A metal complex and its application

Abstract

The present invention relates to a metal platinum complex and its application. When used in OLEDs, especially in the blue light emitting region, the metal platinum complex exhibits enhanced phosphorescence quantum yield, good luminescence stability, and high luminescence efficiency. The complex is suitable for use as an emitter material in OLED applications. The metal platinum complex of the present invention can produce an organic electroluminescent device with deep blue electroluminescence and improved luminescence efficiency, and the light-emitting device has good thermal stability. The metal platinum complex of the present invention regulates its photophysical properties by adjusting the structure of ligands surrounding the metal center and the structure of substituents on the ligands. The complex has the advantages of a narrow emission spectrum, high stability, and high efficiency, and has broad application prospects in many fields of OLED displays and lighting.

Description

Technical Field

[0001] The present invention belongs to the technical field of luminescent materials, and in particular relates to a metal complex and applications thereof. Background Art

[0002] OLEDs (Organic Light Emitting Diodes) utilize organic thin films that emit light when a voltage is applied across the device. OLEDs are becoming an increasingly attractive technology for applications such as flat panel displays, lighting, and backlighting.

[0003] One application of phosphorescent emitting molecules is in full-color displays. Industry standards for such displays require pixels suitable for emitting specific colors. Specifically, these standards require saturated red, green, and blue pixels. Currently, OLEDs of all sizes utilize red and green phosphorescent materials with 100% luminous efficiency. However, no blue phosphorescent material has yet been commercialized, and the luminous efficiency of blue fluorescent materials is only 25%. Although a variety of blue-emitting materials have been extensively researched and developed, such as inorganic phosphors, metal complexes, and thermally activated delayed fluorescence materials, triplet excitons in phosphorescent materials have numerous dissipation pathways, such as non-radiative transitions, delayed fluorescence, triplet-triplet annihilation, and quenching by oxygen and water vapor, which severely hinder the improvement of phosphorescent performance. The discovery that crystal engineering can exploit strong intermolecular interactions to effectively suppress the non-radiative transitions of triplet excitons and, due to its dense molecular packing, reduce quenching of triplet excitons by oxygen and water vapor, has become an effective approach to achieving high-efficiency room-temperature phosphorescence. However, in the aggregated state, intermolecular π-π stacking easily leads to triplet-triplet annihilation, which dissipates a large amount of triplet excitons and affects the improvement of phosphorescence efficiency. In addition, π-π stacking increases the degree of intermolecular conjugation, red-shifting the emission and making it difficult to achieve blue phosphorescence. How to create long-life, high-efficiency blue phosphorescence is one of the challenges facing the field of organic phosphorescent materials.

[0004] In view of the above reasons, the present invention is proposed. Summary of the Invention

[0005] In order to solve the above problems existing in the prior art, the present invention provides a metal complex and its application. When the metal complex is used in OLED, especially when used in the blue light emitting region, it exhibits enhanced phosphorescence quantum yield and is suitable for use as an emitter material in OLED applications.

[0006] The first object of the present invention is to provide a metal complex having good electroluminescent stability and excellent luminous efficiency.

[0007] The second object of the present invention is to provide a use of the metal complex in an organic electroluminescent device.

[0008] The third object of the present invention is to provide a consumer product comprising the metal complex.

[0009] In order to achieve the above object, the present invention adopts the following technical solutions:

[0010] A metal complex, characterized in that the general formula of formula (I) is:

[0011]

[0012] wherein Ring A, Ring B, and Ring C are each a 5-membered carbocyclic ring, a 5-membered heterocyclic ring, a 6-membered carbocyclic ring, or a 6-membered heterocyclic ring;

[0013] X 1 ~X 6 are each independently selected from C or N;

[0014] R 1 、R 2 、R 5 、R 6 、R 7 Each represents mono- or poly-substituted to saturated substitution, or unsubstituted;

[0015] R 3 、R 4 Each represents mono- or di-substitution;

[0016] L 1 , L 2 Each is independently selected from a single bond, or a divalent group;

[0017] R 1 ~R 7 Each is independently selected from hydrogen or the group consisting of: deuterium, halogen atoms, nitrile groups, acyl groups, carboxyl groups, ether groups, ester groups, isonitrile groups, sulfide groups, selenoyl groups, sulfinyl groups, sulfonyl groups, phosphine groups, groups with C1 to C 40 Straight chain alkyl with C1~C 40 Straight chain heteroalkyl with C3~C 40 Branched or cyclic alkyl groups with C1 to C 40 Alkoxy, with C6~C 60 Arylalkyl, with C6~C 60 Aryloxy, with C6~C 60 Aromatic amino group, with C3~C 40 Silane groups with C2~C 40 Alkenyl, with C4~C 40 Cycloalkenyl, with C2~C 40 Heteroalkenyl, with C2~C 40 Alkynyl, with C6~C 60 Aryl, with C2~C60 Heteroaryl and combinations thereof, any adjacent two or more R 1 、R 2 、R 3 、R 4 、R 5 、R 6 、R 7 They may be optionally joined or fused to form a substituted or unsubstituted ring.

[0018] Preferably, the ring A is a 5-membered heteroaromatic ring.

[0019] Preferably, the ring B is a 6-membered aromatic ring or a heteroaromatic ring.

[0020] Preferably, the ring C is a 5-membered heteroaromatic ring, a 6-membered aromatic ring or a heteroaromatic ring.

[0021] Preferably, the metal complex is selected from the group consisting of:

[0022]

[0023]

[0024] wherein Y each independently represents O or S;

[0025] R 1 ~R 7 , L 1 , L 2 The definition of is the same as that of the above formula (I).

[0026] The "divalent group" of the present invention is a divalent linking functional group, and non-limiting examples thereof include -O-, -S-, -(S=O)-, -(SO2)-, -(CH2)-, -(C=O)-, -Se-, -(Se=O), -(SeO2), -(NR 8 )-、-(PR 8 )-、-(P=OR 8 )-、-(CR 8 R 9 )-or-(SiR 8 R 9 )-wait.

[0027] Furthermore, the L 1 , L 2 Each independently selected from a single bond, O, S, S=O, SO2, Se, NR 8 PR 8 、R 8 P=O、CR 8 R 9 、C=O、SiR 8 R9 ,GeR 8 R 9 BR 8 , or a group consisting of the following groups:

[0028]

[0029]

[0030] wherein n is selected from 0, 1, 2 or 3;

[0031] R 8 、R 9 、R 10 、R 11 、R 12 Each is independently selected from hydrogen or the group consisting of: deuterium, halogen atoms, nitrile groups, acyl groups, carboxyl groups, ether groups, ester groups, isonitrile groups, sulfide groups, selenoyl groups, sulfinyl groups, sulfonyl groups, phosphine groups, groups with C1 to C 40 Straight chain alkyl with C1~C 40 Straight chain heteroalkyl with C3~C 40 Branched or cyclic alkyl groups with C1 to C 40 Alkoxy, with C6~C 60 Arylalkyl, with C6~C 60 Aryloxy, with C6~C 60 Aromatic amino group, with C3~C 40 Silane groups with C2~C 40 Alkenyl, with C4~C 40 Cycloalkenyl, with C2~C 40 Heteroalkenyl, with C2~C 40 Alkynyl, with C6~C 60 Aryl, with C2~C 60 Heteroaryl and combinations thereof; any adjacent two or more R 8 、R 9 、R 10 、R 11 、R 12 They may be optionally joined or cyclized to form substituted or unsubstituted rings.

[0032] Furthermore, the R 1 、R 2 、R 3 、R 4 、R 5 、R 6 、R 7 、R 8 、R 9 、R 10 、R11 、R 12 Each independently selected from hydrogen atom, deuterium atom, fluorine, nitrile group, isonitrile group, R A1 ~R A30 、R B1 ~R B195 、R C1 ~R C80 the group formed;

[0033] Among them, R A1 ~R A30 The structural formula is shown below:

[0034]

[0035] R B1 ~R B195 The structure shown is as follows:

[0036]

[0037]

[0038]

[0039]

[0040] R C1 ~R C80 The structure shown is as follows:

[0041]

[0042]

[0043]

[0044] Each hydrogen atom in each substituent may be replaced by a deuterium atom.

[0045] Furthermore, the R 8 、R 9 、R 10 、R 11 、R 12 are each independently selected from the group consisting of: R A1 ~R A26 、R B1 ~R B185 、R C1 ~R C79 .

[0046] In the present invention, "ring" in the substituted or unsubstituted ring formed by the bonding of adjacent groups refers to a substituted or unsubstituted hydrocarbon ring or a substituted or unsubstituted heterocycle. A condensed ring refers to a condensed aliphatic ring, a condensed aromatic ring, a condensed aliphatic heterocycle, a condensed aromatic heterocycle, or a combination thereof.

[0047] The 5-membered carbocycle described in the present invention refers to a monocyclic or polycyclic ring system having 5 carbon atoms. A polycyclic ring refers to two or more rings in which two carbon atoms are shared by two adjacent rings. For example, the 5-membered carbocycle can be cyclopentane, cyclopentene, 2,3-dihydroindene, indene, etc. A 5-membered heterocycle refers to a 5-membered carbocycle containing at least one heteroatom, wherein the total number of heteroatoms and carbon atoms constituting the ring is 5. The heteroatoms include, but are not limited to, oxygen, sulfur, nitrogen, phosphorus, boron, silicon, or selenium. In many cases, oxygen, sulfur, or nitrogen are preferred heteroatoms. Non-limiting examples of 5-membered heterocycles include pyrazole, imidazole, oxazole, thiazole, triazole, oxadiazole, oxatriazole, dioxazole, thiadiazole, benzimidazole, benzoxazole, benzotriazole, etc.

[0048] The 6-membered carbocyclic ring described in the present invention is a monocyclic or polycyclic ring system having 6 carbon atoms. Preferably, the 6-membered carbocyclic ring refers to an aryl group described in the present invention. A 6-membered heterocyclic ring refers to a ring system having a total of 6 heteroatoms and carbon atoms. Preferably, the 6-membered heterocyclic ring refers to a 6-membered heteroaryl group, such as pyridine, pyridazine, pyrimidine, pyrazine, triazine, oxazine, oxathiazine, oxadiazine, quinoline, isoquinoline, cinnoline, quinazoline, quinoxaline, naphthyridine, phthalazine, pteridine, and the like.

[0049] "Aryl" according to the present invention refers to and includes monocyclic aromatic hydrocarbon groups and polycyclic aromatic ring systems. Polycyclic rings may have two or more rings in which two carbons are shared by two adjacent rings (the rings are "fused"), wherein at least one of the rings is an aromatic hydrocarbon group, for example the other rings may be cycloalkyl, cycloalkenyl, aryl, heterocycle and / or heteroaryl. Preferred aryl groups are those containing 6 to 30 carbon atoms, preferably 6 to 20 carbon atoms, more preferably 6 to 12 carbon atoms. Especially preferred are aryl groups with six carbons, ten carbons or twelve carbons. Suitable aryl groups include phenyl, biphenyl, terphenyl, triphenylene, tetraphenylene, naphthyl, anthracenyl, phenanthrenyl, fluorenyl, pyrenyl, perylenyl, The aryl group may be optionally substituted, preferably phenyl, biphenyl, terphenyl, triphenylene, fluorenyl and naphthyl.

[0050] "Heteroaryl" within the meaning of the present invention refers to and includes monocyclic aromatic groups and polycyclic aromatic ring systems that include at least one heteroatom. Heteroatoms include, but are not limited to, oxygen, sulfur, nitrogen, phosphorus, boron, silicon, or selenium. In many cases, oxygen, sulfur, or nitrogen are preferred heteroatoms. Monocyclic heteroaromatic systems are preferably monocyclic rings having 5 or 6 ring atoms, and the rings may have from one to six heteroatoms. Heteropolycyclic ring systems may have two or more rings in which two atoms are common to two adjacent rings (the rings are "fused"), wherein at least one of the rings is a heteroaryl group, for example, the other rings may be cycloalkyl, cycloalkenyl, aryl, heterocycle, and / or heteroaryl groups. Heteropolycyclic aromatic ring systems may have from one to six heteroatoms in each ring of the polycyclic aromatic ring system. Preferred heteroaryl groups are heteroaryl groups containing from three to thirty carbon atoms, preferably from three to twenty carbon atoms, and more preferably from three to twelve carbon atoms. Suitable heteroaryl groups include dibenzothiophenyl, dibenzofuranyl, dibenzoselenophene, furyl, thienyl, benzofuranyl, benzothiophenyl, benzoselenophene, carbazolyl, indolocarbazolyl, pyridylindolyl, pyrrolodipyridyl, pyrazolyl, imidazolyl, triazolyl, oxazolyl, thiazolyl, oxadiazolyl, oxatriazolyl, dioxazolyl, thiadiazolyl, pyridyl, pyridazinyl, pyrimidinyl, pyrazinyl, triazinyl, oxazinyl, oxathiazinyl, oxadiazinyl, indolyl, benzimidazolyl, indazolyl, indoxazolyl, benzoxazolyl, benzisoxazolyl, benzothiazolyl, quinolinyl, isoquinolinyl, cinnolinyl, quinazolinyl, quinoxalinyl, naphthyridinyl, phthalazinyl, Pteridinyl, xanthene (xanthene) base, acridinyl, phenazinyl, phenothiazinyl, phenoxazinyl, benzofuropyridinyl, furodipyridinyl, benzothienopyridinyl, thienodipyridinyl, benzoselenopyridinyl, selenophenodipyridinyl, 1,2-azaboryl, 1,3-azaboryl, 1,4-azaboryl, borazynyl and its aza analogs, preferably dibenzothienyl, dibenzofuranyl, dibenzoselenophenyl, carbazolyl, indolocarbazolyl, imidazolyl, pyridinyl, triazinyl, benzimidazolyl, 1,2-azaboryl, 1,3-azaboryl, 1,4-azaboryl, borazynyl and its aza analogs. In addition, the heteroaryl group can be optionally substituted.

[0051] Alkyl within the meaning of the present invention is a straight-chain or branched alkyl radical having 1 to 40 carbon atoms, in which individual hydrogen atoms or -CH2- groups may also be replaced, and an alkenyl or alkynyl radical having at least two carbon atoms. Alkyl, alkenyl or alkynyl is preferably taken to mean, by way of non-limiting example, the following radicals: methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, sec-butyl, tert-butyl, 2-methylbutyl, n-pentyl, sec-pentyl, neopentyl, cyclopentyl, n-hexyl, neohexyl, cyclohexyl, n-heptyl, cycloheptyl, n-octyl, cyclooctyl, 2-ethylhexyl, cyclohexenyl, heptenyl, cycloheptenyl, octenyl, cyclooctenyl, ethynyl, propynyl, butynyl, pentynyl, hexynyl, heptynyl or octynyl.

[0052] Alkoxy groups preferably having 1 to 40 carbon atoms are taken to mean methoxy, trifluoromethoxy, ethoxy, n-propoxy, isopropoxy, n-butoxy, isobutoxy, sec-butoxy, tert-butoxy, n-pentoxy, sec-pentoxy, 2-methylbutoxy, n-hexyloxy, cyclohexyloxy, n-heptyloxy, cycloheptyloxy, n-octyloxy, cyclooctyloxy, 2-ethylhexyloxy, pentafluoroethoxy and 2,2,2-trifluoroethoxy.

[0053] Heteroalkyl is preferably an alkyl radical having 1 to 40 carbon atoms and is understood to mean a radical in which individual hydrogen atoms or -CH2- groups are replaced by oxygen, sulfur or halogen atoms and is taken to mean alkoxy, alkylthio, fluorinated alkoxy, fluorinated alkylthio, in particular methoxy, ethoxy, n-propoxy, isopropoxy, n-butoxy, isobutoxy, sec-butoxy, tert-butoxy, methylthio, ethylthio, n-propylthio, isopropylthio, n-butylthio, isobutylthio, sec-butylthio, tert-butylthio, trifluoromethylthio, trifluoromethoxy, pentafluoroethoxy, pentafluoroethylthio, 2,2,2-trifluoroethoxy, 2,2,2-trifluoroethylthio, vinyloxy, vinylthio, propenyloxy, propenylthio, butenylthio, butenyloxy, pentenyloxy, pentenylthio, cyclopentenyloxy, cyclopentenylthio, hexenyloxy, hexenylthio, cyclohexenyloxy, cyclohexenylthio, ethynyloxy, ethynylthio, propynyloxy, propynylthio, butynyloxy, butynylthio, pentynyloxy, pentynylthio, hexynyloxy, hexynylthio.

[0054] Generally speaking, the cycloalkyl and cycloalkenyl groups according to the present invention may be cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, cyclobutenyl, cyclopentenyl, cyclohexenyl, cycloheptyl, or cycloheptenyl, wherein one or more -CH2- groups may be replaced by the above groups; in addition, one or more hydrogen atoms may be replaced by a deuterium atom, a halogen atom, or a nitrile group.

[0055] The alkenyl or alkynyl group according to the present invention has 2 to 40 carbon atoms, and the alkenyl or alkynyl group in which individual hydrogen atoms may be substituted is preferably vinyl, propenyl, butenyl, isobutenyl, styryl, distyryl, ethynyl, propynyl, butynyl, phenylethynyl; in addition, one or more hydrogen atoms may be replaced by a deuterium atom, a halogen atom or a nitrile group.

[0056] According to the invention, aryl or heteroaryl refers in particular to radicals derived from phenyl, naphthyl, anthracenyl, benzanthryl, phenanthrenyl, pyrenyl, phenyl, benzopyrenyl, biphenyl, phenylene, terphenyl, triphenyl, tetraphenyl, fluorenyl, spirobifluorenyl, dihydrophenanthrenyl, triphenylene, dihydropyrenyl, tetrahydropyrenyl, cis- or trans-indenofluorenyl, cis- or trans-indenocarbazolyl, cis- or trans-indolocarbazolyl, trimerized indenyl, isotrimerized indenyl, spirotrimerized indenyl, spiroisotrimerized indenyl, furyl, benzofuranyl, isobenzofuranyl, dibenzofuranyl, thienyl, benzothienyl, isobenzothienyl, dibenzothienyl, pyrrolyl, indole yl, isoindolyl, carbazolyl, pyridinyl, quinolyl, isoquinolyl, acridinyl, phenanthridinyl, benzo[5,6]quinolyl, benzo[6,7]quinolyl, benzo[7,8]quinolyl, phenothiazinyl, phenoxazinyl, pyrazolyl, indazolyl, imidazolyl, benzimidazolyl, naphthoimidazolyl, phenanthroimidazolyl, pyridoimidazolyl, pyrazinoimidazolyl, quinoxalinoimidazolyl, oxazolyl, benzoxazolyl, naphthoxazolyl, anthrazolyl, phenanthroxazolyl, isoxazolyl, 1,2-thiazolyl, 1,3-thiazolyl, benzothiazolyl, pyridazinyl, hexazolyl Azatriphenanthrenyl, benzopyridazinyl, pyrimidinyl, benzopyrimidinyl, quinoxalinyl, 1,5-diazaanthryl, 2,7-diazapyrenyl, 2,3-diazapyrenyl, 1,6-diazapyrenyl, 1,8-diazapyrenyl, 4,5-diazapyrenyl, 4,5,9,10-tetraazaperyl, pyrazinyl, phenazinyl, phenoxazinyl, phenothiazinyl, fluorescein ring group, naphthyridinyl, azacarbazolyl, benzocarbolinyl, carbolinyl, phenanthrolinyl, 1,2,3-triazolyl, 1,2,4-triazolyl, benzotriazolyl, 1,2,3-oxadiazolyl , 1,2,4-oxadiazolyl, 1,2,5-oxadiazolyl, 1,3,4-oxadiazolyl, 1,2,3-thiadiazolyl, 1,2,4-thiadiazolyl, 1,2,5-thiadiazolyl, 1,3,4-thiadiazolyl, 1,3,5-triazinyl, 1,2,4-triazinyl, 1,2,3-triazinyl, tetrazolyl, 1,2,4,5-tetrazinyl, 1,2,3,4-tetrazinyl, 1,2,3,5-tetrazinyl, purinyl, pteridinyl, indolizinyl, quinazolinyl, benzothiadiazolyl or a group derived from a combination of these systems.

[0057] "Acyl" within the meaning of the present invention refers to a substituted carbonyl group (COR).

[0058] An "ester group" within the meaning of the present invention is a substituted oxycarbonyl group (-OCOR or CO2R).

[0059] An "ether group" within the meaning of the present invention is an -OR group.

[0060]

[0014] "Thio" or "thioether" as used herein are used interchangeably and refer to a -SR group.

[0061] "Sulfinyl" within the meaning of this invention is a -SOR group.

[0062] "Sulfonyl" within the meaning of the present invention is a -SO2R group.

[0063] A "phosphino" group within the meaning of the present invention is a -PR3 group, where each R may be identical or different.

[0064] A "silyl group" within the meaning of the present invention is a -SiR3 group, where each R may be identical or different.

[0065] Each of the above R is preferably selected from the group consisting of alkyl, cycloalkyl, aryl, and heteroaryl.

[0066] The aryloxy group used in the present invention refers to R'O - The monovalent functional group represented by is an aryl group having a carbon number of 6 to 60. Non-limiting examples of such an aryloxy group include phenoxy, naphthyloxy, biphenyloxy and the like.

[0067] The alkylsilyl group used in the present invention refers to a silyl group substituted by an alkyl group having 1 to 40 carbon atoms, wherein the number of carbon atoms constituting the alkylsilyl group is at least 3. Non-limiting examples of the alkylsilyl group include trimethylsilyl and triethylsilyl. The arylsilyl group refers to a silyl group substituted by an aryl group having 6 to 60 carbon atoms.

[0068] The arylphosphino group used in the present invention refers to a diarylphosphino group substituted with an aryl group having 6 to 60 carbon atoms. Non-limiting examples of arylphosphino groups include diphenylphosphino and bis(4-trimethylsilylphenyl)phosphino. An aryloxyphosphino group is a diarylphosphino group in which the phosphorus atom is oxidized to its highest valence state.

[0069] The arylboryl group used in the present invention refers to a diarylboryl group substituted with an aryl group having 6 to 60 carbon atoms. Non-limiting examples of the arylboryl group include diphenylboryl and di(2,4,6-trimethylphenyl)boryl. The alkylboryl group refers to a dialkylboryl group substituted with an alkyl group having 1 to 40 carbon atoms. Non-limiting examples of the alkylboryl group include di-tert-butylboryl and diisobutylboryl.

[0070] "Halo", "halogen", "halogen atom", "halo" in the sense of the present invention are used interchangeably and refer to fluorine, chlorine, bromine or iodine.

[0071] As used herein, "a combination thereof" or "a group thereof" means that one or more members of an applicable list are combined to form a known or chemically stable arrangement that one of ordinary skill in the art can conceive from the applicable list. For example, an alkyl group and a deuterium group can be combined to form a partially or fully deuterated alkyl group; a halogen and an alkyl group can be combined to form a haloalkyl substituent, such as a trifluoromethyl group; and a halogen, an alkyl group, and an aryl group can be combined to form a haloaralkyl group.

[0072] In the present invention, the term "substituted or unsubstituted" means a group selected from hydrogen, deuterium, a halogen atom, a hydroxyl group, a nitrile group, a nitro group, an amino group, an amidine group, a hydrazine group, a hydrazone group, a carboxyl group or a carboxylate thereof, a sulfonic acid group or a sulfonate thereof, a phosphoric acid group or a phosphate thereof, a C1-C 40 Alkyl, C2-C 40 Alkenyl, C2-C 40 Alkynyl, C1-C 40 Alkoxy, C3-C 40 Cycloalkyl, C3-C 40 Cycloalkenyl, C6-C 60 Aryl, C6-C 60 Aryloxy, C6-C 60 Aryl sulfide group and C2-C 60 The heteroaryl group may be substituted or unsubstituted with one or more substituents, or may be substituted or unsubstituted with a substituent formed by linking two or more of the substituents exemplified above.

[0073] In one example, the term substituted includes combinations of two to four of the listed groups.

[0074] In another example, the term substitution includes a combination of two to three groups. In yet another example, the term substitution includes a combination of two groups. A preferred combination of substituents is a combination containing up to fifty atoms that are not hydrogen or deuterium, or a combination including up to forty atoms that are not hydrogen or deuterium, or a combination including up to thirty atoms that are not hydrogen or deuterium. In many cases, a preferred combination of substituents will include up to twenty atoms that are not hydrogen or deuterium.

[0075] According to an embodiment of the present invention, the metal complex is selected from the group consisting of:

[0076]

[0077]

[0078]

[0079]

[0080]

[0081]

[0082]

[0083]

[0084]

[0085]

[0086]

[0087] Some or all of the hydrogen atoms in the above structure may be replaced by deuterium atoms.

[0088] An application of the organic electroluminescent material in an organic electroluminescent device.

[0089] The organic electroluminescent device of the present invention can obtain blue light with high luminous efficiency.

[0090] An organic electroluminescent device comprises an anode, a cathode and at least one organic layer disposed between the anode and the cathode, wherein the organic layer comprises a metal complex of formula (I).

[0091] The organic layer of the present invention may be an emissive layer and the metal complex as described herein may be an emissive dopant or a non-emissive dopant.

[0092] Furthermore, the organic layer may further comprise a host material and a dopant, wherein the dopant comprises a metal complex of formula (I).

[0093] The organic electroluminescent material may be a sensitizer; wherein the device may further comprise an acceptor, a fluorescent emitter, a delayed fluorescent emitter, and combinations thereof.

[0094] The organic electroluminescent device of the present invention may further comprise an emission region, wherein the emission region comprises a compound as disclosed in the above compound section of the present disclosure.

[0095] Furthermore, the host material is selected from the group consisting of triphenylene, carbazole, indolecarbazole, dibenzothiophene, dibenzofuran, fluorene, dibenzoselenophene, 5,9-dioxa-13b-boronaphtho[3,2,1-de]anthracene, aza-triphenylene, aza-carbazole, aza-indolecarbazole, aza-dibenzothiophene, aza-dibenzofuran, aza-dibenzoselenophene and aza-(5,9-diaza-13b-boronaphtho[3,2,1-de]anthracene) or a group derived from a combination of these systems.

[0096] Preferably, the host material is selected from the group consisting of the following structures:

[0097]

[0098]

[0099] The materials described herein as suitable for use in a particular layer of an organic light-emitting device can be used in combination with a variety of other materials present in the device. For example, the emissive dopants disclosed herein can be used in combination with a wide variety of hosts, transport layers, barrier layers, injection layers, electrodes, and other layers that may be present. The materials described or mentioned below are non-limiting examples of materials that can be used in combination with the compounds disclosed herein, and those skilled in the art can readily consult the literature to identify other materials that can be used in combination.

[0100] The mass ratio of the main material to the doping material is 99:1 to 1:99.

[0101] Preferably, the mass ratio of the host material to the doping material is 98:2 to 50:50.

[0102] Furthermore, the mass ratio of the main material to the doping material is 98:2 to 90:10.

[0103] These processes are generally known to those skilled in the art and they can apply them without inventive step to organic electroluminescent devices comprising the compounds according to the invention.

[0104] According to one embodiment, novel ligands for metal complexes are disclosed. The inventors have discovered that the introduction of these ligands unexpectedly narrows the emission spectrum, lowers the sublimation temperature, and improves the luminous efficiency of the device.

[0105] The following preparation methods can be cited as the preparation methods of the organic electroluminescent device of the present invention, but are not limited thereto. A person skilled in the art can make various modifications based on the common technical knowledge in the art. The above-mentioned preparation method includes the following steps:

[0106] Cleaning process: Use detergent, deionized water, organic solvent, etc. to clean the glass substrate with ITO;

[0107] a step of forming a hole injection layer by vacuum evaporating a hole injection layer-forming material containing the organic electroluminescent material of the present invention on the aforementioned anode layer, thereby forming a hole injection layer containing the organic electroluminescent material of the present invention on the aforementioned substrate;

[0108] forming a hole transport layer by vacuum evaporation to form a hole transport layer on the hole injection layer;

[0109] A step of forming an organic light-emitting layer: vacuum-depositing an organic light-emitting layer-forming material comprising the material of the present invention on the aforementioned hole transport layer to form an organic light-emitting layer comprising the organic electroluminescent material of the present invention on the aforementioned hole transport layer;

[0110] A step of forming an electron transport layer: vacuum-depositing an electron transport layer-forming material containing the organic electroluminescent material of the present invention on the organic light-emitting layer, thereby forming an electron transport layer containing the organic electroluminescent material of the present invention on the organic light-emitting layer;

[0111] Step of forming a cathode layer: evaporating, sputtering or spin-coating a cathode forming material on the electron transport layer to form a cathode layer.

[0112] A consumer product comprising the organic electroluminescent device.

[0113] The consumer product of the present invention can be one of the following products: a flat panel display, a computer monitor, a medical monitor, a television, a sign, a light for interior or exterior lighting and / or signaling, a head-up display, a fully or partially transparent display, a flexible display, a laser printer, a telephone, a cellular telephone, a tablet computer, a phablet, a personal digital assistant (PDA), a wearable device, a laptop computer, a digital camera, a video camera, a viewfinder, a microdisplay having a diagonal of less than 2 inches, a 3-D display, a virtual reality or augmented reality display, a vehicle, a video wall comprising multiple displays tiled together, a theater or stadium screen, a light therapy device, and a sign.

[0114] Compared with the prior art, the present invention has the following beneficial effects:

[0115] (1) When the metal complex of the present invention is used in OLEDs, especially in the blue light emitting region, it exhibits enhanced phosphorescence quantum yield, good luminescence stability, and high luminescence efficiency, and is suitable for use as an emitting dopant in OLED applications. The metal complex of the present invention can produce an organic electroluminescent device that emits blue phosphorescent light and has improved luminescence efficiency, and the light-emitting device has good thermal stability. Consumer products containing the organic electroluminescent device of the present invention can produce electronic devices that emit blue phosphorescent light and have improved luminescence efficiency.

[0116] (2) The metal complex described in the present invention regulates its photophysical properties by adjusting the structure of the ligands surrounding the metal center and the structure of the substituents on the ligands. It has the advantages of narrow emission spectrum, high stability and high efficiency, and has broad application prospects in many fields such as OLED displays and lighting. BRIEF DESCRIPTION OF THE DRAWINGS

[0117] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0118] Figure 1 A schematic diagram of an organic light-emitting device 100 is shown. The illustration is not necessarily drawn to scale. Device 100 may include a substrate 101, an anode 102, a hole injection layer 103, a hole transport layer 104, an electron blocking layer 105, a light-emitting layer 106, a hole blocking layer 107, an electron transport layer 108, an electron injection layer 109, a cathode 110, and a capping layer (CPL) 111. Device 100 can be fabricated by depositing the described layers in order.

[0119] Figure 2 A schematic diagram of an organic light-emitting device 200 showing two light-emitting layers. The device includes a substrate 201, an anode 202, a hole injection layer 203, a hole transport layer 204, a first light-emitting layer 205, an electron transport layer 206, a charge generation layer 207, a hole injection layer 208, a hole transport layer 209, a second light-emitting layer 210, an electron transport layer 211, an electron injection layer 212, and a cathode 213. Device 200 can be fabricated by sequentially depositing the described layers. While most common OLED devices have a single light-emitting layer, device 200 has a first light-emitting layer and a second light-emitting layer. The emission peaks of the first and second light-emitting layers can overlap, overlap, or not overlap. Materials similar to those described for device 100 can be used in the corresponding layers of device 200. Figure 2One example is provided of how some layers may be added from the structure of device 100 . DETAILED DESCRIPTION

[0120] To make the objectives, technical solutions, and advantages of the present invention more apparent, the technical solutions of the present invention will be described in detail below. Obviously, the embodiments described are only some of the embodiments of the present invention, not all of them. Based on the embodiments of the present invention, all other implementations obtained by those of ordinary skill in the art without inventive effort are within the scope of protection of the present invention.

[0121] The "EQE" in the present invention refers to the external quantum efficiency of a device, that is, the ratio of the number of photons emitted by the device to the number of electrons injected into the device.

[0122] The organic electroluminescent device described in the present invention comprises at least one organic layer disposed between an anode and a cathode and electrically connected to the anode and the cathode. Figure 1 A schematic diagram of an organic light-emitting device 100 is shown. The illustration is not necessarily drawn to scale. Device 100 may include a substrate 101, an anode 102, a hole injection layer 103, a hole transport layer 104, an electron blocking layer 105, a light-emitting layer 106, a hole blocking layer 107, an electron transport layer 108, an electron injection layer 109, a cathode 110, and a capping layer (CPL) 111. Device 100 can be fabricated by depositing the described layers in order.

[0123] Figure 2 A schematic diagram of an organic light-emitting device 200 containing two light-emitting layers is shown. The device includes a substrate 201, an anode 202, a hole injection layer 203, a hole transport layer 204, a first light-emitting layer 205, an electron transport layer 206, a charge generation layer 207, a hole injection layer 208, a hole transport layer 209, a second light-emitting layer 210, an electron transport layer 211, an electron injection layer 212, and a cathode 213. Device 200 can be fabricated by sequentially depositing the described layers. While most common OLED devices have a single monochromatic light-emitting layer or light-emitting layers of three primary colors, device 200 has two light-emitting layers of the same color. Materials similar to those described for device 100 can be used in the corresponding layers of device 200. Figure 2 One example is provided of how some layers may be added from the structure of device 100 .

[0124] Figure 1 and Figure 2The simple layered structure illustrated in is provided as a non-limiting example, and it will be understood that embodiments of the invention may be used in conjunction with a wide variety of other structures. The specific materials and structures described are exemplary in nature, and other materials and structures may be used. Functional OLEDs may be achieved by combining the various layers described in different ways, or several layers may be omitted entirely, based on design, performance, and cost factors. Other layers not specifically described may also be included. Materials different from those specifically described may be used. Although many of the examples provided herein describe the various layers as comprising a single material, it will be understood that combinations of materials may be used, such as a mixture of a host and a dopant, or more generally, a mixture. Also, the layers may have various sub-layers. The names given to the various layers herein are not intended to be strictly limiting. For example, in device 200, hole transport layer 204 transports holes and injects holes into light-emitting layer 205, and may be described as a hole transport layer or an electron blocking layer. In one embodiment, the OLED may be described as having an organic layer disposed between a cathode and an anode. This organic layer may comprise a single layer or may further comprise, for example Figure 1 and Figure 2 Multiple layers of different organic materials are described.

[0125] Structures and materials not specifically described may also be used, such as PLEDs comprising polymeric materials. As another example, an OLED having a single organic layer or a stack of multiple layers may be used. The OLED structure may be separated from Figure 1 and Figure 2 For example, the substrate may include angled reflective surfaces to improve light coupling.

[0126] Unless otherwise specified, any of the layers of the various embodiments may be deposited by any suitable method. For organic layers, preferred methods include thermal evaporation, organic vapor deposition methods, or applying one or more layers with the aid of carrier gas sublimation, wherein the layers are deposited at 10 -5 The material is applied at a pressure between mbar and 1 bar. A particular example of this method is the organic vapor jet printing method, in which the material is applied directly through a nozzle and is therefore structured. Other suitable deposition methods include, for example, spin coating, or by means of any desired printing method such as screen printing, flexographic printing, lithography, photoinduced thermography, thermal transfer, inkjet printing or nozzle printing, to produce one or more layers. Soluble compounds, for example, can be obtained by appropriate substitution. These methods are also particularly suitable for oligomers, dendrimers and polymers. Also feasible are hybrid methods, in which, for example, one or more layers are applied from solution and one or more additional layers are applied by vapor deposition.

[0127] Devices manufactured according to embodiments of the present invention may further optionally include a barrier layer. One purpose of the barrier layer is to protect the electrodes and organic layers from damage due to exposure to harmful substances in the environment, including moisture, vapor and / or gas. The barrier layer may be deposited on the substrate, the electrode, under the substrate, the electrode, or next to the substrate, the electrode, or on any other part of the device, including the edge. The barrier layer may include a single layer or multiple layers. The barrier layer can be formed by various known chemical vapor deposition techniques and may include compositions having a single phase as well as compositions having multiple phases. Any suitable material or combination of materials can be used for the barrier layer. The barrier layer may incorporate inorganic or organic compounds or both. Preferably, the barrier layer includes a mixture of a polymeric material and a non-polymeric material. In order to be considered a mixture, the aforementioned polymer and non-polymeric materials that make up the barrier layer should be deposited under the same conditions and / or at the same time. The weight ratio of the polymeric material to the non-polymeric material may be in the range of 95 / 5 to 5 / 95. In one example, the mixture of the polymeric material and the non-polymeric material essentially consists of polymeric silicon and inorganic silicon.

[0128] In any of the above-mentioned compounds used in each layer of the OLED device, the hydrogen atoms may be partially or fully deuterated. Thus, any of the specifically listed substituents, such as (but not limited to) methyl, phenyl, pyridyl, etc., may be in their non-deuterated, partially deuterated, and fully deuterated forms. Similarly, substituent groups (such as (but not limited to) alkyl, aryl, cycloalkyl, heteroaryl, etc.) may also be in their non-deuterated, partially deuterated, and fully deuterated forms.

[0129] The materials and structures described herein can be applied to devices other than OLEDs. For example, other optoelectronic devices such as organic solar cells and organic photodetectors can use the materials and structures.

[0130] Furthermore, organic devices such as organic transistors may utilize the materials and structures.

[0131] In the following examples of the present invention, conventional preparation methods were used unless otherwise specified. Raw materials used were obtained from public commercial sources unless otherwise specified, and percentages are by mass unless otherwise specified.

[0132] In order to explain the present invention more clearly, the technical solution of the present invention is described below with reference to some specific embodiments:

[0133] In the embodiment of the present invention, the performance testing conditions of the prepared electroluminescent device are as follows:

[0134] Chromaticity coordinates: tested using a spectrum scanner PhotoResearch PR-715;

[0135] Current-voltage: Tested using a Keithley 2420 digital source meter;

[0136] Power efficiency: tested using NEWPORT 1931-C;

[0137] Brightness: tested using a Minolta CS-1000A brightness meter.

[0138] Example 1

[0139] The preparation method of the metal complex P5 comprises the following steps:

[0140] Step 1: Preparation of compound Int-1

[0141]

[0142] Under nitrogen protection, 25.0 mmol of S1 was dissolved in 60 mL of toluene, 30 mL of ethanol and 30 mL of water, and 75.0 mmol of anhydrous sodium carbonate and 5.0 mmol of tetrabutylammonium bromide were added, followed by 30.0 mmol of S2 and 0.01 mmol of Pd132. The temperature was raised to reflux and stirred for 15 hours. The temperature was cooled to room temperature, and 50 mL of ethyl acetate and 50 mL of water were added and stirred to dissolve. The organic phase was collected, dried, filtered, and the filtrate was concentrated to dryness. The intermediate Int-1 was separated and purified by silica gel column to obtain a yellow solid with a yield of 76%.

[0143] Step 2: Preparation of compound Int-2

[0144]

[0145] Under nitrogen protection, 20.0 mmol of Int-1 was dissolved in 60 mL of DMF, and then 30.0 mmol of S3, 60.0 mmol of anhydrous potassium carbonate, 3.0 mmol of cuprous iodide and 6.0 mmol of N,N-dimethylglycine were added. The temperature was raised to 120°C and stirred for 12 hours. The temperature was cooled to room temperature, and the reaction solution was poured into 200 mL of water and filtered. The filter cake was washed with water, dried, and separated and purified on a silica gel column to obtain a yellow solid Int-2 with a yield of 87%.

[0146] Step 3: Preparation of compound Int-3

[0147]

[0148] Under nitrogen protection, 10.0 mmol of Int-2 prepared in the previous step and 100 mL of dry chlorobenzene were mixed, and 20.0 mmol of boron tribromide was slowly added dropwise. The mixture was stirred and reacted for 1 hour, and then 0.1 mol of triethylamine was added dropwise. The temperature was raised to 150°C and stirred for 15 hours. The mixture was cooled to room temperature, concentrated and dried under reduced pressure, and purified by silica gel column to obtain compound Int-3 as a yellow solid in a yield of 65%.

[0149] Step 4: Preparation of compound Int-4

[0150]

[0151] Under nitrogen protection, 10.0 mmol of Int-3 was dissolved in 50 mL of DMF, and 22.0 mmol of S4 (diphenyliodonium trifluoromethanesulfonate) and 0.4 mmol of anhydrous copper acetate were added. The temperature was raised to reflux and stirred for 2 hours. The temperature was cooled to room temperature and filtered. The filtrate was poured into 150 mL of ice water and filtered. The filter cake was washed with water and ethanol to obtain a yellow solid Int-4 with a yield of 75%.

[0152] Step 5: Preparation of compound P5

[0153]

[0154] Under nitrogen, 15.0 mmol of Int-4 was dissolved in 200 mL of DMF. 15.0 mmol of Pt(COD)Cl2 and 45.0 mmol of sodium acetate were added. The mixture was stirred and heated to reflux for 15 hours. The mixture was cooled to room temperature and concentrated under reduced pressure to dryness. Dichloromethane was added for dissolution. The organic phase was collected, washed with water, dried, and filtered. The filtrate was concentrated under reduced pressure to dryness and purified on a silica gel column to obtain compound P5 as a yellow solid in a 53% yield. HRMS (MALDI-TOF): Calcd: 951.26, Found: 952.26 [M+H].

[0155] Example 2

[0156] The preparation method of the metal complex P59 comprises the following steps:

[0157] Step 1: Preparation of compound Int-5

[0158]

[0159] Under nitrogen protection, 25.0 mmol of S5 was dissolved in 60 mL of acetonitrile and 30 mL of water, and 50.0 mmol of anhydrous sodium carbonate and 5.0 mmol of tetrabutylammonium bromide were added, followed by 30.0 mmol of phenylboric acid and 0.01 mmol of Pd(PPh3)4. The temperature was raised to reflux and stirred for 15 hours. The temperature was then cooled to room temperature, and 50 mL of ethyl acetate and 50 mL of water were added and stirred to dissolve. The organic phase was separated, and the aqueous phase was extracted with ethyl acetate. The organic phase was collected, washed with saturated brine, dried, filtered, and the filtrate was concentrated to dryness. The intermediate Int-5 was obtained as a yellow solid with a yield of 77%.

[0160] Step 2: Preparation of compound Int-6

[0161]

[0162] Referring to the synthesis method of the second step of Example 1, compound Int-1 in the second step of Example 1 was replaced by Int-5, and S3 in the second step of Example 1 was replaced by S6 to prepare compound Int-6 with a yield of 82%.

[0163] Step 3: Preparation of compound Int-7

[0164]

[0165] Under nitrogen protection, 10.0 mmol of Int-6 prepared in the previous step and 100 mL of dry o-dichlorobenzene were mixed, and 22.0 mmol of boron tribromide was slowly added dropwise. The mixture was stirred for 1 hour, and then 0.1 mol of triethylamine was added dropwise. The temperature was raised to 150°C and stirred for 15 hours. The mixture was cooled to room temperature, and the reaction solution was poured into 200 mL of ethanol and filtered. The filter cake was washed with ethanol, and the solid was separated and purified by silica gel column to obtain compound Int-7 as a yellow solid with a yield of 54%.

[0166] Step 4: Preparation of compound P59

[0167]

[0168] Under nitrogen, 15.0 mmol of Int-7 was dissolved in 100 mL of acetic acid. 16.5 mmol of KPtCl and 1.5 mmol of tetrabutylammonium bromide were added, and the mixture was stirred and heated to reflux for 15 hours. The mixture was cooled to room temperature and concentrated under reduced pressure to dryness. The mixture was extracted with dichloromethane and filtered. The filtrate was concentrated under reduced pressure to dryness and purified on a silica gel column to obtain compound P59 as a yellow solid in a 51% yield. HRMS (MALDI-TOF): Calcd: 934.19, Found: 935.19 [M+H].

[0169] Example 3

[0170] The preparation of the metal complex P133 comprises the following steps:

[0171] Step 1: Preparation of compound Int-9

[0172]

[0173] Under nitrogen protection, 10.0 mmol of Int-8 (prepared according to the synthetic method of Example 1) and 100 mL of dry chlorobenzene were mixed, and 12.0 mmol of boron tribromide was slowly added dropwise. The mixture was stirred and reacted for 1 hour, and then 0.1 mol of diisopropylethylamine was added dropwise. The temperature was raised to 150°C and stirred for 15 hours. After cooling to room temperature, the reaction solution was poured into 200 mL of ethanol and filtered. The filter cake was washed with ethanol, and the solid was separated and purified by silica gel column to obtain compound Int-9 as a yellow solid with a yield of 83%.

[0174] Step 2: Preparation of compound P133

[0175]

[0176] Referring to the synthesis method of the fourth step of Example 2, only the compound Int-7 in the fourth step of Example 2 was replaced by Int-9 to prepare compound P133. The yield was 58%. HRMS (MALDI-TOF): calculated value: 973.20, found value: 974.21 [M+H].

[0177] Example 4

[0178] The preparation of metal complex P224 comprises the following steps:

[0179] Step 1: Preparation of compound Int-11

[0180]

[0181] Under nitrogen protection, 22.0 mmol of Int-10 (prepared by the synthetic method according to Example 1) and 60 mL of dry xylene were mixed, and then 20.0 mmol of S7, 30.0 mmol of sodium tert-butoxide, 0.2 mmol of Pd2(dba)3 and 0.5 mmol of 10% tri-tert-butylphosphine toluene solution were added. The temperature was raised to 110°C and stirred for 15 hours. After cooling to room temperature, 100 mL of 2M dilute hydrochloric acid aqueous solution was added, the organic phase was separated, and the aqueous phase was extracted with dichloromethane. The organic phases were combined, dried, filtered, and the filtrate was concentrated under reduced pressure and purified by silica gel column to obtain compound Int-11 as a yellow solid with a yield of 87%.

[0182] Step 2: Preparation of compound Int-12

[0183]

[0184] Referring to the synthesis method of the first step of Example 3, only replacing compound Int-8 in the first step of Example 3 with Int-11, compound Int-12 was prepared with a yield of 85%.

[0185] Step 3: Preparation of compound P224

[0186]

[0187] Referring to the synthesis method of the fourth step of Example 2, only replacing compound Int-7 in the fourth step of Example 2 with Int-12, compound P224 was prepared with a yield of 56%. HRMS (MALDI-TOF): calculated value: 957.21, found value: 958.21 [M+H].

[0188] Example 5

[0189] The preparation of the metal complex P303 comprises the following steps:

[0190] Step 1: Preparation of compound Int-14

[0191]

[0192] Under nitrogen protection, 10.0 mmol of Int-13 (prepared by the synthetic method according to Example 1) and 80 mL of dry tert-butylbenzene were mixed, cooled to -78°C, and 20.0 mmol of 1.7 M tert-butyllithium pentane solution was added dropwise. The temperature was raised to 50°C and stirred for reaction for 1 hour. The temperature was then lowered to -78°C, and 20.0 mmol of boron triiodide was added dropwise. The temperature was stirred for reaction for 1 hour. Then 50.0 mmol of diisopropylethylamine was added dropwise. The temperature was raised to 150°C, and the temperature was stirred for reaction for 48 hours. The mixture was cooled to room temperature, concentrated under reduced pressure, and purified by silica gel column to obtain compound Int-14 as a yellow solid with a yield of 37%.

[0193] Step 2: Preparation of compound P303

[0194]

[0195] Referring to the synthesis method of the fourth step of Example 2, only the compound Int-7 in the fourth step of Example 2 was replaced by Int-14 to prepare compound P303. The yield was 52%. HRMS (MALDI-TOF): calculated value: 934.19, found value: 935.19 [M+H].

[0196] Example 6 to Example 312

[0197] The following compounds were prepared by similar synthetic methods to those in the above examples:

[0198]

[0199]

[0200]

[0201]

[0202]

[0203]

[0204]

[0205]

[0206]

[0207]

[0208]

[0209]

[0210]

[0211]

[0212]

[0213]

[0214]

[0215]

[0216]

[0217]

[0218]

[0219]

[0220]

[0221]

[0222]

[0223]

[0224]

[0225]

[0226]

[0227]

[0228] Preparation of organic electroluminescent devices

[0229] The glass substrate with patterned ITO electrodes was ultrasonically treated in a cleaning agent for 30 minutes, rinsed in deionized water, ultrasonically treated in an acetone / ethanol mixed solvent for 30 minutes, baked in a clean environment until completely dry, irradiated with an ultraviolet light cleaner for 10 minutes, and bombarded with a low-energy cation beam.

[0230] Place the treated ITO glass substrate in a vacuum chamber and evacuate to a temperature less than 1×10 -5 Pa, metallic silver is evaporated on the above ITO film as the anode, and the thickness of the evaporated film is Continue to evaporate the compound HATCN as the hole injection layer, and the evaporated film thickness is HTM is continuously evaporated on the hole injection layer to form a hole transport layer with a thickness of

[0231] BPrime was evaporated on the hole transport layer as an electron blocking layer with a thickness of

[0232] The metal complex of the present invention and PH022 are evaporated on the above electron blocking layer as the organic light-emitting layer of the device, wherein PH022 is the main material and the metal complex of the present invention is the doping material, the doping concentration is 3%, and the evaporated film thickness is

[0233] A layer of compound DPO is further evaporated on the organic light-emitting layer as the hole blocking layer of the device. The thickness of the evaporated film is

[0234] On the hole blocking layer, a layer of LiQ and ET318 is further evaporated as the electron transport layer of the device, wherein LiQ is 50% of the mass of ET318 and the thickness of the evaporated film is

[0235] A layer of LiF is continuously evaporated on the above electron transport layer as the electron injection layer of the device, and the thickness of the evaporated film is

[0236] On the electron injection layer, magnesium and silver are evaporated as the cathode layer of the device, wherein the mass ratio of magnesium to silver is 1:10 and the thickness of the evaporated film is

[0237] Finally, the compound HTM is evaporated on the cathode layer as a capping layer with a thickness of To prepare the organic electroluminescent element of the present invention, Figure 1 device 100.

[0238] Comparative Example 1

[0239] Comparative device 1 was prepared by using the compound shown in BD015 instead of the metal complex of the organic electroluminescent device and following the same other steps as above.

[0240] The structural formulas of the aforementioned HATCN, HTM, BPrime, PH022, BD015, DPO, and ET318 are as follows:

[0241]

[0242] Example 313

[0243] According to the same steps as those for preparing the organic electroluminescent device, the metal complex contained in the organic electroluminescent material of the present invention is used instead of the metal complex of the organic electroluminescent device to manufacture an organic electroluminescent element. The driving voltage and current efficiency of the light-emitting element and the life of the element are measured using a digital source meter and a luminance meter. Specifically, the voltage is increased at a rate of 0.1 V per second, and the current density of the organic electroluminescent element is measured when it reaches 10 mA / cm 2 The voltage at this time is the driving voltage, and the brightness at this time is measured at the same time; the ratio of brightness to current density is the current efficiency; the LT95% life test is as follows: use a luminance meter at 1000cd / m 2 Under the same brightness, the current is kept constant and the brightness decay of the organic electroluminescent element is measured to be 950cd / m 2 The time is in hours. Some of the results are summarized in Table 1. *The data are normalized compared with the comparative element 1.

[0244] Table 1

[0245]

[0246]

[0247]

[0248]

[0249]

[0250]

[0251]

[0252] As can be seen from Table 1, the organic electroluminescent element prepared using the metal complex of the present invention has a lower driving voltage, a higher external quantum emission efficiency, an excellent lifespan, and good color purity compared to the comparative element 1, and is an organic electroluminescent material with excellent performance.

[0253] The metal complex BD015 in Comparative Element 1 differs from the metal complex of the present invention in that the metal complex of the present invention incorporates boron-nitrogen or boron-oxygen into the metal-to-ligand charge transfer group of C^Pt or N^Pt, leveraging the boron-nitrogen or boron-oxygen conjugation effect to achieve the TADF effect while simultaneously reducing the degree of excited-state relaxation. This results in high efficiency and a darker blue luminescence color. However, the ligand of the metal complex BD015, which uses a five-membered triazole as its parent nucleus, solely utilizes metal-to-ligand charge transfer to achieve triplet phosphorescence. This metal complex exhibits low stability, resulting in high driving voltage, low efficiency, and a device with a LT95% lifetime inferior to the excellent performance of the metal complex of the present invention as a dopant material for the light-emitting layer.

[0254] The foregoing is merely a representative example of a specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any modifications or substitutions that can be readily conceived by a person skilled in the art within the technical scope disclosed herein are intended to be encompassed by the scope of protection of the present invention. Therefore, the scope of protection of the present invention shall be subject to the scope of protection of the claims.

Claims

1. A metal complex, characterized in that The metal complex is selected from the group consisting of: 、 、 、 、 、 、 、 、 、 、 、 、 、 、 、 ； in, The L 1 , L 2 Each independently selected from a single bond, O, S, NR 8 or CR 8 R 9 ; the R 1 、R 2 、R 3 、R 4 、R 5 、R 6 、R 7 、R 8 、R 9 Each independently selected from a hydrogen atom, R A1 、R A3 、R B1 、R B83 、R B186 、R B156 、R C1 or R C2 the groups formed; Among them, R A1 、R A3 The structural formula is shown below: 、 ； R B1 、R B83 、R B186 、R B156 The structure shown is as follows: 、 、 、 ； R C1 、R C2 The structure shown is as follows: 、 。 2. A metal complex, characterized in that The metal complex is selected from the group consisting of: ; Among them, R B1 、R B3 、R B156 、R B186 、R C1 、R C2 The structures are: 、 、 、 、 、 。 3. An organic electroluminescent device, comprising an anode, a cathode, and at least one organic layer disposed between the anode and the cathode, wherein the organic layer comprises the metal complex according to any one of claims 1 or 2.

4. The organic electroluminescent device according to claim 3, wherein: The organic layer further comprises a host material and a doping material, and the doping material comprises the metal complex according to any one of claims 1 or 2.

5. The organic electroluminescent device according to claim 4, wherein: The host material is selected from the group consisting of the following structures:

6. The organic electroluminescent device according to claim 5, wherein: The mass ratio of the main material to the doping material is 99:1 to 1:99.

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