A boron-nitrogen polycyclic compound containing a heteroatom silicon group segment and an organic electroluminescent device comprising the same

Abstract

The application belongs to the technical field of OLED, and provides a boron-nitrogen polycyclic compound containing a heteroatom silicon group segment and an organic electroluminescent device containing the same. The structural general formula of the boron-nitrogen polycyclic compound is shown as formula I. In the silicon group segment at the lower end of formula I, a heteroatom group Y (such as Y is dibenzofuran and the like) is added, so that the spin-orbit coupling (SOC) is enhanced, the charge distribution of the whole molecule is finely controlled, the oscillator strength (f) is affected, the radiation transition rate (kr) is improved, the exciton annihilation is avoided to slow down the efficiency roll-off, and thus the device light-emitting efficiency is significantly improved, and the device lifetime is improved.

Description

Technical Field

[0001] This invention belongs to the field of OLED technology, specifically including a boron-nitrogen polycyclic compound containing heteroatom silicon-based segments and an organic electroluminescent device containing the same. Background Technology

[0002] With the rapid development of display technology and optoelectronic materials, organic light-emitting diodes (OLEDs) have become a core application technology in mobile phones, tablets, televisions, lighting, and other fields due to their significant advantages such as low voltage, high brightness, wide viewing angle, fast response, good temperature adaptability, and flexible fabrication. The performance improvement of OLED devices hinges on the innovation of organic electroluminescent functional materials. Blue fluorescent dopant materials, as a key component of the OLED emissive layer, directly determine the device's luminous efficiency, color purity, and lifespan, representing a long-standing technological challenge in the industry. The oscillator strength (f) of the doped material in the emissive layer is a core photophysical parameter that determines the exciton radiative transition rate and luminous efficiency. Theoretically, higher oscillator strength is beneficial for obtaining a large radiative transition rate constant (kr), thereby improving the material's photoluminescence quantum yield (PLQY) and the device's internal quantum efficiency (IQE).

[0003] However, there are relatively few suitable structural design strategies at present. Some cannot effectively increase f, while others easily make f too high. If the oscillator strength is too low, the transition dipole moment is weak and the radiative transition rate is insufficient, resulting in a large number of excitons being dissipated in a non-radiative form, making it difficult to meet the requirements of the external quantum efficiency (EQE) of the device. If the oscillator strength is too high, although high luminous efficiency can be temporarily obtained under high brightness, the excessively fast exciton recombination will significantly increase the exciton density in the light-emitting layer. Under high current density, it is very easy to induce exciton-exciton annihilation (TTA) and exciton-polaron quenching (TPQ), causing a serious efficiency roll-off phenomenon. At the same time, it accelerates material aging and significantly shortens the device's operating life. Currently, there are no reports on improving device performance by precisely controlling the oscillator strength of the doped material.

[0004] Therefore, there is an urgent need to develop a doped material with suitable oscillator strength to improve the luminous efficiency of organic electroluminescent devices. Summary of the Invention

[0005] In view of this, the present invention provides a boron-nitrogen polycyclic compound containing heteroatom silicon-based segments and an organic electroluminescent device containing the same. This invention addresses the aforementioned industry pain points and technological gaps, aiming to develop a blue fluorescent doping material that balances exciton recombination rate and rapid exciton radiative transitions. Through molecular structure design, by introducing heteroatom silicon-based segments, the oscillator strength (f between 0.35 and 0.6) of the boron-nitrogen polycyclic compound is precisely controlled; this effectively enhances radiative transitions, directly increasing the luminescence quantum yield, thereby improving luminescence efficiency and maintaining device lifetime.

[0006] To achieve the above-mentioned objectives, the present invention adopts the following technical solution: The first aspect of this invention provides a boron-nitrogen polycyclic compound containing heteroatom silicon-based segments, the general structural formula of which is shown in Formula I: I; Each time R1 appears, it independently represents any one of the following: hydrogen, deuterium, halogen, substituted or unsubstituted alkyl group with C1 to C30 carbon atoms, substituted or unsubstituted cycloalkyl group with C3 to C30 carbon atoms, substituted or unsubstituted aryl group with C6 to C60 carbon atoms, substituted or unsubstituted heteroaryl group with C5 to C60 carbon atoms, substituted or unsubstituted fused-ring aryl group with C6 to C60 carbon atoms, substituted or unsubstituted heterofused-ring aryl group with C5 to C60 carbon atoms, and substituted or unsubstituted amino group with C1 to C30 carbon atoms. Two or more R1s can be connected to each other to form an aliphatic ring, an aromatic ring, or a fused ring. Each time R2 appears, it independently represents any one of the following: hydrogen, deuterium, halogen, substituted or unsubstituted alkyl group with C1 to C30 carbon atoms, substituted or unsubstituted cycloalkyl group with C3 to C30 carbon atoms, substituted or unsubstituted aryl group with C6 to C60 carbon atoms, substituted or unsubstituted heteroaryl group with C5 to C60 carbon atoms, substituted or unsubstituted fused-ring aryl group with C6 to C60 carbon atoms, and substituted or unsubstituted heterofused-ring aryl group with C5 to C60 carbon atoms. Two or more R2s can be connected to each other to form an aliphatic ring, an aromatic ring, or a fused ring. Each time R appears, it independently represents any one of the following: a substituted or unsubstituted aryl group with C6 to C60 carbon atoms, a substituted or unsubstituted heteroaryl group with C5 to C60 carbon atoms, a substituted or unsubstituted fused-ring aryl group with C6 to C60 carbon atoms, or a substituted or unsubstituted heterofused-ring aryl group with C5 to C60 carbon atoms. m and n each independently represent 0, 1, 2, 3 or 4; X represents O or S; Each time Y appears, it independently represents any one of the following: a substituted or unsubstituted aryl group with C6 to C30 carbon atoms, a substituted or unsubstituted heteroaryl group with C5 to C30 carbon atoms, or a substituted or unsubstituted heterofused aryl group with C5 to C30 carbon atoms. At least one Y represents a substituted or unsubstituted heteroaryl group with C5 to C30 carbon atoms or a substituted or unsubstituted heterofused aryl group with C5 to C30 carbon atoms. When R1, R2, and R contain substituents, the substituents are selected from any one of alkyl groups having C1 to C10 carbon atoms, cycloalkyl groups having C3 to C30 carbon atoms, aryl groups having C6 to C20 carbon atoms, and heteroaryl groups having C5 to C60 carbon atoms; two or more of the substituents can be linked together to form an aliphatic ring; When Y contains a substituent, the substituent is selected from any one of alkyl groups having C1 to C10 carbon atoms, cycloalkyl groups having C3 to C30 carbon atoms, aryl groups having C6 to C20 carbon atoms, and heteroaryl groups having C5 to C60 carbon atoms; two or more of the substituents may be linked together to form an aliphatic ring; In Formula I, any hydrogen atom can be substituted with deuterium.

[0007] Furthermore, X represents O.

[0008] Furthermore, each time R appears, it independently represents any one of the following: a substituted or unsubstituted aryl group with C6 to C30 carbon atoms, or a substituted or unsubstituted heteroaryl group with C5 to C20 carbon atoms.

[0009] Furthermore, each time R appears, it independently represents a substituted or unsubstituted aryl group with a carbon number of C6 to C20.

[0010] Furthermore, each time R appears, it independently represents any one of substituted or unsubstituted phenyl, substituted or unsubstituted biphenyl, or substituted or unsubstituted terphenyl.

[0011] Furthermore, each time R1 appears, it independently represents any one of the following: a substituted or unsubstituted alkyl group with C1 to C10 carbon atoms, a substituted or unsubstituted aryl group with C6 to C30 carbon atoms, a substituted or unsubstituted heteroaryl group with C5 to C30 carbon atoms, or a substituted or unsubstituted amino group with C1 to C30 carbon atoms. Each time R2 appears, it independently represents any one of the following: a substituted or unsubstituted alkyl group with C1 to C10 carbon atoms, a substituted or unsubstituted aryl group with C6 to C30 carbon atoms, or a substituted or unsubstituted heteroaryl group with C5 to C30 carbon atoms. Two or more R1 and R2 can connect with each other to form a fatty ring.

[0012] Furthermore, each time R1 appears, it independently represents any one of the following: a substituted or unsubstituted alkyl group with C1 to C10 carbon atoms, or a substituted or unsubstituted aryl group with C6 to C30 carbon atoms. Each time R2 appears, it independently represents any one of the following: a substituted or unsubstituted alkyl group with C1 to C10 carbon atoms, or a substituted or unsubstituted aryl group with C6 to C30 carbon atoms.

[0013] Furthermore, each time R1 appears, it independently represents any one of the following: a substituted or unsubstituted alkyl group (e.g., methyl, ethyl, tert-butyl) with C1 to C10 carbon atoms, or a substituted or unsubstituted aryl group (e.g., phenyl) with C6 to C20 carbon atoms. Each time R2 appears, it independently represents any one of the following: a substituted or unsubstituted alkyl group (e.g., methyl, ethyl, tert-butyl) with C1 to C10 carbon atoms, or a substituted or unsubstituted aryl group (e.g., phenyl) with C6 to C20 carbon atoms.

[0014] Furthermore, each occurrence of Y independently represents one of the following structures: , , , , , , , , , , , , , , , , , , , .

[0015] Furthermore, the general structural formula of the boron-nitrogen polycyclic compound is shown in one of the following: I-1 I-2 I-3 I-4 I-5 I-6 I-7 I-8; R3 represents one of the following structures: , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , ; R4 represents one of the following structures: , , , , , , , , , , , ; Any one of the hydrogen atoms in the above groups can be replaced by deuterium, alkyl, cycloalkyl, aryl or heteroaryl. When more than one hydrogen atom is replaced, two adjacent alkyl groups can be linked to form a ring structure. Y1 and Y2 independently represent substituted or unsubstituted aryl groups with C6 to C20 carbon atoms; Y3 represents a substituted or unsubstituted heteroaryl group with a carbon number of C5 to C20, or a substituted or unsubstituted heterofused aryl group with a carbon number of C5 to C20.

[0016] Furthermore, R3 represents one of the following structures: , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , .

[0017] Furthermore, R3 represents one of the following structures: , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , .

[0018] Furthermore, R4 represents one of the following structures: , , , , , , , , , .

[0019] Furthermore, R4 represents one of the following structures: , , , , , , .

[0020] Furthermore, Y1 and Y2 each independently represent one of the following structures: , , ; Y3 represents one of the following structures: , , , , , , , , , , , , , , , , .

[0021] Furthermore, Y3 represents one of the following structures: , , , , , , , , , .

[0022] Furthermore, Y3 represents one of the following structures: , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , .

[0023] Furthermore, each occurrence of R1 is represented independently. , , , Any one of them; Each time R5 appears, it independently represents any one of hydrogen, alkyl, or cycloalkyl, and adjacent R5s can be connected to form a ring structure. R6 and R7 represent any one of hydrogen, alkyl, or aryl groups, respectively. Two adjacent R1s can be connected to each other to form a ring structure; p represents 0, 1, or 2; R2 represents each independently. , , , , Any one of them; Each time R8 appears, it independently represents any one of hydrogen, alkyl, or cycloalkyl, and adjacent R8s can be connected to form a ring structure. Two adjacent R2s can be connected to each other to form a ring structure; q represents 0, 1, and 2.

[0024] Furthermore, R2 represents each independently. , , , Any one of them.

[0025] Furthermore, the boron-nitrogen polycyclic compound is selected from the structures shown below:

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[0116] A second aspect of the present invention provides an organic electroluminescent device, the organic electroluminescent device comprising an anode, a hole transport region, a light-emitting layer, an electron transport region and a cathode sequentially disposed on a substrate; wherein the light-emitting layer comprises one or more boron-nitrogen polycyclic compounds as described above.

[0117] Furthermore, the light-emitting layer comprises a host material and a dopant material, wherein the dopant material comprises one or more boron-nitrogen polycyclic compounds as described above.

[0118] Furthermore, the content of the main material in the light-emitting layer should be greater than 50 wt%, preferably greater than 90 wt%.

[0119] Furthermore, the content of doped material in the light-emitting layer should be less than 20 wt%, preferably less than 5 wt%.

[0120] Furthermore, the hole transport region includes at least one functional layer for transmitting holes, such as a hole transport layer, a light emission auxiliary layer, etc.

[0121] The beneficial effects of this invention are as follows: This invention addresses the contradiction in luminescent molecules where high oscillator strength leads to exciton annihilation, while low oscillator strength results in insufficient radiative rate. The oscillator strength is precisely controlled within the range of 0.35-0.6 by varying the types and amounts of different non-conjugated heteroarylsilane groups introduced into the luminescent nucleus, ensuring a radiative transition rate (kr) > 10. 7 s 1 This improves exciton utilization, reduces exciton aggregation-induced quenching, significantly enhances the luminescence efficiency of the material, and maintains the device's working life, meeting the commercialization needs of luminescent materials. Attached Figure Description

[0122] The specific embodiments of the present invention will be described in further detail below with reference to the accompanying drawings.

[0123] Figure 1This is a schematic diagram of the structure of an organic electroluminescent device containing the compounds of the present invention; wherein, 1-substrate, 2-anode, 3-hole injection layer, 4-hole transport layer, 5-light-emitting auxiliary layer, 6-light-emitting layer, 7-hole blocking layer, 8-electron transport layer, 9-electron injection layer, 10-cathode, and 11-capping layer.

[0124] Figure 2 The NMR spectrum of compound B6 prepared in Synthesis Example 6 is shown below. Figure 2 In the image, A is the complete NMR spectrum of compound B6, and B is a magnified view of a portion of it.

[0125] Figure 3 The NMR spectrum of compound B11 prepared in Synthesis Example 11 is shown below. Figure 3 In the image, A is the complete NMR spectrum of compound B11, and B is a magnified view of a portion of it.

[0126] Figure 4 The NMR spectrum of compound B13 prepared in Synthesis Example 13 is shown below. Figure 4 In the image, A is the complete NMR spectrum of compound B13, and B is a magnified view of a portion of it.

[0127] Figure 5 The NMR spectrum of compound B17 prepared in Synthesis Example 17 is shown below. Figure 5 In the image, A is the complete NMR spectrum of compound B17, and B is a magnified view of a portion of it. Detailed Implementation

[0128] To more clearly illustrate the present invention, the following description, in conjunction with preferred embodiments and accompanying drawings, further clarifies the invention. Similar components in the drawings are indicated by the same reference numerals. Those skilled in the art should understand that the specific description below is illustrative rather than restrictive and should not be construed as limiting the scope of protection of the present invention. The embodiments and comparative examples in this specification are provided to provide a more complete explanation of the specification to those skilled in the art. Various modifications can be made based on the embodiments and comparative examples in this specification, and the scope of protection of the present invention should not be limited to the embodiments and comparative examples detailed below.

[0129] The compounds of this invention are applicable to light-emitting elements, display panels, and electronic devices, particularly organic electroluminescent devices. The electronic devices of this invention are devices comprising a layer of at least one organic compound, and may also comprise layers of inorganic materials or layers formed entirely of inorganic materials. Preferred electronic devices include organic electroluminescent devices (OLEDs), organic integrated circuits (O-ICs), organic field-effect transistors (O-FETs), organic thin-film transistors (O-TFTs), organic light-emitting transistors (O-LETs), organic solar cells (O-SCs), organic dye-sensitized solar cells (O-DSSCs), organic optical detectors, organic photosensors, organic field quenching devices (O-FQDs), light-emitting electrochemical cells (LECs), organic laser diodes (O-lasers), and organic plasma emitting devices. Organic electroluminescent devices (OLEDs) are particularly preferred.

[0130] To better understand the content of this invention, the boron-nitrogen polycyclic compounds containing heteroatom silicon-based segments, the preparation method of the compounds, and the luminescent properties of the devices will be explained in detail with reference to embodiments. Various chemical reactions can be applied to the synthesis method of the compounds according to one embodiment of this invention. However, it should be noted that the synthesis method of the compounds according to one embodiment of this invention is not limited to the synthesis method described below. Unless otherwise stated, subsequent synthesis is carried out in an anhydrous solvent under a protective gas atmosphere. Solvents and reagents can be purchased from conventional reagent suppliers. The compounds of this invention are prepared using representative reactions such as the Buchwald-Hartwig coupling reaction, the Suzuki coupling reaction, or the Heck coupling reaction.

[0131] Synthesis of intermediates

[0132] The general formula for intermediate synthesis is shown above. The target intermediate can be obtained through a two-step Buchwald-Hartwig coupling synthesis method, as illustrated in the following example:

[0133] Compound C1 (87.13 g), compound D1 (16.50 g), and sodium tert-butoxide (29.40 g) were added to toluene (800 ml). Then, under nitrogen protection, bis(dibenzylacetone)palladium (1.83 g) and 2-dicyclohexylphosphine-2',6'-dimethoxybiphenyl (1.64 g) were introduced. The reaction system was then heated to reflux and maintained for 80 hours. After cooling to room temperature, the mixture was quenched with water and separated. The organic phase was filtered and dried over anhydrous sodium sulfate. The solvent was removed by rotary evaporation, and the crude product was purified by column chromatography. The final product was E1: 87.70 g, MS (m / z) (M+): 985.42.

[0134] Compound E1 (87.70 g), compound F1 (53.27 g), and sodium tert-butoxide (26.17 g) were added to toluene (800 ml). Then, under nitrogen protection, bis(dibenzylacetone)palladium (1.65 g) and XantPhos (1.54 g) were introduced. The reaction system was then heated to reflux and maintained for 15 hours. After cooling to room temperature, the mixture was quenched with water and separated. The organic phase was filtered and dried over anhydrous sodium sulfate. The solvent was removed by rotary evaporation, and the crude product was purified by column chromatography. The final product A1 was obtained: 89.47 g, MS (m / z) (M+): 1256.57.

[0135] The preparation of intermediates A2-A30 is carried out in accordance with the above process, and will not be repeated here.

[0136] Synthesis Example 1

[0137] The system was maintained at -30 to -40°C under nitrogen protection. A 24 mL solution of n-butyllithium was slowly added dropwise to a 260 mL solution of tert-butylbenzene containing compound A1 (37.63 g), followed by heating to 60°C and stirring for 6 hours. Then... After adding boron tribromide (5.66 mL) dropwise at 30 °C, the reaction system was stirred at 60 °C for 6 hours. Finally, N,N-diisopropylethylamine (9.80 mL) was added at 0 °C, and the reaction system was stirred at room temperature for 2 hours. 150 mL of deionized water was added to the reaction system to quench residual boron tribromide. The mixture was extracted with 200 mL of dichloromethane, the organic layers were combined, concentrated under vacuum, and purified by column chromatography with a mixed eluent of dichloromethane / petroleum ether (1:20, v / v). The crude product was recrystallized from n-heptane, acetone, and toluene to finally give product B1: 2.13 g, yield: 6%, MS (m / z) (M+H): 1186.18.

[0138] Synthesis Example 2

[0139] The preparation method was the same as in Example 1, except that compound A2 (37.51 g; 30 mmol) was used to replace compound A1, and the final product B2 was obtained: 2.83 g, yield: 8%, MS (m / z) (M+H): 1180.22.

[0140] Synthesis Example 3

[0141] The preparation method was the same as in Example 1, except that compound A3 (40.64 g; 30 mmol) was used to replace compound A1, and the final product B3 was 2.69 g, yield: 7%, MS (m / z) (M+H): 1284.32.

[0142] Synthesis Example 4

[0143] The preparation method was the same as in Example 1, except that compound A4 (40.64 g; 30 mmol) was used to replace compound A1, and the final product B4 was obtained: 2.69 g, yield: 7%, MS (m / z) (M+H): 1284.31.

[0144] Synthesis Example 5

[0145] The preparation method was the same as in Example 1, except that compound A5 (39.10 g; 30 mmol) was used to replace compound A1, and the final product B5 was 2.58 g, yield: 7%, MS (m / z) (M+H): 1233.14.

[0146] Synthesis Example 6

[0147] The preparation method was the same as in Example 1, except that compound A6 (39.31 g; 30 mmol) was used instead of compound A1, resulting in product B6: 2.60 g, yield: 7%, MS (m / z) (M+H): 1240.25. The NMR spectrum of compound B6 is shown below. Figure 2 .

[0148] 1 H NMR (400 MHz, Chloroform- d ) δ 8.65 (d, J = 13.1 Hz, 1H), 7.90 (s,1H), 7.81 (s, 1H), 7.64 (dd, J = 10.5, 7.7 Hz, 1H), 7.54 – 7.46 (m, 3H), 7.40– 7.34 (m, 5H), 7.31 – 7.27 (m, 8H), 7.20 – 7.15 (m, 3H), 7.10 (d, J = 8.1 Hz, 1H), 7.02 (d, J= 8.3 Hz, 1H), 6.97 – 6.84 (m, 4H), 6.84 – 6.70 (m, 5H), 6.67– 6.51 (m, 3H), 6.44 (d, J = 9.1 Hz, 1H), 6.34 (s, 1H), 6.13 (d, J = 13.3 Hz, 1H), 1.63 (dd, J = 13.8, 8.2 Hz, 4H), 1.45 – 1.38 (m, 6H), 1.32 (d, J = 4.0 Hz, 9H), 1.19 (d, J = 11.8 Hz, 9H), 1.08 (d, J = 3.0 Hz, 9H), 1.03 – 0.97 (m, 6H). Synthesis Example 7

[0149] The preparation method was the same as in Example 1, except that compound A7 (44.79 g; 30 mmol) was used to replace compound A1, and the final product B7 was obtained: 3.83 g, yield: 9%, MS (m / z) (M+H): 1422.47.

[0150] Synthesis Example 8

[0151] The preparation method was the same as in Example 1, except that compound A8 (41.54 g; 30 mmol) was used to replace compound A1, and the final product B8 was obtained: 3.15 g, yield: 8%, MS (m / z) (M+H): 1314.36.

[0152] Synthesis Example 9

[0153] The preparation method was the same as in Example 1, except that compound A9 (45.12 g; 30 mmol) was used to replace compound A1, and the final product B9 was obtained: 2.57 g, yield: 6%, MS (m / z) (M+H): 1433.51.

[0154] Synthesis Example 10

[0155] The preparation method was the same as in Example 1, except that compound A10 (45.63 g; 30 mmol) was used to replace compound A1, and the final product B10 was obtained: 3.47 g, yield: 8%, MS (m / z) (M+H): 1450.51.

[0156] Synthesis Example 11

[0157] The preparation method was the same as in Example 1, except that compound A11 (43.48 g; 30 mmol) was replaced with compound A1, resulting in product B11: 2.75 g, yield: 7%, MS (m / z) (M+H): 1314.36. The NMR spectrum of compound B11 is shown below. Figure 3 .

[0158] 1 H NMR (400 MHz, Chloroform- d ) δ 8.76 (d, J = 2.5 Hz, 1H), 8.28 (s,1H), 7.98 (d, J = 7.8 Hz, 1H), 7.89 (d, J = 7.9 Hz, 1H), 7.76 (d, J = 7.9 Hz, 1H), 7.71 (d, J = 8.6 Hz, 1H), 7.66 – 7.61 (m, 1H), 7.53 (d, J = 2.3 Hz, 1H),7.50 – 7.46 (m, 7H), 7.45 (t, J = 2.0 Hz, 2H), 7.44 – 7.40 (m, 1H), 7.39 (d, J = 2.3 Hz, 2H), 7.38 – 7.33 (m, 4H), 7.31 (s, 1H), 7.29 – 7.28 (m, 2H), 7.28 –7.22 (m, 5H), 6.95 (t, J = 1.9 Hz, 1H), 6.82 – 6.72 (m, 4H), 6.61 (d, J = 9.0Hz, 1H), 6.13 (d, J = 1.8 Hz, 1H), 1.46 (s, 9H), 1.37 (s, 9H), 1.36 (s, 18H), 0.89 (s, 18H). Synthesis Example 12

[0159] The preparation method was the same as in Example 1, except that compound A12 (39.26 g; 30 mmol) was used to replace compound A1, and the final product B12 was obtained: 3.34 g, yield: 9%, MS (m / z) (M+H): 1238.31.

[0160] Synthesis Example 13

[0161] The preparation method was the same as in Example 1, except that compound A13 (41.06 g; 30 mmol) was used instead of compound A1, resulting in product B13: 2.72 g, yield: 7%, MS (m / z) (M+H): 1298.34. The NMR spectrum of compound B13 is shown below. Figure 4 .

[0162] 1 H NMR (400 MHz, Chloroform- d ) δ 8.64 (d, J = 2.5 Hz, 1H), 7.97 – 7.88(m, 2H), 7.59 (d, J = 8.6 Hz, 1H), 7.55 – 7.50 (m, 1H), 7.44 (d, J = 2.3 Hz,1H), 7.42 – 7.36 (m, 4H), 7.34 – 7.27 (m, 4H), 7.27 – 7.22 (m, 4H), 7.21 (d, J = 5.5 Hz, 1H), 7.18 (t, J = 3.1 Hz, 4H), 7.16 – 7.08 (m, 8H), 7.06 – 7.00 (m,1H), 6.86 (d, J = 1.9 Hz, 1H), 6.69 (d, J = 1.8 Hz, 2H), 6.64 (d, J = 4.8 Hz, 2H), 6.49 (d, J = 9.0 Hz, 1H), 5.96 (d, J= 1.9 Hz, 1H), 1.36 (s, 9H), 1.32 (s, 9H), 1.30 (s, 9H), 1.26 (s, 9H), 0.81 (s, 18H). Synthesis Example 14

[0163] The preparation method was the same as in Example 1, except that compound A14 (38.17 g; 30 mmol) was used to replace compound A1, and the final product B14 was 3.60 g, yield: 10%, MS (m / z) (M+H): 1202.21.

[0164] Synthesis Example 15

[0165] The preparation method was the same as in Example 1, except that compound A15 (38.29 g; 30 mmol) was used to replace compound A1, and the final product B15 was obtained: 2.16 g, yield: 6%, MS (m / z) (M+H): 1206.54.

[0166] Synthesis Example 16

[0167] The preparation method was the same as in Example 1, except that compound A16 (40.91 g; 30 mmol) was used to replace compound A1, and the final product B16 was 3.48 g, yield: 9%, MS (m / z) (M+H): 1293.23.

[0168] Synthesis Example 17

[0169] The preparation method was the same as in Example 1, except that compound A17 (39.31 g; 30 mmol) was used instead of compound A1, resulting in product B17: 2.23 g, yield: 6%, MS (m / z) (M+H): 1240.25. The NMR spectrum of compound B17 is shown below. Figure 5 .

[0170] 1 H NMR (400 MHz, Chloroform- d ) δ 8.74 (d, J = 13.1 Hz, 1H), 7.99 (dd, J = 7.7, 3.7 Hz, 1H), 7.85 (dd, J= 7.6, 3.4 Hz, 1H), 7.62 – 7.56 (m, 2H), 7.55– 7.48 (m, 4H), 7.48 – 7.44 (m, 1H), 7.43 – 7.41 (m, 2H), 7.38 (d, J = 7.9 Hz, 6H), 7.36 – 7.32 (m, 2H), 7.31 (s, 1H), 7.30 – 7.25 (m, 4H), 7.21 (d, J = 8.2Hz, 1H), 7.14 (d, J = 8.2 Hz, 1H), 7.09 – 7.03 (m, 2H), 7.02 – 6.96 (m, 2H), 6.92 (t, J = 7.6 Hz, 1H), 6.89 – 6.81 (m, 3H), 6.73 (d, J = 7.6 Hz, 1H), 6.68(d, J = 7.6 Hz, 1H), 6.54 (s, 1H), 6.38 (d, J = 27.1 Hz, 1H), 6.24 (d, J = 9.0Hz, 1H), 1.79 – 1.66 (m, 4H), 1.56 – 1.46 (m, 6H), 1.42 (d, J = 2.1 Hz, 9H), 1.33 (d, J = 12.8 Hz, 9H), 1.17 (d, J = 4.7 Hz, 9H), 1.14 – 1.06 (m, 6H). Synthesis Example 18

[0171] The preparation method was the same as in Example 1, except that compound A18 (37.40 g; 30 mmol) was used to replace compound A1, and the final product B18 was 2.11 g, yield: 6%, MS (m / z) (M+H): 1176.27.

[0172] Synthesis Example 19

[0173] The preparation method was the same as in Example 1, except that compound A19 (38.65 g; 30 mmol) was used to replace compound A1, and the final product B19 was obtained: 3.65 g, yield: 10%, MS (m / z) (M+H): 1218.26.

[0174] Synthesis Example 20

[0175] The preparation method was the same as in Example 1, except that compound A20 (39.31 g; 30 mmol) was used to replace compound A1, and the final product B20 was obtained: 2.23 g, yield: 6%, MS (m / z) (M+H): 1240.25.

[0176] Synthesis Example 21

[0177] The preparation method was the same as in Example 1, except that compound A21 (41.60 g; 30 mmol) was used to replace compound A1, and the final product B21 was obtained: 3.55 g, yield: 9%, MS (m / z) (M+H): 1316.3.

[0178] Synthesis Example 22

[0179] The preparation method was the same as in Example 1, except that compound A22 (38.90 g; 30 mmol) was used to replace compound A1, and the final product B22 was obtained: 2.57 g, yield: 7%, MS (m / z) (M+H): 1226.32.

[0180] Synthesis Example 23

[0181] The preparation method was the same as in Example 1, except that compound A23 (34.63 g; 30 mmol) was used to replace compound A1, and the final product B23 was obtained: 2.92 g, yield: 9%, MS (m / z) (M+H): 1084.19.

[0182] Synthesis Example 24

[0183] The preparation method was the same as in Example 1, except that compound A24 (38.02 g; 30 mmol) was replaced with compound A1, and the final product B24 was obtained: 3.58 g, yield: 10%, MS (m / z) (M+H): 1197.22.

[0184] Synthesis Example 25

[0185] The preparation method was the same as in Example 1, except that compound A25 (40.84 g; 30 mmol) was replaced with compound A1, and the final product B25 was obtained: 2.70 g, yield: 7%, MS (m / z) (M+H): 1291.20.

[0186] Synthesis Example 26

[0187] The preparation method was the same as in Example 1, except that compound A26 (36.67 g; 30 mmol) was used to replace compound A1, and the final product B26 was obtained: 3.10 g, yield: 9%, MS (m / z) (M+H): 1152.19.

[0188] Synthesis Example 27

[0189] The preparation method was the same as in Example 1, except that compound A27 (36.67 g; 30 mmol) was replaced with compound A1, and the final product B27 was obtained: 3.45 g, yield: 10%, MS (m / z) (M+H): 1152.19.

[0190] Synthesis Example 28

[0191] The preparation method was the same as in Example 1, except that compound A28 (37.93 g; 30 mmol) was replaced with compound A1, and the final product B28 was obtained: 3.57 g, yield: 10%, MS (m / z) (M+H): 1194.25.

[0192] Synthesis Example 29

[0193] The preparation method was the same as in Example 1, except that compound A29 (37.45 g; 30 mmol) was replaced with compound A1, and the final product B29 was obtained: 3.53 g, yield: 10%, MS (m / z) (M+H): 1178.21.

[0194] Synthesis Example 30

[0195] The preparation method was the same as in Example 1, except that compound A30 (37.93 g; 30 mmol) was used to replace compound A1, and the final product B30 was obtained: 2.86 g, yield: 8%, MS (m / z) (M+H): 1194.24.

[0196] Comparative Example The following are some compounds that were tested during the research process, with their specific structural formulas as follows: .

[0197] Compound performance evaluation Adding aromatic ring silicon-based fragments to compounds can enhance oscillator strength (f), which directly determines the upper limit of device efficiency, but is also subject to constraints from factors such as stability and color purity. Furthermore, the introduction of heteroatom groups into the silicon-based fragments allows for fine-tuning of the f value and its related photophysical properties (such as kr and RISC rate). By enhancing spin-orbit coupling (SOC), kr is increased, and exciton annihilation is avoided to mitigate roll-off.

[0198] 1. Using Gauss16 software and density functional theory (DFT) calculations (basis set level set to: B3LYP / 6-63G(d)), the oscillator strength (f) of the compounds in the synthetic examples and comparative examples was obtained, and the spontaneous emission rate (kr) was calculated. The calculation results are shown in Table 1. f is the actual calculated value, and kr is normalized to 100% using compound B9 as the baseline.

[0199] kr ≈ 1.5 × f × E 2 In the formula, E is the transition energy (eV).

[0200] This indicates that increasing f can accelerate kr, which is a direct way to improve the photoluminescence quantum yield (PLQY) and intra-device quantum efficiency (IQE) of materials.

[0201] 2. Photoluminescent quantum yield (PLQY) test The compounds of this invention and the comparative compounds were dissolved in chromatographic grade toluene to prepare solutions with a concentration of 1.0 × 10⁻⁶. - 5 A dilute solution of mol / L was prepared. Weighing was performed using a microbalance (accuracy ±0.01 mg) to ensure a relative concentration error of <1%. After thorough dissolution by ultrasonic agitation, the solution was filtered through a 0.22 μm polytetrafluoroethylene (PTFE) membrane and transferred to a four-sided transparent quartz cuvette with a 1 cm optical path length. The cuvette was then sealed and ready for analysis. All operations were performed at room temperature (25 ± 2 °C) under dark conditions.

[0202] The tests were performed using a fluorescence spectrophotometer. The excitation wavelength was set to the maximum absorption wavelength (λ) in the UV-Vis absorption spectrum of the sample.abs Alternatively, if multiple absorption bands exist, the excitation wavelength corresponding to the expected charge transfer or local transition is selected. The emission spectrum scan range is 300 nm to 700 nm. The excitation and emission slit widths are both set to 1.0 nm to 2.0 nm, with a scan step size of 1 nm. An integrating sphere is used to record PLQY (measured values), and the excitation spectrum (wavelength range 300 nm to 800 nm) is scanned to confirm its consistency with the absorption spectrum.

[0203] Table 1

[0204] Compared to comparative compound D4, the compounds in the synthetic examples, with the addition of a sterically hindered aromatic ring silicon segment at the boron para-position of the molecular core and the presence of heteroatoms, significantly improve the molecular oscillator strength, enhance the radiative transition rate, and reduce non-radiative energy loss caused by vibrational relaxation during excitation. Compared to comparative compounds D1 and D3, the addition of a heteroatom-containing aromatic ring silicon segment at the boron para-position of the molecular core significantly enhances the radiative transition rate and improves PLQY. In comparative compound D2, the boron para-position also contains a heteroatom-containing aromatic amine segment, which further strengthens the oscillator strength. High oscillator strength typically implies higher exciton density and faster exciton recombination rate, which exacerbates exciton-exciton annihilation (TTA) and exciton-polaron quenching (TPQ), leading to a decrease in PLQY.

[0205] Device Examples The anode in the following embodiments uses anode materials commonly used in the art, such as ITO, Ag, or their multilayer structures. The hole injection unit uses hole injection materials commonly used in the art, with the addition of F4TCNQ, HATCN, NDP-9, etc., for doping. The hole transport unit uses hole transport materials commonly used in the art. The light-emitting unit uses light-emitting materials commonly used in the art; for example, it can be composed of a host material and an emitting guest material, where the emitting guest material can be an organic material such as a pyrene compound, or a metal complex (such as metal Ir, Pt, etc.). The electron transport unit uses electron transport materials commonly used in the art. The electron injection layer uses electron injection materials commonly used in the art, such as LiQ, LiF, Yb, etc. The cathode uses materials commonly used in the art, such as metal Al, Ag, or metal mixtures (Ag-doped Mg, Ag-doped Ca, etc.).

[0206] The electrode fabrication methods and the deposition methods of each functional layer in the following embodiments are all conventional methods in the art, such as vacuum thermal evaporation or inkjet printing, and will not be described in detail here. Only some process details and testing methods in the fabrication process are supplemented as follows: Device Example 1 This embodiment provides a blue organic light-emitting device, the fabrication method of which is as follows: An ITO / Ag / ITO substrate is patterned to have a light-emitting area of ​​3mm × 3mm, followed by ultrasonication with water / isopropanol, UV / ozone irradiation, and then drying at 100°C. The ITO / Ag / ITO substrate is then mounted on a substrate support in a vacuum deposition apparatus, and the pressure is adjusted to achieve a vacuum rate of 1 × 10⁻⁶. -7 torr. The following operations are then performed: First, a hole injection layer is formed on the ITO / Ag / ITO layer (anode) formed on the substrate by vacuum deposition of compounds HT01 and PD01 (mass ratio of HT01 to PD01 is 97:3) with a thickness of 10 nm; second, a hole transport layer is formed on the hole injection layer by vacuum deposition of compound HT01 with a thickness of 100 nm; third, a light-emitting auxiliary layer is formed on the hole transport layer by vacuum deposition of compound BP01 with a thickness of 5 nm; fourth, a light-emitting layer is formed on the light-emitting auxiliary layer by vacuum deposition of a mixture of compound B1 and compound BH01 provided by the present invention with a thickness of 20 nm, wherein BH01 is used as the host material and compound B1 is used as the dopant material, and the mass ratio of compound BH01 to compound B1 is 98:2; finally, a hole blocking layer is formed on the light-emitting layer by vacuum deposition of compound HB01 with a thickness of 5 nm. The process involves several steps: First, an electron transport layer is formed by vacuum depositing compounds ET01 and LiQ (in a 1:1 mass ratio) to a hole-blocking layer (30 nm thick). Then, an electron injection layer is formed by vacuum depositing Yb to a thickness of 1 nm on the electron transport layer. Next, a cathode is formed by depositing Mg and Ag (in a 1:9 mass ratio) to a thickness of 15 nm on the electron injection layer. Finally, a capping layer is formed by depositing compound CP01 to a thickness of 50 nm on the cathode. The deposited substrate is then encapsulated. A UV adhesive is applied to the cleaned cover plate using a coating device. The coated cover plate is then moved to the lamination section, and the deposited substrate is placed on top of the cover plate. Finally, the substrate and cover plate are laminated using a bonding device, while simultaneously curing the UV adhesive. This process produces a top-emitting organic light-emitting device (OLED). The device structure is described in [reference needed]. Figure 1 .

[0207] Except for the doped material, the molecular structure formulas of the remaining layers are as follows:

[0208]

[0209] .

[0210] Device Examples 2-30 This embodiment provides a blue organic electroluminescent device, which is prepared by replacing compound B1 in device embodiment 1 with compounds B2 to B30 to form a light-emitting layer. Other preparation steps are the same as in device embodiment 1, and blue organic electroluminescent devices are prepared accordingly.

[0211] Device Comparison Examples 1-4 The method is the same as in Device Example 1, except that compound B1 in Device Example 1 is replaced with compounds D1 to D4 to form the light-emitting layer. Other preparation steps are the same as in Device Example 1, and blue organic electroluminescent devices are prepared respectively.

[0212] Performance evaluation of organic electroluminescent devices The OLED devices described above were tested using standard methods. For this purpose, J = 10 mA / cm² was used. 2 The driving voltage, luminance, electroluminescent current efficiency (in cd / A), and external quantum efficiency (EQE, in percentage) of the organic electroluminescent device were determined at a given current density. The emission spectrum was calculated as a function of luminescence density from the current / voltage / luminescence density characteristic line (IVL characteristic line), which exhibits Lambertian emission characteristics. The lifetime LT was defined as the time after which, when operating at a constant current J, the luminance decreases from the initial luminance L0 to a specific proportion L1; J = 20 mA / cm². 2 The statement L1 = 97% refers to a value of 20 mA / cm². 2 When operating below this threshold, the luminous intensity decreases to 97% of its initial value L0 after time LT. (At J = 20 mA / cm²) 2 The lifetime (LT97) of the organic electroluminescent device was determined at a given current density.

[0213] Table 2 summarizes the data for various OLED devices. The parameters of the device examples and comparative examples are compared to demonstrate the performance data of the various OLED devices.

[0214] The testing instruments and methods used to perform performance testing on the OLED devices of the above embodiments and comparative examples are as follows: Quantum efficiency (CE) (cd / A), chromaticity coordinates (CIEy), and emission half-width were measured using a PhotoResearch PR-655 spectral scanner. Current density and turn-on voltage: tested using a Keithley 2400 digital source meter; The blue index is obtained by dividing the quantum efficiency CE (cd / A) by the color coordinate (CIEy); In Table 2, LT95 refers to the blue OLED device fabricated at J=20mA / cm. 2When operating below the threshold, the luminous intensity drops to 95% of its initial value L0 after time LT95. EQE and LT95 are normalized to 100% based on the performance of device embodiment 9.

[0215] Table 2 Performance test results of blue light devices

[0216] Compared to Comparative Example 4, in Comparative Example 12, the introduction of heteroatoms alters the molecular charge distribution, affecting f and increasing the radiative transition rate, thereby improving EQE and device lifetime. Compared to Comparative Examples 1 and 3, the addition of a heteroatom-containing aromatic ring silicon-based fragments at the boron para-site accelerates the radiative transition rate, improving exciton utilization and EQE. In Comparative Example 2, the boron para-site of the doped material also contains aromatic amine fragments. The N atoms in these fragments further enhance the oscillator strength. Excessive oscillator strength leads to a further increase in exciton density, exacerbating exciton-exciton annihilation (TTA) and exciton-polaron quenching (TPQ), resulting in a significant decrease in EQE and LT.

[0217] The above description is merely a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in the present invention should be included within the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be determined by the scope of the claims.

Claims

1. A boron-nitrogen polycyclic compound containing heteroatom silicon-based segments, characterized in that, The general structural formula of the boron-nitrogen polycyclic compound is shown in Formula I: I； In this context, each occurrence of R1 independently represents a substituted or unsubstituted alkyl group with C1-C10 carbon atoms, a substituted or unsubstituted aryl group with C6-C30 carbon atoms, or a substituted or unsubstituted heteroaryl group with C5-C30 carbon atoms. Any one of them; Each time R2 appears, it independently represents any one of the following: a substituted or unsubstituted alkyl group with C1 to C10 carbon atoms, a substituted or unsubstituted aryl group with C6 to C30 carbon atoms, or a substituted or unsubstituted heteroaryl group with C5 to C30 carbon atoms. Each time R appears, it independently represents any one of the following: a substituted or unsubstituted aryl group with C6 to C20 carbon atoms, or a substituted or unsubstituted heteroaryl group with C5 to C20 carbon atoms. Two or more R1 and R2 can connect with each other to form a fat ring; R6 and R7 represent hydrogen; m and n each independently represent 0, 1, 2, 3 or 4; X represents O or S; Each time Y appears, it independently represents any one of the following: a substituted or unsubstituted aryl group with C6 to C30 carbon atoms, or a substituted or unsubstituted heteroaryl group with C5 to C30 carbon atoms, and at least one Y represents a substituted or unsubstituted heteroaryl group with C5 to C30 carbon atoms. When R1, R2, and R contain substituents, the substituents are selected from any one of alkyl groups having C1 to C10 carbon atoms, cycloalkyl groups having C3 to C30 carbon atoms, and aryl groups having C6 to C20 carbon atoms; two or more of the substituents can be linked together to form an aliphatic ring; When Y contains a substituent, the substituent is selected from any one of alkyl groups having C1 to C10 carbon atoms, cycloalkyl groups having C3 to C30 carbon atoms, and aryl groups having C6 to C20 carbon atoms; two or more of the substituents may be linked together to form an aliphatic ring; In Formula I, any hydrogen atom can be substituted with deuterium.

2. The boron-nitrogen polycyclic compound according to claim 1, characterized in that, X represents O.

3. The boron-nitrogen polycyclic compound according to claim 1, characterized in that, Each time R appears, it independently represents any one of substituted or unsubstituted phenyl or substituted or unsubstituted biphenyl. Each time R1 appears, it independently represents any one of the following: a substituted or unsubstituted alkyl group with C1 to C10 carbon atoms, or a substituted or unsubstituted aryl group with C6 to C30 carbon atoms. Each time R2 appears, it independently represents any one of the following: a substituted or unsubstituted alkyl group with C1 to C10 carbon atoms, or a substituted or unsubstituted aryl group with C6 to C30 carbon atoms.

4. A boron-nitrogen polycyclic compound containing heteroatom silicon-based segments, characterized in that, The general structural formula of the boron-nitrogen polycyclic compound is shown in Formula I: I； Each time R appears, it independently represents a substituted or unsubstituted triphenyl; R1, R2, R, m, n, X, Y, and the substituents of R1, R2, R, Y as defined in claim 1.

5. The boron-nitrogen polycyclic compound according to claim 1 or 4, characterized in that, Each occurrence of Y independently represents one of the following structures: 、 、 、 、 、 、 、 、 、 、 、 、 、 、 。 6. The boron-nitrogen polycyclic compound according to claim 1 or 4, characterized in that, The general structural formula of the boron-nitrogen polycyclic compound is shown in one of the following: I-1、 I-2、 I-3、 I-4、 I-5、 I-6、 I-7、 I-8; R3 represents one of the following structures: 、 、 、 、 、 、 、 、 、 、 、 、 、 、 、 、 、 、 、 、 、 、 、 、 、 、 、 、 、 、 、 、 、 、 、 、 、 、 ； R4 represents one of the following structures: 、 、 、 、 、 、 、 、 、 、 、 ； Any one of the hydrogen atoms in the above groups can be replaced by deuterium; Y1 and Y2 independently represent substituted or unsubstituted aryl groups with C6 to C20 carbon atoms; Y3 represents a substituted or unsubstituted heteroaryl group with a carbon number of C5 to C20.

7. The boron-nitrogen polycyclic compound according to claim 5, characterized in that, Y1 and Y2 each independently represent one of the following structures: 、 、 ； Y3 represents one of the following structures: 、 、 、 、 、 、 、 、 、 、 、 。 8. The boron-nitrogen polycyclic compound according to claim 1 or 4, characterized in that, Each occurrence of R1 is represented independently. , , , Any one of them; Each time R5 appears, it independently represents hydrogen; R6 and R7 represent hydrogen; Two adjacent R1s can be connected to each other to form a ring structure; p represents 0, 1, or 2; R2 represents each independently. , , , Any one of them; Each time R8 appears, it independently represents hydrogen; Two adjacent R2s can be connected to each other to form a ring structure; q represents 0, 1, and 2.

9. A boron-nitrogen polycyclic compound containing heteroatom silicon-based segments, characterized in that, The boron-nitrogen polycyclic compounds are selected from the structures shown below: 。 10. An organic electroluminescent device, characterized in that, It includes an anode, a hole transport region, a light-emitting layer, an electron transport region, and a cathode sequentially disposed on a substrate; wherein the light-emitting layer comprises one or more boron-nitrogen polycyclic compounds as described in any one of claims 1-9.

11. The organic electroluminescent device according to claim 10, characterized in that, The light-emitting layer comprises a host material and a dopant material, wherein the dopant material comprises one or more boron-nitrogen polycyclic compounds as described in any one of claims 1-9.

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