from triplet to singlet. In TADF devices, the high IQE is due to triplet excitons threading between reverse systems (reverse intersystem crossing) to generate singlet excitons.

[0005] OLEDs can be further divided into small molecule and polymer OLEDs depending on the form of the material used. Small molecules refer to non-polymeric organic or organometallic materials, and as long as they have a well-defined structure, the molecular weight of the small molecule can be large. Dendrimers, which have a well-defined structure, are considered small molecules. Polymer OLEDs include conjugated polymers and non-conjugated polymers with side-chain emissive groups. Post-polymerization during the manufacturing process can turn small molecule OLEDs into polymer OLEDs.

[0006] Various methods for manufacturing OLEDs are known. Small molecule OLEDs are generally manufactured by vacuum thermal evaporation. Polymer OLEDs are manufactured by solution processes, such as spin coating, inkjet printing, and nozzle printing. If the material can be dissolved or dispersed in a solvent, small molecule OLEDs can also be manufactured by solution processes. [Prior art documents] [Patent documents]

[0007] [Patent Document 1] U.S. Patent No. 7,279,704 [Patent Document 2] U.S. Patent No. 5,844,363 [Patent Document 3] US Patent Application Publication No. 2003 / 0230980 [Patent Document 4] U.S. Patent No. 6,303,238 [Patent Document 5] U.S. Patent No. 5,703,436 [Patent Document 6] U.S. Patent No. 5,707,745 [Patent Document 7] U.S. Patent No. 6,097,147 [Patent Document 8] US Patent Application Publication No. 2004 / 0174116 [Patent Document 9] U.S. Patent No. 7,968,146 [Patent Document 10] U.S. Patent Application No. 2016 / 0359122 [Patent Document 11] U.S. Patent Application No. 2015 / 0349273 [Non-patent literature]

[0008] [Non-Patent Document 1] Applied Physics Letters, 1987, 51(12):913-915 Summary of the Invention [Problem to be solved by the invention]

[0009] The emission color of an OLED can be achieved by the structural design of the emissive material. An OLED may contain one or more emissive layers to achieve a desired spectrum. While phosphorescent materials have already been successfully commercialized in green, yellow, and red OLEDs, blue phosphorescent devices still suffer from problems such as unsaturated blue, short service life, and high operating voltage. Commercially available full-color OLED displays generally use a mixed strategy, employing blue fluorescence and yellow, red, or green phosphorescence. Currently, phosphorescent OLEDs suffer from a rapid decrease in efficiency at high brightness. Furthermore, there is a demand for more saturated emission spectra, higher efficiency, and longer device service life.

[0010] The auxiliary ligands of phosphorescent materials can be used to fine-tune the emission wavelength, improve the sublimation properties, and improve the efficiency of the materials. Conventional auxiliary ligands, such as acetylacetonide-type ligands, especially acetylacetonide-type ligands containing alkyl branched chains, have achieved some effects in controlling the properties mentioned above, but in order to meet increasingly higher performance requirements, their performance needs to be further improved, and in particular, methods for more effectively controlling the emission wavelength and improving the quantum efficiency of materials need to be provided. [Means for solving the problem]

[0011] The present invention provides an ancillary ligand with a novel structure, which can more effectively improve the sublimation property and increase the quantum efficiency compared to previously reported ancillary ligands.

[0012] The present invention aims to solve at least some of the above problems by providing a series of novel structural ancillary ligands of the acetylacetonide class. These ligands can be attached to metal complexes and used as emissive materials in the emissive layer of electroluminescent devices. These novel ligands can modify the sublimation properties, improve quantum efficiency, and enhance device performance.

[0013] According to one embodiment of the present invention, the ligand L of formula 1 a Disclosed is a metal complex comprising: [ka] (R1 to R7 each independently represent hydrogen, deuterium, a halogen, a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms, a substituted or unsubstituted cycloalkyl group having 3 to 20 ring carbon atoms, a substituted or unsubstituted heteroalkyl group having 1 to 20 carbon atoms, a substituted or unsubstituted aralkyl group having 7 to 30 carbon atoms, a substituted or unsubstituted alkoxy group having 1 to 20 carbon atoms, a substituted or unsubstituted aryloxy group having 6 to 30 carbon atoms, a substituted or unsubstituted alkenyl group having 2 to 20 carbon atoms, a substituted or unsubstituted aryloxy group having 6 to 3 ... a substituted or unsubstituted aryl group having 6 to 30 carbon atoms, a substituted or unsubstituted heteroaryl group having 3 to 30 carbon atoms, a substituted or unsubstituted alkylsilyl group having 3 to 20 carbon atoms, a substituted or unsubstituted arylsilyl group having 6 to 20 carbon atoms, a substituted or unsubstituted amine group, acyl group, carbonyl group, carboxyl group, ester group, nitrile group, isonitrile group, thiol group, sulfinyl group, sulfonyl group, phosphine group, and a combination thereof; two adjacent substituents may be linked to form a ring or a fused structure; At least one of the groups consisting of R1, R2, and R3 and the group consisting of R4, R5, and R6 contains three identical or different substituents; the three identical or different substituents each contain at least one carbon atom; Of the three identical or different substituents, at least one substituent contains at least two carbon atoms.

[0014] According to another embodiment of the present invention, there is further disclosed an electroluminescent device, comprising an anode, a cathode, and an organic layer disposed between the anode and the cathode, wherein the organic layer comprises a ligand L represented by Formula 1: a The present invention also includes metal complexes comprising: [ka] (R1 to R7 each independently represent hydrogen, deuterium, a halogen, a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms, a substituted or unsubstituted cycloalkyl group having 3 to 20 ring carbon atoms, a substituted or unsubstituted heteroalkyl group having 1 to 20 carbon atoms, a substituted or unsubstituted aralkyl group having 7 to 30 carbon atoms, a substituted or unsubstituted alkoxy group having 1 to 20 carbon atoms, a substituted or unsubstituted aryloxy group having 6 to 30 carbon atoms, a substituted or unsubstituted alkenyl group having 2 to 20 carbon atoms, a substituted or unsubstituted aryloxy group having 6 to 3 ... a substituted or unsubstituted aryl group having 6 to 30 carbon atoms, a substituted or unsubstituted heteroaryl group having 3 to 30 carbon atoms, a substituted or unsubstituted alkylsilyl group having 3 to 20 carbon atoms, a substituted or unsubstituted arylsilyl group having 6 to 20 carbon atoms, a substituted or unsubstituted amine group, acyl group, carbonyl group, carboxyl group, ester group, nitrile group, isonitrile group, thiol group, sulfinyl group, sulfonyl group, phosphine group, and a combination thereof; two adjacent substituents may be linked to form a ring or a fused structure; At least one of the groups consisting of R1, R2, and R3 and the group consisting of R4, R5, and R6 contains three identical or different substituents; the three identical or different substituents each contain at least one carbon atom; Of the three identical or different substituents, at least one substituent contains at least two carbon atoms.

[0015] According to another embodiment of the present invention, the ligand L of formula 1 a Further disclosed are formulations of compounds, including metal complexes comprising:

[0016] Metal complexes containing the novel ancillary ligands disclosed in this invention can be used as emitting materials in the light-emitting layer of organic electroluminescent devices. These novel ligands can modify the sublimation properties of the emitting materials, improve the quantum efficiency, and enhance the device performance. [Brief explanation of the drawings]

[0017] [Figure 1] 1 is a schematic diagram of an organic light-emitting device that may include a ligand, metal complex or compound formulation according to the present invention. [Figure 2] 1 is a schematic diagram of another organic light-emitting device that may include a ligand, metal complex or compound formulation according to the present invention. [Figure 3] FIG. 1 shows structural formula 1 of the ligand compound La according to the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0018] OLEDs can be fabricated on a variety of substrates, including glass, plastic, and metal. FIG. 1 illustrates, by way of example and not limitation, an organic light-emitting device 100. The drawings are not necessarily drawn to scale, and some layer structures may be omitted, if necessary. Device 100 may include a substrate 101, an anode 110, a hole-injection layer 120, a hole-transport layer 130, an electron-blocking layer 140, an emissive layer 150, a hole-blocking layer 160, an electron-transport layer 170, an electron-injection layer 180, and a cathode 190. Device 100 may be fabricated by depositing the layers described, in order. The properties, functions, and exemplary materials of each layer are described in more detail in U.S. Pat. No. 7,279,704, columns 6-10, the entire contents of which are incorporated herein by reference.

[0019] There are many examples of each of these layers. For example, U.S. Patent No. 5,844,363 (Patent Document 2), incorporated herein by reference in its entirety, discloses a flexible and transparent substrate-anode combination. For example, U.S. Patent Application Publication No. 2003 / 0230980 (Patent Document 3), incorporated herein by reference in its entirety, discloses that an example of a p-type doped hole transport layer is m-MTDATA doped with F4-TCNQ at a molar ratio of 50:1. Examples of host materials are disclosed in U.S. Patent Application Publication No. 6,303,238 (Patent Document 4) by Thompson et al., incorporated herein by reference in its entirety. For example, U.S. Patent Application Publication No. 2003 / 0230980 (Patent Document 3), incorporated herein by reference in its entirety, discloses that an example of an n-type doped electron transport layer is BPhen doped with Li at a molar ratio of 1:1. U.S. Patent Nos. 5,703,436 and 5,707,745, incorporated herein by reference in their entireties, disclose examples of cathodes, including composite cathodes having a thin metal layer, such as Mg:Ag, coated thereon with a sputter-deposited transparent conductive ITO layer. U.S. Patent No. 6,097,147 and U.S. Patent Application Publication No. 2003 / 0230980, incorporated herein by reference in their entireties, describe the principles and use of blocking layers in more detail. U.S. Patent Application Publication No. 2004 / 0174116, incorporated herein by reference in its entirety, provides examples of injection layers. U.S. Patent Application Publication No. 2004 / 0174116, incorporated herein by reference in its entirety, describes protective layers.

[0020] The above-described split-layer structures are provided by way of non-limiting examples. OLED functions can be achieved by combining the various layers described above, or some layers can be omitted entirely. It may also include other layers not explicitly described. Within each layer, a single material or a mixture of multiple materials can be used to achieve optimal performance. Any functional layer may also include multiple sublayers; for example, an emissive layer may have two layers of different emissive materials to achieve a desired emission spectrum.

[0021] In one embodiment, an OLED may be described as having an "organic layer" disposed between a cathode and an anode. The organic layer may include one or more layers.

[0022] An OLED also requires an encapsulation layer, and as shown in FIG. 2, an organic light-emitting device 200 is shown by way of example and not limitation. Unlike FIG. 1, an encapsulation layer 102 may be included on the cathode 190 to protect against harmful substances such as moisture and oxygen from the outside. Any material capable of providing an encapsulation function, such as glass or an organic-inorganic hybrid layer, may be used as the encapsulation layer. The encapsulation layer should be disposed directly or indirectly on the exterior of the OLED device. Multilayer thin-film encapsulation is described in U.S. Pat. No. 7,968,146, the entire contents of which are incorporated herein by reference.

[0023] Devices manufactured according to embodiments of the present invention may be incorporated into a variety of consumer products having one or more electronic modules (or units) of the device, including, for example, flat panel displays, monitors, medical monitors, televisions, billboards, indoor or outdoor lighting and / or signal lamps, head-up displays, fully or partially transparent displays, flexible displays, smartphones, flat panel computers, flat panel mobile phones, wearable devices, smart watches, laptop computers, digital cameras, portable video cameras, viewfinders, microdisplays, 3-D displays, automotive displays, and tail lights.

[0024] The materials and structures described herein may also be used in the other organic electronic devices listed above.

[0025] "Top" means furthest from the substrate and "bottom" means closest to the substrate. When a first layer is described as being "on" a second layer, the first layer is disposed relatively far from the substrate. Other layers may be present between the first and second layers, unless the first layer is specified as being "in contact with" the second layer. Illustratively, the cathode may still be described as being "on" the anode, even if various organic layers are present between the cathode and anode.

[0026] "Solution processable" means capable of being dissolved, dispersed or transported in and / or deposited from a liquid medium in the form of a solution or suspension.

[0027] It is believed that if a ligand directly enhances the photosensitizing properties of the emitting material, it may be referred to as "photosensitizing." If a ligand does not enhance the photosensitizing properties of the emitting material, it may be referred to as "auxiliary." However, it is believed that the auxiliary ligand can modify the properties of the photosensitizing ligand.

[0028] It is believed that the internal quantum efficiency (IQE) of fluorescent OLEDs may exceed the 25% spin-statistics limit due to the presence of delayed fluorescence. Delayed fluorescence may be generally divided into two types: P-type delayed fluorescence and E-type delayed fluorescence. P-type delayed fluorescence is generated by triplet-triplet annihilation (TTA).

[0029] On the other hand, E-type delayed fluorescence relies on the conversion of triplet and singlet excited states rather than the collision of two triplets. Compounds capable of generating E-type delayed fluorescence must have an extremely small singlet-triplet gap to allow for the energy state conversion. Thermal energy can activate the triplet-to-singlet transition. This type of delayed fluorescence is also called thermally activated delayed fluorescence (TADF). A notable feature of TADF is that the delayed component increases with increasing temperature. If the rate of threading between reverse intersystems (RISC) is sufficiently fast, the non-radiative decay from the triplet can be minimized, and the proportion of backfilled singlet excited states can reach 75%. The total proportion of singlets can be 100%, far exceeding the 25% spin statistics of the exciton due to electrochemical reactions.

[0030] The characteristics of E-type delayed fluorescence can be seen from an excited complex system or a single compound. Without being limited by theory, E-type delayed fluorescence is observed when the emissive material has a small singlet-triplet energy gap (ΔE S-T ) is required. Organic non-metal-containing donor-acceptor emissive materials have the potential to achieve this. The emission of these materials is typically characterized as donor-acceptor charge transition (CT) emission. In these donor-acceptor compounds, the spatial separation between the HOMO and LUMO is generally small, ΔE S-T These states may include CT states. Donor-acceptor emissive materials are typically constructed by combining an electron donor moiety (e.g., an amine group or a carbazole derivative) with an electron acceptor moiety (e.g., an N-containing six-membered aromatic ring).

[0031] The definitions of technical terms relating to substituents are explained below.

[0032] Halogen or halide, as used herein, includes fluorine, chloro, bromine and iodine.

[0033] The alkyl group includes straight-chain and branched-chain alkyl groups. Specific examples of alkyl groups include methyl, ethyl, propyl, isopropyl, n-butyl, sec-butyl, isobutyl, tert-butyl, n-pentyl, n-hexyl, n-heptyl, n-octyl, n-nonyl, n-decyl, n-undecyl, n-dodecyl, n-tridecyl, n-tetradecyl, n-pentadecyl, n-hexadecyl, n-heptadecyl, n-octadecyl, neopentyl, 1-methylpentyl, 2-methylpentyl, 1-pentylhexyl, 1-butylpentyl, 1-heptyloctyl, and 3-methylpentyl groups. The alkyl group may also be substituted. Carbon atoms in the alkyl group chain may be replaced with other heteroatoms. Among these, methylethyl, propyl, isopropyl, n-butyl, sec-butyl, isobutyl, tert-butyl, n-pentyl, and neopentyl are preferred.

[0034] As used herein, the term "cycloalkyl group" includes cyclic alkyl groups. Preferred cycloalkyl groups are those having 4 to 10 ring carbon atoms, including cyclobutyl, cyclopentyl, cyclohexyl, 4-methylcyclohexyl, 4,4-dimethylcyclohexyl, 1-adamantyl, 2-adamantyl, 1-norbornyl, and 2-norbornyl. The cycloalkyl group may be substituted. The carbon atoms in the ring may be substituted with other heteroatoms.

[0035] As used herein, the term "alkenyl group" includes straight-chain and branched-chain olefinic groups. Preferred alkenyl groups are those having 2 to 15 carbon atoms. Examples of alkenyl groups include vinyl, allyl, 1-butenyl, 2-butenyl, 3-butenyl, 1,3-butadienyl, 1-methylvinyl, styryl, 2,2-diphenylvinyl, 1,2-diphenylvinyl, 1-methylallyl, 1,1-dimethylallyl, 2-methylallyl, 1-phenylallyl, 2-phenylallyl, 3-phenylallyl, 3,3-diphenylallyl, 1,2-dimethylallyl, 1-phenyl-1-butenyl, and 3-phenyl-1-butenyl. The alkenyl group may also be substituted.

[0036] As used herein, the term "alkynyl group" includes straight-chain and branched-chain alkynyl groups. Preferred alkynyl groups are those having 2 to 15 carbon atoms. The alkynyl group may be substituted.

[0037] As used herein, aryl or aromatic groups encompass both non-fused and fused systems. Preferred aryl groups are those having 6 to 60 carbon atoms, more preferably 6 to 20 carbon atoms, and even more preferably 6 to 12 carbon atoms. Examples of aryl groups include phenyl, biphenyl, terphenyl, triphenylene, tetraphenylene, naphthalene, anthracene, phenalene, phenanthrene, fluorene, pyrene, chrysene, perylene, and azulene, with phenyl, biphenyl, terphenyl, triphenylene, fluorenyl, and naphthalene being preferred. The aryl group may also be substituted. Examples of non-fused aryl groups include phenyl, biphenyl-2-yl, biphenyl-3-yl, biphenyl-4-yl, p-terphenyl-4-yl, p-terphenyl-3-yl, p-tribiphenyl-2-yl, m-terphenyl-4-yl, m-terphenyl-3-yl, m-terphenyl-2-yl, o-tolyl, m-tolyl, p-tolyl, p-(2-phenylpropyl)phenyl, 4'-methylbiphenyl, 4''-tert-butyl-p-terphenyl-4-yl, o-cumyl, m-cumyl, p-cumyl, 2,3-xylyl, 3,4-xylyl, 2,5-dimethylphenyl, mesitylene, and m-tetraphenyl.

[0038] As used herein, heterocyclic groups or heterocycles contemplate aromatic and non-aromatic cyclic groups. Isoaryl groups are also referred to as heteroaryl groups. Preferred non-aromatic heterocyclic groups have 3 to 7 ring atoms and contain at least one heteroatom, such as nitrogen, oxygen, or sulfur. The heterocyclic group may also be an aromatic heterocyclic group having at least one heteroatom selected from nitrogen, oxygen, sulfur, and selenium.

[0039] Heteroaryl groups, as used herein, contemplate both non-fused and fused heteroaromatic groups containing 1 to 5 heteroatoms. Preferred heteroaryl groups are those containing 3 to 30 carbon atoms, more preferably 3 to 20 carbon atoms, and even more preferably 3 to 12 carbon atoms. Suitable heteroaryl groups include dibenzothiophene, dibenzofuran, dibenzoselenophene, furan, thiophene, benzofuran, benzothiophene, benzoselenophene, carbazole, indolocarbazole, pyridoindole, pyrrolopyridine, pyrazole, imidazole, triazole, oxazole, thiazole, oxadiazole, oxatriazole, dioxazole, thiadiazole, pyridine, pyridazine, pyrimidine, pyrazine, triazine, oxazine, oxathiazine, oxadiazine, indole, benzimidazole, indazole, indenoazine, benzoxazole, and benzisoxazole. , benzothiazole, quinoline, isoquinoline, cinnoline, quinazoline, quinoxaline, naphthyridine, phthalazine, pteridine, xanthene, acridine, phenazine, phenothiazine, benzofuranpyridine, furodipyridine, benzothienopyridine, thienobipyridine, benzoselenopyridine, and selenobenzopyridine, and preferably includes dibenzothiophene, dibenzofuran, dibenzoselenophene, carbazole, indolocarbazole, imidazole, pyridine, triazine, benzimidazole, 1,2-azaborane, 1,3-azaborane, 1,4-azaborane, borazole, and their aza analogs. Heteroaryl groups may also be substituted.

[0040] The alkoxy group is represented by an -O-alkyl group. Examples and preferred examples of the alkyl group are the same as those mentioned above. Examples of the alkoxy group having 1 to 20 carbon atoms, preferably 1 to 6 carbon atoms, include methoxy, ethoxy, propoxy, butoxy, pentyloxy, and hexyloxy. An alkoxy group having 3 or more carbon atoms may be linear, cyclic, or branched.

[0041] The aryloxy group is represented by an —O-aryl group or an —O-heteroaryl group. Examples and preferred examples of the aryl group and heteroaryl group are the same as those mentioned above. Examples of the aryloxy group having 6 to 40 carbon atoms include a phenoxy group and a biphenyloxy group.

[0042] As used herein, an aralkyl group is an alkyl group having an aryl substituent. Aralkyl groups may also be substituted. Examples of aralkyl groups include benzyl, 1-phenylethyl, 2-phenylethyl, 1-phenylisopropyl, 2-phenylisopropyl, phenyl-tert-butyl, α-naphthylmethyl, 1-α-naphthylethyl, 2-α-naphthylethyl, 1-α-naphthylisopropyl, 2-α-naphthylisopropyl, β-naphthylmethyl, 1-β-naphthyl-ethyl, 2-β-naphthyl-ethyl, 1-β-naphthylisopropyl, 2-β-naphthylisopropyl, p-methylbenzyl, m-methylbenzyl, o-methylbenzyl, p-chlorobenzyl, m-chlorobenzyl, and m-chlorobenzyl. Examples of benzyl include chlorobenzyl, o-chlorobenzyl, p-bromobenzyl, m-bromobenzyl, o-bromobenzyl, p-iodobenzyl, m-iodobenzyl, o-iodobenzyl, p-hydroxybenzyl, m-hydroxybenzyl, o-hydroxybenzyl, p-aminobenzyl, m-aminobenzyl, o-aminobenzyl, p-nitrobenzyl, m-nitrobenzyl, o-nitrobenzyl, p-cyanobenzyl, m-cyanobenzyl, o-cyanobenzyl, 1-hydroxy-2-phenylisopropyl, and 1-chloro-2-phenylisopropyl, of which benzyl, p-cyanobenzyl, m-cyanobenzyl, o-cyanobenzyl, 1-phenylethyl, 2-phenylethyl, 1-phenylisopropyl, and 2-phenylisopropyl are preferred.

[0043] The "aza" in azadibenzofuran, aza-dibenzothiophene, etc., refers to the replacement of one or more C—H groups in the corresponding aromatic fragment with a nitrogen atom. For example, azatriphenylene includes dibenzo[f,h]quinoxaline, dibenzo[f,h]quinoline, and other analogs having two or more nitrogens in the ring system. Those skilled in the art can readily envision other nitrogen analogs of the above-mentioned aza derivatives, and all of these analogs are defined as being included within the terminology described herein.

[0044] The alkyl group, cycloalkyl group, alkenyl group, alkynyl group, aralkyl group, heterocyclic group, aryl group, and heteroaryl group may be unsubstituted or may be substituted with one or more groups selected from deuterium, halogen, alkyl group, cycloalkyl group, aralkyl group, alkoxy group, aryloxy group, amino group, cyclic amino group, silyl group, alkenyl group, cycloalkenyl group, heteroalkenyl group, alkynyl group, aryl group, heteroaryl group, acyl group, carbonyl group, carboxyl group, ether group, ester group, nitrile group, isonitrile group, thioalkyl group, sulfinyl group, sulfonyl group, phosphine group, and combinations thereof.

[0045] When describing a molecular fragment as being attached to another moiety by a substituent or otherwise, it should be understood that the designation can be defined as either the fragment (e.g., phenyl, phenylene, naphthyl, dibenzofuranyl) or the entire molecule (e.g., benzene, naphthalene, dibenzofuran). As used herein, the designations of the substituents or different modes of attachment of the fragment are considered equivalent.

[0046] In the compounds described herein, hydrogen atoms may be partially or completely replaced with deuterium.Other atoms, such as carbon and nitrogen, may also be replaced with other stable isotopes thereof.In order to improve the efficiency and stability of the device, it may be preferable to replace other stable isotopes in the compound.

[0047] In the compounds referred to herein, multiple substitution refers to a range up to the most available substitution, including double substitution. When a substituent in a compound referred to herein is referred to as multiple substitution (including double substitution, triple substitution, quadruple substitution, etc.), it means that the substituent may be present at multiple available substitution positions on the bond structure, and the substituents present at all available substitution positions may be the same structure or different structures.

[0048] In the compounds referred to herein, when two adjacent substituents are optionally joined to form a ring, this is understood to refer to the two groups being linked to each other by a chemical bond, as illustrated by the following diagram: [ka]

[0049] Furthermore, the statement that two adjacent substituents may be bonded to form a ring is understood to mean that when one of the two groups represents hydrogen, the second group is bonded to the position where the hydrogen atom is bonded to form a ring. This is exemplified by the following diagram: [ka]

[0050] According to one embodiment of the present invention, the ligand L of formula 1 a A metal complex comprising: [ka] R1 to R7 each independently represent hydrogen, deuterium, halogen, a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms, a substituted or unsubstituted cycloalkyl group having 3 to 20 ring carbon atoms, a substituted or unsubstituted heteroalkyl group having 1 to 20 carbon atoms, a substituted or unsubstituted aralkyl group having 7 to 30 carbon atoms, a substituted or unsubstituted alkoxy group having 1 to 20 carbon atoms, a substituted or unsubstituted aryloxy group having 6 to 30 carbon atoms, a substituted or unsubstituted alkenyl group having 2 to 20 carbon atoms, a substituted or unsubstituted aryl group having 6 to 30 carbon atoms, a substituted or unsubstituted heteroaryl group having 3 to 30 carbon atoms, a substituted or unsubstituted alkylsilyl group having 3 to 20 carbon atoms, or a substituted or unsubstituted arylsilyl group having 6 to 20 carbon atoms. group), a substituted or unsubstituted amine group having 0 to 20 carbon atoms, an acyl group, a carbonyl group, a carboxyl group, an ester group, a nitrile group, an isonitrile group, a thiol group, a sulfinyl group, a sulfonyl group, a phosphine group, and a combination thereof; two adjacent substituents may be linked to form a ring or a fused structure; At least one of the groups consisting of R1, R2, and R3 and the group consisting of R4, R5, and R6 contains three identical or different substituents; the three identical or different substituents each contain at least one carbon atom; Of the three identical or different substituents, at least one substituent contains at least two carbon atoms.

[0051] In the examples, the statement "two adjacent substituents may be bonded to form a ring" refers to the fact that two adjacent substituents in Formula 1, such as substituents R1 and R2, substituents R1 and R3, substituents R2 and R3, substituents R4 and R5, substituents R4 and R6, or substituents R5 and R6, may be bonded to each other by a chemical bond. It should be noted that this statement does not include cases where three adjacent substituents, such as substituents R1, R2, and R3, or substituents R4, R5, and R6, are bonded to form a ring. This statement does not include cases where any one of the substituents R1 to R6 is bonded to the substituent R7 to form a ring. In some cases, the ring formed by bonding in this statement does not include a bridged ring. It is also obvious to those skilled in the art that the substituents R1 to R7 in Formula 1 do not necessarily have to be bonded to each other.

[0052] In this embodiment, R1, R2, and R3 constitute Group A, and R4, R5, and R6 constitute Group B, and the three substituents in at least one of Groups A and B may be the same or different. The three different substituents mentioned here include the case where only two of the substituents are the same. For Groups A and B, at least one of the three substituents satisfies the condition that, regardless of whether the three substituents in said one group are the same or different, each of them contains at least one carbon atom, and at least one of the three substituents contains at least two carbon atoms.

[0053] According to another embodiment of the present invention, the metal in the metal complex is selected from the group consisting of Cu, Ag, Au, Ru, Rh, Pd, Pt, Os and Ir.

[0054] According to another embodiment of the present invention, the metal in the metal complex is selected from Pt or Ir.

[0055] According to another embodiment of the present invention, in Formula 1, R1 to R7 are each independently selected from the group consisting of hydrogen, deuterium, fluorine, a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms, a substituted or unsubstituted cycloalkyl group having 3 to 20 ring carbon atoms, a substituted or unsubstituted heteroalkyl group having 1 to 20 carbon atoms, and combinations thereof.

[0056] According to another embodiment of the present invention, in Formula 1, R1 to R7 are each independently selected from the group consisting of hydrogen, methyl, ethyl, isopropyl, isobutyl, neopentyl, cyclobutyl, cyclopentyl, cyclohexyl, 4,4-dimethylcyclohexyl, norbornyl, adamantyl, fluorine, trifluoromethyl, 2,2,2-trifluoroethyl, 3,3,3-trifluoropropyl, 3,3,3-trifluoro-2,2-dimethylpropyl, and deuterated versions of the above groups.

[0057] According to another embodiment of the invention, the complex has the general formula M(L a ) m (L b ) n (L c ) q of which, L b and L c are the secondary and tertiary ligands that coordinate with M, and L b and L c may be the same or different, L a , L b and L c may be linked to form a multidentate ligand; m is 1, 2 or 3, n is 0, 1 or 2, q is 0, 1 or 2, and m+n+q is the oxidation state of M; L b and L c are each independently [ka] selected from the group consisting of R a , Rb , and R c may represent mono-, di-, tri-, tetra- or unsubstituted; X b are O, S, Se, and NR N1 , and C.R. C1 R C2 selected from the group consisting of R a , R b , R c , R N1 , R C1 and R C2 are each independently hydrogen, deuterium, halogen, a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms, a substituted or unsubstituted cycloalkyl group having 3 to 20 ring carbon atoms, a substituted or unsubstituted heteroalkyl group having 1 to 20 carbon atoms, a substituted or unsubstituted aralkyl group having 7 to 30 carbon atoms, a substituted or unsubstituted alkoxy group having 1 to 20 carbon atoms, a substituted or unsubstituted aryloxy group having 6 to 30 carbon atoms, a substituted or unsubstituted alkenyl group having 2 to 20 carbon atoms, a substituted or unsubstituted selected from the group consisting of substituted aryl groups having 6 to 30 carbon atoms, substituted or unsubstituted heteroaryl groups having 3 to 30 carbon atoms, substituted or unsubstituted alkylsilyl groups having 3 to 20 carbon atoms, substituted or unsubstituted arylsilyl groups having 6 to 20 carbon atoms, substituted or unsubstituted amine groups, acyl groups, carbonyl groups, carboxyl groups, ester groups, nitrile groups, isonitrile groups, thiol groups, sulfinyl groups, sulfonyl groups, phosphine groups, and combinations thereof, Two adjacent substituents may be bonded to form a ring.

[0058] In this example, L a , L b and L c may be linked to form multidentate, e.g., tetradentate, ligands. a , L b and L c It is obvious that the groups do not have to be bonded to form a multidentate ligand.

[0059] In this example, the ligand Lb and L c In the structure represented by the formula: two adjacent substituents may be bonded to form a ring, a , R b , R c , R N1 , R c1 and R c2 For substituents with different numbers, two adjacent substituents may be bonded to form a ring, and R a , R b , and R c indicates di-, tri- or tetra-substitution, R a , R b , and R c and when two or more substituents having the same number are present in the ligand L, two adjacent substituents may be bonded to form a ring. b and L c In some cases, none of the substituents in the structure represented by the formula may be bonded to each other.

[0060] According to another embodiment of the invention, the complex has the general formula Ir(L a )(L b )2.

[0061] According to another embodiment of the present invention, in formula 1, the ligand L a is selected from the group consisting of compounds of the following structure: [ka] [ka] [ka] [ka] [ka] [ka] [ka] [ka] [ka] [ka] [ka] [ka]

[0062] According to one embodiment of the present invention, the ligand L b is selected from the group consisting of compounds of the following structure: [ka] [ka] [ka] [ka] [ka] [ka] [ka]

[0063] According to one embodiment of the present invention, in the metal complex, L a and / or L b may be partially or fully deuterated.

[0064] According to one embodiment of the present invention, the metal complex has the general formula Ir(La )(L b )2, and L a L a1 ~L a280 and L b L b1 ~L b201 Any one of the above or a combination of any two of the above.

[0065] According to one embodiment of the present invention, there is further disclosed an electroluminescent device, including an anode, a cathode, and an organic layer disposed between the anode and the cathode, wherein the organic layer comprises a ligand L represented by Formula 1: a The present invention also includes metal complexes comprising: [ka] R1 to R7 each independently represent hydrogen, deuterium, a halogen, a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms, a substituted or unsubstituted cycloalkyl group having 3 to 20 ring carbon atoms, a substituted or unsubstituted heteroalkyl group having 1 to 20 carbon atoms, a substituted or unsubstituted aralkyl group having 7 to 30 carbon atoms, a substituted or unsubstituted alkoxy group having 1 to 20 carbon atoms, a substituted or unsubstituted aryloxy group having 6 to 30 carbon atoms, a substituted or unsubstituted alkenyl group having 2 to 20 carbon atoms, a substituted or unsubstituted aryloxy group having 6 to 3 ... is selected from the group consisting of unsubstituted aryl groups having 6 to 30 carbon atoms, substituted or unsubstituted heteroaryl groups having 3 to 30 carbon atoms, substituted or unsubstituted alkylsilyl groups having 3 to 20 carbon atoms, substituted or unsubstituted arylsilyl groups having 6 to 20 carbon atoms, substituted or unsubstituted amine groups, acyl groups, carbonyl groups, carboxyl groups, ester groups, nitrile groups, isonitrile groups, thiol groups, sulfinyl groups, sulfonyl groups, phosphine groups, and combinations thereof, each having 0 to 20 carbon atoms; two adjacent substituents may be linked to form a ring or a fused structure; At least one of the groups consisting of R1, R2, and R3 and the group consisting of R4, R5, and R6 contains three identical or different substituents; the three identical or different substituents each contain at least one carbon atom; Of the three identical or different substituents, at least one substituent contains at least two carbon atoms.

[0066] According to one embodiment of the present invention, in the device, the organic layer is a light-emitting layer, and the metal complex is a light-emitting material.

[0067] According to one embodiment of the present invention, the element emits red light.

[0068] According to one embodiment of the present invention, the element emits white light.

[0069] According to one embodiment of the present invention, the organic layer further comprises a host compound.

[0070] According to one embodiment of the present invention, the organic layer further comprises a host compound containing at least any one chemical group selected from the group consisting of benzene, biphenyl, pyridine, pyrimidine, triazine, carbazole, azacarbazole, indolocarbazole, dibenzothiophene, azadibenzothiophene, dibenzofuran, azadibenzofuran, dibenzoselenophene, azadibenzoselenophene, triphenylene, azatriphenylene, fluorenyl, silicon fluorene, naphthalene, quinoline, isoquinoline, quinazoline, quinoxaline, phenanthrene, azaphenanthrene, and combinations thereof.

[0071] According to another embodiment of the present invention, the ligand L of formula 1 a The specific structure of Formula 1 is as in any of the examples above.

[0072] [Combination with other materials] The materials of the specific layers used in the organic light-emitting device described in the present invention can be used in combination with various other materials present in the device. These combinations of materials are described in detail in paragraphs 0132 to 0161 of U.S. Patent Application Publication No. 2016 / 0359122 (Patent Document 10), the contents of which are incorporated herein by reference in their entirety. The materials described or referenced are non-limiting examples of materials that can be used in combination with the compounds disclosed herein, and those skilled in the art can easily refer to the literature to identify other materials that can be used in combination.

[0073] It is stated herein that the materials of specific layers used in organic light-emitting devices can be used in combination with various other materials present in the device. Illustratively, the light-emitting dopants disclosed herein can be used in combination with various hosts, transport layers, blocking layers, injection layers, electrodes, and other possible layers. These material combinations are described in detail in paragraphs 0080 to 0101 of U.S. Patent Application Publication No. 2015 / 0349273 (Patent Document 11), the contents of which are incorporated herein by reference in their entirety. The materials described or mentioned are non-limiting examples of materials that can be used in combination with the compounds disclosed herein, and those skilled in the art can easily refer to the literature to identify other materials that can be used in combination.

[0074] In the material synthesis examples, all reactions are carried out under nitrogen protection unless otherwise stated. All reaction solvents were anhydrous and used as they were commercially available. The synthesized products were subjected to structural confirmation and property testing using one or more instruments commonly used in the art (including, but not limited to, a Bruker nuclear magnetic resonance spectrometer, a Shimadzu liquid chromatograph, a liquid chromatography / mass spectrometer, a gas chromatography / mass spectrometer, and a differential scanning calorimeter, a Lengguang Technology fluorescence spectrophotometer, a Wuhan Corrtest Instruments Corp., Ltd. electrochemical workstation, and an Anhui Beike sublimation apparatus) in a manner familiar to those skilled in the art. In the device examples, the device properties were also tested using common instruments commonly used in the art (including, but not limited to, an Angstrom Engineering deposition machine, an FSTAR Scientific Instruments optical test system, a service life test system, and a Beijing Liangtang ellipsometer) in a manner familiar to those skilled in the art. Those skilled in the art are familiar with the relevant content, such as the use of the above-mentioned equipment and test methods, and can reliably and unaffectedly obtain specific data of the sample, so the above-mentioned relevant content will not be repeated in this specification.

[0075] [Material Synthesis Example] The preparation method of the compound according to the present invention is not limited. Taking the following compound as a typical but non-limiting example, its synthetic route and preparation method are as follows:

[0076] Example 1 Compound Ir(L a5 )(L b3 Synthesis of 2

[0077] Step 1: Synthesis of 3,3-dimethylpentyl-2-one [ka] 2,2-Dimethylbutyric acid (11.6 g, 100 mmol) was dissolved in 200 mL of ultra-dehydrated tetrahydrofuran. N2 was bubbled through the resulting solution for 3 minutes and then cooled to 0 °C. Then, under N2 protection, 230 mL of 1.3 M methyllithium in ethyl ether was added dropwise at 0 °C. After the addition was complete, the reaction mixture was maintained at 0 °C for 2 h. The temperature was then allowed to rise to room temperature and react overnight. After TLC showed the reaction was complete, 1 M hydrochloric acid was slowly added to quench the reaction, and the liquid was separated and the organic layer was collected. The aqueous phase was extracted twice with dichloromethane. The organic layers were combined, dried, and the solvent was removed using a rotary evaporator to obtain the desired product, 3,3-dimethylpentyl-2-one (11.0 g, 94%).

[0078] Step 2: Synthesis of 2,2-dimethylbutyryl chloride [ka] 2,2-Dimethylbutyric acid (11.6 g, 100 mmol) was dissolved in 200 mL of ultra-dehydrated dichloromethane, and one drop of ultra-dehydrated DMF was added dropwise as a catalyst. N2 was then bubbled through the resulting solution for 3 minutes and cooled to 0 °C. Then, under N2 protection, oxalyl chloride (14.0 g, 110 mmol) was added dropwise at 0 °C. After the addition was complete, the reaction was allowed to warm to room temperature. When no gas was being released from the reaction system, the solvent was removed from the reaction solution using a rotary evaporator. The resulting crude 2,2-dimethylbutyryl chloride could be used directly in the next reaction without further purification.

[0079] Step 3: Synthesis of 3,3,7,7-tetramethylnonane-4,6-dione [ka] 3,3-Dimethylpentyl-2-one (11.0 g, 96 mmol) was dissolved in 200 mL of ultra-dehydrated tetrahydrofuran. N2 was bubbled through the resulting solution for 3 minutes and then cooled to -78 °C. Then, under N2 protection, 53 mL of a 2 M solution of lithium diisopropylamide in tetrahydrofuran was added dropwise at -78 °C. After the addition was complete, the reaction mixture was maintained at -78 °C and allowed to react for 30 minutes. Then, 2,2-dimethylbutyryl chloride (Step 2) was slowly added. After the addition was complete, the reaction was allowed to warm slowly to room temperature and react overnight. The reaction was then quenched by slowly adding 1 M hydrochloric acid. The liquid was separated and the organic layer was collected. The aqueous phase was extracted twice with dichloromethane. The organic layers were combined, dried, and the solvent was removed using a rotary evaporator to obtain the crude product. Purification by column chromatography (eluent: petroleum ether) and distillation under reduced pressure gave the target product 3,3,7,7-tetramethylnonane-4,6-dione (3.6 g, 18%).

[0080] Step 4: Synthesis of iridium dimer [ka] A mixture of 2-(3,5-dimethylphenyl)quinoline (2.6 g, 11.3 mmol), iridium trichloride trihydrate (800 mg, 2.3 mmol), 2-ethoxyethanol (24 mL), and water (8 mL) was refluxed under nitrogen for 24 hours. After cooling to room temperature, the solvent was removed under reduced pressure to give the iridium dimer, which was used directly in the next step without further purification.

[0081] Step 5: Compound Ir(L a5 )(L b3 Synthesis of 2 [ka] A mixture of the dimer (1.15 mmol), 3,3,7,7-tetramethylnonane-4,6-dione (977 mg, 4.6 mmol), potassium carbonate (1.6 g, 11.5 mmol), and 2-ethoxyethanol (32 mL) was stirred under a nitrogen atmosphere at room temperature for 24 hours. The precipitate was filtered through diatomaceous earth and washed with ethanol. Dichloromethane was added to the resulting solid, and the filtrate was collected. Ethanol was then added, and the resulting solution was concentrated, but not to dryness. After filtration, 1.3 g of product was obtained. The product was further purified by column chromatography. The structure of the compound was confirmed by NMR and LC-MS to be the target product with a molecular weight of 868.

[0082] Example 2 Compound Ir(L a26 )(L b3 Synthesis of 2

[0083] Step 1: Synthesis of ethyl 2-ethyl-2-methylbutyrate [ka] Ethyl 2-ethylbutyrate (50.0 g, 346 mmol) was dissolved in 600 mL of ultra-dry tetrahydrofuran. N2 was bubbled through the resulting solution for 3 minutes and then cooled to -78 °C. Then, under N2 protection, 190 mL of a 2 M solution of lithium diisopropylamide in tetrahydrofuran was added dropwise at -78 °C. After the addition was complete, the reaction mixture was maintained at -78 °C and allowed to react for 30 minutes. Methyl iodide (58.9 g, 415 mmol) was then slowly added dropwise. After the addition was complete, the reaction was allowed to warm slowly to room temperature and react overnight. Saturated ammonium chloride solution was then slowly added to quench the reaction. The solution was separated and the organic layer was collected. The aqueous phase was extracted twice with dichloromethane. The organic layers were combined, dried, and the solvent removed by rotary evaporation to yield the desired product, i.e., ethyl 2-ethyl-2-methylbutyrate (52.2 g, 95%).

[0084] Step 2: Synthesis of 2-ethyl-2-methylbutyric acid [ka] Ethyl 2-ethyl-2-methylbutyrate (52.2 g, 330 mmol) was dissolved in methanol, and sodium hydroxide (39.6 g, 990 mmol) was added. The resulting reaction mixture was heated and refluxed for 12 hours. After cooling to room temperature, the methanol was spin-dried, and 3 M hydrochloric acid was added to adjust the pH of the reaction mixture to 1. The mixture was then extracted multiple times with dichloromethane. The organic layers were combined, dried, and the solvent was removed using a rotary evaporator to yield 2-ethyl-2-methylbutyric acid (41.6 g, 97%).

[0085] Step 3: Synthesis of 3-ethyl-3-methyl-pentan-2-one [ka] 2-Ethyl-2-methylbutyric acid (13.0 g, 100 mmol) was dissolved in 200 mL of ultra-dehydrated tetrahydrofuran. N2 was bubbled through the resulting solution for 3 minutes and then cooled to 0 °C. Then, under N2 protection, 230 mL of a 1.3 M ethyllithium ethyl ether solution was added dropwise at 0 °C. After the addition was complete, the reaction mixture was maintained at 0 °C and allowed to react for 2 h. The temperature was then allowed to rise to room temperature and react overnight. After TLC showed the reaction was complete, 1 M hydrochloric acid was added to quench the reaction. The liquid was separated and the organic layer was collected. The aqueous phase was extracted twice with dichloromethane. The organic layers were combined, dried, and the solvent was removed using a rotary evaporator to obtain the target product, 3-ethyl-3-methyl-pentan-2-one (11.8 g, 92%).

[0086] Step 4: Synthesis of 2-ethyl-2-methylbutyryl chloride [ka] 2-Ethyl-2-methylbutyric acid (13.0 g, 100 mmol) was dissolved in 200 mL of ultra-dry dichloromethane, and one drop of ultra-dry DMF was added as a catalyst. N2 was bubbled through the resulting solution for 3 minutes and then cooled to 0 °C. Under N2 protection, oxalyl chloride (14.0 g, 110 mmol) was added dropwise at 0 °C. After the addition was complete, the reaction was allowed to warm to room temperature. When no gas was being released from the reaction system, the solvent was removed from the reaction solution using a rotary evaporator. The resulting crude 2-ethyl-2-methylbutyryl chloride could be used directly in the next reaction without further purification.

[0087] Step 5: Synthesis of 3,7-diethyl-3,7-dimethylnonane-4,6-dione [ka] 3-Ethyl-3-methyl-pentan-2-one (11.8 g, 92 mmol) was dissolved in ultra-dehydrated tetrahydrofuran. N2 was bubbled through the resulting solution for 3 minutes and then cooled to -78 °C. Then, under N2 protection, 51 mL of a 2 M solution of lithium diisopropylamide in tetrahydrofuran was added dropwise at -78 °C. After the addition was complete, the reaction mixture was maintained at -78 °C and allowed to react for 30 minutes. Then, 2-ethyl-2-methylbutyryl chloride (Step 4) was slowly added. After the addition was complete, the reaction was allowed to warm slowly to room temperature and react overnight. The reaction was then quenched by slowly adding 1 M hydrochloric acid. The liquid was separated and the organic layer was collected. The aqueous phase was extracted twice with dichloromethane, and the organic layers were combined, dried, and the solvent removed by rotary evaporation to obtain the crude product, which was purified by column chromatography (eluent: petroleum ether) and distilled under reduced pressure to obtain the target product 3,7-diethyl-3,7-dimethylnonane-4,6-dione (4.6 g, 21%).

[0088] Step 6: Compound Ir(L a26 )(L b3 Synthesis of 2 [ka] A mixture of the dimer (1.15 mmol), 3,7-diethyl-3,7-dimethyldecane-4,6-dione (1.1 g, 4.6 mmol), potassium carbonate (1.6 g, 11.5 mmol), and 2-ethoxyethanol (30 mL) was stirred under a nitrogen atmosphere at room temperature for 24 hours. The precipitate was filtered through diatomaceous earth and washed with ethanol. Dichloromethane was added to the resulting solid, and the filtrate was collected. Ethanol was then added, and the resulting solution was concentrated, but not to dryness. After filtration, 1.4 g of product was obtained. The product was further purified by column chromatography. The structure of the compound was confirmed by NMR and LC-MS to be the target product with a molecular weight of 896.

[0089] Example 3 Compound Ir(L a6 )(L b3 Synthesis of 2

[0090] Step 1: Synthesis of 2-ethylbutyryl chloride [ka] 2-Ethylbutyric acid (11.6 g, 100 mmol) was dissolved in ultra-dehydrated dichloromethane, and one drop of ultra-dehydrated DMF was added as a catalyst. N2 was bubbled through the resulting solution for 3 minutes and then cooled to 0 °C. Protected with N2, oxalyl chloride (14.0 g, 110 mmol) was added dropwise at 0 °C. After the addition was complete, the reaction was allowed to warm to room temperature. When no gas was being released from the reaction system, the solvent was removed from the reaction solution using a rotary evaporator. The resulting crude 2-ethylbutyryl chloride could be used directly in the next reaction without further purification.

[0091] Step 2: Synthesis of 7-ethyl-3,3-dimethylnonane-4,6-dione [ka] 3,3-Dimethylpentyl-2-one (10.3 g, 90 mmol) was dissolved in 180 mL of ultra-dehydrated tetrahydrofuran. N2 was bubbled through the resulting solution for 3 minutes and then cooled to -78 °C. Then, under N2 protection, 50 mL of a 2 M solution of lithium diisopropylamide in tetrahydrofuran was added dropwise at -78 °C. After the addition was complete, the reaction mixture was maintained at -78 °C and allowed to react for 30 minutes. Then, 2-ethylbutyryl chloride (from step 1) was slowly added. After the addition was complete, the reaction was allowed to warm slowly to room temperature and react overnight. Then, 1 M hydrochloric acid was slowly added to quench the reaction. The liquid was separated and the organic layer was collected. The aqueous phase was extracted twice with dichloromethane, and the organic layers were combined, dried, and the solvent was removed by rotary evaporation to obtain the crude product, which was purified by column chromatography (eluent: petroleum ether) and distilled under reduced pressure to obtain the target product 7-ethyl-3,3-dimethylnonane-4,6-dione (4.2 g, 22%).

[0092] Step 3: Compound Ir(L a6 )(L b3 Synthesis of 2 [ka] A mixture of the dimer (1.15 mmol), 7-ethyl-3,3-dimethylnonane-4,6-dione (977 mg, 4.6 mmol), potassium carbonate (1.6 g, 11.5 mmol), and 2-ethoxyethanol (30 mL) was stirred under a nitrogen atmosphere at room temperature for 24 hours. The precipitate was filtered through diatomaceous earth and washed with ethanol. Dichloromethane was added to the resulting solid, and the filtrate was collected. Ethanol was then added, and the resulting solution was concentrated, but not to dryness. After filtration, 1.3 g of product was obtained. The product was further purified by column chromatography. The structure of the compound was confirmed by NMR and LC-MS to be the target product with a molecular weight of 868.

[0093] Example 4 Compound Ir(L a21 )(L b3Synthesis of 2

[0094] Step 1: Synthesis of 3,7-diethyl-3-methylnonane-4,6-dione [ka] 3-Ethyl-3-methyl-pentan-2-one (11.8 g, 92 mmol) was dissolved in ultra-dehydrated tetrahydrofuran. N2 was introduced into the resulting solution and bubbled through for 3 minutes, then the solution was cooled to -78°C. Then, under N2 protection, 55 mL of a 2 M solution of lithium diisopropylamide in tetrahydrofuran was added dropwise at -78°C. After the addition was complete, the reaction mixture was maintained at -78°C and allowed to react for 30 minutes. Then, 2-ethylbutyryl chloride (Step 1 in Example 3) was slowly added. After the addition was complete, the reaction was allowed to warm slowly to room temperature and react overnight. Then, 1 M hydrochloric acid was slowly added to quench the reaction. The liquid was separated, and the organic layer was collected. The aqueous phase was extracted twice with dichloromethane, and the organic layers were combined, dried, and the solvent was removed by rotary evaporation to obtain the crude product, which was purified by column chromatography (eluent: petroleum ether) and distilled under reduced pressure to obtain the target product 3,7-diethyl-3-methylnonane-4,6-dione (4.7 g, 23%).

[0095] Step 2: Compound Ir(L a21 )(L b3 Synthesis of 2 [ka] A mixture of the dimer (1.15 mmol), 3,7-diethyl-3-methylnonane-4,6-dione (1.0 g, 4.6 mmol), potassium carbonate (1.6 g, 11.5 mmol), and 2-ethoxyethanol (30 mL) was stirred under a nitrogen atmosphere at room temperature for 24 hours. The precipitate was filtered through diatomaceous earth and washed with ethanol. Dichloromethane was added to the resulting solid and the filtrate was collected. Ethanol was then added and the resulting solution was concentrated, but not to dryness. After filtration, 1.5 g of product was obtained. The product was further purified by column chromatography. The structure of the compound was confirmed by NMR and LC-MS to be the target product with a molecular weight of 882.

[0096] Example 5 Compound Ir(L a26 )(L b135 Synthesis of 2

[0097] Step 1: Synthesis of iridium dimer [ka] A mixture of 1-(3,5-dimethylphenyl)-6-isopropylisoquinoline (2.0 g, 7.3 mmol), iridium trichloride trihydrate (854 mg, 2.4 mmol), 2-ethoxyethanol (24 mL), and water (8 mL) was refluxed under nitrogen for 24 hours. After cooling to room temperature, the solid was filtered and washed multiple times with methanol and dried to give the iridium dimer (1.3 g, 70%).

[0098] Step 2: Compound Ir(L a26 )(L b135 Synthesis of 2 [ka] A mixture of the dimer (1.3 g, 0.8 mmol), 3,7-diethyl-3,7-dimethylnonane-4,6-dione (769 mg, 3.2 mmol), potassium carbonate (1.1 g, 8.0 mmol), and 2-ethoxyethanol (20 mL) was stirred under a nitrogen atmosphere at room temperature for 24 hours. The precipitate was filtered through diatomaceous earth and washed with ethanol. Dichloromethane was added to the resulting solid, and the filtrate was collected. Ethanol was then added, and the resulting solution was concentrated, but not to dryness. After filtration, 1.2 g of product was obtained. The product was further purified by column chromatography. The structure of the compound was confirmed by NMR and LC-MS to be the target product with a molecular weight of 980.

[0099] Those skilled in the art should know that the methods for preparing the above compounds are merely exemplary and can be modified to obtain the structures of other compounds of the present invention.

[0100] [Embodiment of the device] First, a glass substrate with a 120 nm thick indium tin oxide (ITO) anode was cleaned and then treated with oxygen plasma and UV ozone. After treatment, the substrate was dried in a glove box to remove water. The substrate was then attached to a substrate holder and placed in a vacuum chamber. Below, for the specified organic layer, the vacuum degree is 10 -8In the case of a 1000-kV LED, the layers were sequentially deposited on an ITO anode by hot vacuum evaporation at a rate of 0.2 to 2 Å / s. Compound HI was used as a hole-injection layer (HIL). Compound HT was used as a hole-transport layer (HTL). Compound EB was used as an electron-blocking layer (EBL). Then, a compound according to the present invention or a comparative compound was doped into a host compound RH to form an emitting layer (EML). Compound HB was used as a hole-blocking layer (HBL). In the HBL, a mixture of compound ET and 8-hydroxyquinoline-lithium (Liq) was deposited as an electron-transporting layer (ETL). Finally, a 1-nm-thick layer of Liq was deposited as an electron-injection layer, and a 120-nm-thick layer of Al was deposited as a cathode. The device was then transferred to a glove box and encapsulated using a glass cover and a moisture absorbent to complete the device.

[0101] The detailed layer structure and thickness of the device are shown in the table below: For layers in which more than one material is used, it is obtained by doping different compounds in the weight ratios listed.

[0102] Table 1: Device structure in device examples [Table 1-1] [Table 1-2]

[0103] The structure of the material used in the element is represented as follows: [ka] [ka]

[0104] The IVL of the devices was measured at different current densities and voltages. At 1000 nits, the luminous efficacy (LE), external quantum efficiency (EQE), maximum emission wavelength (λmax), full width at half maximum (FWHM), voltage (V) and CIE data were measured. The sublimation temperature (Sub T) of the materials was tested.

[0105] Table 2: Element data [Table 2]

[0106] 〔summary〕 As can be seen from Table 2, the examples of devices containing the compounds according to the present invention exhibit several advantages over the comparative compounds. Compared to the comparative compounds, the compounds according to the present invention have narrower half-widths, higher external quantum efficiencies, and can produce red-shift effects. For example, Example 1 has the same quinoline ligand as Comparative Example 1, but according to the embodiment of the present invention, Example 1 is redder and at the same time has higher external quantum efficiencies and luminous efficiencies. Furthermore, for example, Example 5 has the same isoquinoline ligand as Comparative Example 2, but according to the embodiment of the present invention, Example 5 can achieve the deep red color obtained with 3% red light-emitting material in the comparative example by doping only 2% red light-emitting material, and its external quantum efficiencies and luminous efficiencies are higher. Furthermore, although its sublimation temperature is relatively high compared to the isoquinoline ligand complex, according to the embodiment of the present invention, the red light-emitting material Ir(L) in Example 5 can be doped at a lower temperature. a26 )(L b135 )2 is 23° C. lower than the sublimation temperature of the red light-emitting material compound B in Comparative Example 2.

[0107] It should be understood that the various embodiments described herein are illustrative only and are not intended to limit the scope of the present invention. Therefore, it will be apparent to those skilled in the art that the invention sought to be protected includes variations on the specific and preferred embodiments described herein. Many of the materials and structures described herein can be substituted with other materials and structures without departing from the spirit of the present invention. It should be understood that the various theories as to why the present invention works are not limiting.

Claims

1. An organic layer, the organic layer comprising: Ir(L ａ ) ｍ (L ｂ ) ｎ and a metal complex having the general formula: L ｂ is a second ligand coordinated to Ir, and L ｂ may be the same or different, and L ａ and L ｂ may be linked to form a multidentate ligand; m is 1 and n is 2; Ligand L ａ is an organic layer having a structure represented by Formula 1. 【Chemistry 1】 (Formula 1) (R １ ~R ７ are each independently selected from the group consisting of hydrogen, deuterium, halogen, a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms, and combinations thereof; R １ , R ２ , R ３ and R ４ , R ５ , R ６ at least one group contains three identical or different substituents; the three identical or different substituents each contain at least one carbon atom; At least two of the three identical or different substituents contain at least two carbon atoms; Substituent R １ and R ２ and R ３ or between the substituents R ４ and R ５ and R ６ Three adjacent substituents between do not combine to form a ring, L ｂ is, independently, 【Chemistry 2】 Selected from R ａ and R ｂ may represent mono-, di-, tri-, tetra- or unsubstituted; R ａ and R ｂ are each independently selected from the group consisting of hydrogen, deuterium, halogen, a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms, a substituted or unsubstituted cycloalkyl group having 3 to 20 ring carbon atoms, a substituted or unsubstituted alkoxy group having 1 to 20 carbon atoms, a substituted or unsubstituted aryloxy group having 6 to 30 carbon atoms, a substituted or unsubstituted alkenyl group having 2 to 20 carbon atoms, a substituted or unsubstituted aryl group having 6 to 30 carbon atoms, a substituted or unsubstituted heteroaryl group having 3 to 30 carbon atoms, a substituted or unsubstituted alkylsilyl group having 3 to 20 carbon atoms, a thiol group, and combinations thereof; two adjacent substituents may be bonded to form a ring; The metal complex does not include the following structure: 【Transformation 3】 ）

2. The organic layer according to claim 1 , wherein the organic layer is a light-emitting layer and the metal complex is a light-emitting material.

3. R １ ~R ７ are each independently selected from the group consisting of hydrogen, deuterium, halogen, a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms, and combinations thereof; L ｂ are each independently 【Chemistry 4】 selected from the group consisting of R ａ and R ｂ may represent mono-, di-, tri-, tetra- or unsubstituted; R ａ and R ｂ are each independently selected from the group consisting of hydrogen, deuterium, halogen, a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms, a substituted or unsubstituted cycloalkyl group having 3 to 20 ring carbon atoms, an unsubstituted alkoxy group having 1 to 20 carbon atoms, a substituted or unsubstituted alkenyl group having 2 to 20 carbon atoms, a substituted or unsubstituted aryl group having 6 to 30 carbon atoms, a substituted or unsubstituted heteroaryl group having 3 to 30 carbon atoms, and combinations thereof; Two adjacent substituents R ａ may be bonded to each other to form a ring, and two adjacent substituents R ａ and R ｂ The organic layer according to claim 1 , wherein the groups may be bonded to form a ring.

4. R １ ~R ７ are each independently selected from the group consisting of hydrogen, deuterium, fluorine, a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms, and combinations thereof; L ｂ are each independently 【Transformation 5】 selected from the group consisting of R ａ and R ｂ may represent mono-, di-, tri-, tetra- or unsubstituted; R ａ and R ｂ are each independently selected from the group consisting of hydrogen, deuterium, halogen, a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms, an unsubstituted alkoxy group having 1 to 20 carbon atoms, a substituted or unsubstituted alkenyl group having 2 to 20 carbon atoms, a substituted or unsubstituted aryl group having 6 to 30 carbon atoms, and combinations thereof; Two adjacent substituents R ａ may be bonded to each other to form a ring, and two adjacent substituents R ａ and R ｂ The organic layer according to claim 1 , wherein the groups may be bonded to form a ring.

5. R ４ ~R ７ are each independently selected from the group consisting of hydrogen, deuterium, a methyl group, an ethyl group, an isopropyl group, an isobutyl group, a neopentyl group, fluorine, a trifluoromethyl group, 2,2,2-trifluoroethyl, 3,3,3-trifluoropropyl, 3,3,3-trifluoro-2,2-dimethylpropyl, and deuterated versions of each of the above groups; R １ ~R ２ are each independently selected from the group consisting of an ethyl group, an isopropyl group, an isobutyl group, a neopentyl group, 2,2,2-trifluoroethyl, 3,3,3-trifluoropropyl, 3,3,3-trifluoro-2,2-dimethylpropyl, and deuterated versions of each of the above groups; R ３ are each independently selected from the group consisting of a methyl group, an ethyl group, an isopropyl group, an isobutyl group, a neopentyl group, a trifluoromethyl group, 2,2,2-trifluoroethyl, 3,3,3-trifluoropropyl, 3,3,3-trifluoro-2,2-dimethylpropyl, and deuterated versions of any of the above groups.

6. R ４ The organic layer of claim 5 , wherein is selected from hydrogen or deuterium.

7. The ligand L ａ teeth, 【Transformation 6】 【change】 【change】 【change】 Selected from The ligand L ａ The organic layer of claim 1 , wherein:

8. An electroluminescent device that emits red or white light, comprising the organic layer of claim 1.

9. The organic layer of claim 1 , wherein the organic layer further comprises a host compound.

10. 10. The organic layer according to claim 9, wherein the host compound comprises at least one chemical group selected from the group consisting of benzene, biphenyl, pyridine, pyrimidine, triazine, carbazole, azacarbazole, indolocarbazole, dibenzothiophene, azadibenzothiophene, dibenzofuran, azadibenzofuran, dibenzoselenophene, azadibenzoselenophene, triphenylene, azatriphenylene, fluorenyl, silicon fluorene, naphthalene, quinoline, isoquinoline, quinazoline, quinoxaline, phenanthrene, azaphenanthrene, and combinations thereof.

11. An electronic component module comprising an electroluminescent device comprising the organic layer according to any one of claims 1 to 7 and 9 to 10.

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