Compound with meta-substituted cyano structure and organic electroluminescent device thereof

Abstract

The invention belongs to the technical field of organic electroluminescent materials, and particularly relates to a compound with a meta-substituted cyano structure and an organic electroluminescent device of the compound. Benzo five-membered heterocycle or five-membered heterocycle is introduced to a parent nucleus with the meta-substituted cyano structure to serve as a central parent nucleus; and the synergistic effect of multiple beneficial effects is realized on the molecular level. The compound is a sensitizer with good performance, has a smaller energy gap, a higher anti-intersystem crossing coefficient and a higher radiative transition radiation rate, and also has higher fluorescence quantum efficiency and a more suitable emission peak position; the organic light-emitting device prepared by using the compound as the sensitizer has lower turn-on voltage, higher current efficiency and longer service life, and the comprehensive performance of the device can be balanced.

Description

Technical Field

[0001] This invention belongs to the field of organic electroluminescent materials technology, and particularly relates to a compound with a meta-substituted cyano structure and its organic electroluminescent device. Background Technology

[0002] Organic light-emitting diodes (OLEDs) are the core of next-generation display and lighting technologies, and their device efficiency has always been a key research focus. During electroluminescence, electrons and holes recombine to generate excitons, with the statistical ratio of singlet to triplet excitons being approximately 1:3. Effectively utilizing the dominant 75% of triplet excitons is crucial to overcoming the efficiency bottleneck of OLEDs.

[0003] First-generation fluorescent OLED materials can only utilize 25% of singlet excitons for emission, limiting their theoretical upper limit of internal quantum efficiency to 25%. To fully utilize triplet excitons, researchers have developed second-generation phosphorescent OLED materials. Phosphorescent materials, by introducing heavy metal atoms such as iridium (Ir) and platinum (Pt), utilize their strong spin-orbit coupling effect to simultaneously capture singlet and triplet excitons and achieve radiative emission, thus enabling the device to achieve an internal quantum efficiency of 100%. However, phosphorescent materials, especially blue phosphorescent materials, generally suffer from poor stability and severe efficiency roll-off. Furthermore, their dependence on rare and precious metals leads to high costs and potential environmental burdens, limiting their large-scale application.

[0004] To balance high efficiency, high stability, and low cost, the academic community has proposed an advanced strategy called "sensitized luminescence." The core idea of ​​this strategy is to separate the functions of materials: one material acts as a "sensitizer," responsible for efficiently capturing and managing excitons, while another material acts as a "luminescent guest," responsible for achieving efficient and stable light output. In this system, the sensitizer, acting as an energy transfer station, is first excited and then transfers energy to the luminescent guest through efficient Förster resonance energy transfer mechanisms, ultimately resulting in luminescence by the guest material. This allows high-quality fluorescent materials that are insensitive to direct electrical excitation to be indirectly excited, thereby maximizing their performance.

[0005] The emergence of thermally activated delayed fluorescence (TADF) materials has provided a key solution for ideal sensitizers. As a purely organic semiconductor, TADF materials possess an extremely small singlet-triplet energy level difference due to their molecular design, allowing triplet excitons to be converted into luminescent singlet excitons through a reverse intersystem crossing process, theoretically achieving 100% exciton utilization. The "superfluorescent" system built upon TADF materials uses TADF as the sensitizer and traditional fluorescent materials with high photoluminescence quantum yield and narrow-spectrum emission as the luminescent terminal. This architecture cleverly combines the advantages of both: the TADF sensitizer ensures efficient utilization of all electrogenerated excitons, solving the efficiency bottleneck; while the final fluorescence emission provides excellent color purity and material stability, while avoiding dependence on noble metals.

[0006] Therefore, developing high-performance TADF sensitizers and optimizing their energy level matching and energy transfer efficiency with fluorescent guests has become a core research direction to promote the development of OLED technology towards high performance and low cost, which is of vital importance to realizing the next generation of high-performance display and lighting technologies. Summary of the Invention

[0007] To address the problems existing in the background art, the present invention provides a compound having a meta-substituted cyano structure, the structure of which is shown in general formula (I): ; L is selected from single bond, substituted or unsubstituted C6-C. 12 Aromatic rings, substituted or unsubstituted C3-C 12 Mixed fragrance ring; A and B are each independently selected from substituted or unsubstituted C6-C. 12 Aromatic ring or (I)-1, (I)-2, (I)-3, (I)-4, and at least one of A and B is selected from (I)-1, (I)-2, (I)-3, (I)-4: ; C is selected from (I)-5, (I)-6, and (I)-7, and D is selected from (I)-6 or (I)-7: ; X1 is independently selected from NR3, O, S, and Se; X2 is independently selected from N and CR5; and E is independently selected from R2-substituted C6-C. 12 Aromatic rings or C3-C6 heteroaromatic rings, X3~X 11 Each is independently selected from single bonds, CR6R7, O, S, and Se; R1 to R7 are each independently selected from hydrogen, deuterium, cyano, C1-C6 alkyl, substituted or unsubstituted C6-C6. 12Aryl or C3-C 12 heteroaryl groups; When substitution is present, the substituents are each independently selected from deuterium, cyano, C1-C6 alkyl, C6 ... 12 The aryl group and the heteroaryl group of C3-C6 are represented by *, where * indicates the linking site, and n is the number of substitution sites from 1 to the maximum number of substitution sites in the ring. The heteroatoms are selected from N, O, S, and Se.

[0008] As a preferred embodiment of the present invention, E is selected from an R2-substituted benzene ring.

[0009] As a preferred embodiment of the present invention, X3 is selected from single bonds and CR6R7.

[0010] As a preferred embodiment of the present invention, X4, X 11 It is a single key; one of X5 and X6 is a single key; one of X7 and X8 is a single key; X9 and X... 10 One of them is a single bond, and (I)-6 is selected from the following structures: ; (I)-7 is selected from the following structures: ; .

[0011] As a preferred embodiment of the present invention, one of A and B is selected from (I)-1, (I)-2, (I)-3, and (I)-4.

[0012] As a preferred embodiment of the present invention, A and B are each independently selected from (I)-1 or (I)-2.

[0013] As a preferred embodiment of the present invention, C is selected from (I)-5 or (I)-6.

[0014] As a preferred embodiment of the present invention, R1 to R5 are each independently selected from hydrogen, deuterium, cyano, methyl, phenyl, and pyridine, and R6 and R7 are the same as each other, selected from methyl, phenyl, or phenyl groups bonded together. When substitution is present, the substituents are each independently selected from deuterium, cyano, methyl, phenyl, and pyridyl.

[0015] As a preferred embodiment of the present invention, the compound having a meta-substituted cyano structure has the following specific structure: ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; .

[0016] Another object of the present invention is to provide an organic electroluminescent device having an anode, a cathode, and an organic layer, wherein the organic layer includes a light-emitting layer, and the light-emitting layer includes the above-described compound having a meta-substituted cyano structure.

[0017] The beneficial effects of this invention are as follows: The compounds with meta-substituted cyano structures provided by this invention achieve multiple beneficial synergistic effects at the molecular level by introducing a benzo5-membered heterocycle or a five-membered heterocycle as the central core. Firstly, they optimize carrier balance and exciton generation: the benzo5-membered heterocycle or five-membered heterocycle structure has excellent electron transport characteristics, which facilitates the efficient injection and transport of electrons to the light-emitting layer, thereby balancing the electron and hole concentrations in the device and promoting the efficient generation of excitons. Secondly, they promote the efficient utilization of triplet excitons: this molecular structure design effectively reduces the singlet-triplet bandgap (ΔE). ST This enhances the push-pull electron effect within the molecule, promoting not only short-range charge transfer but also significantly improving the spatial vibrational orbital coupling ability. This property greatly increases the reverse intersystem crossing rate (k... RISCThis invention enables the efficient conversion of triplet excitons into luminescent singlet excitons, improving luminescence efficiency and stability. The compounds exhibit higher radiative transition rates, allowing for more efficient conversion of triplet excitons into photons, thus achieving higher fluorescence quantum efficiency. Simultaneously, it effectively suppresses the annihilation process of triplet excitons, contributing to improved spectral stability. Finally, it enables applications in high-performance devices: the emission spectra of the compounds in this invention match the absorption spectra of commonly used doped materials more closely, ensuring that exciton energy can be more efficiently captured and utilized by the luminescent guest, ultimately resulting in higher green light luminescence efficiency and longer device lifetime in organic electroluminescent devices. Attached Figure Description

[0018] The accompanying drawings, which are included to provide a further understanding of the invention and form part of this invention, illustrate exemplary embodiments of the invention and are used to explain the invention, but do not constitute an undue limitation of the invention. In the drawings: Figure 1 The 1H NMR spectrum of Chemical 1 in this invention; Figure 2 This is a transient lifetime decay curve of chemical 1 in this invention. Detailed Implementation

[0019] The technical solution of the present invention will be clearly and completely described below with reference to synthetic embodiments and device embodiments. Obviously, the described embodiments are only a part of the embodiments of the present invention, and not all of them. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present invention.

[0020] Synthesis Examples

[0021] Example 1: Synthesis of Chemical 1

[0022] Synthesis of 1-2: Under a nitrogen atmosphere, 1-1 (6.9 g, 25.4 mmol) and tetrahydrofuran solution (120 mL) were added to a 1 L three-necked flask. After the reaction system was cooled to -60 °C, lithium diisopropylaminolithium (LDA) (29.2 mL, 58.4 mmol) was slowly added dropwise to the reaction system. After stirring for 2 hours, dimethylformamide (DMF) (5.9 mL, 76.2 mmol) was added to the reaction system, and stirring was continued for 30 minutes. Water was added, and the mixture was brought to room temperature. The mixture was extracted with ethyl acetate, and the extracted organic layer was washed with brine and dried with anhydrous Na2SO4. After drying, the solvent was removed by rotary evaporation under reduced pressure to obtain the crude product. The crude product was purified by silica gel column chromatography to obtain 1-2 (7.0 g, 84%). The molecular weight determined by mass spectrometry was 328.04 (theoretical value: 327.91). Synthesis of 1-4: Under nitrogen protection, 1-3 (3.0 g, 24 mmol), 1-2 (3.3 g, 10 mmol), and sodium cyanide (1.2 g, 24 mmol) were added sequentially to a 1 L three-necked flask and dissolved in 60 mL of N,N-dimethylformamide (DMF). The reaction was carried out in an oil bath at 100 °C for 6 hours. After the reaction was completed by TLC monitoring, the reaction system was cooled to room temperature, 80 mL of water was added, and the mixture was extracted with ethyl acetate. The organic phase was concentrated and then purified by column chromatography to obtain 1-4 (2.3 g, 43%). The molecular weight determined by mass spectrometry was 534.04 (theoretical value: 534.15). Synthesis of 1-5: Under a nitrogen atmosphere, 1-4 (7.1 g, 13.2 mmol), cuprous cyanide (CuCN) (5.9 g, 66 mmol), and N,N-dimethylformamide (DMF) (40 mL) were placed in a 100 mL three-necked flask, heated to 150 °C, and stirred at this temperature for 8 hours. After the reaction was complete, the mixture was cooled to room temperature, and 18 mL of ammonia was added to the reaction system. The organic layer was extracted with dichloromethane, washed with water and brine, collected, and dried over anhydrous magnesium sulfate. After drying, the solvent was removed under reduced pressure using a rotary evaporator. The crude product obtained after solvent removal under reduced pressure was purified by silica gel column chromatography to obtain 1-5 (4.6 g, 82%). The molecular weight determined by mass spectrometry was 426.52 (theoretical value: 426.38). Synthesis of 1-7: Under nitrogen atmosphere, 1-5 (4.3 g, 10 mmol), 1-6 (2.4 g, 10 mmol), cesium carbonate (8.2 g, 25 mmol), and N,N-dimethylformamide (50 mL) were added to a 250 mL two-necked flask. The reaction was carried out overnight at 120 °C under nitrogen protection. Heating was stopped, and after cooling to room temperature, 150 mL of water was added and stirred for 10 min. A large amount of white solid precipitated. The solid was filtered, and the filter cake was washed with ethanol for 2 h. After cooling, the solid was filtered again to obtain 1-7 (4.4 g, 68%). The molecular weight determined by mass spectrometry was 649.55 (theoretical value: 649.69). Synthesis of Chemical 1: Under a nitrogen atmosphere, 1-7 (6.5 g, 10 mmol), 1-8 (2.9 g, 10 mmol), cesium carbonate (8.2 g, 25 mmol), and N,N-dimethylformamide (50 mL) were added to a 250 mL two-necked flask. The reaction was carried out overnight at 120 °C under nitrogen protection. Heating was stopped, and after cooling to room temperature, 150 mL of water was added and stirred for 10 min. A large amount of white solid precipitated. The solid was filtered, and the filter cake was washed with ethanol for 2 h. After cooling, the solid was filtered again to obtain Chemical 1 (6.4 g, 70%). The molecular weight determined by mass spectrometry was 915.16 (theoretical value: 915.03).

[0023] Example 2: Synthesis of Chemical 39

[0024] Synthesis of 39-3: Under nitrogen atmosphere, 39-1 (2.0 g, 10 mmol) and 39-2 (3.0 g, 22 mmol) were dissolved in dimethyl sulfoxide (DMSO) (100 mL) in a 250 mL three-necked flask. Potassium carbonate (5.5 g, 40 mmol) was then added to the reaction mixture, and the mixture was heated and stirred at 100 °C for 4 hours. After cooling, the reaction mixture was poured into water, and the aqueous layer was extracted with ethyl acetate. The mixed organic phase was washed with water and brine, and then the organic phase was collected and dried over anhydrous sodium sulfate. After filtration, the organic phase was evaporated using a rotary evaporator to remove organic reagents, and recrystallized from the organic phase with methanol to give 39-3 (3.2 g, 73%), with a molecular weight determined by mass spectrometry of 433.67 (theoretical value: 433.55). Synthesis of 39-4: Under nitrogen atmosphere, 39-3 (10.8 g, 25 mmol), palladium trifluoroacetate (Pd(TFA)2) (0.8 g, 2.5 mmol), silver acetate (AgOAc) (16.7 g, 100 mmol), potassium carbonate (3.5 g, 25 mmol), and tertival acid (PivOH) (50 mL) were added to a 500 mL three-necked flask. The mixture was stirred at 130 °C for 24 hours. After the reaction was complete, the reaction mixture was cooled to room temperature, and dichloromethane and water were added for separation. The organic phase was collected, and the filtrate was concentrated using a rotary evaporator. The concentrated crude product was purified by column chromatography to obtain 39-4 (4.4 g, 41%). The molecular weight determined by mass spectrometry was 429.68 (theoretical value: 429.52). Synthesis of 39-5: Under nitrogen protection and at -78°C, a THF / hexane solution of LDA (10.5 mL, 2.0 M, 21 mmol) was slowly added to a THF solution of 1-1 (5.4 g, 20 mmol) (60 mL). After the addition was complete, the mixture was stirred at -78°C for 1 hour. Subsequently, trichlorosilane (3.3 g, 30 mmol) was added to the reaction mixture, and the mixture was slowly heated to room temperature and stirred for 12 hours. After the reaction was complete, the reaction solution was filtered through a diatomaceous earth filter and washed with dichloromethane. The filtrate was evaporated under reduced pressure, and the residue was purified by silica gel column chromatography (petroleum ether) to give 39-5 (5.2 g, 75%), with a molecular weight determined by mass spectrometry of 344.19 (theoretical value: 344.07). Synthesis of 39-6: 14.1 g (41 mmol) of 39-5 was placed in a 1 L three-necked flask, and anhydrous THF (400 mL) solution was added. Nitrogen gas was purged three times. At -78 °C, LDA (2.0 M, 49 mmol) was added dropwise to the reaction solution. After stirring for 1 hour at the same temperature, 21 g (82 mmol) of iodine in THF (200 mL) solution was added dropwise to the reaction system. The reaction mixture was stirred at -78 °C for another 1 hour and then gradually brought to room temperature. The reaction solution was quenched with HCl (3M, 100mL), and the mixture was stirred for 0.5h. The organic layer was separated, the aqueous layer was extracted with ethyl acetate, the organic phase was collected, and dried with anhydrous Na2SO4. After drying, the solvent was removed by rotary evaporation under reduced pressure to obtain the crude product. The crude product was purified by silica gel column chromatography to obtain 39-6 (16.0g, 83%). The molecular weight determined by mass spectrometry was 469.83 (theoretical value: 469.97). Synthesis of 39-8: 39-6 (17.9 g, 38 mmol), 39-7 (6.6 g, 41 mmol), tetrakis(triphenylphosphine)palladium (Pd(PPh3)4) (0.44 g, 0.38 mmol), and potassium carbonate (11 g, 76 mmol) were placed in a 1 L three-necked flask. The mixture was purged three times with nitrogen. Under a nitrogen atmosphere, toluene / ethanol / water = 400 mL / 100 mL / 200 mL was added. The mixture was heated to 60 °C and maintained at this temperature. The reaction was carried out for 12 hours. After the reaction system cooled to room temperature, the organic phase was collected by separation. The organic phase was washed with brine and the aqueous phase was extracted with ethyl acetate. The organic phases were combined and dried with anhydrous magnesium sulfate. After drying, the solvent was removed by rotary evaporation under reduced pressure to obtain the crude product. The crude product was purified by silica gel column chromatography to obtain 39-8 (15.4 g, 88%). The molecular weight determined by mass spectrometry was 460.33 (theoretical value: 460.19). Synthesis of 39-9: Under a nitrogen atmosphere, 39-8 (9.0 g, 19.5 mmol) and dichloromethane (100 mL) were added to a 1 L three-necked flask. Iodine monochloride (5.4 g, 33.2 mmol) was dissolved in dichloromethane (100 mL) and added dropwise to the reaction system at 0 °C. After the addition was complete, the mixture was stirred at 40 °C for 4 hours. After the reaction was complete, the mixture was allowed to return to room temperature, and a saturated sodium bisulfite aqueous solution (30 mL) was added to quench the reaction. The organic layer was extracted with dichloromethane, washed with water and brine, and the organic phase was collected, dried over magnesium sulfate, filtered, and concentrated using a rotary evaporator. The concentrated compound was purified by silica gel column chromatography to obtain 39-9 (7.5 g, 75%). The molecular weight determined by mass spectrometry was 514.04 (theoretical value: 513.9). The synthesis methods of 39-11 and 39-8 are the same, the difference being that 39-6 is replaced by 39-9 and 39-7 is replaced by 39-10. The molecular mass determined by mass spectrometry analysis is 464.23 (theoretical value: 464.1). The synthesis method of 39-12 is the same as that of 1-5. The difference is that 39-11 is used instead of 1-4. The molecular mass determined by mass spectrometry is 356.47 (theoretical value: 356.33). The synthesis methods of 39-14 and 17 are the same, the difference is that 39-12 replaces 1-5 and 39-13 replaces 1-6. The molecular mass determined by mass spectrometry analysis is 553.42 (theoretical value: 553.56). The synthesis method of Chemical 39 is the same as that of Chemical 1. The difference is that 39-14 replaces 1-7 and 39-4 replaces 1-8. The molecular mass determined by mass spectrometry is 963.32 (theoretical value: 963.07).

[0025] Example 3: Synthesis of Chemical 82

[0026] Synthesis of 82-2: 1-2 (7.9 g, 24 mmol), 82-1 (6.3 g, 50 mmol), and urea nitrate (0.9 g, 7 mmol) were placed together in a mortar under solvent-free conditions and ground at room temperature. Thin-layer chromatography (TCL) was used to monitor the mixture during the grinding process. After the reaction was complete, the crude product was poured into ice water and stirred for 30 minutes. The mixture was then filtered. The solid residue was recrystallized from ethanol to obtain 82-2 (10.7 g, 83%). The molecular weight determined by mass spectrometry was 538.36 (theoretical value: 538.22). The synthesis methods of 82-3 and 1-5 are the same, except that 1-4 is replaced by 82-2. The molecular mass determined by mass spectrometry is 430.32 (theoretical value: 430.45). Synthesis of Chemical 82: Under a nitrogen atmosphere, 82-3 (4.3 g, 10 mmol), 82-4 (7.7 g, 22 mmol), cesium carbonate (16.4 g, 50 mmol), and N,N-dimethylformamide (100 mL) were added to a 250 mL two-necked flask. The reaction was carried out overnight at 120 °C under nitrogen protection. Heating was stopped, and after cooling to room temperature, 300 mL of water was added and stirred for 10 min. A large amount of white solid precipitated. The solid was filtered, and the filter cake was washed with ethanol for 2 h. After cooling, the solid was filtered again to obtain Chemical 82 (8.2 g, 75%). The molecular weight determined by mass spectrometry was 1089.18 (theoretical value: 1089.34).

[0027] Example 4: Synthesis of Chemical 85

[0028] The synthesis methods of 85-1 and 39-6 are the same, the difference being that 1-1 is used instead of 39-5. The molecular mass determined by mass spectrometry is 397.89 (theoretical value: 397.78). The synthesis methods of 85-3 and 39-8 are the same, the difference being that 39-6 is replaced by 85-1 and 39-7 is replaced by 85-2. The molecular mass determined by mass spectrometry analysis is 418.94 (theoretical value: 419.08). The synthesis methods of 85-4 and 39-6 are the same, except that 39-5 is replaced by 85-3. The molecular mass determined by mass spectrometry is 545.11 (theoretical value: 544.98). The synthesis methods of 85-6 and 39-8 are the same, the difference being that 39-6 is replaced by 85-4 and 39-7 is replaced by 85-5. The molecular mass determined by mass spectrometry is 502.05 (theoretical value: 502.19). The synthesis methods of 85-7 and 1-5 are the same, the difference being that 1-4 is replaced by 85-6. The molecular mass determined by mass spectrometry is 394.55 (theoretical value: 394.42). The synthesis methods of 85-8 and 1-7 are the same, except that 1-5 is replaced by 85-7. The molecular mass determined by mass spectrometry analysis is 617.58 (theoretical value: 617.72). The synthesis method of Chemical 85 is the same as that of Chemical 1. The difference is that 1-7 is replaced by 85-8 and 1-8 is replaced by 85-9. The molecular mass determined by mass spectrometry is 947.30 (theoretical value: 947.17).

[0029] Example 5: Synthesis of Chemical 137

[0030] Synthesis of 137-1: Under a nitrogen atmosphere, 1-1 (6.9 g, 25.4 mmol) and tetrahydrofuran solution (60 mL) were added to a 1 L three-necked flask. After the reaction system was cooled to -60 °C, lithium diisopropylaminolithium (LDA) (14.6 mL, 29.2 mmol) was slowly added dropwise to the reaction system. After stirring for 2 hours, dimethylformamide (DMF) (3.0 mL, 38.1 mmol) was added to the reaction system, and stirring was continued for 30 minutes. Water was added, and the mixture was brought to room temperature. The mixture was extracted with ethyl acetate, and the extracted organic layer was washed with brine and dried with anhydrous Na2SO4. After drying, the solvent was removed by rotary evaporation under reduced pressure to obtain the crude product. The crude product was purified by silica gel column chromatography to obtain 137-1 (5.8 g, 76%). The molecular weight determined by mass spectrometry was 299.73 (theoretical value: 299.90). Synthesis of 137-3: Under nitrogen protection, 137-2 (1.3 g, 12 mmol), 137-1 (4.3 g, 14.4 mmol), and sodium cyanide (0.6 g, 12 mmol) were added sequentially to a 1 L three-necked flask and dissolved in 60 mL of N,N-dimethylformamide (DMF). The reaction was carried out in an oil bath at 100 °C for 6 hours. After the reaction was completed by TLC monitoring, the reaction system was cooled to room temperature, and 80 mL of water was added for extraction with ethyl acetate. The organic phase was concentrated and then purified by column chromatography to obtain 137-3 (2.0 g, 43%). The molecular weight determined by mass spectrometry was 388.86 (theoretical value: 388.99). The synthesis methods for 137-4 and 39-6 are the same, except that 39-5 is replaced by 137-3. The molecular weight determined by mass spectrometry is 515.00 (theoretical value: 514.89). The synthesis methods for 137-6 and 39-8 are the same, except that 39-6 is replaced by 137-4. The molecular weight determined by mass spectrometry is 470.26 (theoretical value: 470.12). The synthesis methods for 137-7 and 1-5 are the same, except that 137-6 is replaced by 1... -4, molecular mass determined by mass spectrometry: 585.47 (theoretical value: 585.65); 137-9 is synthesized in the same way as 1-7, except that 1-5 is replaced by 137-7 and 1-6 is replaced by 137-8. Molecular mass determined by mass spectrometry: 362.21 (theoretical value: 362.35); Chemical 137 is synthesized in the same way as Chemical 1, except that 1-7 is replaced by 137-9 and 1-8 is replaced by 137-10. Molecular mass determined by mass spectrometry: 822.82 (theoretical value: 822.94).

[0031] Example 6: Synthesis of Chemical 151

[0032] Synthesis of 151-3: Under nitrogen atmosphere, 151-1 (2.0 g, 10 mmol) and 151-2 (1.9 g, 10 mmol) were dissolved in dimethyl sulfoxide (DMSO) (50 mL) in a 250 mL three-necked flask. Potassium carbonate (2.8 g, 20 mmol) was then added to the reaction mixture, and the mixture was heated and stirred at 100 °C for 4 hours. After cooling, the reaction mixture was poured into water, and the aqueous layer was extracted with ethyl acetate. The mixed organic matter was washed with water and brine, and the organic phase was collected and dried over anhydrous sodium sulfate. After filtration, the organic phase was subjected to rotary evaporation to remove organic reagents, and recrystallized from the organic phase with methanol to give 151-3 (2.4 g, 65%), with a molecular weight determined by mass spectrometry of 369.33 (theoretical value: 369.46). The synthesis methods for 151-5 and 151-3 are the same, except that 151-3 replaces 151-1 and 151-4 replaces 151-2. The molecular weight determined by mass spectrometry is 459.50 (theoretical value: 459.63). The synthesis methods for 151-6 and 39-4 are the same, except that 151-5 replaces 39-3. The molecular weight determined by mass spectrometry is 455.73 (theoretical value: 455.59). Synthesis of 151-8: 151-7 (3.4 g, 24 mmol), 82-1 (3.1 g, 25 mmol), and urea nitrate (0.4 g, 3.5 mmol) were placed together in a mortar under solvent-free conditions and ground and mixed at room temperature, with thin-layer chromatography (TCL) monitoring the process. After the reaction was complete, the crude product was poured into ice water and stirred for 30 minutes. The mixture was then filtered, and the solid residue was recrystallized from ethanol to obtain 151-8 (5.1 g, 86%). The molecular weight determined by mass spectrometry was 247.11 (theoretical value: 247.26). Synthesis of 151-9: Under a nitrogen atmosphere, 151-8 (5.3 g, 21.5 mmol), copper bromide (6 g, 42 mmol), palladium acetate (0.25 g, 1.1 mmol), and N,N-dimethylacetamide (DMA) (50 mL) were added to a dried 1 L round-bottom flask. The reaction mixture was placed in an oil bath at 120 °C and stirred for 12 hours. After the reaction was complete, the reaction mixture was cooled to room temperature, and ethyl acetate (50 mL) was mixed with the reaction system. The organic layer was washed with saturated sodium bicarbonate solution and dried with anhydrous sodium sulfate. After drying, the organic solvent was removed by rotary evaporation under reduced pressure. The crude product was purified by silica gel column chromatography to obtain 151-9 (3.7 g, 43%), with a molecular weight determined by mass spectrometry of 404.91 (theoretical value: 405.05). The synthesis methods for 151-10 and 39-6 are the same, except that 39-5 is replaced by 151-9. The molecular weight determined by mass spectrometry is 530.81 (theoretical value: 530.95). The synthesis methods for 151-11 and 39-8 are the same, except that 39-6 is replaced by 151-10 and 39-7 is replaced by 39-10. The molecular weight determined by mass spectrometry is 481.28 (theoretical value: 481.15). The synthesis methods for 151-12 and 1-5 are the same, except that... 151-11 replaces 1-4, and the molecular mass determined by mass spectrometry is 373.24 (theoretical value: 373.38); 151-14 is synthesized in the same way as 1-7, except that 1-5 is replaced by 151-12 and 1-6 is replaced by 151-13, and the molecular mass determined by mass spectrometry is 596.85 (theoretical value: 596.68); Chemical 151 is synthesized in the same way as Chemical 1, except that 1-7 is replaced by 151-14 and 1-8 is replaced by 151-6, and the molecular mass determined by mass spectrometry is 1032.09 (theoretical value: 1032.27).

[0033] Example 7: Synthesis of Chemical 206

[0034] Synthesis of 206-2: Under a nitrogen atmosphere, 2,2,6,6-tetramethylpiperidine lithium (LiTMP) (26.1 mL, 153 mmol) and THF (236 mL) were added to a 1 L three-necked flask and cooled to 0 °C using an ice bath. At 0 °C, n-butyllithium (1.6 M hexane solution) (96 mL, 153 mmol) was added dropwise to the reaction solution. After the addition was complete, the mixture was stirred at 0 °C for 30 minutes. The reaction system was then cooled to -78 °C. Triisopropyl borate (B(OiPr)3) (33.3 g, 177 mmol) and 206-1 (29.2 g, 118 mmol) were added sequentially. After all the addition was complete, the reaction system was slowly heated from -78 °C to room temperature. After the reaction was complete, 100 mL of 10% hydrochloric acid was added dropwise. Subsequently, liquid-liquid extraction was performed, the organic layer was collected, and washed with petroleum ether to obtain 206-2 (21.6 g, 63%). The molecular weight determined by mass spectrometry was 291.05 (theoretical value: 290.91). Synthesis of 206-3: Under a nitrogen atmosphere, 206-2 (15.1 g, 52 mmol), N-chlorosuccinimide (NCS) (7.0 g, 52 mmol), cuprous chloride (I) (5.2 g, 52 mmol), and acetonitrile (174 mL) were added to a 1 L three-necked flask. The reaction mixture was heated to 60 °C and stirred for 6 hours. After the reaction was complete, 150 mL of dichloromethane and 100 mL of water were added to the reaction mixture. The organic phase was collected by separation and dried over anhydrous sodium sulfate. The organic solvent was removed under reduced pressure using a rotary evaporator. The crude product was purified by silica gel column chromatography to obtain 206-3 (10.4 g, 71%). The molecular weight determined by mass spectrometry was 281.39 (theoretical value: 281.53). Synthesis of 206-4: Under a nitrogen atmosphere, 206-1 (12.4 g, 50 mmol), copper oxide (I) (0.1 g, 0.66 mmol), ammonia (100 mL, 30%), and NMP (N-methylpyrrolidone) (100 mL) were added to a 500 mL three-necked flask. The reaction system was slowly heated to 80 °C and stirred at this temperature for 12 hours. After the reaction was complete, the reaction system was brought to room temperature, and 300 mL of deionized water was added. The mixture was extracted with dichloromethane, and the organic phase was collected, washed with brine, and dried with anhydrous sodium sulfate. The dried organic phase was concentrated using a rotary evaporator. The crude product obtained after concentration was purified by silica gel column chromatography to obtain 206-4 (7.3 g, 80%). The molecular weight determined by mass spectrometry was 183.05 (theoretical value: 183.21). Synthesis of 206-5: Under a nitrogen atmosphere, 206-4 (8.2 g, 45 mmol), 206-3 (12.7 g, 45 mmol), tris(dibenzylacetone)dipalladium(0) (0.8 g, 0.9 mmol), tri-tert-butylphosphine (P(t-Bu)3) (1.0 g, 1.8 mmol), sodium tert-butoxide (6.5 g, 68 mmol), and 400 mL of toluene were added to a 1 L three-necked flask. The reaction system was heated to 100 °C and stirred at this temperature for 8 hours. After the reaction was complete, the reaction mixture was cooled to room temperature. Add 300 mL of deionized water to the reaction system, collect the organic phase by separation, dry with anhydrous sodium sulfate, remove organic reagents under reduced pressure using a rotary evaporator, and purify the crude product by silica gel column chromatography to obtain 206-5 (11.6 g, 67%). The molecular weight determined by mass spectrometry is 383.98 (theoretical value: 383.83). Synthesis of 206-6: Under a nitrogen atmosphere, 206-5 (7.9 g, 20.7 mmol), 1,3-bis(26-diisopropylphenyl)imidazolium chloride (IPrHCl) (0.36 g, 0.82 mmol), palladium(II) acetate (0.093 g, 0.41 mmol), potassium carbonate (5.8 g, 42 mmol), and 60 mL of N,N-dimethylacetamide (DMAc) were added to a 500 mL three-necked flask. The reaction system was heated to 160 °C and stirred for 10 hours. After the reaction was complete, it was cooled to room temperature. The solid precipitated in the reaction system was filtered, and the filter cake was washed three times with acetone. The filter cake was collected and dried in a vacuum oven to obtain 206-6 (5.2 g, 67%). The molecular weight determined by mass spectrometry was 374.51 (theoretical value: 374.37). The synthesis methods for 206-7 and 151-8 are the same, except that 137-1 is used instead of 151-7. The molecular weight determined by mass spectrometry is 405.18 (theoretical value: 405.05). The synthesis methods for 206-8 and 39-6 are the same, except that 206-7 is used instead of 39-5. The molecular weight determined by mass spectrometry is 530.78 (theoretical value: 530.95). The synthesis methods for 206-9 and 39-8 are the same, except that 206-8 is used instead of 39-6, and 39-10 is used instead of 39-5. 9-7, molecular mass determined by mass spectrometry: 480.96 (theoretical value: 481.15); 206-10 is synthesized in the same way as 1-5, except that 1-4 is replaced by 206-9, molecular mass determined by mass spectrometry: 373.24 (theoretical value: 373.38); Chemical 206 is synthesized in the same way as Chemical 82, except that 82-3 is replaced by 206-10 and 82-4 is replaced by 206-6, molecular mass determined by mass spectrometry: 1028.94 (theoretical value: 1028.11).

[0035] Example 8: Synthesis of Chemical 267

[0036] The synthesis methods for 267-2 and 206-4 are the same, except that 206-1 is replaced by 267-1. The molecular mass determined by mass spectrometry is 213.16 (theoretical value: 213.3). The synthesis methods for 267-5 and 29-8 are the same, except that 39-6 is replaced by 267-3 and 39-7 is replaced by 267-4. The molecular mass determined by mass spectrometry is 261.98 (theoretical value: 262.15). Synthesis of 267-6: Under a nitrogen atmosphere, 267-5 (1.8 g, 7 mmol), 4 M HCl (17.5 mL, 70 mmol), and 10 mL acetonitrile were added to a 250 mL three-necked flask, and the mixture was stirred thoroughly. The reaction system was cooled to 0 °C, and at this temperature, an aqueous solution of NaNO2 (7.7 mL, 7.7 mmol, 1 M) was slowly added dropwise, and stirring was continued for 45 minutes. Subsequently, an aqueous solution of KI (8.8 mL, 17.5 mmol, 2 M) was added dropwise to the reaction system at 0 °C, and stirring was continued at 0 °C for 5 minutes. The reaction was then continued to be stirred at room temperature for 2 hours until complete. The mixture was extracted with ethyl acetate, dried over anhydrous sodium sulfate, and the organic phase was removed by rotary evaporation under reduced pressure. The crude product was purified by silica gel column chromatography to obtain 267-6 (2.0 g, 75%), with a molecular weight determined by mass spectrometry of 373.17 (theoretical value: 373.03). Synthesis of 267-7: Under a nitrogen atmosphere, 267-6 (1.9 g, 5 mmol) was placed in a 250 mL three-necked flask and dissolved using DCM (20 mL, 0.25 M). Then, m-CPBA (2.03 g, 10 mmol) was added in multiple portions. After the m-CPBA was completely dissolved, the reaction solution was cooled to 0 °C, and TfOH (1.3 mL, 15 mmol) was added dropwise at this temperature. After the addition was complete, the reaction system was brought back to room temperature and stirred for 2 hours. After the reaction was complete, dichloromethane was removed under reduced pressure using a rotary evaporator. Diethyl ether was then added to the reaction residue, and the mixture was stirred at room temperature for 30 minutes. The residue was then filtered to obtain a filter cake, which was repeatedly washed with diethyl ether. The filter cake was collected and dried in a vacuum oven to obtain 267-7 (1.7 g, 64%). The molecular weight determined by mass spectrometry was 521.22 (theoretical value: 521.09). Synthesis of 267-8: Under a nitrogen atmosphere, 267-7 (5.2 g, 10 mmol), KOt-Bu (4.5 g, 40 mmol), Se (2.4 g, 30 mmol), and 200 mL of DMSO were added to a 500 mL three-necked flask. The resulting mixture was stirred at 100 °C for 2 hours. After the reaction system cooled to room temperature, 15 mL of water was added. The reaction mixture was extracted with ethyl acetate, and the organic layers were combined and dried over anhydrous sodium sulfate. The organic phase was purified by column chromatography after removing the solvent under reduced pressure using a rotary evaporator, yielding 267-8 (2.5 g, 78%) with a molecular weight determined by mass spectrometry of 324.20 (theoretical value: 324.09). The synthesis methods for 267-9 and 39-6 are the same, except that 39-5 is replaced by 267-8. The molecular mass determined by mass spectrometry is 450.13 (theoretical value: 449.99). Synthesis of 267-10: Under a nitrogen atmosphere, 267-9 (20.2 g, 45 mmol), 267-2 (9.6 g, 45 mmol), tris(dibenzylacetone)dipalladium(0) (0.8 g, 0.9 mmol), 2-biscyclohexylphosphine-2',4',6'-triisopropylbiphenyl(x-phos) (0.4 g, 0.9 mmol), sodium tert-butoxide (6.5 g, 68 mmol), and 400 mL of toluene were added to a 1 L three-necked flask. The reaction mixture was heated to 100 °C and stirred for 8 hours. After the reaction was complete, the reaction mixture was cooled to room temperature. Add 300 mL of deionized water to the reaction system, collect the organic phase by separation, dry with anhydrous sodium sulfate, remove organic reagents under reduced pressure using a rotary evaporator, and purify the crude product by silica gel column chromatography to obtain 267-10 (15.2 g, 63%), with a molecular weight determined by mass spectrometry of 535.54 (theoretical value: 535.37). Synthesized 267-11 and 206-6 are synthesized using the same method, except that 206-5 is replaced by 267-10. The molecular mass determined by mass spectrometry is 454.60 (theoretical value: 454.46). Synthesized 267-12 and 137-1 are synthesized using the same method, except that 1-1 is replaced by 39-5. The molecular mass determined by mass spectrometry is 372.26 (theoretical value: 372.08). Synthesized 267-14 and 137-3 are synthesized using the same method, except that 137-1 is replaced by 267-12 and 137-2 is replaced by 267-13. The molecular mass determined by mass spectrometry is 489.09 (theoretical value: 489.23). Synthesis of 267-15: Under a nitrogen atmosphere, 264-14 (9.5 g, 19.5 mmol) and dichloromethane (100 mL) were added to a 1 L three-necked flask. Iodine monochloride (5.4 g, 33.2 mmol) was dissolved in dichloromethane (100 mL) and added dropwise to the reaction system at 0 °C. After the addition was complete, the mixture was stirred at 40 °C for 4 hours. After the reaction was complete, the mixture was allowed to return to room temperature, and a saturated sodium bisulfite aqueous solution (30 mL) was added to quench the reaction. The organic layer was extracted with dichloromethane, washed with water and brine, and the organic phase was collected, dried over magnesium sulfate, filtered, and concentrated using a rotary evaporator. The concentrated compound was purified by silica gel column chromatography to obtain 267-15 (7.9 g, 75%). The molecular weight determined by mass spectrometry was 542.75 (theoretical value: 542.94). The synthesis methods for 267-16 and 39-8 are the same, except that 39-6 is replaced by 267-15 and 39-7 by 39-10. The molecular weight determined by mass spectrometry is 493.27 (theoretical value: 493.15). The synthesis methods for 267-17 and 1-5 are the same, except that 1-4 is replaced by 267-16. The molecular weight determined by mass spectrometry is 385.49 (theoretical value: 385.37). The synthesis methods for -19 and 1-7 are the same, except that 1-5 is replaced by 267-17 and 1-6 is replaced by 267-18. The molecular mass determined by mass spectrometry is 714.95 (theoretical value: 714.82). The synthesis methods for 267 and 1 are the same, except that 1-7 is replaced by 267-19 and 1-8 is replaced by 267-11. The molecular mass determined by mass spectrometry is 1149.11 (theoretical value: 1149.27).

[0037] Example 9: Synthesis of Chemical 271

[0038] The synthesis methods for 271-2 and 206-4 are the same, except that 206-1 is replaced by 271-1. Mass spectrometry analysis determined the molecular mass to be 275.50 (theoretical value: 275.37). The synthesis methods for 271-3 and 206-5 are the same, except that 206-4 is replaced by 271-2. Mass spectrometry analysis determined the molecular mass to be 476.13 (theoretical value: 475.99). The synthesis methods for 271-4 and 206-6 are the same, except that 271-2 is used instead of 206-1. 271-3 replaced 206-5, and the molecular mass determined by mass spectrometry was 439.67 (theoretical value: 439.53). 271-6 and 39-8 were synthesized using the same method, except that 85-1 replaced 39-6 and 271-5 replaced 39-7. The molecular mass determined by mass spectrometry was 463.97 (theoretical value: 464.1). 271-7 and 39-6 were synthesized using the same method, except that 271-6 replaced 39-5. The molecular mass determined by mass spectrometry was... The molecular mass of 271-8 is 589.88 (theoretical value: 590.0). The synthesis methods for 271-8 and 39-8 are the same, except that 39-6 is replaced by 271-7 and 39-7 by 39-10. The molecular mass determined by mass spectrometry is 540.06 (theoretical value: 540.20). The synthesis methods for 271-9 and 1-5 are the same, except that 1-4 is replaced by 271-8. The molecular mass determined by mass spectrometry is 432.29 (theoretical value: 4). 32.43); The synthesis method of 271-11 is the same as that of 1-7, except that 1-5 is replaced by 271-9 and 1-6 is replaced by 271-10. The molecular mass determined by mass spectrometry is 655.59 (theoretical value: 655.73); The synthesis method of chemical 271 is the same as that of chemical 1, except that 1-7 is replaced by 271-11 and 1-8 is replaced by 271-4. The molecular mass determined by mass spectrometry is 1074.41 (theoretical value: 1075.26).

[0039] Example 10: Synthesis of Chemical 343

[0040] Synthesized as 343-1 and 39-8, the difference lies in replacing 39-6 with 85-1 and 39-7 with 39-10. The molecular weight determined by mass spectrometry is 348.11 (theoretical value: 347.98). Synthesized as 343-2 and 39-6, the difference lies in replacing 39-5 with 343-1. The molecular weight determined by mass spectrometry is 474.02 (theoretical value: 473.88). Synthesized as 343-4 and 39-8, the difference lies in replacing 39-6 with 343-2 and 39-7 with 343-3. The molecular weight determined by mass spectrometry is 495.04 (theoretical value: 495.18). Synthesized as 343-5 and 1-5, the difference lies in replacing 1-4 with 343-3. The molecular weight determined by mass spectrometry is 387.27 (theoretical value: 387.41). Synthesis of 343-6: Under a nitrogen atmosphere, 343-5 (4.8 g, 12.5 mmol), 70 mL of dioxane, and 40 mL of water were added to a 1 L three-necked flask. Then, 1.5 mL of ammonia (30 wt%) was added to the flask. The reaction system was heated to 80 °C and stirred for 10 hours at this temperature. After the reaction was complete, the reaction solvent was cooled to room temperature. Extraction was performed with ethyl acetate, and the organic phase was collected and dried with anhydrous sodium sulfate. The solvent was removed from the organic phase using a rotary evaporator under reduced pressure, and the residue was purified by silica gel column chromatography to obtain a solid, yielding 343-6 (4.7 g, 98%). The molecular weight determined by mass spectrometry was 384.31 (theoretical value: 384.43). Synthesis of 343-7: Under a nitrogen atmosphere, 343-6 (19.6 g, 51 mmol), iodine (26 g, 102 mmol), and 125 mL of acetonitrile were added to a 500 mL three-necked flask. Then, tert-butyl nitrite (t-BuONO) (10 g, 102 mmol) was added to the reaction system, and the mixture was stirred at 25 °C for 8 hours. After the reaction was complete, 50 mL of saturated sodium bisulfite aqueous solution was added to the reaction solution. The reaction system was separated, and the organic phase was collected and dried using anhydrous sodium sulfate. The organic phase was subjected to reduced pressure evaporation using a rotary evaporator to remove the solvent from the resulting solution, and then purified by silica gel column chromatography to obtain 343-7 (15.9 g, 63%). The molecular weight determined by mass spectrometry was 495.17 (theoretical value: 495.31). The synthesis methods of 343-9 and 396-8 are the same, except that 39-6 is replaced by 343-7 and 39-7 is replaced by 343-8. The molecular mass determined by mass spectrometry is 610.56 (theoretical value: 610.71). The synthesis methods of chemical 343 and chemical 1 are the same, except that 1-7 is replaced by 343-9 and 1-8 is replaced by 343-10. The molecular mass determined by mass spectrometry is 996.33 (theoretical value: 996.20).

[0041] The above synthetic examples illustrate representative synthetic routes. Unless otherwise specified, all reagents and instruments used are commercially available conventional products. Some reaction compounds were purchased from a supplier (Zhengzhou Alpha Chemical Co., Ltd.), while some compounds that could not be directly purchased were prepared from commercially available raw materials through simple reactions. All percentages refer to mass percentages. The principles, procedures, routine post-processing, silica gel column chromatography, recrystallization purification, and other techniques of this method are well-known to those skilled in the art and can be fully implemented to obtain the target product.

[0042] In addition, it should be noted that other compounds in this application can be obtained by referring to the synthetic routes of the synthetic examples listed above, so they will not be listed one by one here.

[0043] Device Examples To evaluate the luminescence performance of the compounds described in this invention in organic electroluminescent devices, a series of OLED devices based on multilayer organic thin film structures were designed and constructed, and the specific fabrication process is shown below:

[0044] Preparation of Example 1: The glass plate coated with the ITO transparent conductive layer was ultrasonically treated in a cleaning agent, rinsed in deionized water, ultrasonically degreased in a mixed solvent of acetone and ethanol, baked in a clean environment until all moisture was removed, cleaned with ultraviolet light and ozone, and bombarded with a low-energy cation beam. The treated ITO transparent conductive layer was placed in a vacuum evaporation chamber. After the system reached a high vacuum, a hole injection layer (HIL) with a thickness of 10 nm was first deposited. This layer used a co-evaporation combination of HT and HI-1 (mass ratio 97:3, w / w), with the two materials placed in different evaporation sources. Precise ratio control was achieved by adjusting the evaporation rate. This doping system aims to improve the energy level matching between the anode and the organic layer and reduce the hole injection barrier. A 15 nm thick HT-1 layer is deposited on top of the hole injection layer as a hole transport layer (HTL). The main function of this layer is to efficiently transport holes and suppress electron back injection, maintaining a good charge balance in the device. Subsequently, a 20 nm thick HT-2 layer is deposited as an electron blocking layer (EBL) to restrict electron penetration to the hole transport layer, thereby effectively improving the exciton binding ability and recombination efficiency in the light-emitting region. A 30nm thick light-emitting layer (EML) was deposited on the electron blocking layer using a multi-source co-evaporation process. The main material was HOST, the sensitizer was MH, and the dopant was GD-1. The materials were placed in independent evaporation sources, and the co-doped composite light-emitting film was formed by controlling the evaporation rate ratio to 49:50:1 (w / w / w). A 5nm thick HB-1 layer is deposited on the light-emitting layer as a hole blocking layer (HBL) to block holes from escaping into the electron region and enhance the electron injection interface. A 30 nm thick electron transport layer (ETL) was deposited on the hole blocking layer using an ET-1 and LiQ doping system (mass ratio 50:50, w / w). This combination helps to improve the electron transport rate and interface injection efficiency. Depositing 1 nm of Yb on the electron transport layer as an electron injection layer (EIL) helps to form an interfacial dipole and improve the injection efficiency of electrons from the Al cathode to the electron transport layer. A Mg:Ag electrode layer with a thickness of 13 nm is deposited on top of the electron injection layer, wherein the mass ratio of Mg to Ag is 1:9. This layer serves as the cathode layer. A CP-1 layer with a thickness of 65 nm was vacuum-deposited on the cathode as a light extraction layer (CPL). The entire organic layer and cathode evaporation process is completed in a continuous vacuum to avoid interface oxidation or contamination, with the deposition rate set to 0.1 nm / s.

[0045] In the glove box, the vapor-deposited device is coated with UV adhesive using a coating equipment. The coated cover plate is then moved to the lamination section, where the vapor-deposited substrate is placed on top of the cover plate. Finally, the substrate and cover plate are laminated using a bonding equipment and cured with UV adhesive.

[0046] Preparation of Examples 2-30: When forming the light-emitting layer (EML), the corresponding compounds in Tables 2-1 and 2-2 were used to replace Compound 1 in Example 1, and the organic electroluminescent device was prepared using the same method as in Example 1.

[0047] Preparation of Comparative Examples 1-11: Except that when forming the light-emitting layer (EML), the corresponding compound in Table 3 was used to replace Compound 1 in Example 1, the organic electroluminescent device was prepared using the same method as in Example 1.

[0048] The structures of the compounds used in the device are as follows: .

[0049] Evaluation of compounds: The emission peak positions, photoluminescence quantum yield (PLQY), and antisystem crossing coefficients (k) of the compounds in Tables 1-1 and 1-2 were analyzed. RISC ) and radiative transition rate coefficient (k r ), singlet-triplet bandgap (ΔE) ST The PLQY test: Dissolve the sample in nitrogen-saturated toluene and prepare 10... -5 The mol / L solution was analyzed using a Hamamatsu PLQY spectrometer; the emission peak positions were determined using a fluorescence spectrometer; ΔE ST Phosphorescence and fluorescence at 77K were obtained using a HITACHI F-7000 spectrometer; k RISC and k r The results were obtained through testing and calculation using FLS1000, as shown in Tables 1-1 and 1-2 below: ; .

[0050] Device evaluation: The voltage was increased at a rate of 0.1V per second, and the brightness of the device embodiment and the comparative example was measured when they reached lcd / m². 2 The voltage at which it is turned on is 10 mA / cm. 2 The driving voltage and current efficiency of the device embodiments and comparative examples were determined at a current density of 35 mA / cm². The driving voltage and current efficiency were measured using an IVL (current-voltage-luminance) testing system (Suzhou Fushida Scientific Instruments Co., Ltd.). 2 The time required for the brightness to decrease to 95% of the initial brightness at a given current density (LT95) was measured. The lifetime testing system was the OLED lifetime testing system from Suzhou Fosstar Scientific Instruments Co., Ltd.; at 10 cd / m 2 The wavelength of the maximum emission peak, the full width at half maximum (FWHM), and the corresponding CIE color coordinates were obtained, and the results are shown in Tables 2-1, 2-2, and 3 below: ; ; .

[0051] The data in Tables 1-3 show that the series of compounds provided by this invention are high-performance sensitizers with a smaller band gap (ΔE). ST <0.01eV), and a higher anti-system crossing coefficient (k RISC ) and radiative transition rate (k r It also has high fluorescence quantum efficiency (PLQY) and more suitable emission peak position, which makes organic electroluminescent devices prepared using it as a sensitizer have low turn-on voltage, high current efficiency and long lifespan, thus balancing the overall performance of the device.

[0052] 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.

[0053] Those skilled in the art will readily recognize that many modifications and variations can be made to this invention without departing from its spirit and scope. Therefore, it is contemplated that this invention covers the modifications and variations provided within the scope of the appended claims and their equivalents.

[0054] 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 compound having a meta-substituted cyano structure, characterized in that, Its structure is shown in general formula (I): ； L is selected from single bond, substituted or unsubstituted C6-C. 12 Aromatic rings, substituted or unsubstituted C3-C 12 heterocyclic aromatic rings; A and B are each independently selected from substituted or unsubstituted C6-C. 12 Aromatic ring or (I)-1, (I)-2, (I)-3, (I)-4, and at least one of A and B is selected from (I)-1, (I)-2, (I)-3, (I)-4: ； C is selected from (I)-5, (I)-6, and (I)-7, and D is selected from (I)-6 or (I)-7: ； X1 is independently selected from NR3, O, S, and Se; X2 is independently selected from N and CR5; and E is independently selected from R2-substituted C6-C. 12 Aromatic rings or C3-C6 heteroaromatic rings, X3~X 11 Each is independently selected from single bonds, CR6R7, O, S, and Se; R1 to R7 are each independently selected from hydrogen, deuterium, cyano, C1-C6 alkyl, substituted or unsubstituted C6-C6. 12 Aryl or C3-C 12 heteroaryl groups; When substitution is present, the substituents are each independently selected from deuterium, cyano, C1-C6 alkyl, C6 ... 12 The aryl group and the heteroaryl group of C3-C6 are represented by *, where * indicates the linking site, and n is the number of substitution sites from 1 to the maximum number of substitution sites in the ring. The heteroatoms are selected from N, O, S, and Se.

2. The compound having a meta-substituted cyano structure according to claim 1, characterized in that, E is selected from a benzene ring substituted with R2.

3. The compound having a meta-substituted cyano structure according to claim 1, characterized in that, X3 is selected from single bond, CR6R7.

4. The compound having a meta-substituted cyano structure according to claim 1, characterized in that, X4, X 11 It is a single key; one of X5 and X6 is a single key; one of X7 and X8 is a single key; X9 and X... 10 One of them is a single bond, and (I)-6 is selected from the following structures: ； (I)-7 is selected from the following structures: ； 。 5. The compound having a meta-substituted cyano structure according to claim 1, characterized in that, One of A and B is selected from (I)-1, (I)-2, (I)-3, (I)-4.

6. The compound having a meta-substituted cyano structure according to claim 1, characterized in that, A and B are each independently selected from (I)-1 or (I)-2.

7. The compound having a meta-substituted cyano structure according to claim 1, characterized in that, C is selected from (I)-5 or (I)-6.

8. The compound having a meta-substituted cyano structure according to claim 1, characterized in that, R1 to R5 are each independently selected from hydrogen, deuterium, cyano, methyl, phenyl, and pyridine; R6 and R7 are the same and are selected from methyl, phenyl, or phenyl groups bonded together. When substitution is present, the substituents are each independently selected from deuterium, cyano, methyl, phenyl, and pyridyl.

9. The compound having a meta-substituted cyano structure according to any one of claims 1-8, characterized in that, The specific structure of this compound is as follows: ； ； ； ； ； ； ； ； ； ； ； ； ； ； ； ； ； ； ； ； ； ； 。 10. An organic electroluminescent device, comprising an anode, a cathode, and an organic layer, wherein the organic layer includes a light-emitting layer, characterized in that, The luminescent layer comprises any of the compounds with a meta-substituted cyano structure as described in claims 1-9.

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