Compound, preparation method thereof and electronic device

Abstract

The invention discloses a compound, a preparation method thereof and an electronic device, the molecular structure general formula of the compound is # imgabs0 #, R is selected from one of the following structures: # imgabs1 #, and X1-X4 are respectively and independently selected from one of methyl, trifluoromethyl and tert-butyl. According to the compound provided by the invention, the electron pushing and pulling capability in the compound is adjusted by changing the structures of a donor and an acceptor, so that the purpose of regulating and controlling molecular electron cloud distribution and energy level is achieved, and emitted light with various wavelengths is realized; the compound as a guest material of a luminescent layer has good comprehensive performance when being applied to electroluminescent devices for solution processing and vacuum evaporation.

Description

Technical Field

[0001] The invention relates to the technical field of organic electroluminescent materials, and in particular to a compound and a preparation method thereof and an electronic device. Background Art

[0002] Organic Light Emitting Diode (OLED) is a self-luminous display technology. It is widely used in televisions, smart phones, wearable devices, lighting and other fields due to its advantages such as bright colors, fast response speed, large viewing angle, low driving voltage, energy saving, light weight and flexible display. Among them, thermally activated delayed fluorescence (TADF) materials as the light-emitting layer have become the forefront of research in recent years due to their significant advantage of using precious metal-free organic molecules with an exciton utilization rate of 100%. The notable feature of TADF materials is that the lowest occupied orbital (HOMO) and the highest unoccupied orbital (LUMO) are effectively separated through special molecular design, reducing the energy level difference (ΔE) between the lowest excited singlet state and the triplet state. ST ), so that the singlet exciton is converted to a singlet exciton through the reverse intersystem crossing process at room temperature, and then emits light through the singlet radiative transition. For an ideal TADF material, a fast exciton decay process is essential, which is controlled by both the reverse intersystem crossing rate and the singlet radiative process. The former requires a small ΔE ST , while the latter requires a large oscillator strength (f), however, they show opposite dependence on the orbital overlap integral.

[0003] The traditional design principle of most TADF materials can be simplified to a donor (D)-acceptor (A) or D-π-Α structure with one or more donors or acceptors. For TADF molecules with completely separated molecular orbital distribution, the material donor-acceptor remote charge transfer (LR-CT) excited state can be realized, thereby obtaining a smaller ΔE ST , but such materials also have a small f. The traditional way to solve this problem is to introduce some orbital overlap on the π bridge to achieve hybrid localized excited (LE) states to increase the f value. However, in molecular design, it is necessary to precisely balance the appropriate ratio of LR-CT and LE excited states to achieve a small ΔE ST And larger f is quite difficult.

[0004] Therefore, the prior art still needs to be improved and developed. Summary of the invention

[0005] In view of the above-mentioned deficiencies in the prior art, the object of the present invention is to provide a compound and a preparation method thereof and an electronic device, aiming to solve the problem that it is difficult for existing TADF molecules to have a small ΔE ST and the problem of larger f.

[0006] The technical solution of the present invention is as follows:

[0007] The first aspect of the present invention provides a compound, the molecular structure of the compound is as follows:

[0008] Wherein, R is selected from one of the following structures:

[0009]

[0010] Wherein, X1-X4 are independently selected from one of methyl, trifluoromethyl and tert-butyl.

[0011] Preferably, the compound is one of the following structures:

[0012]

[0013]

[0014]

[0015]

[0016] The second aspect of the present invention provides a method for preparing the above-mentioned compound, the preparation method comprising the following steps:

[0017] The trifluoromethyl-substituted phenol reacts with 2,5-dibromo-1,3-difluorobenzene under the action of cesium carbonate to produce an unclosed ring intermediate;

[0018] The unclosed ring intermediate is mixed with n-butyl lithium, and boron tribromide and N,N-diisopropylethylamine are added in sequence to react to obtain a boron-oxygen fused ring receptor;

[0019] The boron-oxygen fused ring acceptor and the donor R are mixed in a toluene solution, and the compound is obtained by a Buchwald–Hartwig cross-coupling reaction under the action of tri(dibenzylideneacetone)dipalladium, tri-tert-butylphosphine tetrafluoroborate, and potassium tert-butoxide;

[0020] The above-mentioned synthetic route is as follows:

[0021]

[0022] According to a third aspect of the present invention, an electronic device is provided, wherein the electronic device comprises the above-mentioned compound.

[0023] Preferably, the electronic device is an organic electroluminescent device, and the organic electroluminescent device comprises a light-emitting layer, and the light-emitting layer comprises the above-mentioned compound.

[0024] Preferably, the electronic device also includes an organic light-emitting cell, an organic field effect transistor, an organic light-emitting field effect transistor, an organic laser, an organic sensor, an organic photovoltaic cell, and an organic spin electronic device, but is not limited thereto.

[0025] Preferably, the electronic device is an organic electroluminescent device, which comprises a functional layer, wherein the functional layer is composed of 0.1-99.9% by mass of the above-mentioned compound and 0.1-99.9% by mass of an organic functional material.

[0026] Preferably, the organic functional material is one of hole injection material, hole transport material, hole blocking material, electron injection material, electron transport material, electron blocking material, exciton blocking material, fluorescent material, phosphorescent material, host material, and organic dye.

[0027] Beneficial effects:

[0028] The present invention provides a compound and a preparation method thereof and an electronic device. The thermally activated delayed fluorescent molecule based on a boron-oxygen multi-resonance electron acceptor provided by the present invention has a short-range multi-resonance charge transfer excited state component in its excited state, so it usually has a high oscillator strength (f), which is conducive to achieving rapid radiation transition and high luminescence efficiency.

[0029] The compound provided by the present invention adjusts the ability of pushing and pulling electrons inside the compound by changing the structure of the donor and the acceptor, thereby achieving the purpose of regulating the distribution and energy level of the molecular electron cloud to realize emission of light of multiple wavelengths. The compound is used as a guest material of the light-emitting layer in solution-processed and vacuum-evaporated electroluminescent devices and has good comprehensive performance.

[0030] The rigid steric donor of the compound of the present invention is connected to the trifluoromethyl-substituted boron oxygen acceptor by a single bond to achieve a certain molecular distortion, thereby better separating the highest occupied orbital (HOMO) and the lowest unoccupied orbital (LUMO). The smaller overlap of HOMO and LUMO can reduce the energy level difference (ΔE) between the singlet state and the triplet state. ST ), ΔE is small enough ST Thermally activated delayed fluorescence properties can be achieved. And a smaller ΔE ST The efficiency of the reverse intersystem crossing process is made higher, so OLED devices using this type of compound can achieve high luminous efficiency while effectively reducing the lighting voltage.

[0031] The compound of the present invention improves the molecular rigidity by introducing a rigid donor, which can minimize the non-radiative transition process in the molecular excited state, and high molecular rigidity is crucial to improving the quantum yield. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] Figure 1 The UV-visible absorption and fluorescence emission spectra of the compound prepared in Example 1 of the present invention in a diluted toluene solution are shown.

[0033] Figure 2 The UV-visible absorption and fluorescence emission spectra of the compound prepared in Example 2 of the present invention in a diluted toluene solution are shown.

[0034] Figure 3 The UV-visible absorption and fluorescence emission spectra of the compound prepared in Example 3 of the present invention in a diluted toluene solution are shown.

[0035] Figure 4 This is a structural diagram of an organic electroluminescent device prepared according to an application example of the present invention.

[0036] Figure 5 This is a molecular structure diagram of the functional layer of an organic electroluminescent device prepared in an application example of the present invention.

[0037] Figure 6 This is an electroluminescence spectrum diagram of the organic electroluminescent device prepared in the application example of the present invention.

[0038] Figure 7 This is a graph showing the maximum external quantum efficiency of an organic electroluminescent device prepared in an application example of the present invention as a function of brightness. DETAILED DESCRIPTION

[0039] The present invention provides a compound and a preparation method thereof and an electronic device. To make the purpose, technical solution and effect of the present invention clearer and more specific, the present invention is further described in detail below. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention.

[0040] The structural formulas of compounds (a), (b), (c), (d), (e) and (f) prepared in the following examples of the present invention are as follows:

[0041]

[0042] Example 1

[0043] The preparation of compound (a) comprises the following steps:

[0044] (1) Preparation of compound 2: Take a 250mL two-necked flask, add m-trifluoromethylphenol (6.48g, 40mmol), 2,5-dibromo-1,3-difluorobenzene (5.44g, 20mmol), potassium carbonate (5.52g, 40mmol) and 60mL of N,N-dimethylformamide under argon protection, react at 120°C for 8 hours, cool to room temperature, filter through diatomaceous earth, and extract three times with DCM and water. The combined organic phase is dried over anhydrous Na2SO4 and concentrated under reduced pressure. The crude product is purified by silica gel column chromatography using DCM / PE (v / v=1 / 10) as eluent to obtain 10.01g of white solid with a yield of 90%. The synthetic process of the above reaction is as follows:

[0045]

[0046] 1 H NMR (500MHz, CDCl3) δ [ppm]: 7.52 (t, J = 8.0 Hz, 2H), 7.46 (d, J = 7.8 Hz, 2H), 7.31 (s, 2H), 7.20 (dd, J = 8.1, 2.0 Hz, 2H), 6.89 (s, 2H).

[0047] (2) Preparation of compound 3: Take a 200 mL pressure bottle, add compound 2 (5.56 g, 10 mmol) and 60 mL of o-dichlorobenzene under argon protection, and stir for 0.3 h. Slowly add a solution of n-butyl lithium in pentane (4.4 mL, 2.50 M, 11 mmol) at 0 ° C, stir for 0.5 h, and then transfer to room temperature for 2 h. After pentane and other low-boiling point molecules are removed in a vacuum, boron tribromide (1.2 mL, 12 mmol) is added at -40 ° C. After the reaction mixture is stirred at room temperature for 1 h, N, N-diisopropylethylamine (1.94 g, 15 mmol) is added at 0 ° C, and then the reaction mixture is transferred to room temperature and heated to 150 ° C and stirred for 5 h. After cooling to room temperature, it is filtered off through diatomaceous earth and extracted three times with DCM and water. The combined organic phase is dried over anhydrous Na2SO4 and concentrated under reduced pressure. The crude product was purified by silica gel column chromatography using DCM / PE (v / v=1 / 10) as eluent to obtain 1.46 g of a white solid with a yield of 30%. The synthetic process of the above reaction is as follows:

[0048]

[0049] 1 H NMR (500MHz, CDCl3) δ [ppm]: 8.75 (d, J = 8.0 Hz, 2H), 7.84 (s, 2H), 7.66 (d, J = 8.0 Hz, 2H), 7.50 (s, 2H).

[0050] (3) Preparation of compound (a): Take a 200 mL two-necked flask, add compound 3 (1.02 g, 2.1 mmol), compound 4 (0.99 g, 2 mmol), tri(dibenzylideneacetone)dipalladium (0.18 g, 0.2 mmol), tri-tert-butylphosphine tetrafluoroborate (0.12 g, 0.4 mmol), sodium tert-butoxide (0.24 g, 2.5 mmol) and 60 mL of toluene under argon protection, react at 110° C. for 3 h, cool to room temperature, filter through diatomaceous earth, and extract three times with DCM and water. The combined organic phase is dried over anhydrous Na2SO4 and concentrated under reduced pressure. The crude product is purified by silica gel column chromatography using DCM / PE (v / v=1 / 10) as eluent to obtain 0.81 g of a yellow solid with a yield of 45%. The synthetic process of the above reaction is as follows:

[0051]

[0052] 1 H NMR(500MHz, CDCl3)δ[ppm]:8.84(d,J=8.1Hz,2H),7.83(s,2H),7.72–7.62(m,15H),7.36(d,J=8.2Hz,1H),7.32(d,J=8.1Hz,1H),7.22(dd,J=1 4.4, 7.0Hz, 2H), 7.06 (t, J = 7.6Hz, 1H), 6.82 (dt, J = 11.5, 7.7Hz, 2H), 6.57 (t, J = 7.6Hz, 1H), 6.31 (d, J = 8.1Hz, 1H), 6.09 (dd, J = 8.0, 5.2Hz, 2H).

[0053] 13 C NMR (126MHz, CDCl3) δ160.30,158.25,147.93,141.77,141.73,141.22,140.81,140.76,137.74, 137.44,137.00,135.76,135.49,135.35,130.04,130.02,129.01,128.39,124.63,124.53,123.5 9,123.46,123.35,122.87,122.72,122.36,122.31,122.29,121.84,120.98,120.13,120.07,119.52,119.49,116.26,116.20,113.75,110.08,109.97,109.83,109.09,105.42,105.23,104.67.

[0054] Example 2

[0055] The preparation of compound (b) comprises the following steps:

[0056] (1) Preparation of compound 2: Take a 250mL two-necked flask, add m-trifluoromethylphenol (3.24g, 20mmol), 2,5-dibromo-1,3-difluorobenzene (5.44g, 20mmol), potassium carbonate (5.52g, 40mmol) and 60mL of N,N-dimethylformamide under argon protection, and react at 90°C for 3 hours. After cooling to room temperature, add phenol (1.88g, 20mmol) under argon protection, and continue to react at 120°C for 8h. After the reaction is completed, cool to room temperature, filter through diatomaceous earth, and extract with DCM and water three times. The combined organic phase is dried over anhydrous Na2SO4 and concentrated under reduced pressure. The crude product is purified by silica gel column chromatography using DCM / PE (v / v=1 / 10) as eluent to obtain 8.3g of white solid with a yield of 85%. The synthetic process of the above reaction is as follows:

[0057]

[0058] 1 H NMR(500MHz, CDCl3)δ[ppm]:7.50(t,J=8.0Hz,1H),7.45–7.39(m,3H),7.29(s,1H),7.22(t,J =7.4Hz, 1H), 7.18 (dd, J = 8.1, 2.0Hz, 1H), 7.07 (d, J = 7.8Hz, 2H), 6.82 (dd, J = 8.7, 2.1Hz, 2H).

[0059] (2) Preparation of compound 3: Take a 200 mL pressure bottle, add compound 2 (4.88 g, 10 mmol) and 60 mL of o-dichlorobenzene under argon protection, and stir for 0.3 h. Slowly add a solution of n-butyl lithium in pentane (4.4 mL, 2.50 M, 11 mmol) at 0 ° C, stir for 0.5 h, and then transfer to room temperature for 2 h. After pentane and other low-boiling point molecules are removed in a vacuum, boron tribromide (1.2 mL, 12 mmol) is added at -40 ° C. After the reaction mixture is stirred at room temperature for 1 h, N, N-diisopropylethylamine (1.94 g, 15 mmol) is added at 0 ° C, and then the reaction mixture is transferred to room temperature and heated to 150 ° C and stirred for 5 h. After cooling to room temperature, filter it through diatomaceous earth and extract it three times with DCM and water. The combined organic phase is dried over anhydrous Na2SO4 and concentrated under reduced pressure. The crude product was purified by silica gel column chromatography using DCM / PE (v / v=1 / 10) as eluent to obtain 1.33 g of a white solid with a yield of 32%. The synthetic process of the above reaction is as follows:

[0060]

[0061] 1 H NMR(500MHz, CDCl3)δ[ppm]:8.61(d,J=8.0Hz,1H),8.48(dd,J=7.7,1.4Hz,1H),7.73–7.69(m,1H),7.68(s,1H),7.5 4(d,J=8.0Hz,1H),7.46(d,J=8.3Hz,1H),7.36(dd,J=10.9,3.8Hz,1H),7.31(d,J=1.3Hz,1H),7.27(d,J=1.3Hz,1H).

[0062] (3) Preparation of compound (b): Take a 200 mL two-necked flask, add compound 3 (0.88 g, 2.1 mmol), compound 4 (0.99 g, 2 mmol), tri(dibenzylideneacetone)dipalladium (0.18 g, 0.2 mmol), tri-tert-butylphosphine tetrafluoroborate (0.12 g, 0.4 mmol), sodium tert-butoxide (0.24 g, 2.5 mmol) and 60 mL of toluene under argon protection, react at 110° C. for 3 h, cool to room temperature, filter through diatomaceous earth, and extract three times with DCM and water. The combined organic phase is dried over anhydrous Na2SO4 and concentrated under reduced pressure. The crude product is purified by silica gel column chromatography using DCM / PE (v / v=1 / 10) as eluent to obtain 0.72 g of a green solid with a yield of 43%. The synthetic process of the above reaction is as follows:

[0063]

[0064] 1 H NMR (500MHz, CDCl3) δ [ppm]: 8.88 (d, J = 8.0Hz, 1H), 8.73 (d, J = 7.7Hz, 1H), 7.77 (dd, J = 12.1, 5.0Hz,2H),7.73–7.60(m,13H),7.56(dd,J=9.5,4.9Hz,2H),7.47(t,J=7.4Hz,1H),7.36(d, J=8.1Hz,1H),7.32(d,J=8.1Hz,1H),7.21(td,J=7.6,4.4Hz,2H),7.06(t,J=7.7Hz,1H),6.8 1(q,J=7.7Hz,2H), 6.58(t,J=7.6Hz,1H), 6.33(d,J=8.1Hz,1H), 6.09(dd,J=7.9,5.8Hz,2H).

[0065] 13 C NMR (126MHz, CDCl3) δ160.79,160.19,158.43,158.19,147.29,141.72,141.35,140.85,140. 82,137.71,137.48,137.19,135.60,135.30,135.04,134.38,130.02,130.00,129.01,128.3 4,124.64,123.50,123.37,123.30,122.77,122.70,122.47,122.37,122.05,120.78,120.15,120.08,119.22,118.88,116.05,113.82,109.95,109.21,108.65,105.26,105.07,104.73.

[0066] Example 3

[0067] The preparation of compound (c) comprises the following steps:

[0068] (1) Preparation of compound 2: Take a 250 mL two-necked flask, add m-trifluoromethylphenol (3.24 g, 20 mmol), 2,5-dibromo-1,3-difluorobenzene (5.44 g, 20 mmol), potassium carbonate (5.52 g, 40 mmol) and 60 mL of N,N-dimethylformamide under argon protection, and react at 90°C for 3 hours. After cooling to room temperature, add p-tert-butylphenol (3.00 g, 20 mmol) under argon protection, and continue to react at 120°C for 8 hours. After the reaction is completed, cool to room temperature, filter through diatomaceous earth, and extract with DCM and water three times. The combined organic phase is dried over anhydrous Na2SO4 and concentrated under reduced pressure. The crude product is purified by silica gel column chromatography using DCM / PE (v / v=1 / 10) as eluent to obtain 9.5 g of white solid with a yield of 87%. The synthetic process of the above reaction is as follows:

[0069]

[0070] 1 H NMR(500MHz, CDCl3)δ[ppm]:7.50(t,J=8.0Hz,1H),7.46–7.39(m,3H),7.29(s, 1H), 7.18 (dd, J=8.2, 2.1Hz, 1H), 7.02–6.97 (m, 2H), 6.81 (s, 2H), 1.35 (s, 9H).

[0071] (2) Preparation of compound 3: Take a 200 mL pressure bottle, add compound 2 (5.44 g, 10 mmol) and 60 mL of o-dichlorobenzene under argon protection, and stir for 0.3 h. Slowly add a solution of n-butyl lithium in pentane (4.4 mL, 2.50 M, 11 mmol) at 0 ° C, stir for 0.5 h, and then transfer to room temperature for 2 h. After pentane and other low-boiling point molecules are removed in a vacuum, boron tribromide (1.2 mL, 12 mmol) is added at -40 ° C. After the reaction mixture is stirred at room temperature for 1 h, N, N-diisopropylethylamine (1.94 g, 15 mmol) is added at 0 ° C, and then the reaction mixture is transferred to room temperature and heated to 150 ° C and stirred for 5 h. After cooling to room temperature, filter it through diatomaceous earth and extract it three times with DCM and water. The combined organic phase is dried over anhydrous Na2SO4 and concentrated under reduced pressure. The crude product was purified by silica gel column chromatography using DCM / PE (v / v=1 / 10) as eluent to obtain 1.66 g of a white solid with a yield of 33%. The synthetic process of the above reaction is as follows:

[0072]

[0073] 1 H NMR (500MHz, CDCl3) δ [ppm]: 8.67 (d, J = 8.0Hz, 1H), 8.53 (d, J = 2.3Hz, 1H), 7.81 (dd, J = 8.8, 2.4Hz, 1H), 7.73 (s ,1H),7.61(d,J=8.0Hz,1H),7.46(d,J=8.8Hz,1H),7.36(d,J=1.3Hz,1H),7.30(d,J=1.3Hz,1H),1.48(s,9H).

[0074] (3) Preparation of compound (c): Take a 200 mL two-necked flask, add compound 3 (0.99 g, 2.1 mmol), compound 4 (0.99 g, 2 mmol), tri(dibenzylideneacetone)dipalladium (0.18 g, 0.2 mmol), tri-tert-butylphosphine tetrafluoroborate (0.12 g, 0.4 mmol), sodium tert-butoxide (0.24 g, 2.5 mmol) and 60 mL of toluene under argon protection, react at 110° C. for 3 h, cool to room temperature, filter through diatomaceous earth, and extract three times with DCM and water. The combined organic phase is dried over anhydrous Na2SO4 and concentrated under reduced pressure. The crude product is purified by silica gel column chromatography using DCM / PE (v / v=1 / 10) as eluent to obtain 0.80 g of a green solid with a yield of 45%. The synthetic process of the above reaction is as follows:

[0075]

[0076] 1H NMR (500MHz, CDCl3) δ [ppm]: 8.86 (d, J = 8.0 Hz, 1H), 8.71 ( d, J = 2.4 Hz, 1H), 7.84 ( dd, J = 8.8, 2.4 Hz, 1H ),7.79(s,1H),7.65(dddd,J=19.7,16.9,9.2,1.8Hz,13H),7.53(d,J=1.5Hz,1H),7.51(d,J=8.8Hz,1 H),7.36(d,J=8.1Hz,1H),7.31(d,J=8.1Hz,1H),7.23–7.16(m,2H),7.06(d,J=7.6Hz,1H),6.81(td,J =8.0,0.8Hz,2H),6.61–6.52(m,1H),6.32(d,J=8.1Hz,1H),6.09(dd,J=8.0,5.3Hz,2H),1.51(s,9H).

[0077] 13 C NMR (126MHz, CDCl3) δ160.22,158.97,158.51,158.17,149.30,147.09,145.93,141.71,141.36,140.86,140.83,1 37.70,137.48,137.22,135.52,135.20,134.93,134.67,132.35,130.02,130.00,129.95,129.02,128.33,125.30, 124.67,123.48,123.35,123.29,123.25,122.75,122.69,122.50,122.39,122.08,121.39,120.73,120.16,120.07,119.36,119.33,118.41,116.07,116.04,113.89,109.95,109.21,108.50,105.21,105.03,104.73,34.69,31.62.

[0078] Example 4

[0079] The preparation of compound (d) comprises the following steps:

[0080] (1) The preparation of compound 3 is the same as in Example 1, and the synthetic route is as follows:

[0081]

[0082] (2) Preparation of compound (d): Take a 200 mL two-necked flask, add compound 3 (0.99 g, 2.1 mmol), compound 4 (0.65 g, 2 mmol), tri(dibenzylideneacetone)dipalladium (0.18 g, 0.2 mmol), tri-tert-butylphosphine tetrafluoroborate (0.12 g, 0.4 mmol), sodium tert-butoxide (0.24 g, 2.5 mmol) and 60 mL of toluene under argon protection, react at 110° C. for 3 h, cool to room temperature, filter through diatomaceous earth, and extract three times with DCM and water. The combined organic phase is dried over anhydrous Na2SO4 and concentrated under reduced pressure. The crude product is purified by silica gel column chromatography using DCM / PE (v / v=1 / 10) as eluent to obtain 0.45 g of a green solid with a yield of 31%. The above synthetic route is as follows:

[0083]

[0084] HRMS(ESI)m / z calcd for C 44 H 23 BF6N2O2[M+H] + 737.1830, found737.1822.

[0086] Example 5

[0087] The preparation of compound (e) comprises the following steps:

[0088] (1) The preparation of compound 3 is the same as in Example 1, and the synthetic route is as follows:

[0089]

[0090] (2) Preparation of compound (e): Take a 200 mL two-necked flask, add compound 3 (0.99 g, 2.1 mmol), compound 4 (0.55 g, 2 mmol), tri(dibenzylideneacetone)dipalladium (0.18 g, 0.2 mmol), tri-tert-butylphosphine tetrafluoroborate (0.12 g, 0.4 mmol), sodium tert-butoxide (0.24 g, 2.5 mmol) and 60 mL of toluene under argon protection, react at 110° C. for 3 h, cool to room temperature, filter through diatomaceous earth, and extract three times with DCM and water. The combined organic phase is dried over anhydrous Na2SO4 and concentrated under reduced pressure. The crude product is purified by silica gel column chromatography using DCM / PE (v / v=1 / 10) as eluent to obtain 0.57 g of a green solid with a yield of 42%. The above synthetic route is as follows:

[0091]

[0092] HRMS(ESI)m / z calcd for C 38 H 18 BF6NO2S[M+H] + 678.1128, found 678.1137.

[0094] Example 6

[0095] The preparation of compound (f) comprises the following steps:

[0096] (1) The preparation of compound 3 is the same as in Example 1, and the synthetic route is as follows:

[0097]

[0098] (3) Preparation of compound (f): Take a 200 mL two-necked flask, add compound 3 (0.99 g, 2.1 mmol), compound 4 (0.51 g, 2 mmol), tri(dibenzylideneacetone)dipalladium (0.18 g, 0.2 mmol), tri-tert-butylphosphine tetrafluoroborate (0.12 g, 0.4 mmol), sodium tert-butoxide (0.24 g, 2.5 mmol) and 60 mL of toluene under argon protection, react at 110° C. for 3 h, cool to room temperature, filter through diatomaceous earth, and extract three times with DCM and water. The combined organic phase is dried over anhydrous Na2SO4 and concentrated under reduced pressure. The crude product is purified by silica gel column chromatography using DCM / PE (v / v=1 / 10) as eluent to obtain 0.53 g of a green solid with a yield of 40%. The above synthetic route is as follows:

[0099]

[0100] HRMS(ESI)m / z calcd for C 38 H 18 BF6NO3[M+H] + 662.1357, found 662.1342.

[0102] The photophysical properties and electroluminescence performance of the compounds prepared in Examples 1-3 were tested.

[0103] Figure 1-3 They are respectively the UV-visible absorption and fluorescence emission spectra of the compounds prepared in Examples 1-3 in diluted toluene solution. It can be seen from the UV-visible absorption spectra that the tested compounds all have two characteristic absorption bands, which are 320nm and 380nm respectively. From the fluorescence emission spectra, it can be seen that the maximum emission wavelengths of the three compounds are 540nm, 517nm and 505nm respectively, and are broad peaks without fine structures.

[0104] Application Example 1

[0105] The compound prepared in Example 1 was used as a light-emitting layer in an organic electroluminescent device, and the organic electroluminescent device was prepared by vacuum evaporation.

[0106] Application Example 2

[0107] The compound prepared in Example 2 was used as a light-emitting layer in an organic electroluminescent device, and the organic electroluminescent device was prepared by vacuum evaporation.

[0108] Application Example 3

[0109] The compound prepared in Example 3 was used as a light-emitting layer in an organic electroluminescent device, and the organic electroluminescent device was prepared by vacuum evaporation.

[0110] The structure of the organic electroluminescent device prepared in the above application example is as follows Figure 4 As shown, the specific structure is ITO / HAT-CN / TAPC / TCTA / mCBP / DMIC-TRZ: Example / ANT-BIZ / Liq / Al, the compound is doped in the main material DMIC-TRZ at a ratio of 10%, and the specific functional layer molecular formula is as follows Figure 5 shown.

[0111] Figure 6 The electroluminescence spectra of the organic electroluminescent devices prepared in Application Examples 1-3 show that the maximum emission wavelengths of compound (a), compound (b) and compound (c) in the organic electroluminescent devices are 540 nm, 514 nm and 507 nm, respectively, which are basically consistent with the emission in the solution.

[0112] Figure 7 The maximum external quantum efficiency of the organic electroluminescent device prepared in Application Examples 1-3 varies with brightness. It can be seen from the figure that the maximum external quantum efficiency of compound (a), compound (b) and compound (c) in the electroluminescent device is 38.6%, 38.1% and 37.2% respectively. 2 Under the conditions of , the maximum external quantum efficiencies are 36.8%, 36.1% and 34.8% respectively. The specific device efficiencies are shown in Table 1.

[0113] Table 1

[0114]

[0115] It should be understood that the application of the present invention is not limited to the above examples. For ordinary technicians in this field, improvements or changes can be made based on the above description. All these improvements and changes should fall within the scope of protection of the claims attached to the present invention.

Claims

1. A compound, characterized in that The molecular structure of the compound is as follows: Wherein, R is selected from one of the following structures: Wherein, X1-X4 are independently selected from one of methyl, trifluoromethyl and tert-butyl.

2. The compound according to claim 1, characterized in that The compound is one of the following structures:

3. A method for preparing the compound according to any one of claims 1 to 2, characterized in that: The preparation method comprises the following steps: The trifluoromethyl-substituted phenol reacts with 2,5-dibromo-1,3-difluorobenzene under the action of cesium carbonate to produce an unclosed ring intermediate; The unclosed ring intermediate is mixed with n-butyl lithium, and boron tribromide and N,N-diisopropylethylamine are added in sequence to react to obtain a boron-oxygen fused ring receptor; The boron-oxygen fused ring acceptor and the donor R are mixed in a toluene solution, and the compound is obtained by a Buchwald–Hartwig cross-coupling reaction under the action of tri(dibenzylideneacetone)dipalladium, tri-tert-butylphosphine tetrafluoroborate, and potassium tert-butoxide; The above-mentioned synthetic route is as follows:

4. An electronic device, characterized in that: The electronic device comprises the compound according to any one of claims 1-2.

5. The electronic device according to claim 4, characterized in that: The electronic device is an organic electroluminescent device, which comprises a light-emitting layer, and the light-emitting layer comprises the compound according to any one of claims 1 to 2.

6. The electronic device according to claim 4, characterized in that: The electronic device is an organic electroluminescent device, which comprises a functional layer, wherein the functional layer is composed of 0.1-99.9% by mass of the compound according to any one of claims 1 to 2 and 0.1-99.9% by mass of an organic functional material.

7. The electronic device according to claim 6, characterized in that: The organic functional material is one of hole injection material, hole transport material, hole blocking material, electron injection material, electron transport material, electron blocking material, exciton blocking material, fluorescent material, phosphorescent material, host material and organic dye.

Images