A benzophenone derivative organic luminescent material and its preparation method and application

Abstract

A benzophenone derivative organic luminescent material uses a benzophenone derivative as a backbone unit. By varying the chiral group, its heterocyclic atoms, and the number of connecting units on either side, the material's molecular weight, π conjugation, and circularly polarized luminescence properties can be adjusted. This organic luminescent material effectively addresses the problem of preparing high-efficiency circularly polarized luminescent materials, thereby improving the performance of such devices. The synthesis and purification processes for this material are simple, with high yields, making it suitable for large-scale production. Organic electroluminescent devices prepared using the luminescent material exhibiting both circularly polarized luminescence and thermally activated delayed fluorescence emission as a luminescent layer exhibit high luminescence brightness and external quantum efficiency, meeting practical requirements.

Description

Technical Field

[0001] The present invention belongs to the technical field of electroluminescent materials, and in particular relates to a benzophenone derivative organic luminescent material and a preparation method and application thereof. Background Art

[0002] Organic light-emitting diodes (OLEDs) have attracted significant attention from both academia and industry due to their advantages, including solid-state, self-luminescence, wide viewing angle, fast response, and lightweight and flexible design. They have become a mainstream development in the display industry, playing a crucial role in next-generation flat-panel displays and solid-state lighting. Within the entire OLED industry chain, organic light-emitting materials have always played a crucial role and represent one of the areas with the highest technical barriers. Currently, the majority of OLED light-emitting layer materials are traditional fluorescent materials, which, according to quantum statistics, can only utilize 25% of singlet excitons, severely impacting their luminescence performance. Thermally activated delayed fluorescence (TADF) materials have become a hot topic of research both domestically and internationally, due to their theoretical potential to achieve 100% exciton utilization while avoiding the use of costly precious metals. Therefore, high-efficiency TADF materials with independent intellectual property rights are expected to help resolve the current challenges in OLED material utilization. In recent years, organic circularly polarized light (CPL) luminescent and detection devices have garnered significant attention due to their potential applications in 3D displays, information processing, quantum communications, and bioimaging. Chiral organic optoelectronic materials are the core and foundation of these devices.

[0003] Common circularly polarized OLED displays are equipped with a circular polarizer consisting of a polarizer and a quarter-wave plate. However, 50% of the light emitted by traditional luminescent materials will be absorbed by the polarizer after passing through the quarter-wave plate, resulting in serious energy loss. In response to the above problems, the ideal solution is to develop luminescent materials that have both circularly polarized luminescence and thermally activated delayed fluorescence emission properties. Chiral inducing groups are introduced into thermally activated delayed fluorescence molecules to design thermally activated delayed fluorescence materials with CPL properties, and these materials are introduced into organic light-emitting diodes (OLEDs) as light-emitting layer materials. This is expected to prepare organic circularly polarized light-emitting diodes (CP OLEDs) and achieve efficient circularly polarized electroluminescence (CPEL). This organic small molecule has a single structure, a determined molecular weight, and a simple purification step, and can be used in organic optoelectronic devices including organic light-emitting diodes. Summary of the Invention

[0004] To overcome the shortcomings and deficiencies of the prior art, the present invention provides a benzophenone derivative organic luminescent material and a method for preparing the same. The benzophenone derivative organic luminescent material of the present invention utilizes a benzophenone derivative as a backbone unit. By varying the chiral group, its heterocyclic atoms, and the number of connecting units on either side, the molecular weight, π conjugation, and circularly polarized luminescence properties of the material can be adjusted. This type of organic luminescent material effectively addresses the problem of preparing high-efficiency circularly polarized luminescent materials, thereby improving the performance of such devices. The synthesis and purification processes for this type of material are simple, with high yields, making it suitable for large-scale production. Organic electroluminescent devices prepared using the luminescent material of the present invention, which exhibits both circularly polarized luminescence and thermally activated delayed fluorescence emission, as the luminescent layer exhibit high brightness and external quantum efficiency, meeting practical requirements.

[0005] The purpose of the present invention is achieved through the following technical solutions:

[0006] A benzophenone derivative organic light-emitting material, the molecular formula of which is shown in formula (I),

[0007]

[0008] in,

[0009] The Ar1 unit is selected from one or more aromatic heterocycles or aromatic rings, and the connection form between the multiple aromatic heterocycles or aromatic rings is selected from fused ring connection, linked ring connection or a combination of the two;

[0010] The raw material (II) of the Ar1 unit has the following structure:

[0011]

[0012] The Y unit is a benzophenone derivative, and the Y unit is independently selected from the following structures:

[0013]

[0014] Wherein, X is a C or N atom;

[0015] The raw material (III) of the Y unit has the following structure:

[0016]

[0017] Wherein, M and G are independently selected from fluorine, chlorine, bromine and iodine;

[0018] The D unit is selected from one or more combinations of vinylene, ethynylene, aromatic rings composed of carbon and hydrogen atoms, aromatic heterocycles composed of carbon, nitrogen, and hydrogen atoms, aromatic heterocycles composed of carbon, nitrogen, oxygen, and hydrogen atoms, aromatic heterocycles composed of carbon, nitrogen, sulfur, and hydrogen atoms, aromatic heterocycles composed of carbon, nitrogen, silicon, and hydrogen atoms, alkyl-substituted conjugated units, and alkoxy-substituted conjugated units;

[0019] The raw material (IV) of the D unit is a D unit containing active hydrogen and has the following structure:

[0020]

[0021] Among them, -H is active hydrogen.

[0022] Furthermore, the Ar1 unit is selected from the following structures:

[0023]

[0024] Wherein, Q is selected from alkyl or aromatic groups, and the alkyl group is selected from C3-C 22 Cyclic alkyl, C3-C 22 Straight chain alkyl or C3-C 22 branched alkyl;

[0025] The aromatic group is selected from one or more aromatic heterocycles or aromatic rings, and the connection form between the multiple aromatic heterocycles or aromatic rings is selected from fused ring connection, linked ring connection or a combination of the two.

[0026] Furthermore, the D unit is selected from a carbazole unit, a fluorene unit, a thiazole unit, a thiophene unit, a spirofluorene unit, an indolefluorene unit, a benzodithiophene unit, a thienocyclopentadiene unit, a thienopyrrolidone unit, a quinoxalinone unit, a quinoxaline unit, a pyrrole unit, a pyridine unit, a furan unit, a silylfluorene unit, or a derivative of the above optional objects, or a combination of one or more of the above optional objects.

[0027] Furthermore, the benzophenone derivative organic light-emitting material is independently selected from the following structures:

[0028]

[0029] Another object of the present invention is to provide a method for preparing the above-mentioned benzophenone derivative organic light-emitting material, wherein the method for preparing the benzophenone derivative organic light-emitting material comprises the following steps:

[0030] S1. Dissolving the raw material (II), the raw material (III) and potassium carbonate in a solvent under an inert gas atmosphere, heating to reflux, and stirring to react; after the reaction is completed and cooled, the resulting mixture is extracted and the solvent is removed by distillation under reduced pressure, and the crude product is purified and dried to obtain an intermediate product A;

[0031] S2. Add the intermediate product A and the raw material (IV) to a solvent, add palladium acetate, tri-tert-butyl phosphine and potassium carbonate, heat to reflux, and stir to react; after the reaction is completed and cooled, pour the mixed solution into water, extract and dry the organic phase, remove the solvent after separation, separate and purify, and sublime after drying to obtain the target product.

[0032] Furthermore, the molar ratio of the raw material (II) to the raw material (III) is 1:0.5 to 1:2.

[0033] Furthermore, the molar ratio of the intermediate product A to the raw material (IV) is 1:0.5 to 1:2.5.

[0034] Furthermore, the solvent is selected from one or more of water, aromatic solvents, halogenated hydrocarbon solvents, alcohol solvents, ether solvents, ester solvents, ketone solvents, and amide solvents.

[0035] Specifically, the above-mentioned solvent is preferably a common polar solvent in the art, which can be, but is not limited to, tetrahydrofuran, methyltetrahydrofuran, dichloromethane, chloroform, ethyl acetate, propyl acetate, butyl acetate, ethyl propionate, propyl propionate, butyl propionate, methyl methacrylate, ethyl methacrylate, propyl methacrylate, toluene, xylene, trimethylbenzene, chlorobenzene, dichlorobenzene, trichlorobenzene, methanol, ethanol, propanol, ethylene glycol, isobutanol, propylene glycol, acetonitrile, formic acid, acetic acid, propionic acid, trifluoroacetic acid, dimethylformamide, dimethylacetamide, dimethyl sulfoxide, dimethylacetamide, acetone, butanone, cyclohexanone, methyl butanone, methyl ether, ethyl ether, propyl ether, pyridine, phenol, N-methylpyrrolidone, ethylene glycol monomethyl ether, triethylene glycol monomethyl ether, triethylamine, tetramethylethylenediamine, trioctylamine, aniline, hexamethylphosphoric acid triamine; and a mixture of two or more of the above-mentioned substances in any proportion.

[0036] Another object of the present invention is to provide the use of the above-mentioned benzophenone derivative organic light-emitting material in an organic electroluminescent device.

[0037] The beneficial effects of the present invention are:

[0038] 1. The benzophenone derivative organic light-emitting material obtained in the present invention has the advantages of circularly polarized luminescence properties, thermally activated delayed properties and high fluorescence quantum yield.

[0039] 2. The benzophenone derivative organic light-emitting material obtained in the present invention has a single structure, a certain molecular weight, is easy to purify, has good reproducibility in multiple syntheses, and is convenient for studying the relationship between structure and performance.

[0040] 3. The benzophenone derivative organic luminescent material obtained in the present invention has a low biochemical temperature and decomposition temperature, and a stable film morphology.

[0041] 4. The benzophenone derivative organic light-emitting material obtained in the present invention can effectively regulate the conjugation length and luminescent color of the material by changing the connected chemical structure.

[0042] 5. The benzophenone derivative organic light-emitting material obtained in the present invention can further improve the physical properties of the material and the performance of the optoelectronic device based thereon by changing the modifying groups on the aromatic structure. BRIEF DESCRIPTION OF THE DRAWINGS

[0043] Figure 1 This is the spectrum of the organic electroluminescent blue light device of Application Example 1.

[0044] Figure 2 This is a graph showing the relationship between current density, voltage and brightness of the organic electroluminescent blue light emitting device of Application Example 1.

[0045] Figure 3 This is a graph showing the relationship between external quantum efficiency and current density of the organic electroluminescent blue light emitting device of Application Example 1.

[0046] Figure 4 This is the circularly polarized luminescence spectrum of the organic electroluminescent blue light emitting device of Application Example 1.

[0047] Figure 5 This is a graph showing the relationship between external quantum efficiency and current density of the organic electroluminescent blue light emitting device of comparative application example 1. DETAILED DESCRIPTION

[0048] In order to more clearly illustrate the technical solution of the present invention, the following examples are listed. Unless otherwise stated, the raw materials, reactions and post-processing methods shown in the examples are all common raw materials on the market and technical means well known to those skilled in the art. The present invention will be further described in detail below in conjunction with specific examples, but the embodiments of the present invention are not limited thereto.

[0049] Example 1: Preparation of a benzophenone derivative organic light-emitting material

[0050] (1) Synthesis of intermediates

[0051]

[0052] Monomer 1 (5 mmol, 1.09 g), monomer 2 (5 mmol, 1.48 g), and potassium carbonate (K2CO3) (7.5 mmol, 1.04 g) were dissolved in 50 mL of ultra-dry N,N-dimethylformamide under argon, heated to 80°C and refluxed with vigorous stirring for 12 hours. After the reaction was completed, the mixture was cooled to approximately 25°C and extracted three times with dichloromethane and deionized water, respectively. The solvent was then removed by rotary distillation under reduced pressure. The crude product was then purified by column chromatography and dried under vacuum to obtain intermediate product A1 as a white solid in a 45.8% yield (1.08 g).

[0053] (2) Synthesis of target product

[0054]

[0055] 3 mmol of Al and 3.5 mmol of acridine were added to 100 mL of toluene. 60 mg of palladium acetate, 0.5 mmol of tri-tert-butyl phosphine, 0.11 g of tri-tert-butyl phosphine, and 0.75 g of potassium carbonate were also added. The mixture was stirred and reacted under reflux for 24 hours. After cooling, the mixture was poured into 200 mL of water, and the product was extracted with dichloromethane. The organic phase was dried over anhydrous magnesium sulfate, separated, and the solvent removed. The product was purified by silica gel chromatography to obtain a white solid, which was then dried and sublimed under vacuum to obtain the target product M1. The yield of the target product M1 was 70%.

[0056] Example 2: Preparation of a benzophenone derivative organic light-emitting material

[0057] (1) Synthesis of intermediates

[0058]

[0059] Monomer 1 (5 mmol, 1.09 g), monomer 3 (5 mmol, 1.47 g), and potassium carbonate (K2CO3) (7.5 mmol, 1.04 g) were dissolved in 50 mL of ultra-dry N,N-dimethylformamide under argon, heated to 80°C and refluxed with vigorous stirring for 12 hours. After the reaction was completed, the mixture was cooled to approximately 25°C and extracted three times with dichloromethane and deionized water, respectively. The solvent was then removed by rotary distillation under reduced pressure. The crude product was then purified by column chromatography and dried under vacuum to afford intermediate A2 as a white solid in a 45.8% yield (1.08 g).

[0060] (2) Synthesis of target product

[0061]

[0062] 3 mmol of A2 and 3.5 mmol of acridine were added to 100 mL of toluene. 60 mg of palladium acetate, 0.5 mmol of tri-tert-butyl phosphine, 0.11 g of tri-tert-butyl phosphine, and 0.75 g of potassium carbonate were also added. The mixture was stirred and reacted under reflux for 24 hours. After cooling, the mixture was poured into 200 mL of water, and the product was extracted with dichloromethane. The organic phase was dried over anhydrous magnesium sulfate, separated, and the solvent removed. The product was purified by silica gel chromatography to obtain a white solid, which was then dried and sublimed under vacuum to obtain the target product M2. The yield of the target product M2 was 70%.

[0063] Example 3: Preparation of a benzophenone derivative organic light-emitting material

[0064] (1) Synthesis of intermediates

[0065]

[0066] Monomer 4 (5 mmol, 1.09 g), monomer 2 (5 mmol, 1.48 g), and potassium carbonate (K2CO3) (7.5 mmol, 1.04 g) were dissolved in 50 mL of ultra-dry N,N-dimethylformamide under argon, heated to 80°C and refluxed with vigorous stirring for 12 hours. After the reaction was completed, monitored by a microplate, the reactants were cooled to approximately 25°C. The resulting mixture was extracted three times with dichloromethane and deionized water, respectively, and the solvent was removed by rotary distillation under reduced pressure. The crude product was then purified by column chromatography and dried under vacuum to afford intermediate product A3 as a white solid in a 45.8% yield (1.08 g).

[0067] (2) Synthesis of target product

[0068]

[0069] 3 mmol of A3 and 3.5 mmol of acridine were added to 100 mL of toluene. 60 mg of palladium acetate, 0.5 mmol of tri-tert-butyl phosphine, 0.11 g of tri-tert-butyl phosphine, and 0.75 g of potassium carbonate were also added. The mixture was stirred and reacted under reflux for 24 hours. After cooling, the mixture was poured into 200 mL of water, and the product was extracted with dichloromethane. The organic phase was dried over anhydrous magnesium sulfate, separated, and the solvent removed. The product was purified by silica gel chromatography to obtain a white solid, which was then dried and sublimed under vacuum to obtain the target product M3. The yield of the target product M3 was 70%.

[0070] Example 4: Preparation of a benzophenone derivative organic light-emitting material

[0071] (1) Synthesis of intermediates

[0072]

[0073] Monomer 4 (5 mmol, 1.09 g), monomer 3 (5 mmol, 1.48 g), and potassium carbonate (K2CO3) (7.5 mmol, 1.04 g) were dissolved in 50 mL of ultra-dry N,N-dimethylformamide under argon, heated to 80°C and refluxed with vigorous stirring for 12 hours. After the reaction was completed, the mixture was cooled to approximately 25°C and extracted three times with dichloromethane and deionized water, respectively. The solvent was then removed by rotary distillation under reduced pressure. The crude product was then purified by column chromatography and dried under vacuum to afford intermediate product A4 as a white solid in a 45.8% yield (1.08 g).

[0074] (2) Synthesis of target product

[0075]

[0076] 3 mmol of A4 and 3.5 mmol of acridine were added to 100 mL of toluene. 60 mg of palladium acetate, 0.5 mmol of tri-tert-butyl phosphine, 0.11 g of tri-tert-butyl phosphine, and 0.75 g of potassium carbonate were also added. The mixture was stirred and reacted under reflux for 24 hours. After cooling, the mixture was poured into 200 mL of water, and the product was extracted with dichloromethane. The organic phase was dried over anhydrous magnesium sulfate, separated, and the solvent removed. The product was purified by silica gel chromatography to obtain a white solid, which was then dried and sublimed under vacuum to obtain the target product M4. The yield of the target product M4 was 72%.

[0077] Example 5: Preparation of a benzophenone derivative organic light-emitting material

[0078] (1) Synthesis of intermediates

[0079]

[0080] Monomer 1 (5 mmol, 1.09 g), monomer 5 (5 mmol, 1.74 g), and potassium carbonate (K2CO3) (7.5 mmol, 1.04 g) were dissolved in 50 mL of ultra-dry N,N-dimethylformamide under argon, heated to 80°C and refluxed with vigorous stirring for 12 hours. After the reaction was completed, monitored by a microplate, the reaction mixture was cooled to approximately 25°C. The resulting mixture was extracted three times with dichloromethane and deionized water, respectively, and the solvent was removed by rotary distillation under reduced pressure. The crude product was then purified by column chromatography and dried under vacuum to obtain intermediate A5 as a white solid in a 40.2% yield (1.20 g).

[0081] (2) Synthesis of target product

[0082]

[0083] 3 mmol of A5 and 3.5 mmol of acridine were added to 100 mL of toluene. 60 mg of palladium acetate, 0.5 mmol of tri-tert-butyl phosphine, 0.11 g of tri-tert-butyl phosphine, and 0.75 g of potassium carbonate were also added. The mixture was stirred and reacted under reflux for 24 hours. After cooling, the mixture was poured into 200 mL of water, and the product was extracted with dichloromethane. The organic phase was dried over anhydrous magnesium sulfate, separated, and the solvent removed. The product was purified by silica gel chromatography to obtain a white solid, which was then dried and sublimed under vacuum to obtain the target product M5. The yield of the target product M5 was 71%.

[0084] Example 6: Preparation of a benzophenone derivative organic light-emitting material

[0085] (1) Synthesis of intermediates

[0086]

[0087] Monomer 1 (5 mmol, 1.09 g), monomer 6 (5 mmol, 1.72 g), and potassium carbonate (K2CO3) (7.5 mmol, 1.04 g) were dissolved in 50 mL of ultra-dry N,N-dimethylformamide under argon, heated to 80°C and refluxed with vigorous stirring for 12 hours. After the reaction was completed, monitored by a microplate, the reaction mixture was cooled to approximately 25°C. The resulting mixture was extracted three times with dichloromethane and deionized water, respectively, and the solvent was removed by rotary distillation under reduced pressure. The crude product was then purified by column chromatography and dried under vacuum to obtain intermediate product A6 as a white solid in a 38.8% yield (1.17 g).

[0088] (2) Synthesis of target product

[0089]

[0090] 3 mmol of A6 and 3.5 mmol of acridine were added to 100 mL of toluene. 60 mg of palladium acetate, 0.5 mmol of tri-tert-butyl phosphine, 0.11 g of tri-tert-butyl phosphine, and 0.75 g of potassium carbonate were also added. The mixture was stirred and reacted under reflux for 24 hours. After cooling, the mixture was poured into 200 mL of water, and the product was extracted with dichloromethane. The organic phase was dried over anhydrous magnesium sulfate, separated, and the solvent removed. The product was purified by silica gel chromatography to obtain a white solid, which was then dried and sublimed under vacuum to obtain the target product M6. The yield of the target product M6 was 69%.

[0091] Example 7: Preparation of a benzophenone derivative organic light-emitting material

[0092] (1) Synthesis of intermediates

[0093]

[0094] Monomer 4 (5 mmol, 1.09 g), monomer 5 (5 mmol, 1.73 g), and potassium carbonate (K2CO3) (7.5 mmol, 1.04 g) were dissolved in 50 mL of ultra-dry N,N-dimethylformamide under argon, heated to 80°C and refluxed with vigorous stirring for 12 hours. After the reaction was completed, monitored by a microplate, the reaction mixture was cooled to approximately 25°C. The resulting mixture was extracted three times with dichloromethane and deionized water, respectively, and the solvent was removed by rotary distillation under reduced pressure. The crude product was then purified by column chromatography and dried under vacuum to afford product A7 as a white solid in a 41.0% yield (1.23 g).

[0095] (2) Synthesis of target product

[0096]

[0097] 3 mmol of A7 and 3.5 mmol of acridine were added to 100 mL of toluene. 60 mg of palladium acetate, 0.5 mmol of tri-tert-butyl phosphine, 0.11 g of tri-tert-butyl phosphine, and 0.75 g of potassium carbonate were also added. The mixture was stirred and reacted under reflux for 24 hours. After cooling, the mixture was poured into 200 mL of water, and the product was extracted with dichloromethane. The organic phase was dried over anhydrous magnesium sulfate, separated, and the solvent removed. The product was purified by silica gel chromatography to obtain a white solid, which was then dried and sublimed under vacuum to obtain the target product M7. The yield of the target product M7 was 70%.

[0098] Example 8: Preparation of a benzophenone derivative organic light-emitting material

[0099] (1) Synthesis of intermediates

[0100]

[0101] Monomer 4 (5 mmol, 1.09 g), monomer 6 (5 mmol, 1.72 g), and potassium carbonate (K2CO3) (7.5 mmol, 1.04 g) were dissolved in 50 mL of ultra-dry N,N-dimethylformamide under argon, heated to 80°C and refluxed with vigorous stirring for 12 hours. After the reaction was completed, monitored by a microplate, the reaction mixture was cooled to approximately 25°C. The resulting mixture was extracted three times with dichloromethane and deionized water, respectively, and the solvent was removed by rotary distillation under reduced pressure. The crude product was then purified by column chromatography and dried under vacuum to afford intermediate product A8 as a white solid in a 40.1% yield (1.21 g).

[0102] (2) Synthesis of target product

[0103]

[0104] 3 mmol of A8 and 3.5 mmol of acridine were added to 100 mL of toluene. 60 mg of palladium acetate, 0.5 mmol of tri-tert-butyl phosphine, 0.11 g of tri-tert-butyl phosphine, and 0.75 g of potassium carbonate were also added. The mixture was stirred and reacted under reflux for 24 hours. After cooling, the mixture was poured into 200 mL of water, and the product was extracted with dichloromethane. The organic phase was dried over anhydrous magnesium sulfate, separated, and the solvent removed. The product was purified by silica gel chromatography to obtain a white solid, which was then dried and sublimed under vacuum to obtain the target product M8. The yield of the target product M8 was 73%.

[0105] Example 9: Preparation of a benzophenone derivative organic light-emitting material

[0106]

[0107] Referring to step (2) of Example 1, 10H-phenoxazine was used instead of acridine to synthesize the target product M9. The yield of the target product M9 was 61%.

[0108] Example 10: Preparation of a benzophenone derivative organic light-emitting material

[0109]

[0110] Referring to step (2) of Example 2, 10H-phenoxazine was used instead of acridine to synthesize the target product M10. The yield of the target product M10 was 60%.

[0111] Example 11: Preparation of a benzophenone derivative organic light-emitting material

[0112]

[0113] Referring to step (2) of Example 3, 10H-phenoxazine was used instead of acridine to synthesize the target product M11. The yield of the target product M11 was 67%.

[0114] Example 12: Preparation of a Benzophenone Derivative Organic Luminescent Material

[0115]

[0116] Referring to step (2) of Example 4, target product M12 was synthesized using 10H-phenoxazine instead of acridine. The yield of compound M12 was 72%.

[0117] Example 13: Preparation of a Benzophenone Derivative Organic Luminescent Material

[0118]

[0119] Referring to step (2) of Example 5, 10H-phenoxazine was used instead of acridine to synthesize the target product M13. The yield of the target product M13 was 71%.

[0120] Example 14: Preparation of a Benzophenone Derivative Organic Luminescent Material

[0121]

[0122] Referring to step (2) of Example 6, 10H-phenoxazine was used instead of acridine to synthesize the target product M14. The yield of the target product M14 was 69%.

[0123] Example 15: Preparation of a Benzophenone Derivative Organic Luminescent Material

[0124]

[0125] Referring to step (2) of Example 7, target product M15 was synthesized using 10H-phenoxazine instead of acridine. The yield of target product M15 was 70%.

[0126] Example 16: Preparation of a Benzophenone Derivative Organic Luminescent Material

[0127]

[0128] Referring to step (2) of Example 8, 10H-phenoxazine was used instead of acridine to synthesize the target product M16. The yield of the target product M16 was 73%.

[0129] Comparative Example 1

[0130] A method for preparing an organic light-emitting compound derived from a benzophenone derivative. The difference between this comparative example and Example 1 is that the intermediate product A1 in step (2) of Example 1 is replaced with achiral brominated benzophenone. The prepared organic light-emitting compound N1 is shown in the figure below. The other steps and materials are the same as in Example 1.

[0131]

[0132] The target product M1 in Example 1 of the present invention and the compound N1 prepared in Comparative Example 1 were applied to the light-emitting layer of an OLED device to further illustrate the actual technical effects of the present invention.

[0133] Application Example 1

[0134] In Example 1 of the present invention, M1 is used as the guest material of the light-emitting layer, and the structure of the prepared device OLED is: ITO / HATCN (5nm) / TAPC (30nm) / TCTA (10nm) / mCBP (10nm) / M1-doped PPF (M1 accounts for 15wt% of this layer) (20nm) / DPEPO (10nm) / TmPyPB (40nm) / LiF (1nm) / Al (150nm).

[0135] Figure 1 This is the spectrum of the organic electroluminescent blue light emitting device of Application Example 1; Figure 2 This is a graph showing the relationship between current density, voltage and brightness of the organic electroluminescent blue light emitting device of Application Example 1; Figure 3 This is a graph showing the relationship between external quantum efficiency and current density of the organic electroluminescent blue light emitting device of Application Example 1; Figure 4 This is the circularly polarized luminescence spectrum of the organic electroluminescent blue light device of Application Example 1; this indicates that a luminescent material having both circularly polarized luminescence and thermally activated delayed fluorescence emission properties has been successfully prepared.

[0136] Comparative Application Example 1

[0137] The compound prepared in Comparative Example 1 was used as the guest material of the light-emitting layer, and the structure of the prepared device OLED was: ITO / HATCN (5nm) / TAPC (30nm) / TCTA (10nm) / mCBP (10nm) / N1-doped PPF (N1 accounts for 15wt% of this layer) (20nm) / DPEPO (10nm) / TmPyPB (40nm) / LiF (1nm) / Al (150nm). Figure 5 This is a diagram showing the relationship between external quantum efficiency and current density for comparative application example 1.

[0138] Test Example 1

[0139] In Application Example 1 and Comparative Application Example 1, OLED devices were prepared respectively, and a positive bias voltage was applied between the ITO and metal electrodes, and the characteristics of the devices were tested at different currents.

[0140] The test results of the organic electroluminescent device prepared above are as follows:

[0141] Table 1 Device application example 1 and comparative application example 1 data

[0142]

[0143] From Table 1 and Figure 1-4 It can be seen that adding the M1 compound containing a chiral group as the light-emitting layer in the OLED device can achieve high brightness and low device roll-off in the device, improve the device's ability to balance carriers, thereby improving the efficiency and stability of the device, and thus achieving high-efficiency performance in the organic electroluminescent device. In contrast, the device prepared from N1 in Application Example 1 has no circular polarization phenomenon and cannot achieve the same technical effect as Application Example 1.

[0144] It will be apparent to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above and that the invention can be embodied in other specific forms without departing from the spirit or essential characteristics of the invention. Therefore, the embodiments should be considered in all respects as illustrative and non-restrictive, and the scope of the invention is defined by the appended claims rather than the foregoing description, and it is intended that all variations that come within the meaning and range of equivalents of the claims be embraced therein.

[0145] In addition, it should be understood that although this specification is described in terms of implementation methods, not every implementation method contains only one independent technical solution. This narrative method of the specification is only for the sake of clarity. Those skilled in the art should regard the specification as a whole. The technical solutions in each embodiment can also be appropriately combined to form other implementation methods that can be understood by those skilled in the art.

Claims

1. A benzophenone derivative organic light-emitting material, characterized in that: Its structure is: 。 2. The method for preparing the benzophenone derivative organic light-emitting material according to claim 1, characterized in that: The reaction equation is: 。

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