A diboron polycyclic compound for organic electroluminescent devices

Abstract

The present invention discloses a diboron polycyclic compound for an organic electroluminescent device, belonging to the technical field of organic electroluminescent materials. The diboron polycyclic compound is directly bonded to N, O, S, and Se with a spiro derivative as the central B atom, and has high singlet and triplet energy, suitable HOMO and LUMO energy levels, and a small singlet-triplet energy difference. It is applied to an organic electroluminescent device as a luminescent material to improve the luminous efficiency of the device and improve the color purity of the device. After the diboron polycyclic compound of the present invention is applied to an OLED as a luminescent material, the relative value of the external quantum efficiency of the light-emitting device is 105.6% to 126.9%, and the half-peak width is 22 to 29nm. Compared with an OLED using BD01 as a luminescent material, the luminous efficiency is significantly improved, the emission spectrum half-peak width is narrower, and the color purity is higher. The present invention provides a MR-TADF material for improving the color purity of a blue light device.

Description

Technical Field

[0001] The invention belongs to the technical field of organic electroluminescent materials and relates to a diboron polycyclic compound used for an organic electroluminescent device. Background Art

[0002] Organic electroluminescent devices (OLEDs) are devices with organic materials as active light-emitting layers under the action of an electric field. They have the advantages of high brightness, fast response, wide viewing angle, simple process, and flexibility. The principle of light emission is to use ITO glass transparent electrodes and metal electrodes as the anode and cathode of the device respectively. Under a certain voltage drive, electrons and holes are injected from the cathode and anode into the electron transport layer and hole transport layer respectively, and then migrate to the light-emitting layer respectively. After meeting, excitons are formed to excite light-emitting molecules, and the light-emitting molecules emit visible light after radiation. With the iterative development of display technology, in order to meet high-quality display effects, the display standard (BT.2020) has extremely high requirements for the color purity of blue light devices, and the blue light CIEy=0.046. Blue shifting the emission spectrum can usually improve the color purity, but short-wave materials have wider band gaps and higher energy, and it is difficult to find a matching host material to achieve high efficiency. If a smaller CIEy value is achieved, the emission spectrum half-peak width of the material is required to be narrow enough under the premise that the light-emitting position is more suitable, and conventional fluorescent materials are difficult to meet the requirements.

[0003] In 2016, Professor HATAKEYAMA's team proposed the multi-resonance thermally delayed fluorescence (MR-TADF) material, which can effectively solve the color purity problem. MR-TADF materials have a unique configuration, which can make holes and electrons interact in the material molecules to achieve a resonance effect, reduce Stokes shift, narrow the spectrum, and improve color purity. At the same time, MR-TADF materials have the characteristics of thermally active delay, which can simultaneously utilize singlet and triplet energy. In theory, 100% internal quantum efficiency can be obtained to achieve high efficiency. However, the conditions for realizing thermally active delayed fluorescence blue light materials with multiple resonance effects are very harsh. It is necessary to ensure a wide band gap and meet the requirement that the energy level difference between the singlet and triplet states is small enough, and at the same time, the resonance effect must be achieved. How to construct a new compound to obtain MR-TADF materials is a hot spot and difficulty in the industry. Therefore, providing a MR-TADF material is of great significance to solving the color purity problem of blue light devices. Summary of the invention

[0004] In order to solve the above technical problems, the present invention provides a diboron polycyclic compound for an organic electroluminescent device. The diboron polycyclic compound is used as a luminescent material in an organic electroluminescent device to improve the color purity of the device and achieve high efficiency.

[0005] To achieve the technical purpose of the present invention, on the one hand, the present invention provides a diboron polycyclic compound having a structure as shown in formula (I),

[0006] ;

[0007] Y1 in the formula (I) is selected from a single bond, O, S, Se, NR1, CR2R3;

[0008] Y2 and Y3 in the formula (I) are independently selected from one of O, S, Se and NR4;

[0009] X1 and X2 in the formula (I) are independently selected from one of NR5, O, S, Se, and CR6R7;

[0010] Ar1 to Ar6 in the formula (I) are independently selected from a hydrogen atom, a deuterium atom, a C1-C5 alkyl group, a substituted or unsubstituted amine group, a substituted or unsubstituted C6-C30 aryl group, or a substituted or unsubstituted C6-C30 heteroaryl group.

[0011] Furthermore, in the diboron polycyclic compound provided by the present invention, R1 in NR1 is a substituted or unsubstituted phenyl or biphenyl group; R2 and R3 in CR2R3 are independently selected from one of methyl and phenyl groups.

[0012] Furthermore, in the diboron polycyclic compound provided by the present invention, R4 in NR4 is a substituted or unsubstituted phenyl group, R5 in NR5 is a substituted or unsubstituted phenyl group, and R6 and R7 in CR6R7 are independently selected from methyl or phenyl groups.

[0013] Furthermore, in the diboron polycyclic compound provided by the present invention, R4 in NR4 and R5 in NR5 are connected to N by a single bond or bonded to an adjacent benzene ring to form a ring. Ar1 to Ar6 can all bond to an adjacent benzene ring to form a ring. All hydrogen atoms in the diboron polycyclic compound can be arbitrarily deuterated.

[0014] Furthermore, the diboron polycyclic compound provided by the present invention has the structures shown in A1 to A6,

[0015]

[0016] .

[0017] Furthermore, in the diboron polycyclic compound provided by the present invention, A1 to A6 have the following structures:

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[0063] .

[0064] On the other hand, the present invention claims protection for the use of the above-mentioned diboron polycyclic compound in an organic electroluminescent device, wherein the diboron polycyclic compound is used as a light-emitting layer material in the organic electroluminescent device.

[0065] Furthermore, the present invention simulates and calculates the physicochemical properties of diboron polycyclic compounds and finds that diboron polycyclic compounds have more suitable HOMO / LUMO and higher triplet energy, and have a smaller singlet-triplet energy difference than the comparative material BD01, are more prone to intergap crossing inversion, and increase the intergap crossing inversion rate. As a multi-resonance blue light luminescent material, it can effectively improve the luminous efficiency and color purity of the device.

[0066] On the other hand, the present invention claims protection for an organic electroluminescent device comprising a light-emitting layer, wherein the material of the light-emitting layer comprises the above-mentioned diboron polycyclic compound.

[0067] Furthermore, after the prepared diboron polycyclic compound is applied as a light-emitting layer material to an organic electroluminescent device, the light-emitting device has excellent performance, and its external quantum efficiency relative value is 105.6%~126.9%, which is 5.6%~26.9% higher than that of the existing material BD01, and the half-peak width is 22~29nm. Compared with the existing material BD01 applied to OLED, after the diboron polycyclic compound of the present invention is applied as a light-emitting material to OLED, the luminous efficiency of the light-emitting device is significantly improved, the half-peak width of the emission spectrum is narrower, and the color purity is higher. It has great application value in the application of OLED and has good industrialization prospects.

[0068] Furthermore, the present invention seeks to protect a display component comprising the above-mentioned organic electroluminescent device.

[0069] Compared with the prior art, the technical solution provided by the present invention has at least the following beneficial effects or advantages:

[0070] (1) The structure of the diboron polycyclic compound prepared by the present invention, which has a spiro derivative as the central B atom and is directly bonded to N, O, S, and Se, is sufficiently twisted, has high singlet and triplet energies, suitable HOMO and LUMO energy levels, and a small singlet-triplet energy difference (△st). The present invention simulates and calculates the physicochemical properties of the diboron polycyclic compound and finds that the diboron polycyclic compound has a more suitable HOMO / LUMO and a higher triplet energy. Compared with the comparative material BD01, it has a smaller singlet-triplet energy difference, is more likely to undergo inter-gap crossing inversion, and improves the inter-gap crossing inversion rate. As a multi-resonance blue light emitting material, it can effectively improve the luminous efficiency and color purity of the device.

[0071] (2) The diboron polycyclic compound prepared by the present invention ensures that the compound has strong rigidity while making the compound have strong multiple resonance thermal activation delayed fluorescence (MR-TADF) effect. When used as a light-emitting layer material in an organic electroluminescent device, the emission spectrum can be narrowed, and the luminous efficiency and color purity of the light-emitting device can be improved. The diboron polycyclic compound of the present invention. After the diboron polycyclic compound prepared by the present invention is applied as a light-emitting layer material to an organic electroluminescent device, the light-emitting device has excellent performance, and its external quantum efficiency relative value is 105.6%~126.9%, which is 5.6%~26.9% higher than that of the existing material BD01, and the half-peak width is 22~29nm. Compared with the existing material BD01 applied to OLED, after the diboron polycyclic compound of the present invention is applied as a light-emitting material to OLED, the luminous efficiency of the light-emitting device is significantly improved, the half-peak width of the emission spectrum is narrower, and the color purity is higher. It has great application value in the application of OLED and has good industrialization prospects. BRIEF DESCRIPTION OF THE DRAWINGS

[0072] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings in the following description are only some embodiments of the present invention.

[0073] Figure 1 Schematic diagram of the structure of an organic electroluminescent device, wherein 1 is a substrate, 2 is an anode layer, 3 is a hole injection layer, 4 is a hole transport layer, 5 is an electron blocking layer, 6 is a light-emitting layer, 7 is a hole blocking layer, 8 is an electron transport layer, 9 is an electron injection layer, and 10 is a cathode layer. DETAILED DESCRIPTION

[0074] The technical scheme of the present invention is described below in conjunction with the embodiments, but the present invention is not limited to the following embodiments. The experimental methods and detection methods described in each embodiment are conventional methods unless otherwise specified; the reagents and materials described are all commercially available unless otherwise specified.

[0075] Example 1

[0076] This example provides the synthesis of compound 9 (Y1 is a single bond, Y2 and Y3 are both NR4, R4 is a phenyl group substituted by a C4 alkyl group, and R4 is bonded to an adjacent benzene ring to form a ring, X1 and X2 are both O, Ar1, Ar2, Ar5, and Ar6 are all hydrogen atoms, and Ar3 and Ar4 are all C4 alkyl groups). The synthesis route is shown below, and specifically comprises the following steps:

[0077] ;

[0078] S1: Under nitrogen protection, raw material 1 (50.10 g, 295.4 mmol), raw material 2 (95.47 g, 295.4 mmol), potassium carbonate (61.12 g, 443.1 mmol), toluene (300 mL), ethanol (100 mL), water (100 mL) were added in sequence to a three-necked flask equipped with a condenser, and then Pd(OAc)2 (0.33 g, 1.5 mmol) and X-Phos (1.43 g, 3.0 mmol) were added, and heated to 72°C for 6 h. The mixture was cooled to room temperature, washed with water until neutral, dried with MgSO4, filtered and concentrated, passed through a silica gel column, and recrystallized to obtain intermediate 9-1 (100.50 g, yield 92%).

[0079] S2: Under nitrogen protection, add intermediate 9-1 (100.50 g, 270.5 mmol), raw material 3 (47.37 g, 122.9 mmol), potassium carbonate (68.09 g, 470.9 mmol) and DMF (800 mL) to a three-necked flask equipped with a condenser, and heat under reflux for 10 h. After the reaction is completed, cool to room temperature, pour into water to form a white precipitate, filter, wash the precipitate with water and ethanol in turn, pass through a silica gel column, and recrystallize to obtain intermediate 9-2 (20.10 g, yield 15%).

[0080] S3: Under nitrogen protection, add intermediate 9-2 (20.10 g, 19.0 mmol) and o-dichlorobenzene (100 mL) to a three-necked flask equipped with a condenser, then slowly add boron tribromide (57.13 g, 228.5 mmol) dropwise, and heat to 150°C~160°C for 8 hours. After the reaction, cool the system to room temperature. Filter, add water, and a white precipitate is generated, which is filtered. The filter cake is washed with water and ethanol in turn, and finally passed through a silica gel column and recrystallized to obtain compound 9 (8.94 g, yield 44%). The characterization results of compound 9 are: HRMS: Measured value: 1071.5516 [M+H] + ; Exact mass: 1071.5227. C 65 H 58 O4B2 (%) calculated value: C, 86.35%; H, 6.02%; N, 2.62%; found value: C, 86.23%; H, 5.94%; N, 2.51%.

[0081] Example 2

[0082] This example provides the synthesis of compound 23 (Y1 is O, Y2 and Y3 are both NR4, R4 is an unsubstituted phenyl group, X1 and X2 are both Se, Ar1, Ar3, Ar4, Ar6 are all hydrogen atoms, and Ar2 and Ar5 are all C4 alkyl groups). The synthesis route is shown below, and specifically comprises the following steps:

[0083] ;

[0084] S1: Under nitrogen protection, raw material 4 (60.20 g, 158.7 mmol), raw material 5 (28.94 g, 72.1 mmol), potassium carbonate (32.85 g, 238.1 mmol) and DMF (800 mL) were added to a three-necked flask equipped with a condenser, and heated under reflux for 6 h. After the reaction was completed, it was cooled to room temperature and poured into water to form a white precipitate, which was filtered. The precipitate was washed with water and ethanol in turn, and finally passed through a silica gel column and recrystallized to obtain intermediate 23-1 (20.50 g, yield 26%).

[0085] S2: Under nitrogen protection, add intermediate 23-1 (20.50 g, 18.8 mmol) and o-dichlorobenzene (100 mL) to a three-necked flask equipped with a condenser, then slowly add boron tribromide (47.13 g, 188.2 mmol) dropwise, and heat to 160°C~170°C for 8 hours. After the reaction, cool the system to room temperature. Filter, add water, and a white precipitate is generated, which is filtered. The filter cake is washed with water and ethanol in turn, and finally passed through a silica gel column and recrystallized to obtain compound 23 (9.31 g, yield 45%). The characterization results of compound 23 are: HRMS: Measured value: 1107.2652 [M+H] + ; Exact mass: 1107.2669. C 65 H 58 O4B2 (%) calculated value: C, 75.02%; H, 4.74%; N, 2.54%; found value: C, 74.90%; H, 4.63%; N, 2.41%.

[0086] Example 3

[0087] This example provides the synthesis of compound 52 (Y1 is NR1, R1 is a deuterated phenyl group, Y2 and Y3 are both NR4, R4 is a phenyl group substituted by a C4 alkyl group, and R4 is bonded to an adjacent benzene ring to form a ring, X1 and X2 are both NR5, R5 is an unsubstituted phenyl group, Ar1, Ar2, Ar5, and Ar6 are all hydrogen atoms, and Ar3 and Ar4 are all C4 alkyl groups). The synthesis route is shown below, and specifically comprises the following steps:

[0088]

[0089]

[0090] S1: Under nitrogen protection, raw material 6 (50.00 g, 201.5 mmol), raw material 2 (65.13 g, 201.5 mmol), potassium carbonate (41.72 g, 302.2 mmol), toluene (300 mL), ethanol (100 mL) and water (100 mL) were added to a three-necked flask equipped with a condenser in sequence, and then Pd2(dba)3 (0.93 g, 1.0 mmol) and X-Phos (0.96 g, 2.0 mmol) were added, and heated to 72°C for 6 h. The mixture was cooled to room temperature, washed with water until neutral, dried with MgSO4, filtered and concentrated, passed through a silica gel column, and recrystallized to obtain intermediate 52-1 (60.20 g, yield 67%).

[0091] S2: Under nitrogen protection, add intermediate 52-1 (60.20 g, 134.8 mmol), raw material 7 (34.32 g, 61.3 mmol), sodium tert-butoxide potassium carbonate (17.67 g, 183.9 mmol) and DMF (600 mL) to a three-necked flask equipped with a condenser, then add Pd2(dba)3 (0.13 g, 0.14 mmol) and X-Phos (0.14 g, 0.28 mmol), heat to 130 ° C and react for 6 h. After the reaction is completed, cool to room temperature, pour into water to form a white precipitate, and filter. Wash the precipitate with water and ethanol in turn, pass through a silica gel column, and recrystallize to obtain intermediate 52-2 (25.10 g, yield 32%).

[0092] S3: Under nitrogen protection, add intermediate 52-2 (25.10 g, 19.4 mmol) and o-dichlorobenzene (110 mL) to a three-necked flask equipped with a condenser, then slowly add boron tribromide (48.55 g, 194.2 mmol) dropwise, and heat to 170°C~180°C for 8 hours. After the reaction, cool the system to room temperature. Filter, add a large amount of water, and a white precipitate is generated, which is filtered. The filter cake is washed with water and ethanol in turn, and finally passed through a silica gel column and recrystallized to obtain compound 52 (12.68 g, yield 50%). The characterization results of compound 52 are: HRMS: Measured value: 1308.2978 [M+H] + ; Exact mass: 1308.2994. C 65 H 58 O4B2 (%) calculated value: C, 87.22%; H, 5.78%; N, 5.35%; measured value: C, 87.11%; H, 5.64%; N, 5.28%.

[0093] Example 4

[0094] This example provides the synthesis of compound 61 (Y1 is CR2R3, R2 and R3 are both methyl groups, Y2 and Y3 are both NR4, R4 is an unsubstituted phenyl group, and R4 is bonded to an adjacent benzene ring to form a ring, X1 and X2 are both O, Ar1, Ar3, Ar4, and Ar6 are all hydrogen atoms, and Ar2 and Ar5 are all C4 alkyl groups). The synthesis route is as follows:

[0095]

[0096]

[0097] The synthesis method of compound 61 refers to the synthesis of compound 9, and raw material 2 is replaced by raw material 8 to prepare compound 61 (10.38 g, yield 48%). The characterization results of compound 61 are as follows: LC-MS: measured value: 1001.4438 [M+H] + ; Exact mass: 1001.4444. C 73 H 60 O3B2N2 (%) calculated value: C, 86.41%; H, 5.44%; N, 2.80%; measured value: C, 86.32%; H, 5.35%; N, 2.75%.

[0098] Example 5

[0099] This example provides the synthesis of compound 94 (Y1 is a single bond, Y2 and Y3 are both O, X1 and X2 are both O, Ar1 and Ar6 are both hydrogen atoms, and Ar2, Ar3, Ar4, and Ar5 are all C4 alkyl groups). The synthesis route is as follows:

[0100]

[0101]

[0102] The synthesis method of compound 94 refers to the synthesis of compound 9, except that raw material 1 is replaced by raw material 10 in S1, and raw material 2 is replaced by raw material 11. S2 is the same as S2 in Example 1.

[0103] S3: Under nitrogen protection, add intermediate 94-2 (55.30 g, 70.1 mmol) and dichloromethane (500 mL) to a three-necked flask equipped with a condenser, cool to 0°C~5°C, and then slowly add boron tribromide (35.10 g, 140.2 mmol). After the reaction is completed, pour the system into a large amount of ice water and filter. The filter cake is washed with water and ethanol in turn, and the solid is dried to obtain intermediate 94-3 (50.38 g, yield 95%).

[0104] S4 was the same as S3 in Example 1 to prepare compound 94 (9.87 g, yield 38%). The characterization results of compound 94 were as follows: HRMS: measured value: 925.4586 [M+H] + ; Exact mass: 925.4594. C 79 H 60 D5B2N3Se2 (%) calculated value: C, 84.42%; H, 6.32%; found value: C, 84.31%; H, 6.20%.

[0105] Example 6

[0106] This example provides the synthesis of compound 154 (Y1 is NR1, R1 is phenyl, Y2 and Y3 are both O, X1 and X2 are both NR5, R5 is a phenyl substituted with two methyl groups, Ar1 and Ar6 are both hydrogen atoms, and Ar2, Ar3, Ar4, and Ar5 are all C4 alkyl groups). The synthesis route is as follows:

[0107]

[0108] The synthesis method of compound 154 refers to the synthesis of compound 52, replacing intermediate 52-1 with raw material 12, and raw material 7 with raw material 13 to prepare compound 154 (10.62 g, yield 52%). The characterization results of compound 154 are as follows: HRMS: measured value: 1222.6572 [M+H] + ; Exact mass: 1222.6588. C 60 H 48 O2B2Se2 (%) calculated value: C, 85.49%; H, 6.68%; N, 3.44%; measured value: C, 85.36%; H, 6.56%; N, 3.38%.

[0109] Example 7

[0110] This example provides the synthesis of compound 164 (Y1 is a single bond, R1 is a phenyl group, Y2 and Y3 are both O, X1 and X2 are both NR5, R5 is a phenyl group substituted with two methyl groups and a C4 alkyl group, Ar1 and Ar6 are both hydrogen atoms, and Ar2, Ar3, Ar4, and Ar5 are all C4 alkyl groups). The synthesis route is as follows:

[0111]

[0112]

[0113] The synthesis method of compound 164 refers to the synthesis of compound 154, and raw material 12 is replaced by raw material 14, and raw material 13 is replaced by raw material 15 to prepare compound 164 (10.48 g, yield 46%). The characterization results of compound 164 are as follows: HRMS: measured value: 1091.57 [M+H] + ; Exact mass: 1091.54. C 214 H 192 O 10 B2Br2 (%) calculated value: C, 85.98%; H, 7.46%; N, 2.25%; found value: C, 85.84%; H, 7.37%; N, 2.16%.

[0114] Example 8

[0115] This example provides the synthesis of compound 182 (Y1 is a single bond, R1 is a phenyl group, Y2 and Y3 are both O, X1 and X2 are both NR5, R5 is a phenyl group substituted with two methyl groups and a C4 alkyl group, Ar1 and Ar6 are both hydrogen atoms, and Ar2, Ar3, Ar4, and Ar5 are all C4 alkyl groups). The synthesis route is as follows:

[0116]

[0117]

[0118] The synthesis method of compound 182 refers to the synthesis of compound 52, and raw material 6 is replaced by raw material 16, raw material 2 is replaced by raw material 17, and raw material 7 is replaced by raw material 5 to prepare compound 182 (11.50 g, yield 48%). The characterization results of compound 182 are as follows: HRMS: measured value: 1087.5165 [M+H] + ; Exact mass: 1087.5176. C 94 H 86 O2B2N2 (%) calculated value: C, 85.08%; H, 5.93%; N, 2.58%; measured value: C, 85.01%; H, 5.84%; N, 2.49%.

[0119] Example 9

[0120] This example simulates and calculates the physicochemical properties of diboron polycyclic compounds.

[0121] The S1, T1 energy levels and HOMO, LUMO simulation calculations were performed on Compound 1, Compound 9, Compound 11, Compound 12, Compound 23, Compound 25, Compound 27, Compound 29, Compound 35, Compound 40, Compound 52, Compound 59, Compound 61, Compound 66, Compound 72, Compound 78, Compound 85, Compound 88, Compound 90, Compound 94, Compound 127, Compound 154, Compound 164, Compound 182 and comparative material BD01. HOMO, LUMO, S1, T1 are the data obtained by simulation calculation, and the calculation method adopts B3LYP hybrid functional, basis set 6-31g (d, P), and the calculation results are shown in Table 1.

[0122] Table 1 Simulation results of the physicochemical properties of diboron polycyclic compounds

[0123]

[0124] As can be seen from Table 1, the diboron polycyclic compound prepared by the present invention has a more suitable HOMO / LUMO and a higher triplet energy. Compared with the comparative material BD01, it has a smaller singlet-triplet energy difference, is more likely to undergo inter-gap crossing inversion, and increases the inter-gap crossing inversion rate. As a multi-resonance blue light emitting material, it can effectively improve the luminous efficiency and color purity of the device.

[0125] Example 10

[0126] This embodiment provides the use of a diboron polycyclic compound as a light-emitting material in an organic electroluminescent device.

[0127] The structure of organic electroluminescent devices is as follows Figure 1 As shown, it includes a substrate 1, an anode layer 2, a hole injection layer 3, a hole transport layer 4, an electron blocking layer 5, a light emitting layer 6, a hole blocking layer 7, an electron transport layer 8, an electron injection layer 9 and a cathode layer 10 which are stacked in sequence.

[0128] Among them, the material of the anode layer 2 is indium tin oxide (ITO) with a high work function; the material of the hole injection layer 3 is HT1 doped with HI-1, the mass ratio of HT1 to HI-1 is 97:3, and the thickness is 10nm; the material of the hole transport layer 4 is HT1, with a thickness of 60nm; the material of the electron blocking layer 5 is EB1, with a thickness of 15nm; the light-emitting layer 6 uses BH1 as the main material and BD01 or a diboron polycyclic compound as the light-emitting material, with a doping mass ratio of 5% and a thickness of 30nm; the material of the hole blocking layer 7 is HB, with a thickness of 10nm; the electron transport layer 8 is composed of ET-1 doped with Liq, with a doping concentration of 50% and a thickness of 30nm; the material of the electron injection layer 9 is Liq, with a thickness of 2nm; the material of the cathode layer is Al, with a thickness of 100nm.

[0129] The material structure used in each functional layer of the device is as follows:

[0130]

[0131] The preparation of an organic electroluminescent device comprises the following steps:

[0132] 1) Clean the ITO anode on the transparent glass or plastic substrate, ultrasonically clean it with deionized water, acetone, and ethanol for 20 minutes each, and then perform plasma treatment for 5 minutes in an oxygen atmosphere; 2) Vacuum evaporation is used to deposit a hole injection layer on the ITO anode layer; 3) Vacuum evaporation is used to deposit a hole transport layer on the hole injection layer; 4) Vacuum evaporation is used to deposit an electron blocking layer on the hole transport layer HT1; 5) Vacuum evaporation is used to co-evaporate the light-emitting layer on the electron blocking layer, using BH1 as the main material and BD01 as the light-emitting material, with a doping mass ratio of 5% and a thickness of 30nm; 6) Vacuum evaporation is used to deposit a hole blocking layer on the light-emitting layer; 7) Vacuum evaporation is used to deposit an electron transport material layer on the hole blocking layer; 8) Vacuum evaporation is used to deposit an electron injection layer on the electron transport layer; 9) Vacuum evaporation is used to deposit cathode Al on the electron injection layer.

[0133] The cathode and anode of the organic electroluminescent device are connected by a known driving circuit, and the voltage-efficiency-current density relationship of the OLED is tested by a standard method using a Keithley 2400 power supply combined with a PR670 photometer. The device performance of the organic electroluminescent device prepared using BD01 or a diboron polycyclic compound as the luminescent material is shown in Table 2.

[0134] Table 2 Performance parameters of organic electroluminescent devices

[0135]

[0136] Note: External quantum efficiency is a relative value.

[0137] As shown in Table 2, the diboron polycyclic compound of the present invention is applied as a luminescent material to OLED, and has excellent performance. Its relative external quantum efficiency is 5.6% to 26.9% higher than that of the existing material BD01, and the half-peak width is 22 to 29 nm. Compared with the existing material BD01 applied to OLED, after the diboron polycyclic compound of the present invention is applied as a luminescent material to OLED, the luminous efficiency of the light-emitting device is significantly improved, the half-peak width of the emission spectrum is narrower, and the color purity is higher. It has great application value in the application of OLED and has good industrialization prospects.

[0138] The embodiments described above are part of the embodiments of the present invention, rather than all of the embodiments. The detailed description of the embodiments of the present invention is not intended to limit the scope of the invention claimed for protection, but merely represents selected embodiments of the present invention. All other embodiments obtained without creative work and related deductions and substitutions made by ordinary technicians in the field under the conditions of the concept of the present invention belong to the scope of protection of the present invention.

Claims

1. A compound, characterized in that Having a structure as shown in formula (I), ； Y1 in the formula (I) is selected from a single bond, O, S, Se, NR1, CR2R3; In the formula (I), Y2 is the same as Y3, X1 is the same as X2, Ar1 is the same as Ar6, Ar2 is the same as Ar5, and Ar3 is the same as Ar4; In the formula (I), Y2 and Y3 are both selected from one of O, S, Se and NR4; In the formula (I), X1 and X2 are both selected from NR5, O, S, Se, CR6R7; Ar1 to Ar6 in the formula (I) are independently selected from a hydrogen atom, a deuterium atom, a C1-C5 alkyl group, a substituted or unsubstituted amine group, a substituted or unsubstituted C6-C30 aryl group, or a substituted or unsubstituted C6-C30 heteroaryl group; R1 in the NR1 is a substituted or unsubstituted phenyl or biphenyl group; R2 and R3 in the CR2R3 are independently selected from methyl and phenyl; R4 in NR4 and R5 in NR5 are connected to N by a single bond or bonded to an adjacent benzene ring to form a ring; When R4 in NR4 and R5 in NR5 are bonded to adjacent benzene rings to form a ring, R4 is only bonded to the benzene ring having Ar3 and Ar4 substituents to form a ring, and R5 is only bonded to the benzene ring having Ar2 and Ar5 substituents to form a ring.

2. The compound according to claim 1, characterized in that R4 in the NR4 is a substituted or unsubstituted phenyl group.

3. The compound according to claim 1, characterized in that R5 in the NR5 is a substituted or unsubstituted phenyl group; R6 and R7 in the CR6R7 are independently selected from methyl or phenyl.

4. The compound according to claim 1, characterized in that Having the structures shown in A1 to A6, 。 5. The compound according to claim 4, characterized in that The A1 to A6 have the following structures: 。 6. Use of the compound according to any one of claims 1 to 5 in an organic electroluminescent device, characterized in that: The compound is used as a light-emitting layer material in an organic electroluminescent device.

7. An organic electroluminescent device comprising a light-emitting layer, characterized in that: The material of the light-emitting layer includes the compound according to any one of claims 1 to 5.

8. A display component, characterized in that: An organic electroluminescent device comprising the organic electroluminescent device according to claim 7.

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