A carbene currency metal complex and preparation and application thereof

Abstract

The application discloses a carbene currency metal complex and preparation and application thereof, and belongs to the technical field of electroluminescent materials.The complex structure features of the application are that a monovalent currency metal is taken as a core, and a cyclic alkyl amino carbene ligand and a carbazole ligand with a five-membered ring side wing group are connected respectively.The carbene ligand with the five-membered ring side wing group in the complex has the characteristics of simple and efficient synthesis and cheap and easily available raw materials, and can solve the current design problem of the carbene ligand.In addition, the carbene currency metal complex has the characteristics of thermal activation delayed fluorescence, and has the advantages of high photo-induced quantum yield, short exciton lifetime and high efficient device performance, and provides a new scheme for constructing an organic electroluminescent device with high efficiency and low cost.

Description

Technical Field

[0001] This invention relates to the field of electroluminescent materials technology, and in particular to a carbene coin metal complex and its preparation and application. Background Technology

[0002] Organic light-emitting diodes (OLEDs) have attracted significant attention and are increasingly being implemented in commercial applications due to their advantages such as low driving voltage, low power consumption, flexible display, fast response, wide viewing angle, and high processability. To date, OLED devices typically employ a multi-layered structure, including a glass substrate, anode, hole injection layer, hole transport layer, emissive layer, electron transport layer, electron injection layer, and cathode. Among these, the emissive layer plays a crucial role. Therefore, improving the luminous efficiency of the emissive layer material is currently a key research focus.

[0003] Existing luminescent layer materials are mainly divided into three types: traditional fluorescent materials, heavy metal phosphorescent materials, and organic thermally activated delayed fluorescence materials. Traditional fluorescent materials can only utilize singlet excitons to emit fluorescence, thus their devices have an external quantum efficiency of up to 5%. In contrast, heavy metal phosphorescent materials and organic thermally activated delayed fluorescence materials can both utilize triplet excitons, greatly improving exciton utilization and thus significantly increasing device efficiency. Phosphorescent materials utilize triplet excitons by introducing noble metals such as iridium and platinum to enhance the spin-orbit coupling (SOC) between singlet and triplet states. However, the scarcity of these noble metal materials has long been considered a bottleneck limiting the widespread application of phosphorescent OLEDs. Therefore, pure organic thermally activated delayed fluorescence materials that can still utilize triplet excitons without heavy metals have emerged. These materials can achieve a reverse intersystem crossing process from triplet excitons to singlet excitons through ambient thermal energy, and finally emit delayed fluorescence through singlet radiation. However, due to the SOC effect of the lack of metal atoms, the spin-forbidden reverse system crossing (RISC) rate in pure organic TADF molecules is slow, resulting in a long exciton lifetime. Under electroluminescence, this makes them prone to various forms of exciton annihilation, which adversely affects device stability. Therefore, developing a low-cost, high-exciton-utilization, and short-exciton-lifetime luminescent material is particularly important.

[0004] Studies have shown that introducing abundant and inexpensive transition metals into purely organic thermally activated delayed fluorescence (TADF) materials can leverage the heavy atom effect of metals to promote the RISC process, effectively improving TADF luminescence efficiency and shortening TADF fluorescence lifetime. This is beneficial for fabricating high-efficiency, low-roll-off, and relatively inexpensive OLED devices. In 2017, Credgington et al. (D. Credgington, Science, Vol 356, 159, 2017) reported a series of linear carbene-money metal complexes based on monovalent monetary metals. These complexes possess separated frontier orbitals and strong state of charge (SOC), thus achieving thermally activated delayed fluorescence while significantly shortening their TADF lifetime. In the following years, based on the carbene-metal-aromatic amine molecular framework, by adjusting the electron-donating and accepting capabilities of carbene and aromatic amine ligands, full color coverage and high external quantum efficiency (>20%) OLED devices with these complexes were achieved. This makes carbene-money metal complexes with monovalent monetary metals as the core a promising next-generation OLED luminescent material. However, currently, blue carbene currency metal complexes mainly employ cyclic alkyl-amino-carbene ligands, and only carbene currency metal complexes constructed with adamantane or sterically hindered cyclohexane as flanking groups can achieve excellent device efficiency. However, carbene ligands containing these flanking groups suffer from drawbacks such as high raw material costs and difficult synthesis. Therefore, developing a cyclic alkyl-amino-carbene ligand that is readily available and simple to synthesize is of great significance for constructing blue carbene currency metal complexes and their OLED devices.

[0005] Based on the above background and existing technologies, solutions for materials design still need improvement and breakthroughs. Summary of the Invention

[0006] In view of the above-mentioned deficiencies of the prior art, in a first aspect of the present invention, a carbene currency metal complex is provided, wherein the carbene currency metal complex has a monovalent currency metal as its core and is respectively connected to a cyclic alkylamino carbene ligand and a carbazole ligand modified with a five-membered ring sidewall, and its structural formula is as follows:

[0007]

[0008] Where M represents a monovalent monetary metal, A represents a cyclic alkylamino carbene ligand modified with a five-membered ring flanking, B represents a carbazole ligand, and R represents a sterically hindered group.

[0009] Preferably, the monovalent monetary metal is one of copper, silver, and gold, corresponding to compounds with the following structural formulas:

[0010]

[0011] Preferably, the steric hindrance group includes one of phenyl, 2,6-diisopropylphenyl, 2,6-diisophenylphenyl, 2,4,6-trimethylphenyl, adamantyl, methyl, ethyl, isopropyl, and tert-butyl.

[0012] Preferably, the cyclic alkylamino carbene ligand modified with five-membered ring sidewalls comprises one of the following structures:

[0013]

[0014] Z1, Z2, and Z3 are selected from one of hydrogen, deuterium, fluorine, chlorine, bromine, iodine, methyl, ethyl, propyl, isopropyl, n-butyl, sec-butyl, tert-butyl, and methoxy, respectively.

[0015] Preferably, the carbazole ligand comprises one of the following structures:

[0016]

[0017]

[0018] Z1 and Z2 are selected from one of the following: oxygen atom, nitrogen atom, sulfur atom, selenium atom, and tellurium atom, respectively.

[0019] P1, P2, and P3 are respectively selected from hydrogen, deuterium, fluorine, chlorine, bromine, iodine, methyl, ethyl, propyl, isopropyl, n-butyl, sec-butyl, tert-butyl, methoxy, dimethylamino, cyano, trifluoromethyl, trimethylsilyl, vinyl, allyl, benzyl, phenyl, naphthyl, anthracene, benzo[a]anthrayl, phenanthryl, benzo[a]phenanthryl, tetraphenylsilyl, tetraphenylcarbonyl, adamantyl, silanefluorenyl, triphenylene, pyrene, cyclohexyl, peryl, fluoranyl, tetraphenyl, pentaphenyl, benzo[a]pyrene, biphenyl, amphylene, terphenyl, triphenyl, tetraphenyl, fluorenyl, spirodifluorenyl, dihydrophenanthryl, dihydropyrene, tetrahydropyrene, cis Indofluorenyl, trans-indofluorenyl, trimerinyl, isotrimericindofluorenyl, spirotrimericindofluorenyl, spiroisotrimericindofluorenyl, furanyl, benzofuranyl, isobenzofuranyl, dibenzofuranyl, thiopheneyl, benzothiopheneyl, isobenzothiopheneyl, dibenzothiopheneyl, pyrroleyl, isoindoleyl, carbazoleyl, indocarbazoleyl, pyridinyl, quinolinyl, isoquinolinyl, acridineyl, phenanthridineyl, benzo-5,6-quinolinyl, benzo-6,7-quinolinyl, benzo-7,8-quinolinyl, pyrazolyl, indazoleyl, imidazolyl, benzimidazoleyl, naphthiazoleyl, phenanthreneazoleyl, pyridinazoleyl, pyrazinazoleyl, quinoxalinazoleyl, Enoxazolyl, benzoxazolyl, naphthoxazolyl, anthraxazolyl, phenanthrenexazolyl, 1,2-thiazolyl, 1,3-thiazolyl, benzothiazolyl, pyridazinyl, benzopyridazinyl, pyrimidinyl, benzopyrimidinyl, quinoxalinyl, 1,5-diazaanthrayl, 2,7-diazapyrene, 2,3-diazapyrene, 1,6-diazapyrene, 1,8-diazapyrene, 4,5-diazapyrene, 4,5,9,10-tetraazaperyl, pyrazinyl, phenazinyl, phenthiazinyl, naphridinyl, azacarbazolyl, benzocarbaolinyl, phenanthrolinel, 1,2,3-triazolyl, 1,2,4-triazolyl, benzotriazole One of the following: 1,2,3-oxadiazolyl, 1,2,4-oxadiazolyl, 1,2,5-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-tetraazinyl, 1,2,3,4-tetraazinyl, 1,2,3,5-tetraazinyl, purinyl, pteridyl, indazyl, benzothiadiazolyl, 9,9-dimethylacridyl, triarylamine, fluorophenyl, methylphenyl, trimethylphenyl, cyanophenyl.

[0020] In a second aspect of the present invention, a simple method for preparing carbene currency metal complexes is provided, comprising the following steps:

[0021] (1) A cyclic alkylamino carbene quaternary ammonium salt modified with a five-membered ring flanking was reacted with a monovalent monetary metal source under alkaline conditions to obtain a coordination intermediate;

[0022] (2) The coordination intermediate reacts with the carbazole ligand raw material under nucleophilic reaction conditions to obtain a carbene currency metal complex.

[0023] Preferably, the method for preparing the cyclic alkylamino carbene quaternary ammonium salt modified with five-membered ring sidewalls is as follows:

[0024] S1. Dissolve substituted or unsubstituted cyclopentylformaldehyde and aromatic amine raw materials in toluene, carry out a condensation reaction, and obtain a carbene intermediate after separation and purification.

[0025] S2. The carbene intermediate is dissolved in an organic solvent and subjected to a first-stage reaction under a protective gas atmosphere and alkaline conditions. Then, methyl propylene oxide is added and a second-stage reaction is carried out. Finally, trifluoromethanesulfonic anhydride is added to carry out a third-stage reaction to complete intramolecular ring closure and salt formation. After separation and purification, a cyclic alkylamino carbene quaternary ammonium salt modified with five-membered ring flanking is obtained.

[0026] More preferably, in step S1, the molar ratio of the substituted or unsubstituted cyclopentylformaldehyde to the aromatic amine raw material is 1:1 to 2.

[0027] More preferably, in step S1, the temperature of the condensation reaction is 100–120°C, and the reaction time is 36–72 h.

[0028] More preferably, in step S2, the organic solvent is at least one of diethyl ether and tetrahydrofuran.

[0029] More preferably, in step S2, the alkaline condition is achieved by adding an organic base, and the molar ratio of the carbene intermediate to the organic base is 1:1 to 2, wherein the organic base is one of n-butyllithium and diisopropylaminolithium.

[0030] More preferably, in step S2, the molar ratio of the carbene intermediate to the methyl propylene oxide is 1:1.2 to 1.5; and the molar ratio of the carbene intermediate to the trifluoromethanesulfonic anhydride is 1:1.2 to 1.5.

[0031] More preferably, in step S2, the temperature of the first stage reaction is room temperature and the reaction time is 2-6 hours; the temperature of the second stage reaction is room temperature and the reaction time is 8-12 hours; and the temperature of the third stage reaction is room temperature and the reaction time is 5-12 hours.

[0032] Preferably, in step (1), the molar ratio of the cyclic alkylamino carbene quaternary ammonium salt modified with the five-membered ring sidewalls to the monovalent monetary metal source is 1:1 to 2.

[0033] Preferably, in step (1), the monovalent monetary metal source is a chloride or oxide of a monovalent monetary metal.

[0034] Preferably, in step (1), the alkaline condition is achieved by adding an organic base, the concentration of which is 1.0 to 2.5 M, and the molar ratio of the cyclic alkylamino carbene quaternary ammonium salt modified with a five-membered ring sidewall to the organic base is 1:1.5 to 2.5. The organic base is one of bis(trimethylsilane)aminopotassium, n-butyllithium, diisopropylaminolithium, sodium tert-butoxide, and potassium tert-butoxide.

[0035] Preferably, in step (1), the reaction temperature is -78 to 25°C and the reaction time is 12 to 72 hours.

[0036] Preferably, in step (2), the molar ratio of the coordination intermediate to the carbazole ligand raw material is 1:1 to 1.5, and the carbazole ligand raw material is a hydrogen-substituted carbazole ligand.

[0037] Preferably, in step (2), the nucleophilic reaction conditions are created by adding an inorganic base, wherein the molar ratio of the coordination intermediate to the inorganic base is 1:1.5 to 3, and the inorganic base is one of potassium carbonate, cesium carbonate, and sodium hydride.

[0038] Preferably, in step (2), the reaction temperature is 35-50°C and the reaction time is 12-48h.

[0039] In a third aspect of the invention, an application is provided of the carbene currency metal complex of the first aspect of the invention or the carbene currency metal complex prepared by the preparation method of the second aspect of the invention, specifically the application of the carbene currency metal complex as a luminescent material in the preparation of electroluminescent devices or electrosensitized luminescent devices.

[0040] Preferably, the method for fabricating the electroluminescent device includes the following steps:

[0041] Using a carbene currency metal complex film or a doped film formed by a carbene currency metal complex and an OLED host material as the light-emitting layer of an electroluminescent device, an evaporation or spin-coating process is adopted, and a functional layer is combined according to the characteristics of the light-emitting layer to obtain an evaporation-type or spin-coating type electroluminescent device.

[0042] Preferably, the method for fabricating the electrosensitized light-emitting device includes the following steps:

[0043] Using a ternary doped film formed by the OLED host material, a carbene currency metal complex, and a narrow-emitting light-emitting material, or a binary doped film formed by the carbene currency metal complex and a narrow-emitting light-emitting material, as the light-emitting layer, an evaporation or spin-coating process is employed. Based on the characteristics of the light-emitting layer, a functional layer is combined to obtain an evaporation-deposited or spin-coated electrosensitized light-emitting device.

[0044] Further preferably, the structure of the vapor-deposited electroluminescent device or the vapor-deposited sensitized electroluminescent device, from bottom to top, consists of a glass substrate, an anode, a hole injection layer, a hole transport layer, an electron blocking layer, a light-emitting layer, a hole blocking layer, an electron transport layer, an electron injection layer, and a cathode.

[0045] More preferably, the structure of the spin-coated electroluminescent device or the spin-coated sensitized electroluminescent device, from bottom to top, consists of a glass substrate, an anode, a hole injection layer, a light-emitting layer, a hole blocking layer, an electron transport layer, an electron injection layer, and a cathode.

[0046] Compared with the prior art, the present invention has the following advantages and beneficial effects:

[0047] This invention provides a carbene currency metal complex, which is formed by a monovalent currency metal complex with a cyclic alkylamino carbene ligand and a carbazole ligand modified with a five-membered ring sidewall. The complex exhibits thermally activated delayed fluorescence and a high photoinduced quantum yield.

[0048] This invention provides a method for preparing carbene currency metal complexes. This method is simple, uses less expensive ligand materials, and is easier to synthesize. It solves the technical problems of expensive raw materials and difficult synthesis of existing cyclic alkylamino carbene ligands, and can prepare different types and emission types of carbene currency metal complexes according to actual needs.

[0049] This invention provides an application of carbene coin metal complexes, using these complexes as luminescent materials to prepare electroluminescent devices or electrosensitized luminescent devices. This solves the technical problems of low efficiency and material scarcity in existing electroluminescent devices. Furthermore, the carbene coin metal complex can sensitize luminescent materials with narrow emission characteristics, solving the technical problems of low color purity and low efficiency in such devices. Attached Figure Description

[0050] Figure 1 This is the general structural formula for vapor-deposited electroluminescent devices;

[0051] Figure 2 Comparison of transient luminescence lifetimes of the carbene coin metal complex and the comparative substance in Example 2;

[0052] Figure 3 The efficiency and electroluminescent spectrum of the electroluminescent device containing the carbene coin metal complex of Example 2 are shown. Detailed Implementation

[0053] The present invention is further illustrated below by way of embodiments, but the invention is not limited to the scope of the embodiments described herein. Experimental methods in the following embodiments that do not specify specific conditions were performed according to conventional methods and conditions, or as selected according to the product instructions.

[0054] In the following embodiments:

[0055] HAT-CN: 2,3,6,7,10,11-hexacyano-1,4,5,8,9,12-hexaazabenzophenanthrene;

[0056] TAPC: 4,4'-cyclohexylenebis[N,N-di(p-tolyl)aniline];

[0057] TCTA: 4,4,4-tris(carbazole-9-yl)triphenylamine;

[0058] mCBP: 3,3'-bis(N-carbazole)-1,1'-biphenyl;

[0059] PPF: 2,8-bis(diphenylphospho)dibenzo[b,d]furan;

[0060] ANT-BIZ: (1-(4-(10-([1,1'-biphenyl]-4-yl)anthracene-9-yl)phenyl)-2-ethyl-1H-benzo[d]-imidazolium);

[0061] Liq: Lithium 8-hydroxyquinoline;

[0062] Diisopropylaminolithium, specification: 2 mol / L in THF;

[0063] Bis(trimethylsilane)aminopotassium, specification: 1 mol / L in THF.

[0064] Example 1

[0065] Preparation of several important intermediates:

[0066] Preparation of (intermediate 1):

[0067]

[0068] (1) Synthesis of 1-cyclopentyl-N-(2,6-diisopropylphenyl)methylimine:

[0069] 5.0 g (51 mmol) of cyclopentyl formaldehyde and 17.7 g (100 mmol) of diisopropylaniline were added to a 250 mL single-necked flask, and 150 mL of toluene was added. The mixture was reacted at 100 °C for 48 h. After the reaction was completed, the mixture was filtered, the filtrate was collected, toluene was removed by vacuum distillation, ethanol was added to precipitate the solid, and 6.3 g of white solid was obtained by filtration.

[0070] (2) Synthesis of 1-[(2',6'-diisopropylphenyl)-5,5-dimethyl(cyclopentane-2,3-pyrrole)]trifluoromethanesulfonate:

[0071] 2 g (7.8 mmol) of 1-cyclopentyl-N-(2,6-diisopropylphenyl)methylimine was placed in a 50 mL two-necked flask, and 40 mL of anhydrous tetrahydrofuran was added. Under argon protection and an ice-water bath at 0 °C, 4.7 mL (2 mol / L in THF) of diisopropylaminolithium was added dropwise. The mixture was then stirred at room temperature for 2 h, followed by the addition of 0.6 mL (8.6 mmol) of methyl propylene oxide, and the reaction was allowed to proceed overnight at room temperature. Then, 3.3 mL (11.7 mmol) of trifluoromethanesulfonic anhydride was added in a -78 °C cold bath, and the mixture was stirred at room temperature for 6 h. The product was then filtered to obtain 2.6 g of a white solid. The mass spectrometry results of this product were: MS (EI): m / z 461.6 [M + The test results match the theoretical molecular weight of the molecule.

[0072] Preparation of (intermediate 2):

[0073]

[0074] (1) Synthesis of 1-cyclopentyl-N-(2,4,6-trimethylphenyl)methylimine:

[0075] 5.0 g (51 mmol) of cyclopentyl formaldehyde and 13.5 g (100 mmol) of trimethylolamine were added to a 250 mL single-necked flask, and 150 mL of toluene was added. The mixture was reacted at 100 °C for 48 h. After the reaction was completed, the mixture was filtered, the filtrate was collected, toluene was removed by vacuum distillation, ethanol was added to precipitate the solid, and 5.9 g of white solid was obtained by filtration.

[0076] (2) Synthesis of 1-[(2',4'6'-trimethylphenyl)-5,5-dimethyl(cyclopentane-2,3-pyrrole)]trifluoromethanesulfonate:

[0077] 1.7 g (7.8 mmol) of 1-cyclopentyl-N-(2,4,6-trimethylphenyl)methylimine was placed in a 50 mL two-necked flask, and 40 mL of anhydrous tetrahydrofuran was added. Under argon protection and an ice-water bath at 0 °C, 4.7 mL (2 mol / L in THF) of diisopropylaminolithium was added dropwise. The mixture was then stirred at room temperature for 2 h, followed by the addition of 0.6 mL (8.6 mmol) of methyl propylene oxide, and the reaction was allowed to proceed overnight at room temperature. Then, 3.3 mL (11.7 mmol) of trifluoromethanesulfonic anhydride was added in a -78 °C cold bath, and the mixture was stirred at room temperature for 6 h. The product was then filtered to obtain 2.2 g of a white solid. The mass spectrometry results of this product were: MS (EI): m / z 419.2 [M + The test results match the theoretical molecular weight of the molecule.

[0078] Preparation of (intermediate 3):

[0079]

[0080] (1) Synthesis of N-(2,6-diisopropylphenyl)-1-(tetrahydrofuran-3-yl)methylimine:

[0081] 5.1 g (51 mmol) of tetrahydrofuran-3-carboxaldehyde and 13.5 g (100 mmol) of diisopropylaniline were added to a 250 mL single-necked flask, and 150 mL of toluene was added. The mixture was reacted at 100 °C for 48 h. After the reaction was completed, the mixture was filtered, the filtrate was collected, toluene was removed by vacuum distillation, ethanol was added to precipitate the solid, and 4.9 g of white solid was obtained by filtration.

[0082] (2) Synthesis of 1-[(2',6'-diisopropylphenyl)-5,5-dimethyl((tetrahydrofuran-3-yl)-2,3-pyrrole)]trifluoromethanesulfonate:

[0083] 2 g (7.8 mmol) of N-(2,6-diisopropylphenyl)-1-(tetrahydrofuran-3-yl)methylimine was placed in a 50 mL two-necked flask, and 40 mL of anhydrous tetrahydrofuran was added. Under argon protection and an ice-water bath at 0 °C, 4.7 mL (2 mol / L inTHF) of diisopropylaminolithium was added dropwise. The mixture was then stirred at room temperature for 2 h, followed by the addition of 0.6 mL (8.6 mmol) of methyl propylene oxide, and the reaction was allowed to proceed overnight at room temperature. Then, 3.3 mL (11.7 mmol) of trifluoromethanesulfonic anhydride was added in a -78 °C cold bath, and the mixture was stirred at room temperature for 6 h. The product was filtered to obtain 2.4 g of a white solid. The mass spectrometry results of this product were: MS (EI): m / z 463.6 [M + The test results match the theoretical molecular weight of the molecule.

[0084] Preparation of (intermediate 4):

[0085]

[0086]

[0087] (1) Synthesis of 1-fluorenyl-N-(2,6-diisopropylphenyl)methylimine:

[0088] 9.9 g (51 mmol) of 9-fluorenaldehyde and 17.7 g (100 mmol) of diisopropylaniline were added to a 250 mL single-necked flask, and 150 mL of toluene was added. The mixture was reacted at 100 °C for 48 h. After the reaction was completed, the mixture was filtered, and the filtrate was collected. Toluene was removed by vacuum distillation, and ethanol was added to precipitate the solid. The solid was then filtered to obtain 10.2 g of white solid.

[0089] (2) Synthesis of 1-[(2',6'-diisopropylphenyl)-5,5-dimethyl(fluorenyl-2,3-pyrrole)]trifluoromethanesulfonate:

[0090] 2.6 g (7.8 mmol) of 1-cyclopentyl-N-(2,6-diisopropylphenyl)methylimine was placed in a 50 mL two-necked flask, and 40 mL of anhydrous tetrahydrofuran was added. Under argon protection and an ice-water bath at 0 °C, 4.7 mL (2 mol / L in THF) of diisopropylaminolithium was added dropwise. The mixture was then stirred at room temperature for 2 h, followed by the addition of 0.6 mL (8.6 mmol) of methyl propylene oxide, and the reaction was allowed to proceed overnight at room temperature. Then, 3.3 mL (11.7 mmol) of trifluoromethanesulfonic anhydride was added in a -78 °C cold bath, and the mixture was stirred at room temperature for 6 h. The product was then filtered to obtain 3.1 g of a white solid. The mass spectrometry results of this product were: MS (EI): m / z 557.2 [M + The test results match the theoretical molecular weight of the molecule.

[0091] Example 2

[0092] Preparation of ((carbazole-9-yl)[1-(2,6-diisopropylphenyl)-5,5-dimethyl(cyclopentane-2,3-pyrrolidine)-2-carbene]copper(I)):

[0093]

[0094]

[0095] (1) Synthesis of 1-[(2',6'-diisopropylphenyl)-5,5-dimethyl(cyclopentane-2,3-pyrrolidine)-2-carbene)]cuprous chloride (I):

[0096] 3 g (6.5 mmol) of 1-[(2',6'-diisopropylphenyl)-5,5-dimethyl(cyclopentane-2,3-pyrrole)]trifluoromethanesulfonate and 711 mg (7.2 mmol) of cuprous chloride were added to a 100 mL Scheranck flask, followed by 20 mL of anhydrous tetrahydrofuran. Under argon protection and a cold bath at 0 °C, 13 mL (1 mmol / mL in THF) of bis(trimethylsilane)amino potassium was added dropwise. After reacting for 24 h, the product was extracted and separated by column chromatography to obtain 1.4 g of a white powder. The mass spectrometry results of this product were: MS (EI): m / z 409.2 [M + The test results match the theoretical molecular weight of the molecule.

[0097] (2) Synthesis of (carbazole-9-yl)[1-(2,6-diisopropylphenyl)-5,5-dimethyl(cyclopentane-2,3-pyrrolidine)-2-carbene]copper(I):

[0098] Under argon protection, 200 mg (0.5 mmol) of 1-[(2',6'-diisopropylphenyl)-5,5-dimethyl(cyclopentane-2,3-pyrrolidine)-2-carbene)]cuprous chloride (I), 84 mg (0.5 mmol) of carbazole, and 207 mg (1.5 mmol) of potassium carbonate were dissolved in 5 mL of anhydrous acetone. The mixture was stirred at 50 °C for 2 days. After the reaction was complete, the mixture was filtered and recrystallized several times with dichloromethane and n-hexane to give 176 mg of a white solid. The mass spectrometry results of this product were: MS (EI): m / z 540.3 [M + The test results match the theoretical molecular weight of the molecule.

[0099] Example 3

[0100] Preparation of ((1-isopropyl-carbazole-9-yl)[1-(2,6-diisopropylphenyl)-5,5-dimethyl(cyclopentane-2,3-pyrrolidine)-2-carbene]copper(I)):

[0101]

[0102] (1) In this embodiment, the synthesis steps of 1-[(2',6'-diisopropylphenyl)-5,5-dimethyl(cyclopentane-2,3-pyrrolidine)-2-carbene)]cuprous chloride (I) are the same as in Example 2;

[0103] (2) Synthesis of (1-isopropyl-carbazole-9-yl)[1-(2,6-diisopropylphenyl)-5,5-dimethyl(cyclopentane-2,3-pyrrolidine)-2-carbene]copper(I):

[0104] Under argon protection, 200 mg (0.5 mmol) of 1-[(2',6'-diisopropylphenyl)-5,5-dimethyl(cyclopentane-2,3-pyrrolidine)-2-carbene)]cuprous chloride (I), 105 mg (0.5 mmol) of 1-isopropyl-carbazole and 207 mg (1.5 mmol) of potassium carbonate were dissolved in 5 mL of anhydrous acetone. The reaction was stirred at 50 °C for 2 days. After the reaction was completed, the mixture was filtered and recrystallized several times with dichloromethane and n-hexane to give 163 mg of a white solid. The mass spectrometry results of this product were: MS (EI): m / z 582.3 [M + The test results match the theoretical molecular weight of the molecule.

[0105] Example 4

[0106] Preparation of ((3,6-di-tert-butyl-carbazole-9-yl)[1-(2,6-diisopropylphenyl)-5,5-dimethyl(cyclopentane-2,3-pyrrolidine)-2-carbene]copper(I)):

[0107]

[0108] (1) In this embodiment, the synthesis steps of 1-[(2',6'-diisopropylphenyl)-5,5-dimethyl(cyclopentane-2,3-pyrrolidine)-2-carbene)]cuprous chloride (I) are the same as in Example 2;

[0109] (2) Synthesis of (3,6-di-tert-butyl-carbazole-9-yl)[1-(2,6-diisopropylphenyl)-5,5-dimethyl(cyclopentane-2,3-pyrrolidine)-2-carbene]copper(I):

[0110] Under argon protection, 200 mg (0.5 mmol) of 1-[(2',6'-diisopropylphenyl)-5,5-dimethyl(cyclopentane-2,3-pyrrolidine)-2-carbene)]cuprous chloride (I), 140 mg (0.5 mmol) of 3,6-di-tert-butyl-carbazole and 207 mg (1.5 mmol) of potassium carbonate were dissolved in 5 mL of anhydrous acetone. The reaction was stirred at 50 °C for 2 days. After the reaction was completed, the mixture was filtered and recrystallized several times with dichloromethane and n-hexane to give 265 mg of a yellow solid. The mass spectrometry results of this product were: MS (EI): m / z 652.4 [M + The test results match the theoretical molecular weight of the molecule.

[0111] Example 5

[0112] Preparation of ((3,6-di-tert-butyl-carbazole-9-yl)[1-(2,6-diisopropylphenyl)-5,5-dimethyl(cyclopentane-2,3-pyrrolidine)-2-carbene]copper(I)):

[0113]

[0114] (1) In this embodiment, the synthesis steps of 1-[(2',6'-diisopropylphenyl)-5,5-dimethyl(cyclopentane-2,3-pyrrolidine)-2-carbene)]cuprous chloride (I) are the same as in Example 2;

[0115] Synthesis of (2)(2)(3,6-di-tert-butyl-carbazole-9-yl)[1-(2,6-diisopropylphenyl)-5,5-dimethyl(cyclopentane-2,3-pyrrolidine)-2-carbene]copper(I):

[0116] Under argon protection, 200 mg (0.5 mmol) of 1-[(2',6'-diisopropylphenyl)-5,5-dimethyl(cyclopentane-2,3-pyrrolidine)-2-carbene)]cuprous chloride (I), 113 mg (0.5 mmol) of 3,6-dimethoxy-carbazole, and 207 mg (1.5 mmol) of potassium carbonate were dissolved in 5 mL of anhydrous acetone. The reaction was stirred at 50 °C for 2 days. After the reaction was completed, the mixture was filtered and recrystallized several times with dichloromethane and n-hexane to give 193 mg of a yellow solid. The mass spectrometry results of this product were: MS (EI): m / z 600.3 [M + The test results match the theoretical molecular weight of the molecule.

[0117] Example 6

[0118] Preparation of ((benzo[2,3-b]furancarbazole-7-yl)[1-(2,6-diisopropylphenyl)-5,5-dimethyl(cyclopentane-2,3-pyrrolidine)-2-carbene]copper(I)):

[0119]

[0120] (1) In this embodiment, the synthesis steps of 1-[(2',6'-diisopropylphenyl)-5,5-dimethyl(cyclopentane-2,3-pyrrolidine)-2-carbene)]cuprous chloride (I) are the same as in Example 2;

[0121] (2) Synthesis of (benzo[2,3-b]furancarbazole-7-yl)[1-(2,6-diisopropylphenyl)-5,5-dimethyl(cyclopentane-2,3-pyrrolidine)-2-carbene]copper(I):

[0122] Under argon protection, 200 mg (0.5 mmol) of 1-[(2',6'-diisopropylphenyl)-5,5-dimethyl(cyclopentane-2,3-pyrrolidine)-2-carbene)]cuprous chloride (I), 150 mg (0.5 mmol) of 7H-benzo[2,3-b]furancarbazole and 207 mg (1.5 mmol) of potassium carbonate were dissolved in 5 mL of anhydrous acetone. The reaction was stirred at 50 °C for 2 days. After the reaction was completed, the mixture was filtered and recrystallized several times with dichloromethane and n-hexane to give 253 mg of a yellow solid. The mass spectrometry results of this product were: MS (EI): m / z 672.3 [M + The test results match the theoretical molecular weight of the molecule.

[0123] Example 7

[0124] Preparation of ((carbazole-9-yl)[1-(2,6-diisopropylphenyl)-5,5-dimethyl(fluorenyl-2,3-pyrrolidine)-2-carbene]copper(I)):

[0125]

[0126] (1) Synthesis of 1-[(2',6'-diisopropylphenyl)-5,5-dimethyl(fluorenyl-2,3-pyrrolidine)-2-carbene)]cuprous chloride (I):

[0127] 3.6 g (6.5 mmol) of 1-[(2',6'-diisopropylphenyl)-5,5-dimethyl(fluorenyl-2,3-pyrrole)]trifluoromethanesulfonate and 711 mg (7.2 mmol) of cuprous chloride were added to a 100 mL Scheranck flask, followed by 20 mL of anhydrous tetrahydrofuran. Under argon protection and a cold bath at 0 °C, 13 mL (1 mmol / mL in THF) of bis(trimethylsilane)amino potassium was added dropwise. After reacting for 24 h, the product was extracted and separated by column chromatography to obtain 1.4 g of a white powder. The mass spectrometry results of this product were: MS (EI): m / z 505.2 [M + The test results match the theoretical molecular weight of the molecule.

[0128] (2) Synthesis of (carbazole-9-yl)[1-(2,6-diisopropylphenyl)-5,5-dimethyl(fluorenyl-2,3-pyrrolidine)-2-carbene]copper(I):

[0129] Under argon protection, 253 mg (0.5 mmol) of 1-[(2',6'-diisopropylphenyl)-5,5-dimethyl(cyclopentane-2,3-pyrrolidine)-2-carbene)]cuprous chloride (I), 84 mg (0.5 mmol) of carbazole, and 207 mg (1.5 mmol) of potassium carbonate were dissolved in 5 mL of anhydrous acetone. The reaction was stirred at 50 °C for 2 days. After the reaction was completed, the mixture was filtered and recrystallized several times with dichloromethane and n-hexane to give 241 mg of a white solid. The mass spectrometry results of this product were: MS (EI): m / z 636.3 [M + The test results match the theoretical molecular weight of the molecule.

[0130] Example 8

[0131] Preparation of ((carbazole-9-yl)[1-(2,6-diisopropylphenyl)-5,5-dimethyl(fluorenyl-2,3-pyrrolidine)-2-carbene]copper(I)):

[0132]

[0133] (1) In this embodiment, the synthesis steps of 1-[(2',6'-diisopropylphenyl)-5,5-dimethyl(fluorenyl-2,3-pyrrolidine)-2-carbene)]cuprous chloride (I) are the same as in Example 7;

[0134] (2) Synthesis of (carbazole-9-yl)[1-(2,6-diisopropylphenyl)-5,5-dimethyl(fluorenyl-2,3-pyrrolidine)-2-carbene]copper(I):

[0135] Under argon protection, 253 mg (0.5 mmol) of 1-[(2',6'-diisopropylphenyl)-5,5-dimethyl(cyclopentane-2,3-pyrrolidine)-2-carbene)]cuprous chloride (I), 104 mg (0.5 mmol) of 1-isopropylcarbazole and 207 mg (1.5 mmol) of potassium carbonate were dissolved in 5 mL of anhydrous acetone. The reaction was stirred at 50 °C for 2 days. After the reaction was completed, the mixture was filtered and recrystallized several times with dichloromethane and n-hexane to give 241 mg of a white solid. The mass spectrometry results of this product were: MS (EI): m / z 678.3 [M + The test results match the theoretical molecular weight of the molecule.

[0136] Example 9

[0137] Preparation of ((carbazole-9-yl)[1-(2,6-diisopropylphenyl)-5,5-dimethyl(tetrahydrofuran-2,3-pyrrolidine)-2-carbene]copper(I)):

[0138]

[0139]

[0140] (1) Synthesis of 1-[(2',6'-diisopropylphenyl)-5,5-dimethyl((tetrahydrofuran-3-yl)-2,3-pyrrolidine)-2-carbene)]cuprous chloride (I):

[0141] 3.1 g (6.5 mmol) of 1-[(2',6'-diisopropylphenyl)-5,5-dimethyl((tetrahydrofuran-3-yl)-2,3-pyrrole)]trifluoromethanesulfonate and 711 mg (7.2 mmol) of cuprous chloride were added to a 100 mL Scheranck flask, followed by 20 mL of anhydrous tetrahydrofuran. Under argon protection and a 0°C cryogenic bath, 13 mL (1 mmol / mL in THF) of bis(trimethylsilane)amino potassium was added dropwise. After reacting for 24 h, the product was extracted and separated by column chromatography to obtain 1.6 g of a white powder. The mass spectrometry results of this product were: MS (EI): m / z 411.2 [M + The test results match the theoretical molecular weight of the molecule.

[0142] (2) Synthesis of (carbazole-9-yl)[1-(2,6-diisopropylphenyl)-5,5-dimethyl(tetrahydrofuran-2,3-pyrrolidine)-2-carbene]copper(I):

[0143] Under argon protection, 205 mg (0.5 mmol) of 1-[(2',6'-diisopropylphenyl)-5,5-dimethyl(cyclopentane-2,3-pyrrolidine)-2-carbene)]cuprous chloride (I), 84 mg (0.5 mmol) of carbazole, and 207 mg (1.5 mmol) of potassium carbonate were dissolved in 5 mL of anhydrous acetone. The mixture was stirred at 50 °C for 2 days. After the reaction was complete, the mixture was filtered and recrystallized several times with dichloromethane and n-hexane to give 212 mg of a white solid. The mass spectrometry results of this product were: MS (EI): m / z 584.3 [M + The test results match the theoretical molecular weight of the molecule.

[0144] Example 10

[0145] Preparation of ((benzo[2,3-a]thiophenecarbazo-12-yl)[1-(2,6-diisopropylphenyl)-5,5-dimethyl(tetrahydrofuran-2,3-pyrrolidine)-2-carbene]copper(I)):

[0146]

[0147] (1) In this embodiment, the synthesis steps of 1-[(2',6'-diisopropylphenyl)-5,5-dimethyl(tetrahydrofuran-2,3-pyrrolidine)-2-carbene)]cuprous chloride (I) are the same as in Example 9;

[0148] (2) Synthesis of (benzo[2,3-a]thiophenecarbazo-12-yl)[1-(2,6-diisopropylphenyl)-5,5-dimethyl(tetrahydrofuran-2,3-pyrrolidine)-2-carbene]copper(I):

[0149] Under argon protection, 205 mg (0.5 mmol) of 1-[(2',6'-diisopropylphenyl)-5,5-dimethyl(cyclopentane-2,3-pyrrolidine)-2-carbene)]cuprous chloride (I), 137 mg (0.5 mmol) of 12H-benzo[2,3-a]thiophenecarbazole and 207 mg (1.5 mmol) of potassium carbonate were dissolved in 5 mL of anhydrous acetone. The reaction was stirred at 50 °C for 2 days. After the reaction was completed, the mixture was filtered and recrystallized several times with dichloromethane and n-hexane to give 262 mg of a white solid. The mass spectrometry results of this product were: MS (EI): m / z 648.2 [M + The test results match the theoretical molecular weight of the molecule.

[0150] Example 11

[0151] Preparation of ((carbazole-9-yl)[1-(2,6-diisopropylphenyl)-5,5-dimethyl(tetrahydrothiophene-2,3-pyrrolidine)-2-carbene]copper(I)):

[0152]

[0153]

[0154] (1) Synthesis of 1-[(2',6'-diisopropylphenyl)-5,5-dimethyl((tetrahydrothiophene-3-yl)-2,3-pyrrolidine)-2-carbene)]cuprous chloride (I):

[0155] 3.1 g (6.5 mmol) of 1-[(2',6'-diisopropylphenyl)-5,5-dimethyl((tetrahydrothiophen-3-yl)-2,3-pyrrole)]trifluoromethanesulfonate and 711 mg (7.2 mmol) of cuprous chloride were added to a 100 mL Scheranck flask, followed by 20 mL of anhydrous tetrahydrofuran. Under argon protection and a cold bath at 0 °C, 13 mL (1 mmol / mL in THF) of bis(trimethylsilane)amino potassium was added dropwise. After reacting for 24 h, the product was extracted and separated by column chromatography to obtain 1.6 g of a white powder. The mass spectrometry results of this product were: MS (EI): m / z 427.1 [M + The test results match the theoretical molecular weight of the molecule.

[0156] (2) Synthesis of (carbazole-9-yl)[1-(2,6-diisopropylphenyl)-5,5-dimethyl(tetrahydrothiophene-2,3-pyrrolidine)-2-carbene]copper(I):

[0157] Under argon protection, 205 mg (0.5 mmol) of 1-[(2',6'-diisopropylphenyl)-5,5-dimethyl(tetrahydrothiophene-2,3-pyrrolidine)-2-carbene)]cuprous chloride (I), 84 mg (0.5 mmol) of carbazole, and 207 mg (1.5 mmol) of potassium carbonate were dissolved in 5 mL of anhydrous acetone. The reaction was stirred at 50 °C for 2 days. After the reaction was completed, the mixture was filtered and recrystallized several times with dichloromethane and n-hexane to give 227 mg of a white solid. The mass spectrometry results of this product were: MS (EI): m / z 558.2 [M + The test results match the theoretical molecular weight of the molecule.

[0158] Example 12

[0159] Preparation of ((carbazole-9-yl)[1-(2,6-diisopropylphenyl)-5,5-dimethyl(cyclopentane-2,3-pyrrolidine)-2-carbene]silver(I)):

[0160]

[0161] (1) Synthesis of 1-[(2',6'-diisopropylphenyl)-5,5-dimethyl(cyclopentane-2,3-pyrrolidine)-2-carbene)]silver chloride (I):

[0162] 3 g (6.5 mmol) of 1-[(2',6'-diisopropylphenyl)-5,5-dimethyl(cyclopentane-2,3-pyrrole)]trifluoromethanesulfonate and 1.7 g (7.2 mmol) of silver oxide were added to a 100 mL Scheranck flask, followed by 20 mL of anhydrous tetrahydrofuran. Under a -78°C cryogenic bath and argon protection, 9.5 mL (2 mmol / mL in THF) of diisopropylaminolithium was added dropwise. After quenching the reaction with ice water, the silver oxide solid was removed by filtration. The filtrate was evaporated to dryness and recrystallized to obtain 1.2 g of white crystalline powder. The mass spectrometry results of this product were: MS (EI): m / z 453.1 [M + The test results match the theoretical molecular weight of the molecule.

[0163] (2) Synthesis of (carbazole-9-yl)[1-(2,6-diisopropylphenyl)-5,5-dimethyl(cyclopentane-2,3-pyrrolidine)-2-carbene]silver(I):

[0164] Under argon protection, 215 mg (0.5 mmol) of 1-[(2',6'-diisopropylphenyl)-5,5-dimethyl(cyclopentane-2,3-pyrrolidine)-2-carbene)]silver chloride (I), 84 mg (0.5 mmol) of carbazole, and 207 mg (1.5 mmol) of potassium carbonate were dissolved in 5 mL of anhydrous acetone. The mixture was stirred at 50 °C for 2 days. After the reaction was complete, the mixture was filtered and recrystallized several times with dichloromethane and n-hexane to give 213 mg of a white solid. The mass spectrometry results of this product were: MS (EI): m / z 584.2 [M + The test results match the theoretical molecular weight of the molecule.

[0165] Example 13

[0166] Preparation of ((1-isopropyl-carbazole-9-yl)[1-(2,6-diisopropylphenyl)-5,5-dimethyl(cyclopentane-2,3-pyrrolidine)-2-carbene]silver(I)):

[0167]

[0168] (1) In this embodiment, the synthesis steps of 1-[(2',6'-diisopropylphenyl)-5,5-dimethyl(cyclopentane-2,3-pyrrolidine)-2-carbene)]silver chloride (I) are the same as in Example 12;

[0169] (2) Synthesis of (1-isopropyl-carbazole-9-yl)[1-(2,6-diisopropylphenyl)-5,5-dimethyl(cyclopentane-2,3-pyrrolidine)-2-carbene]silver(I):

[0170] Under argon protection, 215 mg (0.5 mmol) of 1-[(2',6'-diisopropylphenyl)-5,5-dimethyl(cyclopentane-2,3-pyrrolidine)-2-carbene)]silver chloride (I), 105 mg (0.5 mmol) of carbazole, and 207 mg (1.5 mmol) of potassium carbonate were dissolved in 5 mL of anhydrous acetone. The mixture was stirred at 50 °C for 2 days. After the reaction was complete, the mixture was filtered and recrystallized several times with dichloromethane and n-hexane to give 273 mg of a white solid. The mass spectrometry results of this product were: MS (EI): m / z 626.3 [M + The test results match the theoretical molecular weight of the molecule.

[0171] Example 14

[0172] Preparation of ((carbazole-9-yl)[1-(2,6-diisopropylphenyl)-5,5-dimethyl(cyclopentane-2,3-pyrrolidine)-2-carbene]gold(I)):

[0173]

[0174]

[0175] (1) Synthesis of 1-[(2',6'-diisopropylphenyl)-5,5-dimethyl(cyclopentane-2,3-pyrrolidine)-2-carbene)] gold chloride (I):

[0176] 3 g (6.5 mmol) of 1-[(2',6'-diisopropylphenyl)-5,5-dimethyl(cyclopentane-2,3-pyrrole)]trifluoromethanesulfonate and 2.1 g (7.2 mmol) of dimethyl sulfide gold chloride were added to a 100 mL Scheranck flask, followed by 20 mL of anhydrous tetrahydrofuran. Under argon protection and a cold bath at 0 °C, 13 mL (1 mmol / mL in THF) of bis(trimethylsilane)amino potassium was added dropwise. After reacting for 24 h, the product was extracted and separated by column chromatography to obtain 1.1 g of a white powder. The mass spectrometry results of this product were: MS (EI): m / z 543.2 [M + The test results match the theoretical molecular weight of the molecule.

[0177] (2) Synthesis of (carbazole-9-yl)[1-(2,6-diisopropylphenyl)-5,5-dimethyl(cyclopentane-2,3-pyrrolidine)-2-carbene] gold(I):

[0178] Under argon protection, 400 mg (0.13 mmol) of 1-[(2',6'-diisopropylphenyl)-5,5-dimethyl(cyclopentane-2,3-pyrrolidine)-2-carbene)]gold(I) chloride, 22 mg (0.13 mmol) of carbazole, and 55 mg (4.5 mmol) of potassium carbonate were dissolved in 5 mL of anhydrous acetone. The reaction was stirred at 50 °C for 2 days. After the reaction was completed, the mixture was filtered and recrystallized several times with dichloromethane and n-hexane to give 302 mg of a white solid. The mass spectrometry results of this product were: MS (EI): m / z 674.3 [M + The test results match the theoretical molecular weight of the molecule.

[0179] Example 15

[0180] Fabrication of blue light-emitting thermally activated delayed fluorescence evaporation electroluminescent devices:

[0181] The glass plate with a 150nm thick ITO transparent conductive layer was wiped with cotton soaked in acetone and ethanol, then rinsed with deionized water and ultrasonically cleaned with acetone and ethanol for 10 minutes. It was then baked in a clean environment until all moisture was removed and treated with ultraviolet light and ozone for 20 minutes.

[0182] The treated ITO glass substrate was placed in a vacuum chamber and evacuated to a vacuum level of 2 × 10⁻⁶. -4 ~5×10 -5 After Pa, each functional layer is vacuum-deposited on the aforementioned anode layer film, and the device structure is as follows. Figure 1 As shown, the layers are, in sequence, a hole injection layer, a hole transport layer, a hole transport layer, an electron blocking layer, a light-emitting layer, a hole blocking layer, an electron transport layer, an electron injection layer, and an aluminum cathode; the functional layer deposition rate is... The metal cathode evaporation rate is

[0183] In this embodiment, the glass substrate is ITO conductive glass, covered with an anode layer film; the hole injection layer is 5 nm thick and made of HAT-CN; the hole transport layer is 30 nm thick and made of TAPC; the hole transport layer is 15 nm thick and made of TCTA; the electron blocking layer is 10 nm thick and made of mCBP; the light-emitting layer is 20 nm thick and made of a pure film of the complex obtained in Example 2 or a doped film formed by the complex obtained in Example 2 and mCB at a mass ratio of 20:80; the hole blocking layer is 10 nm thick and made of PPF; the electron transport layer is 40 nm thick and made of ANT-BIZ; the electron injection layer is 1.5 nm thick and made of Liq; and the aluminum cathode layer is 100 nm thick.

[0184] Example 16

[0185] In this embodiment, the preparation method of the blue light evaporation type thermally activated delayed fluorescence electroluminescent device is basically the same as that in Example 15, except that the light-emitting layer material used in this embodiment is the complex obtained in Example 3.

[0186] In this embodiment, the glass substrate is ITO conductive glass, covered with an anode layer; the hole injection layer is 5 nm thick and made of HAT-CN; the hole transport layer is 30 nm thick and made of TAPC; the hole transport layer is 15 nm thick and made of TCTA; the electron blocking layer is 10 nm thick and made of mCBP; the light-emitting layer is 20 nm thick and made of a pure film of the complex obtained in Example 3 or a doped film formed by the complex obtained in Example 3 and mCB at a mass ratio of 20:80; the hole blocking layer is 10 nm thick and made of PPF; the electron transport layer is 40 nm thick and made of ANT-BIZ; the electron injection layer is 1.5 nm thick and made of Liq; and the aluminum cathode layer is 100 nm thick.

[0187] Example 17

[0188] In this embodiment, the preparation method of the vapor-deposited thermally activated delayed fluorescence electroluminescent device is basically the same as that in Example 15, except that the light-emitting layer material used in this embodiment is the complex obtained in Example 4.

[0189] In this embodiment, the glass substrate is ITO conductive glass, covered with an anode layer film; the hole injection layer is 5 nm thick and made of HAT-CN; the hole transport layer is 30 nm thick and made of TAPC; the hole transport layer is 15 nm thick and made of TCTA; the electron blocking layer is 10 nm thick and made of mCBP; the light-emitting layer is 20 nm thick and made of a pure film of the complex obtained in Example 4; the hole blocking layer is 10 nm thick and made of PPF; the electron transport layer is 40 nm thick and made of ANT-BIZ; the electron injection layer is 1.5 nm thick and made of Liq; and the aluminum cathode layer is 100 nm thick.

[0190] Example 18

[0191] Fabrication of blue narrow-emission evaporation-type sensitized electroluminescent devices:

[0192] In this embodiment, the preparation method of the blue narrow emission vapor deposition type sensitized electroluminescent device is basically the same as that in Example 15. The only difference is that the light-emitting layer material used in this embodiment is the complex obtained in Example 2 and υ-DABNA.

[0193] The compound structure of υ-DABNA is as follows:

[0194]

[0195] In this embodiment, the glass substrate is ITO conductive glass, covered with an anode layer film; the hole injection layer is 5 nm thick and made of HAT-CN; the hole transport layer is 30 nm thick and made of TAPC; the hole transport layer is 15 nm thick and made of TCTA; the electron blocking layer is 10 nm thick and made of mCBP; the light-emitting layer is 20 nm thick and made of mCBP; the complex of Example 2 is a ternary doped system of υ-DABNA = 89:10:1; the hole blocking layer is 10 nm thick and made of PPF; the electron transport layer is 40 nm thick and made of ANT-BIZ; the electron injection layer is 1.5 nm thick and made of Liq; and the aluminum cathode layer is 100 nm thick.

[0196] Electroluminescence spectra were obtained using a PR735 spectrometer; current-luminosity-voltage characteristics were obtained using a Keithley 2400 testing system with an attached LS-110 luminance meter. The maximum external quantum efficiency of this blue narrow-emission vapor-deposited sensitized electroluminescent device is 32.8%, and the CIE values ​​are x = 0.13 and y = 0.12.

[0197] Example 19

[0198] Fabrication of green narrow-emission vapor-deposited sensitized electroluminescent devices:

[0199] In this embodiment, the preparation method of the green narrow emission vapor deposition type sensitized electroluminescent device is basically the same as that in Example 15, except that the light-emitting layer material used in this embodiment is the complex obtained in Example 4 and BN2.

[0200] The compound structure of BN2 is as follows:

[0201]

[0202] Preferably, the glass substrate is ITO conductive glass, covered with an anode layer film; the hole injection layer is 5 nm thick and made of HAT-CN; the hole transport layer is 30 nm thick and made of TAPC; the hole transport layer is 15 nm thick and made of TCTA; the electron blocking layer is 10 nm thick and made of mCBP; the light-emitting layer is 20 nm thick and made of the complex of Example 4: a binary doped system of BN2 = 99:1; the hole blocking layer is 10 nm thick and made of PPF; the electron transport layer is 40 nm thick and made of ANT-BIZ; the electron injection layer is 1.5 nm thick and made of Liq; and the aluminum cathode layer is 100 nm thick.

[0203] Electroluminescence spectra were obtained using a PR735 spectrometer; current-luminosity-voltage characteristics were obtained using a Keithley 2400 testing system with an attached LS-110 luminance meter. The maximum external quantum efficiency of this green narrow-emission vapor-deposited sensitized electroluminescent device is 25.1%, and the CIE values ​​are x = 0.33 and y = 0.54.

[0204] Example 20

[0205] To characterize the photophysical properties of the above series of carbene currency metal complexes, the photoinduced quantum yield (PLQY) and exciton lifetime (τd) of the complexes obtained in Examples 2-4 in the film state (corresponding to Examples 15-17, respectively) were tested. Simultaneously, to further compare the effects of flanking modifications on the photophysical properties of the carbene currency metal complexes, a comparative material ((carbazole-9-yl)[1-(2',6'-diisopropylphenyl)-5,5-dimethyl(adamantane-2,3-pyrrolidine)-2-carbene)]copper(I)) was introduced in this example, along with its PLQY and τd. Electroluminescence spectroscopy was obtained using a PR735 spectrometer; current-brightness-voltage characteristics were obtained using a Keithley 2400 testing system equipped with an LS-110 luminometer; all tests were conducted in the atmosphere. The test results are shown in Table 1. Figure 2 A comparison of the transient luminescence lifetimes in the pure film state of the carbene money metal complex and the comparative material in Example 2 is given; Figure 3 The efficiency and electroluminescent spectrum of an electroluminescent device (Example 15) containing the carbene coin metal complex of Example 2 are presented.

[0206] Table 1:

[0207]

[0208] Compared to the comparative material, the carbene coin metal molecule modified with five-membered ring flanking exhibits higher PLQY, shorter delayed fluorescence lifetime, and superior device performance. Therefore, the present invention provides a carbene coin metal complex with better luminescent properties.

[0209] In summary, the carbene currency metal complexes of this invention exhibit significant thermally activated delayed fluorescence characteristics and potential for OLED fabrication. Their advantages are mainly reflected in two aspects: First, compared to carbene synthesis using adamantane as a flanking group, the cyclic alkylamino carbene modified with cyclopentane as a flanking group is readily available and inexpensive, and the corresponding carbene quaternary ammonium salt can be obtained in high yield in just two steps. Second, this series of flanked carbene currency metal complexes shows significant improvements in photon yield and exciton lifetime, and the devices fabricated based on them exhibit improved efficiency to a certain extent.

[0210] The preferred embodiments of the present invention have been described in detail above. It should be understood that those skilled in the art can make numerous modifications and variations based on the concept of the present invention without creative effort. Therefore, all technical solutions that can be obtained by those skilled in the art based on the concept of the present invention through logical analysis, reasoning, or limited experimentation on the basis of existing technology should be within the scope of protection defined by the claims.

Claims

1. A carbene coin metal complex, characterized in that, The structural formula of the carbene coin metal complex is as follows: ； Where M represents a monovalent monetary metal, A represents a cyclic alkylamino carbene ligand modified with a five-membered ring flanking, B represents a carbazole ligand, and R represents a sterically hindered group. The monovalent monetary metal is copper; the steric hindrance group is 2,6-diisopropylphenyl. The cyclic alkylamino carbene ligand modified with a five-membered ring flanking has the following structure: ； In the cyclic alkylamino carbene ligand modified with a five-membered ring flanking, Z1 is hydrogen; The carbazole ligand is selected from one of the following structures: 、 、 ； P1 and P2 are hydrogen atoms, respectively.

2. A method for preparing the carbene coin metal complex as described in claim 1, characterized in that, Includes the following steps: (1) A cyclic alkylamino carbene quaternary ammonium salt modified with a five-membered ring sidewall reacted with a monovalent monetary metal source under alkaline conditions to obtain a coordination intermediate; (2) The coordination intermediate reacts with the carbazole ligand raw material under nucleophilic reaction conditions to obtain a carbene currency metal complex; The preparation method of cyclic alkylamino carbene quaternary ammonium salts modified with five-membered ring flanking is as follows: S1. Cyclopentylformaldehyde and aromatic amine raw materials are dissolved in toluene and subjected to a condensation reaction. After separation and purification, a carbene intermediate is obtained. S2. The carbene intermediate is dissolved in an organic solvent and subjected to a first-stage reaction under a protective gas atmosphere and alkaline conditions. Then, methyl propylene oxide is added and a second-stage reaction is carried out. Finally, trifluoromethanesulfonic anhydride is added to carry out a third-stage reaction to complete intramolecular ring closure and salt formation. After separation and purification, a cyclic alkylamino carbene quaternary ammonium salt modified with five-membered ring flanking is obtained.

3. The method according to claim 2, characterized in that: In step S1, the molar ratio of cyclopentylformaldehyde to aromatic amine raw material is 1:1~2, the condensation reaction temperature is 100~120℃, and the reaction time is 36~72h. In step S2, the alkaline condition is achieved by adding an organic base, the molar ratio of carbene intermediate to organic base is 1:1~2, the organic base is one of n-butyllithium and diisopropylaminolithium, the molar ratio of carbene intermediate to methyl propylene oxide is 1:1.2~1.5, the molar ratio of carbene intermediate to trifluoromethanesulfonic anhydride is 1:1.2~1.5, the first stage reaction temperature is room temperature, and the reaction time is 2~6h; the second stage reaction temperature is room temperature, and the reaction time is 8~12h; the third stage reaction temperature is room temperature, and the reaction time is 5~12h.

4. The method according to claim 2, characterized in that: In step (1), the molar ratio of the cyclic alkylamino carbene quaternary ammonium salt modified with a five-membered ring sidewall to the monovalent monetary metal source is 1:1~2; the monovalent monetary metal source is a chloride or oxide of a monovalent monetary metal; the alkaline condition is achieved by adding an organic base, the concentration of which is 1.0~2.5M, the molar ratio of the cyclic alkylamino carbene quaternary ammonium salt modified with a five-membered ring sidewall to the organic base is 1:1.5~2.5, and the organic base is one of bis(trimethylsilane)aminopotassium, n-butyllithium, diisopropylaminolithium, sodium tert-butoxide, and potassium tert-butoxide; the reaction temperature is -78~25℃, and the reaction time is 12~72h.

5. The method according to claim 2, characterized in that: In step (2), the molar ratio of the coordination intermediate to the carbazole ligand raw material is 1:1 to 1.5, and the carbazole ligand raw material is a hydrogen-substituted carbazole ligand; the nucleophilic reaction conditions are created by adding an inorganic base, the molar ratio of the coordination intermediate to the inorganic base is 1:1.5 to 3, and the inorganic base is one of potassium carbonate, cesium carbonate, and sodium hydride; the reaction temperature is 35 to 50°C, and the reaction time is 12 to 48 hours.

6. The application of a carbene coin metal complex as described in claim 1 or a carbene coin metal complex prepared by the method described in any one of claims 2 to 5, characterized in that: Application of carbene coin metal complexes as luminescent materials in the fabrication of electroluminescent devices.

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