Boron-containing polycyclic compound for organic luminescent material

Abstract

The invention belongs to the technical field of organic light-emitting materials, and relates to a boron-containing polycyclic compound for an organic light-emitting material. According to the invention, aryl or heteroaryl is taken as a center, 2-3 boron atoms are introduced and form covalent bonds with atoms such as N, O, S and Se, and a rigid polycyclic compound is constructed. The compound provided by the invention is a boron-containing polycyclic compound with multiple resonance effects, can realize narrow-spectrum and high-color-purity luminescence, also has efficient TADF characteristics, and significantly improves the performance of OLED devices. Compared with the prior art, the compound has remarkable advantages in the aspects of molecular structure design, photoelectric property regulation and control, application range and the like, provides important technical support for development of new-generation high-performance OLED materials, and has wide market prospects and application potential.

Description

Technical Field

[0001] The invention belongs to the technical field of organic luminescent materials and relates to a boron-containing polycyclic compound used for organic luminescent materials. Background Art

[0002] Organic electroluminescent elements (OLEDs) are developing rapidly as a new type of solid-state light-emitting technology and have gradually become the mainstream display technology. Organic electroluminescent elements usually have a structure including an anode, a hole injection layer, a hole transport layer, an electron blocking layer, a light-emitting layer, a hole blocking layer, an electron transport layer, an electron injection layer and a cathode. In the above device structure, when an external electric field is applied, holes are injected from the anode into the organic layer, and electrons are injected from the cathode into the organic layer. When the injected holes and electrons meet in the light-emitting layer, excitons are formed. When the excitons re-transition to the ground state, energy is released, thereby emitting light.

[0003] With the rapid iterative development of new display technologies, the market demand for high-quality display effects is increasing. In order to meet this demand, display standards (such as BT.2020) have reached unprecedented heights in terms of device color purity. Taking blue light as an example, its color coordinates are required to reach CIEy=0.046, which places extremely stringent requirements on the half-peak width of the emission spectrum of the luminescent material. Traditional fluorescent materials are difficult to meet this indicator due to their wide spectrum. Therefore, the development of new luminescent materials with narrow spectrum and high color purity has become an important research direction in the field of display technology.

[0004] In this context, the new generation of thermally activated delayed fluorescence materials (MR-TADF) with multiple resonance effects have attracted widespread attention from academia and industry due to their unique molecular configuration and excellent optoelectronic properties. MR-TADF materials achieve multiple resonance effects through the interaction between holes and electrons in molecules, which can significantly reduce the Stokes shift and narrow the emission spectrum, thereby achieving high-color purity luminescence. At the same time, this type of material also has the characteristics of thermally activated delayed fluorescence (TADF), which can simultaneously utilize the energy of singlet states (S1) and triplet states (T1), and convert triplet excitons into singlet excitons through the reverse intersystem crossing (RISC) process. In theory, it can achieve 100% internal quantum efficiency, greatly improving the luminescence efficiency of the device.

[0005] However, the development of high-performance MR-TADF materials, especially blue-light materials, faces many challenges. First, blue-light materials need to have a large band gap, which places high demands on molecular design. Second, in order to achieve efficient TADF properties, the energy level difference between the singlet and triplet states (ΔE st) is usually less than 0.1eV, which places extremely high demands on the fine control of the molecular structure; finally, the realization of the multiple resonance effect requires the molecule to have a specific rigid polycyclic configuration and electron distribution, which poses a huge challenge to synthetic chemistry and molecular engineering. Therefore, how to design and synthesize new MR-TADF materials that simultaneously meet the wide band gap and multiple resonance effects has become a research hotspot and difficulty in the current display material field.

[0006] To solve these problems, researchers are exploring new molecular structures and synthesis strategies by combining theoretical calculations with experiments. For example, introducing atoms such as boron and nitrogen to form a rigid polycyclic structure, or regulating the electron distribution through substituents to achieve synergistic optimization of multiple resonance effects and TADF properties. In addition, device engineering optimization (such as multilayer interface regulation, carrier balance, etc.) is also widely used to further improve the performance of MR-TADF materials.

[0007] In short, as a new generation of luminescent materials, MR-TADF materials have shown great application potential in the field of high-quality display due to their narrow spectrum, high color purity and high efficiency. The boron-containing polycyclic compound of the present invention, as a potential MR-TADF material, not only achieves narrow spectrum emission, but also provides new ideas and solutions for solving key problems in the current development of MR-TADF materials, which has important scientific significance and industrial value. Summary of the invention

[0008] In view of this, the purpose of the present invention is to provide a boron-containing polycyclic compound for organic light-emitting materials, with an aromatic or heteroaryl group as the center, 2 to 3 boron atoms are introduced, and covalent bonds are formed with atoms such as N, O, S, and Se to construct a rigid polycyclic compound, which can be used as a MR-TADF material in organic electroluminescent devices.

[0009] In a first aspect, the present invention provides a compound having a structure as shown in Formula I or Formula II, , ; Wherein, X1 and X2 in Formula I or Formula II are selected from any one of CR1 and N; Y1 and Y2 in Formula I or Formula II are selected from any one of NR2, O, S, and Se; Ar1, Ar2, Ar3, and Ar4 in Formula I or Formula II are selected from any one of H, D, a C1-C5 alkyl group, a substituted or unsubstituted amine group, and a substituted or unsubstituted C6-C30 aryl heteroaryl group.

[0010] Furthermore, in the compounds provided by the present invention, R1 in CR1 is selected from any one of H, D, B, cyano, substituted or unsubstituted amine, substituted or unsubstituted aryl or heteroaryl, or is bonded to an adjacent benzene ring.

[0011] Furthermore, in the compounds provided by the present invention, R2 in the NR2 is a substituted or unsubstituted aryl heteroaryl, or is bonded to the adjacent B by a covalent bond.

[0012] Furthermore, in the compounds provided by the present invention, when Y1 and Y2 are N atoms, they have a structure as shown in Formula III or Formula IV, .

[0013] Furthermore, in the compounds provided by the present invention, when X1 and X2 are CR1 or N, they have structures as shown in Formula A1 to A4 or Formula B1 to B2,

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[0015] Furthermore, the compounds provided by the present invention have the following structure:

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[0063] ; Here, D indicates that the hydrogen atom is substituted with deuterium.

[0064] In a second aspect, the present invention provides use of the above compound in an organic electroluminescent device.

[0065] In a third aspect, the present invention provides use of the above compound in an organic electroluminescent device.

[0066] In a fourth aspect, the present invention provides an organic electroluminescent device, comprising an anode layer, a cathode layer and an organic thin film layer located between the anode layer and the cathode layer, wherein the organic thin film layer comprises a hole injection layer, a hole transport layer, an electron blocking layer, a light-emitting layer, a hole blocking layer, an electron transport layer and an electron injection layer, and the light-emitting layer contains the above-mentioned compound.

[0067] Compared with the prior art, the technical solution provided by the present invention has at least the following beneficial effects or advantages: (1) The present invention constructs a rigid polycyclic compound by introducing two or three boron atoms into aromatic or heteroaromatic molecules and forming covalent bonds with atoms such as N, O, S, and Se. This structure not only makes the molecule have a large degree of twist, but also can effectively regulate the energy of the singlet state (S1) and triplet state (T1), achieving a small singlet-triplet energy level difference (ΔE st ), thereby enhancing the multiple resonance effect and thermally activated delayed fluorescence (TADF) characteristics. The central aromatic or heteroaromatic group participates in conjugation, further improving the charge distribution within the molecule, enhancing the MR-TADF effect, and enabling the material to utilize singlet and triplet excitons simultaneously, theoretically achieving 100% internal quantum efficiency.

[0068] (2) Due to the introduction of the multiple resonance effect, the compounds provided by the present invention can significantly reduce the Stokes shift and narrow the half-peak width of the emission spectrum, thereby achieving luminescence with high color purity.

[0069] (3) The compounds provided by the present invention have suitable HOMO and LUMO energy levels, which can effectively balance the injection and transmission of holes and electrons and improve the recombination efficiency of excitons in the light-emitting layer. Combined with the MR-TADF effect, when the material is used as a light-emitting layer in an organic electroluminescent device (OLED), the luminescence efficiency and external quantum efficiency of the device can be significantly improved.

[0070] (4) The compounds provided by the present invention are not only suitable for OLED light-emitting devices, but can also be widely used in various display devices, such as smart phones, televisions, tablet computers, wearable devices, etc. Its high efficiency, narrow spectrum and high color purity make it have important industrial value in the field of high-quality display and lighting. BRIEF DESCRIPTION OF THE DRAWINGS

[0071] 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 described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0072] Figure 1 Schematic diagram of the structure of an organic electroluminescent element, 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

[0073] The technical scheme of the present invention is described below in conjunction with the examples, but the present invention is not limited to the following examples. The experimental methods and detection methods described in each example are conventional methods unless otherwise specified; the reagents and materials are available on the market unless otherwise specified, and the % in the following examples are all mass percentages unless otherwise specified.

[0074] Preparation Example This preparation example provides the synthesis methods of some intermediates and compounds. The synthesis methods of the remaining intermediates and compounds are similar methods and can be easily synthesized. The specific synthesis routes are shown below.

[0075] Synthesis of intermediate 2:

[0076] Synthesis of intermediate 2: Under nitrogen protection, raw material 1 (30.00 g, 96.7 mmol), raw material 2 (14.47 g, 44.0 mmol), potassium carbonate (18.21 g, 132.0 mmol) and DMF (300 mL) were added to the reaction bottle, and then Pd2(dba)3 (tri(dibenzylideneacetone)dipalladium, 1.61 g, 1.76 mmol), X-Phos (2-dicyclohexylphosphine-2',4',6'-triisopropylbiphenyl, 1.67 g, 3.52 mmol) were added and heated to 120 °C for 4 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. Finally, it was passed through a silica gel column and recrystallized to obtain intermediate 2 (17.35 g, with a yield of 50%).

[0077] Synthesis of compound 1: Under nitrogen protection, add intermediate 2 (15.30 g, 19.4 mmol) and o-dichlorobenzene (50 mL) to a three-necked flask equipped with a condenser, then slowly add boron tribromide (29.10 g, 116.4 mmol) dropwise, and heat to 150°C~160°C for 8 hours. After the reaction, cool the system to room temperature. 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 2 (7.02 g, 45% yield).

[0078] The characterization results of the obtained samples are as follows: HRMS: measured value: 805.4846 [M+H] + ; Exact mass: 805.4859. C 58 H 58 B2N2 (%) calculated value: C, 86.56%; H, 7.27%; N, 3.48%; measured value: C, 86.49%; H, 7.20%; N, 3.38%.

[0079] Synthesis of compound 13:

[0080] The synthesis of intermediate 13-1 refers to the synthesis of intermediate 2, except that raw material 2 is replaced by raw material 3.

[0081] Synthesis of intermediate 13-2: Under nitrogen protection, add intermediate 13-1 (21.00 g, 26.5 mmol) and dichloromethane (200 mL) to a three-necked flask equipped with a condenser, cool to 0°C~5°C, and then slowly add boron tribromide (7.28 g, 29.2 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 finally passed through a silica gel column and recrystallized to obtain intermediate 13-2 (18.23 g, yield 90%).

[0082] The synthesis of compound 13 was based on the synthesis of compound 2, except that intermediate 2 was replaced by intermediate 13-1.

[0083] The characterization results of the obtained samples are as follows: LC-MS: Measured value: 781.4376 [M+H] + ; Exact mass: 781.4383. C 56 H 54 O2B2 (%) calculated value: C, 86.16%; H, 6.97%; measured value: C, 86.07%; H, 6.90%.

[0084] Synthesis of compound 26:

[0085] The synthesis of compound 26 was based on the synthesis of compound 2, except that raw material 2 was replaced by raw material 4.

[0086] Synthesis of compound 33:

[0087] The synthesis of compound 33 referred to the synthesis of compound 13, except that raw material 3 was replaced by raw material 5.

[0088] The characterization results of the obtained samples are as follows: HRMS: measured value: 821.4326 [M+H] + ; Exact mass: 821.4332. C 58 H 54 O3B2 (%) calculated value: C, 84.88%; H, 6.63%; measured value: C, 84.80%; H, 6.54%.

[0089] Synthesis of compound 34:

[0090] The synthesis of compound 34 was based on compound 2, except that raw material 2 was replaced by raw material 6.

[0091] The characterization results of the obtained samples are as follows: HRMS: measured value: 807.4756 [M+H] + ; Exact mass: 807.4764. C 56 H 56 B2N4 (%) calculated value: C, 83.38%; H, 7.00%; N, 6.95%; measured value: C, 83.30%; H, 6.91%; N, 6.88%.

[0092] Synthesis of compound 105:

[0093] The synthesis method of intermediate 105 refers to the synthesis of intermediate 2, except that raw material 2 is replaced by raw material 7.

[0094] Synthesis of compound 105: Under nitrogen protection, add intermediate 105 (15.30 g, 19.4 mmol) and o-dichlorobenzene (50 mL) to a three-necked flask equipped with a condenser, then slowly add boron tribromide (48.4 g, 193.6 mmol) dropwise, and heat to 170°C~180°C for 8 hours. After the reaction, cool the system to room temperature. 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 105 (10.23 g, yield 65%).

[0095] The characterization results of the obtained samples are as follows: HRMS: measured value: 814.4752 [M+H] + ; Exact mass: 814.4760. C 57 H 54 B3N3 (%) calculated value: C, 84.16%; H, 6.69%; N, 5.17%; measured value: C, 84.10%; H, 6.57%; N, 5.06%.

[0096] Synthesis of compound 123:

[0097] Synthesis of Intermediate 123-2 Referring to the synthesis of Compound 105, starting material 7 was replaced by starting material 9 (9.80 g, yield 58%).

[0098] Synthesis of intermediate 123-3: Under nitrogen protection, add intermediate 123-2 (9.5 g, 15.4 mmol), biboronic acid pinacol ester (4.70 g, 18.5 mmol) and decahydronaphthalene (100 mL) to the reaction bottle, then add methoxy (cyclooctadiene) iridium dimer (0.21 g, 0.31 mmol), 4,4′-di-tert-butyl-2,2′-bipyridine (dtbpy, 0.16 g, 0.62 mmol) and heat to 100°C for 16 hours. After the reaction, wash with water, pass through a silica gel column and recrystallize to obtain intermediate 123-3 (6.85 g, yield 60%).

[0099] Synthesis of compound 123: Under nitrogen protection, intermediate 123-3 (6.00 g, 8.1 mmol), raw material 10 (2.15 g, 8.0 mmol), potassium carbonate (1.66 g, 12.0 mmol), dioxane (60 mL) and water (8 mL) were added to the reaction bottle, and then Pd(dppf)Cl2 (1,1'-bis(diphenylphosphino)ferrocenepalladium dichloride, 0.041 g, 0.06 mmol) was added, and the mixture was heated to 90 °C for 6 h. After the reaction, the mixture was cooled to room temperature and poured into water to generate a white precipitate, which was filtered. The precipitate was washed with water and ethanol in turn. Finally, compound 123 (5.10 g, yield 75%) was obtained by silica gel column and recrystallization.

[0100] The characterization results of the obtained samples are as follows: HRMS: measured value: 848.3315 [M+H] + ; Exact mass: 848.3323. C 59 H 36 B3N5 (%) calculated value: C, 83.63%; H, 4.28%; N, 8.26%; measured value: C, 86.50%; H, 7.18%; N, 3.40%.

[0101] Synthesis of compound 189:

[0102] The synthesis of compound 189 was based on the synthesis of compound 2, except that starting material 2 was replaced by starting material 12 (8.50 g, yield 54%).

[0103] The characterization results of the obtained samples are as follows: HRMS: measured value: 806.4806 [M+H] + ; Exact mass: 806.4811. C 57 H 57 B2N3 (%) calculated value: C, 84.97%; H, 7.13%; N, 5.22%; measured value: C, 84.90%; H, 7.05%; N, 5.18%.

[0104] Synthesis of compound 190:

[0105] The synthesis of compound 190 was based on the synthesis of compound 2, except that raw material 2 was replaced by raw material 13 (10.50 g, yield 60%).

[0106] The characterization results of the obtained samples are as follows: HRMS: measured value: 957.5479 [M+H] + ; Exact mass: 957.5485. C 70 H 66B2N2 (%) calculated value: C, 87.86%; H, 6.95%; N, 2.93%; measured value: C, 87.79%; H, 6.86%; N, 2.84%.

[0107] The present invention shows the performance parameters of the synthesized compound 2, compound 10, compound 13, compound 26, compound 33, compound 34, compound 47, compound 52, compound 58, compound 61, compound 68, compound 72, compound 89, compound 93, compound 105, compound 123, compound 134, compound 138, compound 145, compound 152, compound 159, compound 166, compound 176, compound 185, compound 186, compound 189, compound 190 and the existing luminescent material BD01, including T1 energy level, S1, HOMO (highest molecular occupied orbital) and LUMO (lowest molecular unoccupied orbital). HOMO, LUMO, S1 and T1 are 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.

[0108] Table 1 HOMO, LUMO, S1, T1 simulation results

[0109] As can be seen from Table 1, the compounds of the present invention have suitable HOMO energy levels and LUMO energy levels, and the singlet-triplet energy difference (ΔEst) is smaller, and intergap crossing inversion from triplet to singlet occurs more easily.

[0110] Taking some compounds provided by the present invention as examples, the compounds are applied as luminescent host materials to organic electroluminescent devices to verify the excellent effects achieved.

[0111] The excellent effect of the OLED material of the present invention in the device is specifically described in detail through the device performance of Examples 1 to 27 and Comparative Example 1. The structure and manufacturing process of Examples 1 to 27 of the present invention and Comparative Example 1 are exactly the same, and the same glass substrate and electrode material are used, and the film thickness of the electrode material is also consistent. The difference is that the main material of the light-emitting layer is adjusted, as follows.

[0112] Comparative Example 1 This comparative example provides an organic electroluminescent device, the structure of which 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.

[0113] Among them, the substrate 1 is a glass substrate with a thickness of 0.7mm; the material of the anode layer 2 is indium tin oxide (ITO) with high functional function; the material of the hole injection layer 3 is HT1 doped with HI-1, the mass ratio is 95:5, and the thickness is 10nm; the material of the hole transport layer 4 is HT1, the thickness is 60nm; the material of the electron blocking layer 5 is EB1, the thickness is 15nm; the light-emitting layer 6 uses BH1 as the main material and BD01 as the light-emitting material, the doping mass ratio is 5%, and the thickness is 30nm; the material of the hole blocking layer 7 is HB, the thickness is 10nm; the material of the electron transport layer 8 is composed of ET-1 doped with Liq, the doping concentration is w50%, and the thickness is 30nm; the material of the electron injection layer 9 is Liq, the thickness is 2nm; the material of the cathode layer 10 is Al, the thickness is 100nm.

[0114] The basic material structure used in each functional layer of the device is as follows:

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[0116] The specific preparation steps of the above organic electroluminescent device are as follows: (1) Clean the ITO anode layer on the transparent glass or plastic substrate by ultrasonic cleaning with deionized water, acetone, and ethanol for 20 minutes each, and then perform plasma treatment in an oxygen atmosphere for 5 minutes; (2) On the ITO anode layer, a hole injection layer material HT1:HI-1 is deposited by vacuum evaporation with a mass ratio of 97:3 and a thickness of 10 nm. This layer serves as a hole injection layer. (3) Vacuum evaporation of hole transport material HT1 on the hole injection layer with a thickness of 60 nm, which serves as the hole transport layer; (4) Vacuum evaporation is performed on the hole transport layer HT1 to deposit an electron blocking layer material EB1 with a thickness of 15 nm. This layer serves as an electron blocking layer. (5) On the electron blocking layer, a light-emitting layer is deposited by vacuum evaporation or co-evaporation, using BH1 as the main material and RD01 as the light-emitting material, with a doping mass ratio of 5% and a thickness of 30 nm; (6) On the light-emitting layer, a hole blocking material HB is deposited by vacuum evaporation with a thickness of 10 nm. This layer serves as a hole blocking layer. (7) On the hole blocking layer, the electron transport material ET-1:Liq is evaporated by vacuum evaporation with a mass ratio of 1:1 and a thickness of 30 nm. This layer serves as the electron transport layer; (8) On the electron transport layer, the electron injection material Liq is evaporated by vacuum evaporation with a thickness of 2 nm. This layer serves as the electron injection layer; (9) On the electron injection layer, cathode Al is deposited by vacuum evaporation with a thickness of 100 nm. This layer is used as a cathode conductive electrode and is referred to as the cathode layer.

[0117] Embodiments 1 to 27 The implementation process of Examples 1 to 27 is the same as that of Comparative Example 1, except that Compound 2, Compound 10, Compound 13, Compound 26, Compound 33, Compound 34, Compound 47, Compound 52, Compound 58, Compound 61, Compound 68, Compound 72, Compound 89, Compound 93, Compound 105, Compound 123, Compound 134, Compound 138, Compound 145, Compound 152, Compound 159, Compound 166, Compound 179, Compound 185, Compound 186, Compound 189 and Compound 190 provided by the present invention are used as light-emitting layer light-emitting materials instead of the light-emitting layer light-emitting material BD01 described in Comparative Example 1.

[0118] The cathode and anode of each group of organic electroluminescent devices were connected using a known driving circuit, and the voltage-efficiency-current density relationship of the OLED device was tested using a standard method using a Keithley 2400 power supply combined with a PR670 photometer. The test results are shown in Table 2.

[0119] Table 2 Comparison of device light emitting layer composition and device performance in various embodiments

[0120] As can be seen from the data in Table 2, the compounds provided by the present invention are applied as luminescent materials in OLED devices and show excellent performance. Compared with the BD01 material described in Comparative Example 1, the compounds of the present invention have significant advantages in the following aspects: (1) Improved luminous efficiency: When the compounds of the present invention are used as luminescent materials, the luminous efficiency of OLED devices is significantly improved. This is due to the smaller singlet-triplet energy level difference (ΔE st ), so that the excitons can efficiently achieve radiative recombination through the thermally activated delayed fluorescence (TADF) mechanism; (2) Narrower half-peak width: Since the compound of the present invention has a multiple resonance thermally activated delayed fluorescence (MR-TADF) effect, the half-peak width of its emission spectrum is significantly narrowed; (3) Molecular structure advantage: The diboron polycyclic compound provided by the present invention has a highly twisted molecular structure, which not only ensures the rigidity of the compound, but also enhances the multiple resonance effect, further optimizing the photoelectric properties of the material. The compound has suitable HOMO and LUMO energy levels, which can effectively balance the injection and transmission of holes and electrons and improve the overall performance of the device.

[0121] The present invention has successfully developed a class of diboron polycyclic compounds with multiple resonance effects through innovative molecular design. When used as luminescent materials in OLED devices, these compounds show significant advantages of high efficiency, narrow spectrum and high color purity, and have important scientific significance and industrial value.

[0122] As described above, the basic principle, main features and advantages of the present invention are well described. The above embodiments and descriptions are only descriptions of the preferred implementation modes of the present invention, and the present invention is not limited by the above embodiments. Without departing from the spirit and scope of the present invention, various changes and improvements made by ordinary technicians in this field to the technical solution of the present invention should fall within the protection scope determined by the present invention.

Claims

1. A compound, characterized in that Having a structure as shown in Formula I or Formula II, ， ； Wherein, X1 and X2 in Formula I or Formula II are selected from any one of CR1 and N; Y1 and Y2 in Formula I or Formula II are selected from any one of NR2, O, S, and Se; Ar1, Ar2, Ar3, and Ar4 in Formula I or Formula II are selected from any one of H, D, a C1-C5 alkyl group, a substituted or unsubstituted amine group, and a substituted or unsubstituted C6-C30 aryl heteroaryl group.

2. The compound according to claim 1, characterized in that R1 in CR1 is selected from any one of H, D, B, cyano, substituted or unsubstituted amine, substituted or unsubstituted aryl or heteroaryl, or is bonded to an adjacent benzene ring.

3. The compound according to claim 1, characterized in that R2 in the NR2 is a substituted or unsubstituted aryl heteroaryl, or is covalently bonded to the adjacent B.

4. The compound according to claim 1, characterized in that When Y1 and Y2 are N atoms, they have a structure as shown in Formula III or Formula IV, 。 5. The compound according to claim 1, characterized in that When X1 and X2 are CR1 or N, they have the structures shown in Formula A1 to A4 or Formula B1 to B2, 。 6. The compound according to claim 1, characterized in that Has the structure shown below, ； Here, D indicates that the hydrogen atom is substituted with deuterium.

7. Use of the compound according to any one of claims 1 to 6 in an organic electroluminescent device.

8. Use of the compound according to any one of claims 1 to 6 in an organic electroluminescent device.

9. An organic electroluminescent device, comprising an anode layer, a cathode layer and an organic thin film layer located between the anode layer and the cathode layer, wherein the organic thin film layer comprises a hole injection layer, a hole transport layer, an electron blocking layer, a light emitting layer, a hole blocking layer, an electron transport layer and an electron injection layer, characterized in that: The light-emitting layer contains the compound according to any one of claims 1 to 6.

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