Indole-containing polycyclic bis-boron azapinophanes and organic electroluminescent devices thereof
By introducing an indole-derived unsaturated five-membered ring structure into MR-TADF materials and introducing substituents around the molecular backbone, the aggregation problem of MR-TADF materials was solved, exciton utilization efficiency and device stability were improved, and a high-efficiency, long-life organic electroluminescent device was realized.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- JILIN YUANHE ELECTRONICS MATERIALS CO LTD
- Filing Date
- 2026-03-26
- Publication Date
- 2026-06-23
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Figure QLYQS_1 
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Abstract
Description
Technical Field
[0001] This invention belongs to the field of organic electroluminescent materials technology, specifically relating to an indole-containing polycyclic diboron nitrogen compound and its organic electroluminescent device. Background Technology
[0002] Organic light-emitting diodes (OLEDs), as the core technology of the third generation of displays, are widely used in various terminal display products due to their advantages such as self-illumination, flexibility and ultra-thinness, and high color gamut. They also have broad prospects in the lighting field. The core performance of their devices is directly determined by the organic functional layer materials, and the research and development of high-performance OLED materials is the key to promoting industrial upgrading.
[0003] OLED light-emitting materials have undergone three generations of iteration, all of which have inherent defects: the first generation of fluorescent materials has an exciton utilization rate of only 25%, which is inefficient; the second generation of phosphorescent materials relies on precious metals, which is costly; the third generation of traditional DA-type TADF materials has a high exciton utilization rate and low cost, but still has problems such as wide emission spectrum and poor color purity.
[0004] In recent years, multiple resonance thermo-induced delayed fluorescence (MR-TADF) materials have shown great potential in realizing high-efficiency, high-color-purity OLEDs due to their high luminous efficiency and narrow emission half-width. Systems with two or more boron atoms, in particular, contribute to improving the reverse intersystem crossing rate due to their strong resonance effect. However, these systems often exhibit a severe aggregation tendency due to their large fused-ring molecular backbone, easily leading to problems such as fluorescence quenching, exciton annihilation, and shortened lifetime, which greatly restricts the improvement of device performance. Simultaneously, the poor solubility caused by the large fused-ring molecular backbone is also detrimental to material purification, affecting the mass production of materials. Therefore, suppressing molecular aggregation and improving solubility through molecular structure design is a problem that needs to be solved for application purposes, and it is also the starting point of this invention. Summary of the Invention
[0005] To address the problems existing in the background art, the present invention provides a polycyclic diboron nitrogen compound containing indole, the structure of which is shown in any one of general formulas (1) to (3): ; Among them, ring A is independently selected from C6-C. 12 aryl or C5-C 12 The heteroaryl groups; rings B are each independently selected from C6-C6. 12 The aryl group; X1 is selected from O, S, Se, NR3, CR4R5; X2 is selected from single bond, O, S, Se, NR3, CR4R5; Indicates whether a bond relationship exists or not; R is independently selected from hydrogen, deuterium, cyano, trifluoromethyl, deuterated or undeuterated C1-C atoms. 10 Alkyl, substituted or unsubstituted C6-C 18 Arylsilyl, substituted or unsubstituted C6-C 18 Aryl, substituted or unsubstituted C5-C 18 Heteroaryl, substituted or unsubstituted diarylamine, where n is from 1 to the largest substitution site in the ring; R1 and R2 are each independently selected from hydrogen, deuterium, cyano, trifluoromethyl, deuterated or undeuterated C1-C atoms. 10 Alkyl, substituted or unsubstituted C6-C 12 Aryl or C5-C 12 Heteroaryl, substituted or unsubstituted diarylamine; R1 and R2 can be linked together to additionally form alicyclic or aromatic monocyclic or polycyclic compounds; R3 is independently selected from substituted or unsubstituted phenyl groups; R4 and R5 are independently selected from deuterated or undeuterated C1-C4 alkyl groups, substituted or unsubstituted phenyl groups; R4 and R5 can be linked together to additionally form alicyclic or aromatic monocyclic or polycyclic groups. When substitutions are present, the substituents are independently selected from deuterium, cyano, trifluoromethyl, deuterated or undeuterated methyl, deuterated or undeuterated isopropyl, deuterated or undeuterated tert-butyl, deuterated or undeuterated phenyl; the heteroatoms are N, O, S, and Se.
[0006] As a preferred embodiment of the present invention, X1 is selected from O, S, and NR3.
[0007] As a preferred embodiment of the present invention, X2 is selected from single bonds, O, S, and NR3.
[0008] As a preferred embodiment of the present invention, R is independently selected from hydrogen atoms, deuterium atoms, deuterated or undeuterated C1-C4 alkyl groups, substituted or unsubstituted C6-C groups. 12 Arylsilyl, substituted or unsubstituted C6-C 12 Aryl, substituted or unsubstituted C5-C 12 Heteroaryl, substituted or unsubstituted diarylamine.
[0009] Preferably, R1 and R2 are each independently selected from hydrogen atoms, deuterium atoms, deuterated or undeuterated C1-C4 alkyl groups, substituted or unsubstituted C6-C groups. 12 Aryl or C5-C 12 Mixed aromatic compounds.
[0010] More preferably, the indole-containing polycyclic diboron nitrogen compound of the present invention is selected from any one of the following chemical structures: ; ; ; ; ; ; ; ; ; .
[0011] A second aspect of the present invention provides an organic electroluminescent device, the organic electroluminescent device comprising a cathode layer, an anode layer and an organic functional layer therebetween; the organic functional layer comprising a hole injection layer, a hole transport layer, a light-emitting layer, an electron transport layer, and an electron injection layer, wherein the light-emitting layer contains at least one of the indole-containing polycyclic diboron nitrogen compounds of the present invention.
[0012] Preferably, the light-emitting layer comprises a host material and a guest material, wherein the guest material comprises at least one of the indole-containing polycyclic diboron nitrogen compounds.
[0013] Preferably, the organic electroluminescent device is used to manufacture display devices, lighting sources, signal lights, and signs, wherein the display devices include mobile phone displays, computer displays, television displays, smartwatch displays, smart car display panels, and VR or AR helmet displays.
[0014] The beneficial effects of this invention are as follows: This invention introduces substituents into the unsaturated five-membered ring-derived structure (indole-derived structure) of an MR-TADF system containing two boron atoms, causing slight distortion of the molecular skeleton and introducing appropriate steric hindrance. Molecular distortion and steric hindrance weaken intermolecular π-π stacking interactions, thereby suppressing fluorescence quenching and triplet exciton annihilation. Simultaneously, molecular distortion enhances spin-orbit coupling, improving the triplet-to-singlet conversion efficiency and increasing the reverse intersystem crossing rate, thus achieving higher exciton utilization efficiency and a smaller efficiency roll-off. Substituents improve solubility, enhancing the feasibility of mass synthesis. The steric hindrance effectively suppresses crystallization tendency, resulting in excellent uniformity and morphological stability during vapor deposition. The stable amorphous film reduces charge traps and defects, lowers leakage current and short-circuit risks, significantly improves device stability and reliability, and extends the device's safe operating life. Detailed Implementation
[0015] Before providing a detailed description of the invention, it should be understood that the terminology used in this specification is for describing specific embodiments only and is not intended to limit the scope of the invention. The scope of the invention should be defined only by the scope of the appended claims. Unless otherwise expressly stated, all technical and scientific terms used in this specification have the same meaning as commonly understood by one of ordinary skill in the art.
[0016] The technical solution of the present invention will be further illustrated below through specific embodiments. Those skilled in the art should understand that the embodiments described are merely illustrative of the invention and should not be considered as specific limitations thereof. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without inventive effort are within the protection scope of the present invention.
[0017] Synthesis Examples The present invention does not impose any particular restrictions on the source of the raw materials used in the following embodiments, which can be commercially available products or prepared by methods known to those skilled in the art.
[0018] Example 1: Synthesis of Compound 1 ; Synthesis of 1-3: Under a nitrogen atmosphere, 1-1 (2.69 g, 10.0 mmol), 1-2 (3.57 g, 10.0 mmol), and cesium carbonate (8.15 g, 25.0 mmol) were added to 100 mL of DMF and reacted overnight at 120 °C. Heating was stopped, and after cooling to room temperature, 100 mL of water was added and stirred for 10 min. A large amount of solid precipitated out. The solid was filtered, and the filter cake was washed with ethanol for 2 h. After cooling, the solid was filtered again to obtain 1-3 (4.91 g, 81%). The molecular weight determined by mass spectrometry was 606.21 (theoretical value: 606.35). Synthesis of 1-5: Under a nitrogen atmosphere, 1-3 (6.06 g, 10.0 mmol), 1-4 (1.49 g, 10.0 mmol), tris(dibenzylacetone)dipalladium (Pd2(dba)3) (175 mg, 0.2 mmol), 2-biscyclohexylphosphine-2',4',6'-triisopropylbiphenyl (X-phos) (114 mg, 0.25 mmol), and sodium tert-butoxide (1.06 g, 11.0 mmol) were added to 50 mL of toluene. The reaction mixture was heated to 90 °C and stirred for 8 h. After the reaction was complete, the reaction mixture was cooled to room temperature. Add 50 mL of deionized water to the reaction system, collect the organic phase by separation, dry with anhydrous sodium sulfate, remove the solvent of the organic layer by rotary evaporation, purify the crude product by column chromatography, and recrystallize to obtain 1-5 (5.34 g, 85%), with a molecular weight determined by mass spectrometry of 627.53 (theoretical value: 627.67). Synthesis of 1-7: Under a nitrogen atmosphere, 1-6 (1.50 g, 10.0 mmol), 1-2 (3.93 g, 11 mmol), and potassium tert-butoxide (2.24 g, 20.0 mmol) were added to 60 mL of DMF. The reaction system was heated to 120 °C and stirred for 12 h. After the reaction was complete, the reaction mixture was cooled to room temperature. 60 mL of deionized water was added to the reaction system, and the mixture was extracted with dichloromethane and water. The organic phase was concentrated, purified by column chromatography, and recrystallized to obtain 1-7 (4.04 g, 83%). The molecular weight determined by mass spectrometry was 487.11 (theoretical value: 487.22). The synthesis methods of 1-8 and 1-5 are the same, the difference is that 1-7 replaces 1-3 and 1-5 replaces 1-4. The molecular mass determined by mass spectrometry analysis is 986.84 (theoretical value: 986.98). Synthesis of Compound 1: 1-8 (4.93 g, 5.0 mmol) was dissolved in 150 mL of tert-butylbenzene under a nitrogen atmosphere. tIn a nitrogen atmosphere at 0°C, 7.5 mL of a pentane solution of tert-butyllithium (t-BuLi) (1.6 M) was slowly added, and the mixture was stirred at 60°C for 2 h. Boron tribromide (BBr3) (3.01 g, 12.0 mmol) was then added, and the reaction mixture was stirred at room temperature for 1 h. N,N-diisopropylethylamine (DIEA) (4.63 g, 36.0 mmol) was then added, and the mixture was reacted at room temperature for 1 h. The mixture was then heated to 130°C and stirred for 6 h. The reaction mixture was then cooled to room temperature, and methanol was added to remove residual boron tribromide. The mixture was separated, extracted with water and dichloromethane, and the organic phase was collected by liquid-liquid extraction. After drying with anhydrous sodium sulfate, the solvent in the organic layer was removed by rotary evaporation. The crude product was purified by column chromatography, and recrystallized to give compound 1 (2.03 g, 48%). The molecular weight determined by mass spectrometry was 844.65 (theoretical value: 844.76).
[0019] Example 2: Synthesis of Compound 4 ; The synthesis methods for 4-2 and 1-7 are the same, except that 4-1 is used instead of 1-2. The molecular mass determined by mass spectrometry analysis is 521.52 (theoretical value: 521.66). The synthesis method of compound 4-4 is the same as that of compound 1, except that 1-7 is replaced by 4-2. The other steps are the same. The molecular mass determined by mass spectrometry is 879.07 (theoretical value: 879.20). Synthesis of Compound 4: Under a nitrogen atmosphere, 4-4 (2.64 g, 3.0 mmol), 1,3-bis(2,6-diisopropylphenyl)imidazolium chloride (IPrHCl) (53 mg, 0.12 mmol), palladium(II) acetate (13.6 mg, 0.06 mmol), and potassium carbonate (0.83 g, 4.2 mmol) were added to 40 mL of N,N-dimethylacetamide (DMAc). The reaction mixture was heated to 160 °C and stirred for 12 h. After the reaction was complete, the reaction mixture was cooled to room temperature. The precipitated solid was collected by filtration, washed with acetone, and the crude product was purified by column chromatography. Recrystallization yielded Compound 4 (1.82 g, 72%), with a molecular weight determined by mass spectrometry of 842.60 (theoretical value: 842.74).
[0020] Example 3: Synthesis of Compound 10 ; The synthesis methods for 10-2 and 1-5 are the same, except that 10-1 is used instead of 1-4. The molecular mass determined by mass spectrometry is 829.82 (theoretical value: 829.96). The synthesis methods for 10-4 and 1-7 are the same, except that 10-3 is used instead of 1-6. The molecular mass determined by mass spectrometry is 430.95 (theoretical value: 431.11). Compound 10 was synthesized using the same method as compound 1, except that 1-7 was replaced with 10-4 and 1-5 was replaced with 10-2. The other steps were the same. The molecular mass determined by mass spectrometry was 990.83 (theoretical value: 990.94).
[0021] Example 4: Synthesis of Compound 15 ; Synthesis of Compound 15: Under a nitrogen atmosphere, Compound 1 (4.22 g, 5.0 mmol), 25 mL of heavy water, and 10 mL of toluene were added to a 100 mL three-necked flask and stirred at 120 °C for 24 h. After cooling the reaction system to room temperature, it was extracted three times with dichloromethane and water. After separation, the organic phase was used to remove the solvent using a rotary evaporator to obtain the crude product. The crude product was purified by column chromatography to obtain Compound 15 (3.52 g, 78%), with a molecular weight determined by mass spectrometry of 903.00 (theoretical value: 903.11).
[0022] Example 5: Synthesis of Compound 21 ; Synthesis of 21-3: Under a nitrogen atmosphere, 21-1 (2.45 g, 10.0 mmol), 21-2 (1.90 g, 11.0 mmol), tris(dibenzylacetone)palladium (Pd2(dba)3) (175 mg, 0.2 mmol), a 10% (w / w) toluene solution of tri-tert-butylphosphine (0.80 g, 0.4 mmol), and sodium tert-butoxide (2.89 g, 30.0 mmol) were added to 80 mL of toluene. The mixture was heated to reflux for 12 h and then cooled to room temperature. 60 mL of deionized water was added to the reaction system, the organic phase was collected by separation, dried with anhydrous sodium sulfate, the solvent in the organic layer was removed by rotary evaporation, the crude product was purified by column chromatography, and recrystallized to obtain 21-3 (42.8 g, 83%), the molecular weight determined by mass spectrometry was 337.29 (theoretical value: 337.42); The synthesis methods for 21-4 and 1-7 are the same, except that 1-6 is replaced by 21-3. The molecular mass determined by mass spectrometry is 674.30 (theoretical value: 674.42). Compound 21 was synthesized using the same method as compound 1, except that 21-4 was used instead of 1-7. The other steps were the same. The molecular mass determined by mass spectrometry was 1031.83 (theoretical value: 1031.96).
[0023] Example 6: Synthesis of Compound 32 ; Synthesis of 32-3: Under a nitrogen atmosphere, 32-1 (2.75 g, 10.0 mmol), 32-2 (1.78 g, 10.0 mmol), palladium(II) acetate (Pd(OAc)2) (45 mg, 0.2 mmol), tricyclohexylphosphine (Cy3P) (168 mg, 0.6 mmol), and potassium carbonate (6.91 g, 50.0 mmol) were added to 100 mL of N-methylpyrrolidone (NMP) solvent. The mixture was stirred at 120 °C for 5 h. The resulting mixture was cooled to room temperature, and a portion of the NMP was distilled off under reduced pressure. The mixture was then extracted three times with dichloromethane and water. After separation, the organic phase was evaporated using a rotary evaporator to remove the solvent, yielding the crude product. After purification of the crude product by column chromatography, 32-3 (3.02 g, 78%) was obtained. The molecular weight determined by mass spectrometry was 7325.35 (theoretical value: 325.46). The synthesis method of 32-5 is the same as that of 1-5, except that 1-1 is replaced by 32-3. The other steps are the same. The molecular mass determined by mass spectrometry analysis is 687.64 (theoretical value: 683.78). The synthesis method of 32-7 is the same as that of 1-7. The difference is that 1-6 is replaced by 32-6. The molecular mass determined by mass spectrometry is 495.12 (theoretical value: 495.20). Compound 32 was synthesized using the same method as compound 1, except that 32-7 replaced 1-7 and 32-5 replaced 1-5. The other steps were the same. The molecular mass determined by mass spectrometry was 908.71 (theoretical value: 908.84).
[0024] Example 7: Synthesis of Compound 47 ; The synthesis method of 47-2 is the same as that of 1-7. The difference is that 1-6 is replaced by 47-1. The molecular mass determined by mass spectrometry is 487.02 (theoretical value: 487.19). Compound 47 was synthesized using the same method as compound 1, except that 1-7 was replaced with 47-2. All other steps were the same. The molecular mass determined by mass spectrometry was 844.59 (theoretical value: 844.73).
[0025] Example 8: Synthesis of Compound 52 ; The synthesis methods of 52-2 and 32-3 are the same, the difference being that 52-1 is used instead of 32-1. The molecular mass determined by mass spectrometry is 319.28 (theoretical value: 319.41). The synthesis methods of 52-4 and 1-5 are the same, except that 1-1 is replaced with 52-2. The other steps are the same. The molecular mass determined by mass spectrometry analysis is 677.59 (theoretical value: 677.73). Compound 52 was synthesized using the same method as compound 1, except that 10⁻⁴ replaced 1-7 and 5²⁻⁴ replaced 1-5. The other steps were the same. The molecular mass determined by mass spectrometry was 838.55 (theoretical value: 838.71).
[0026] Example 9: Synthesis of Compound 66 ; The synthesis methods of 66-2 and 1-7 are the same, except that 1-6 is replaced by 66-1. The molecular mass determined by mass spectrometry analysis is 503.13 (theoretical value: 503.28). Compound 66 was synthesized using the same method as compound 1, except that 66-2 replaced 1-7 and 32-5 replaced 1-5. The other steps were the same. The molecular mass determined by mass spectrometry was 916.80 (theoretical value: 916.93).
[0027] Example 10: Synthesis of Compound 72 ; The synthesis method of 72-3 is the same as that of 1-3, the difference being that 1-1 is replaced by 72-1. The molecular mass determined by mass spectrometry analysis is 370.41 (theoretical value: 370.54). The synthesis methods of 72-4 and 1-5 are the same, except that 72-3 is used instead of 1-4. The molecular mass determined by mass spectrometry is 848.86 (theoretical value: 848.97). The synthesis methods for 72-6 and 1-7 are the same, except that 72-5 is used instead of 1-6. The molecular mass determined by mass spectrometry is 447.05 (theoretical value: 447.17). Compound 72 was synthesized using the same method as compound 1, except that 72-6 replaced 1-7 and 72-4 replaced 1-5. The other steps were the same. The molecular mass determined by mass spectrometry was 1026.14 (theoretical value: 1026.01).
[0028] Example 11: Synthesis of Compound 95 ; The synthesis methods of 95-2 and 1-7 are the same, the difference is that 95-1 is used to replace 1-6. The molecular mass determined by mass spectrometry is 448.02 (theoretical value: 448.16). Compound 95 was synthesized using the same method as compound 1, except that 95-2 replaced 1-7 and 32-5 replaced 1-5. The other steps were the same. The molecular mass determined by mass spectrometry was 861.67 (theoretical value: 861.81).
[0029] Example 12: Synthesis of Compound 110 ; The synthesis methods of 110-2 and 1-7 are the same, except that 1-6 is replaced by 110-1. The molecular mass determined by mass spectrometry is 550.06 (theoretical value: 550.19). Compound 110 was synthesized using the same method as compound 1, except that 1-7 was replaced with 110-2. All other steps were the same. The molecular mass determined by mass spectrometry was 907.58 (theoretical value: 907.73).
[0030] Example 13: Synthesis of Compound 130 ; The synthesis methods of 130-2 and 21-3 are the same, the difference is that 1-4 is used to replace 21-1 and 130-1 is used to replace 21-2. The molecular mass determined by mass spectrometry is 253.22 (theoretical value: 253.39). The synthesis method of 130-3 is the same as that of 1-3, the difference being that 1-1 is replaced by 130-2. The molecular mass determined by mass spectrometry is 590.26 (theoretical value: 590.39). Compound 130 was synthesized using the same method as compound 1, except that 1-7 was replaced with 130-3. The other steps were the same. The molecular mass determined by mass spectrometry was 947.80 (theoretical value: 947.93).
[0031] Example 14: Synthesis of Compound 135 ; The synthesis methods of 135-2 and 32-3 are the same, except that 135-1 is used instead of 32-1. The molecular mass determined by mass spectrometry is 345.31 (theoretical value: 345.45). The synthesis methods of 135-4 and 1-5 are the same, except that 1-1 is replaced with 135-2. The other steps are the same. The molecular mass determined by mass spectrometry analysis is 703.63 (theoretical value: 703.77). The synthesis method of 135-6 is the same as that of 1-3. The difference is that 1-1 is replaced by 135-5. The molecular mass determined by mass spectrometry is 658.29 (theoretical value: 658.42). Compound 135 was synthesized using the same method as compound 1, except that 1-7 was replaced with 135-6 and 1-5 was replaced with 135-4. The other steps were the same. The molecular mass determined by mass spectrometry was 1152.15 (theoretical value: 1152.03).
[0032] Example 15: Synthesis of Compound 159 ; Compound 159 was synthesized using the same method as compound 1, except that 32-4 replaced 1-7 and 32-5 replaced 1-5. The other steps were the same. The molecular mass determined by mass spectrometry was 1075.98 (theoretical value: 1076.10).
[0033] Example 16: Synthesis of Compound 185 ; The synthesis methods of 185-2 and 1-3 are the same, except that 185-1 is used instead of 1-2. The molecular mass determined by mass spectrometry is 584.56 (theoretical value: 584.68). The synthesis method of 185-4 is the same as that of compound 1, except that 1-7 is replaced by 185-2. The other steps are the same. The molecular mass determined by mass spectrometry is 942.07 (theoretical value: 942.22). Compound 185 was synthesized using the same method as 21-3, except that 21-1 was replaced by 185-5 and 21-2 was replaced by 185-4. The molecular mass determined by mass spectrometry was 1072.85 (theoretical value: 1072.97).
[0034] Example 17: Synthesis of Compound 192 ; The synthesis methods of 192-1 and 1-3 are the same, except that 1-1 is replaced by 72-1. The molecular mass determined by mass spectrometry is 616.59 (theoretical value: 616.43). Compound 192 was synthesized using the same method as compound 1, except that 1-7 was replaced with 192-1. The other steps were the same. The molecular mass determined by mass spectrometry was 973.84 (theoretical value: 973.96).
[0035] Example 18: Synthesis of Compound 223 ; The synthesis methods for 223-4 and 1-5 are the same, except that 223-1 replaces 1-1 and 223-2 replaces 1-2. The other steps are the same. The molecular mass determined by mass spectrometry analysis is 701.66 (theoretical value: 701.79). The synthesis method of 223-5 is the same as that of 1-3, except that 1-2 is replaced by 223-2. The molecular mass determined by mass spectrometry is 654.29 (theoretical value: 654.39). Compound 223 was synthesized using the same method as compound 1, except that 1-7 was replaced with 223-5 and 1-5 was replaced with 223-4. The other steps were the same. The molecular mass determined by mass spectrometry was 1086.18 (theoretical value: 1086.05).
[0036] Example 19: Synthesis of Compound 228 ; The synthesis methods for 228-3 and 1-5 are the same, except that 1-1 is replaced with 228-1. The other steps are the same. The molecular mass determined by mass spectrometry analysis is 669.68 (theoretical value: 669.81). The synthesis method of 228-4 is the same as that of 1-3, except that 1-2 is replaced by 4-1. The molecular mass determined by mass spectrometry is 640.68 (theoretical value: 640.79). Compound 228 was synthesized using the same method as compound 4, except that 228-4 replaced 4-2 and 228-3 replaced 1-5. The other steps were the same. The molecular mass determined by mass spectrometry was 1003.89 (theoretical value: 1004.01).
[0037] Example 20: Synthesis of Compound 233 ; The synthesis method of 233-2 is the same as that of 1-5. The difference is that 1-3 is replaced by 233-1. The molecular mass determined by mass spectrometry is 360.17 (theoretical value: 360.34). Synthesis of 233-3: Under a nitrogen atmosphere, n-BuLi (1.6 M, 2.5 mL) was slowly added dropwise to a dry t-BuPh (50 mL) solution of 233-2 (1.44 g, 4.0 mmol), and the reaction was carried out at 0 °C for 2 h. Then, a t-BuPh (20 mL) solution of benzophenone (728 mg, 4.0 mmol) was slowly added dropwise, and the mixture was allowed to cool naturally to room temperature. The reaction was quenched with H₂O, and the organic solvent was removed by rotary evaporation. The crude product was purified by column chromatography and recrystallized from THF and MeOH to obtain the intermediate. HCl (3.7 mL) was slowly added dropwise to the intermediate CH3COOH (37.0 mL) solution. After stirring for 10 min under a nitrogen atmosphere, the mixture was rapidly vacuum filtered to obtain a filter cake. The cake was washed with MeOH and then recrystallized with THF and MeOH to obtain 233-3 (1.23 g, 69%). The molecular weight determined by mass spectrometry was 445.52 (theoretical value: 445.65). The synthesis method of 233-4 is the same as that of 1-3, except that 1-1 is replaced by 233-3. The molecular mass determined by mass spectrometry is 782.53 (theoretical value: 782.65). Compound 233 was synthesized using the same method as compound 1, except that 233-4 replaced 1-7 and 32-5 replaced 1-5. The other steps were the same. The molecular mass determined by mass spectrometry was 1196.17 (theoretical value: 1196.29).
[0038] Example 21: Synthesis of Compound 243 ; Synthesis of 243-3: Under a nitrogen atmosphere, 243-2 (1.6 M, 6.3 mL) was slowly added dropwise to a solution of 243-1 (2.92 g, 10.0 mmol) in 50 mL of dry xylene. The reaction was carried out at -78 °C for 2 h, then naturally warmed to room temperature and stirred overnight. The reaction was quenched with water, and the aqueous phase was washed three times with DCM. The organic phases were combined, evaporated to dryness, and the crude product was purified by column chromatography. Recrystallization with THF and MeOH yielded 243-3 (3.11 g, 78%). The mass spectrometry analysis determined the mass fraction to be 398.45 (theoretical value: 398.59). The synthesis method of 243-4 is the same as that of 1-3, except that 1-1 is replaced by 243-3. The molecular mass determined by mass spectrometry is 735.46 (theoretical value: 735.59). Compound 243 was synthesized using the same method as compound 1, except that 1-7 were replaced with 263-4. The other steps were the same. The molecular mass determined by mass spectrometry was 1093.00 (theoretical value: 1093.13).
[0039] Other compounds for which specific synthesis steps are not listed can be prepared using common knowledge in the art, in conjunction with the above examples.
[0040] Device Examples Based on the same inventive concept, embodiments of the present invention also provide an organic electroluminescent device. The following example uses an OLED organic light-emitting device as an illustration; however, it should be understood that the following detailed description is not intended to limit the invention, and those skilled in the art can extend and apply the following detailed description to other organic light-emitting devices.
[0041] In a specific embodiment, a hole injection layer is formed on the anode layer, a hole transport layer is formed on the hole injection layer, an electron injection layer is formed on the electron transport layer, a cathode layer is formed on the electron injection layer, and a light-emitting layer is located between the hole transport layer and the electron transport layer.
[0042] Glass or polymer materials can be used as the substrate beneath the anode layer. Furthermore, thin-film transistors (TFTs) can also be incorporated into the substrate used for displays.
[0043] The anode layer material can be selected from transparent conductive oxide materials such as indium tin oxide (ITO), indium zinc oxide (IZO), tin dioxide (SnO2), and zinc oxide (ZnO), and any combination thereof. The cathode layer material can be metals or alloys such as magnesium (Mg), silver (Ag), aluminum (Al), aluminum-lithium (Al-Li), calcium (Ca), magnesium-indium (Mg-In), and magnesium-silver (Mg-Ag), and any combination thereof.
[0044] The hole injection layer can be selected from metalloporphyrins, oligothiophenes, arylamines, hexanitrile hexaazabenzophenanthrene, quinacridones, perylene materials, etc., but is not limited to these.
[0045] The hole transport layer can be selected from materials such as diphenylamine compounds, fluorene compounds, carbazole compounds, and aromatic amine derivatives, but is not limited to these.
[0046] The luminescent layer material typically contains a guest material and a host material, wherein the guest material is at least one of the polycyclic boron nitrogen compounds represented by the general formula (1) of this invention.
[0047] The electron transport layer can be selected from materials such as quinolines, imidazoles, o-phenanthroline compounds, triazoles, metal chelates, azabenzene derivatives, diazanthracene derivatives, silicon-containing heterocyclic compounds, boron-containing heterocyclic compounds, cyano compounds, and benzimidazoles, but is not limited to these.
[0048] The electron injection layer material can be selected from Li, Ca, Sr, LiF, CsF, CaF2, BaO, Li2CO3, CaCO3, Li2C2O4, Cs2C2O4, CsAlF4, LiOx, Yb, Tb, cesium 8-hydroxyquinoline, tris(8-hydroxyquinoline)aluminum, etc., but is not limited to these.
[0049] The cathode material may be selected from Ag, Mg, Cu, Al, Pt, Pd, Au, Ni, Nd, Ir, Cr, Li, Ca, LiF / Ca, LiF / Al, Mo, Ti, including their compounds or mixtures thereof (e.g., a mixture of Ag and Mg), but is not limited thereto.
[0050] The organic functional layer of the aforementioned organic electroluminescent device can be deposited by vacuum deposition, spin coating, casting, etc. When using vacuum deposition, the conditions for vacuum deposition vary depending on the compound.
[0051] To evaluate the luminescence performance of the polycyclic boron-nitrogen compounds of the present invention in organic electroluminescent devices, this application also provides some representative examples of electroluminescent devices. However, it should be noted that the following detailed description is not intended to limit the invention, and those skilled in the art can extend the application of the following detailed description to other organic electroluminescent devices.
[0052] An electroluminescent device with the structure [ITO / HATCN (6nm) / TAPC (50nm) / EML (20nm) / TmPyPb (60nm) / LiF (1nm) / Al (100nm)]; Its preparation method includes the following steps: (1) Substrate treatment: Transparent ITO glass was used as the substrate for preparing electroluminescent devices. It was first ultrasonically treated with 5% ITO washing solution for 30 min, and then ultrasonically washed with distilled water (2 times), acetone (2 times), and isopropanol (2 times) in sequence. It was baked in a clean environment until the solvent was completely removed, cleaned with ultraviolet light and ozone, and bombarded with low-energy cation beam.
[0053] (2) The device is fabricated using a vacuum deposition equipment with a vacuum evaporation process. The glass substrate is placed in the vacuum chamber of the evaporation equipment. When the vacuum degree of the vacuum evaporation system reaches 5×10 -4 Vapor deposition begins when the pressure is below Pa, and various organic layers, LiF electron injection layers, and metal Al electrodes are sequentially deposited on ITO glass using a vacuum evaporation process.
[0054] HATCN is used as the hole injection layer, TAPC is used as the hole transport layer, EML represents the light-emitting layer, the light-emitting layer is based on 2,6-DCzPPy, and the polycyclic boron nitrogen compound prepared in this invention is used as the guest material (doping material) with a doping weight percentage of 10%. TmPyPb is used as the electron transport layer, and LIF is used as the electron injection layer.
[0055] Preparation of Examples 1-21: When forming the light-emitting layer, the corresponding compounds in Table 1 were used as guest materials, and the devices of the examples were prepared using the above preparation method.
[0056] Preparation of Comparative Examples 1-3: When forming the light-emitting layer, the corresponding compounds in Table 1 were used as guest materials, and comparative devices were prepared using the above preparation method.
[0057] The structures of the compounds used in the above preparation process are as follows: ; At 1 cd / m 2 The maximum external quantum efficiency (EQE) of the fabricated device was measured at a brightness of 1000 cd / m². 2 The efficiency roll-off (attenuation) percentage of the device was measured at a brightness of 50 mA / cm². 2 The time required for the brightness to decrease to 95% of the initial brightness at a given current density (device lifetime LT95) was measured. External quantum efficiency, efficiency roll-off, and lifetime are all relative values (based on Comparative Example 1). Detailed data are shown in Table 1. ; As can be seen from Table 1 above, compared with Comparative Examples 2 and 3, the series of compounds of the present invention have significantly enhanced the intramolecular charge transfer effect through the synergistic effect of the double BN donor-acceptor units to construct a long conjugated framework, effectively regulating the energy level structure of the molecule, achieving excellent bipolar carrier transport performance, and significantly improving the efficiency and lifespan of the device. Compared with Comparative Example 1, this invention, by adjusting the rigid conjugate framework and introducing an unsaturated five-membered ring derivative structure at the end as a light-emitting guest, exhibits the advantages of high-efficiency light emission and long lifetime under high-concentration doping.
[0058] The above embodiments only list the effect data of devices made from a portion of the structures. This is a representative sampling test. Based on the experimental data, the overall data is not significantly different and can represent the effects of other unlisted structures.
[0059] Those skilled in the art will readily recognize that many modifications and variations can be made to the invention without departing from its spirit and scope. Therefore, it is contemplated that the invention covers the modifications and variations provided within the scope of the appended claims and their equivalents.
[0060] The applicant declares that the organic electroluminescent material and organic electroluminescent device of the present invention are illustrated through the above embodiments, but the present invention is not limited to the above embodiments, that is, it does not mean that the present invention must rely on the above embodiments to be implemented. Those skilled in the art should understand that any improvements to the present invention, equivalent substitutions of the raw materials of the product of the present invention, addition of auxiliary components, selection of specific methods, etc., all fall within the protection scope and disclosure scope of the present invention.
Claims
1. A polycyclic diboron nitrogen compound containing indole, the structure of which is shown in any one of general formulas (1) to (3): ； in, Ring A is independently selected from C6-C 12 aryl or C5-C 12 The heteroaryl groups; rings B are each independently selected from C6-C6. 12 The aryl group; X1 is selected from O, S, Se, NR3, CR4R5; X2 is selected from single bond, O, S, Se, NR3, CR4R5; A singlet indicating whether something exists or not; R is independently selected from hydrogen, deuterium, cyano, trifluoromethyl, deuterated or undeuterated C1-C atoms. 10 Alkyl, substituted or unsubstituted C6-C 18 Arylsilyl, substituted or unsubstituted C6-C 18 Aryl, substituted or unsubstituted C5-C 18 Heteroaryl, substituted or unsubstituted diarylamine, where n is from 1 to the largest substitution site in the ring; R1 and R2 are each independently selected from hydrogen, deuterium, cyano, trifluoromethyl, deuterated or undeuterated C1-C atoms. 10 Alkyl, substituted or unsubstituted C6-C 12 Aryl or C5-C 12 Heteroaryl, substituted or unsubstituted diarylamine; R1 and R2 can be linked together to additionally form alicyclic or aromatic monocyclic or polycyclic compounds; R3 is independently selected from substituted or unsubstituted phenyl groups; R4 and R5 are independently selected from deuterated or undeuterated C1-C4 alkyl groups, substituted or unsubstituted phenyl groups; R4 and R5 can be linked together to additionally form alicyclic or aromatic monocyclic or polycyclic groups. When substitutions are present, the substituents are independently selected from deuterium, cyano, trifluoromethyl, deuterated or undeuterated methyl, deuterated or undeuterated isopropyl, deuterated or undeuterated tert-butyl, deuterated or undeuterated phenyl; the heteroatoms are N, O, S, and Se.
2. The indole-containing polycyclic diboron nitrogen compound according to claim 1, characterized in that, X1 is selected from O, S, and NR3.
3. The indole-containing polycyclic diboron nitrogen compound according to claim 1, characterized in that, X2 is selected from single bonds, O, S, and NR. 3。 4. The indole-containing polycyclic diboron nitrogen compound according to claim 1, characterized in that, Each of the R atoms is independently selected from hydrogen atoms, deuterium atoms, deuterated or undeuterated C1-C4 alkyl groups, substituted or unsubstituted C6-C groups. 12 Arylsilyl, substituted or unsubstituted C6-C 12 Aryl, substituted or unsubstituted C5-C 12 Heteroaryl, substituted or unsubstituted diarylamine.
5. The indole-containing polycyclic diboron nitrogen compound according to claim 1, characterized in that, R1 and R2 are each independently selected from hydrogen atoms, deuterium atoms, deuterated or undeuterated C1-C4 alkyl groups, substituted or unsubstituted C6-C atoms. 12 Aryl or C5-C 12 Mixed aromatic compounds.
6. The indole-containing polycyclic diboron nitrogen compound according to any one of claims 1-5, characterized in that, The specific structure of this compound is as follows: ； ； ； ； ； ； ； ； ； 。 7. An organic electroluminescent device, comprising an anode, a cathode, and an organic functional layer disposed between the anode and the cathode, the organic functional layer comprising a light-emitting layer, a hole injection layer, a hole transport layer, an electron transport layer, and an electron injection layer, characterized in that, The luminescent layer comprises at least one of the indole-containing polycyclic diboron nitrogen compounds according to any one of claims 1 to 6.
8. The organic electroluminescent device according to claim 7, wherein the light-emitting layer comprises a host material and a guest material, characterized in that, The guest material comprises at least one of the indole-containing polycyclic diboron nitrogen compounds according to any one of claims 1 to 6.
9. The organic electroluminescent device according to claim 7, characterized in that, This organic electroluminescent device is used to manufacture display devices, lighting sources, signal lights, and signs. The display devices include mobile phone displays, computer displays, television displays, smartwatch displays, smart car display panels, and VR or AR helmet displays.