Compound, preparation method thereof and electronic device

Abstract

The invention discloses a compound and a preparation method thereof and an electronic device, the molecular structure general formula of the compound is shown in the specification, R is selected from one of the following structures, X1-X2 are respectively and independently selected from one of oxygen atoms, sulfur atoms, selenium atoms and nitrogen atoms, and X is a positive integer. X < 3 > to X < 4 > are respectively and independently selected from one of the following structures; and X < 5 > to X < 6 > are respectively and independently selected from any one of alkyl groups. 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 key physical properties such as emission wavelength, radiative transition rate (kr) and backlash crossing rate (kRISC) of a material are systematically regulated and controlled. The compound as a guest material of a luminescent layer has good comprehensive performance when being applied to organic electroluminescent devices for solution processing and vacuum evaporation.

Description

Technical Field

[0001] This invention relates to the field of organic electroluminescent materials technology, and more particularly to a compound, its preparation method, and electronic devices. Background Technology

[0002] Organic light-emitting diodes (OLEDs) have become a hot research topic for researchers worldwide due to their numerous advantages, including light weight, low power consumption, fast response speed, high contrast, wide viewing angle, and flexibility. As a third-generation OLED material, thermally activated delayed fluorescence (TADF) achieves a smaller singlet-triplet energy level difference (ΔE) by separating the highest occupied molecular orbital (HOMO) and the lowest unoccupied molecular orbital (LUMO). ST Using ambient thermal energy, triplet excitons are converted back to singlet states via reverse inter-system crossing (RISC), and finally, TADF is achieved through an S1→S0 radiative transition. This process results in a theoretical internal quantum efficiency of 100% for this type of material, breaking the limits of traditional fluorescent materials and even rivaling traditional phosphorescent materials. In addition, TADF materials possess advantages such as low cost, high purity, and high structural precision, attracting widespread attention from researchers and industry both domestically and internationally in recent years. TADF materials are mainly designed using two strategies: donor-acceptor and multiple resonance (MR) types. The reverse inter-system crossing rate (k0) of donor-acceptor TADF materials is... RISC The first type is faster, but cannot meet the requirements for high color purity; while the MR type has better color purity, but k RISC The process is relatively slow, resulting in a significant efficiency roll-off. Therefore, existing TADF materials struggle to simultaneously possess both high luminescent quantum yield (PLQY) and fast radiative transition rate (kJ / kF). r ) and k RISC Furthermore, it exhibits narrow-band emission characteristics. To address this issue, superfluorescent devices have emerged as a novel type of electroluminescent structure. By utilizing a TADF sensitizer to rapidly convert triplet excitons into singlet excitons, and then transferring energy to narrow-band emitting MR guest molecules via fluorescence resonance energy transfer (FRET), high-efficiency, low-roll-off, and high-color-purity luminescence effects are achieved.

[0003] However, the requirements for TADF sensitizers are quite stringent. TADF sensitizers not only need to possess rapid kJ / kJ / twitch detection, but also...RISC Furthermore, the emission spectrum of the sensitizer must have good overlap with the absorption spectrum of the MR guest to ensure effective FRET. In addition, the sensitizer must possess rapid kJ / kJ / g. r To improve the energy transfer rate. However, currently reported TADF materials struggle to simultaneously achieve rapid k-phase transfer. RISC With k r This limits the development of sensitizers for MR guests, especially for narrow-band red MR guests.

[0004] Therefore, existing technologies still need to be improved and developed. Summary of the Invention

[0005] In view of the shortcomings of the prior art, the purpose of this invention is to provide a compound, its preparation method, and an electronic device thereof. The aim is to design and synthesize a class of high-performance red light sensitizers through molecular design, and to match the sensitizers with narrow-band red light-emitting guest molecules to construct a superfluorescent system. This achieves high device efficiency, high stability, and low device efficiency roll-off, thereby solving the problem that existing red-light TADF molecules cannot simultaneously possess rapid k-wave emission. RISC With k r Technical issues.

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

[0007] In a first aspect, the present invention provides a compound having the following general molecular structural formula:

[0008]

[0009] Wherein, R is selected from one of the following structures:

[0010]

[0011] Among them, X1-X2 are each independently selected from one of the following: oxygen atom, sulfur atom, selenium atom, and nitrogen atom; X3-X4 are each independently selected from one of the following structures:

[0012]

[0013] X5-X6 are each independently selected from any one of the alkyl groups. Preferably, the compound has one of the following structures:

[0014]

[0015]

[0016]

[0017]

[0018]

[0019]

[0020]

[0021] A second aspect of the present invention provides a method for preparing the above-described compound, wherein the preparation method comprises the following steps:

[0022] Trifluoromethylphenol was reacted with 2,5-dibromo-1,3-difluorobenzene in the presence of cesium carbonate to give an unclosed intermediate.

[0023] The unclosed intermediate was mixed with n-butyllithium, and boron tribromide and N,N-diisopropylethylamine were added sequentially to react and obtain a boron-oxygen fused ring acceptor.

[0024] The boron-oxygen fused ring acceptor and donor R were mixed in a toluene solution, and the compound was obtained by a Buchwald-Hartwig cross-coupling reaction in the presence of tris(dibenzylacetone)dipalladium, tri-tert-butylphosphine tetrafluoroborate and sodium tert-butoxide.

[0025] The above synthetic route is as follows:

[0026]

[0027] Preferably, the nucleophilic reaction is carried out at a temperature of 120 to 150°C (e.g., 120°C, 130°C, 140°C, 150°C, etc., and other specific values ​​within the above range are also acceptable and will not be listed here). The reaction time is 8 to 24 hours (e.g., 8 hours, 10 hours, 12 hours, 15 hours, 18 hours, 24 hours, etc., and other specific values ​​within the above range are also acceptable and will not be listed here).

[0028] Preferably, the temperature of the Buchwald-Hartwig cross-coupling reaction is 110 to 130°C (e.g., 110°C, 120°C, 130°C, etc., other specific values ​​within the above range can be selected, and will not be listed here). The time is 1 to 3 hours (e.g., 1 hour, 2 hours, 3 hours, etc., other specific values ​​within the above range can be selected, and will not be listed here).

[0029] A third aspect of the present invention provides an electronic device comprising the above-described compound.

[0030] Preferably, the electronic device is an organic electroluminescent device, which includes a light-emitting layer comprising the aforementioned compound.

[0031] More preferably, the light-emitting layer further includes a host material, with the compound serving as the guest material. The mass ratio of the host material to the guest material is 5 to 30:1, such as 5:1, 10:1, 15:1, 20:1, 25:1, 30:1, etc. Other specific values ​​within the above range can be selected, and will not be listed here.

[0032] Preferably, the electronic device also includes organic light-emitting cells, organic field-effect transistors, organic light-emitting field-effect transistors, organic lasers, organic sensors, organic photovoltaic cells, organic spintronic devices, etc., but is not limited thereto.

[0033] Preferably, the electronic device is an organic electroluminescent device, which includes a functional layer composed of the above-mentioned compound at a mass percentage of 0.1-99.9% and an organic functional material at a mass percentage of 0.1-99.9%.

[0034] Preferably, the organic functional material is one of the following: hole injection material, hole transport material, hole blocking material, electron injection material, electron transport material, electron blocking material, exciton blocking material, fluorescent luminescent material, phosphorescent luminescent material, host material, and organic dye.

[0035] Preferably, the electronic device is a superfluorescent device, which includes a light-emitting layer comprising a host material, a guest material, and a sensitizer, wherein the sensitizer is a compound described in this invention.

[0036] Preferably, the mass ratio of the guest material to the host material is 0.5 to 5:100, such as 0.5:100, 1:100, 2:100, 3:100, 4:100, 5:100, etc. Other specific values ​​within the above range can be selected and will not be listed here. The mass ratio of the sensitizer to the host material is 5 to 30:100, such as 5:100, 10:100, 15:100, 20:100, 25:100, 30:100, etc. Other specific values ​​within the above range can be selected and will not be listed here.

[0037] Beneficial effects:

[0038] This invention provides a compound, its preparation method, and an electronic device thereof. The compound is a thermally activated delayed fluorescence molecule based on a boron-oxygen multiple resonance electron acceptor. Its excited state contains a short-range multiple resonance charge transfer excited state component, thus exhibiting a high oscillator strength (f), which is beneficial for simultaneously achieving a fast radiative transition rate and a reverse gap crossover rate.

[0039] The compound provided by this invention modulates the electron-pulling ability within the compound by altering the structures of the donor and acceptor, thereby controlling the distribution of the molecular electron cloud and energy levels to achieve emission in the red light region (wavelength range). As a guest material for the luminescent layer, this compound exhibits excellent overall performance in organic electroluminescent devices fabricated through solution processing or vacuum evaporation. As a luminescent material, its devices exhibit high stability, high efficiency, and low efficiency roll-off. Furthermore, as a sensitizer in superfluorescent devices, it can match narrow-band red-light-emitting guest molecules, resulting in devices with narrow-band emission, high stability, high efficiency, and low efficiency roll-off.

[0040] The compounds provided by this invention achieve efficient separation of the highest occupied molecular orbital (HOMO) and lowest unoccupied molecular orbital (LUMO) through a moderately twisted molecular spatial configuration formed by a rigid donor and a trifluoromethyl-substituted boron-oxygen acceptor via a single bond. The smaller overlap between the HOMO and LUMO helps to reduce the energy level difference (ΔE) between the singlet and triplet states. ST This achieves thermally activated delayed fluorescence properties. Simultaneously, a smaller ΔE... ST It can also improve the efficiency of the reverse intersystem crossing process, so OLED devices using this type of compound can achieve high luminous efficiency while effectively reducing the turn-on voltage.

[0041] The compounds provided by this invention enhance molecular rigidity by introducing rigid donors, which effectively suppresses nonradiative transitions in excited states and contributes to improving fluorescence quantum yield. This molecular design strategy offers a new approach for developing highly efficient red photothermally activated delayed fluorescence materials. Attached Figure Description

[0042] Figure 1 The image shows the UV-Vis absorption and fluorescence emission spectra of the compound prepared in Example 1 of this invention in a diluted toluene solution. Figure 2 The UV-Vis absorption and fluorescence emission spectra of the compound prepared in Example 4 of this invention in a diluted toluene solution are shown.

[0043] Figure 3 The image shows the UV-Vis absorption and fluorescence emission spectra of the compound prepared in Example 6 of this invention in a diluted toluene solution.

[0044] Figure 4 This is a schematic diagram of the structure of the organic electroluminescent devices prepared in Application Examples 1-3 of the present invention.

[0045] Figure 5 The diagram shows the functional layer molecular structure of the organic electroluminescent devices prepared in Examples 1-3 of this invention.

[0046] Figure 6This is a schematic diagram of the structure of the superfluorescent device prepared in Application Example 4 of the present invention.

[0047] Figure 7 The molecular structure of FSBN, the luminescent guest material of the superfluorescent device prepared in Application Example 4 of this invention, is shown below.

[0048] Figure 8 The electroluminescence spectra of the organic electroluminescent devices prepared in Examples 1-3 of this invention are shown.

[0049] Figure 9 The graph shows the variation of the maximum external quantum efficiency with brightness for the organic electroluminescent devices prepared in Examples 1-3 of this invention.

[0050] Figure 10 The electroluminescence spectra of the superfluorescent device prepared in Application Example 4 of this invention and the comparative device are shown.

[0051] Figure 11 The graph shows the maximum external quantum efficiency as a function of brightness for the superfluorescent device prepared in Application Example 4 of this invention and the comparative device. Detailed Implementation

[0052] This invention provides a compound, its preparation method, and an electronic device thereof. To make the objectives, technical solutions, and effects of this invention clearer and more explicit, the invention is further described in detail below. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the invention.

[0053] The structural formulas of compounds (a), (b), (c), (d), (e), and (f) prepared in the following embodiments of the present invention are as follows:

[0054]

[0055] Example 1

[0056] The preparation of compound (a) includes the following steps:

[0057] (1) Preparation of Compound 2: A 200 mL side-necked flask was filled with m-trifluoromethylphenol (17.82 g, 110 mmol), 2,5-dibromo-1,3-difluorobenzene (13.60 g, 50 mmol), cesium carbonate (16.56 g, 120 mmol), and 120 mL of N,N-dimethylformamide under argon protection. The reaction was carried out at 120 °C for 8 hours. After cooling to room temperature, the product was filtered through diatomaceous earth and extracted three times with DCM and water. The combined organic phases were 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 the eluent, yielding 23.02 g of a white solid, with a yield of 82.8%. The synthetic process of the above reaction is as follows:

[0058]

[0059] 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).

[0060] (2) Preparation of Compound 3: A 200 mL pressure-resistant bottle was filled with Compound 2 (8.34 g, 15 mmol) and 60 mL of o-dichlorobenzene (o-DCB) under argon protection, and stirred for 0.3 h. A solution of n-butyllithium in pentane (10.31 mL, 1.60 M, 16.5 mmol) was slowly added at 0 °C, and the mixture was stirred for 0.5 h, then allowed to react at room temperature for 1 h, followed by a reaction at 60 °C for 0.3 h. After removing low-boiling molecules such as pentane under vacuum, boron tribromide (1.5 mL, 15 mmol) was added at 0 °C. The reaction mixture was stirred at room temperature for 0.5 h, then allowed to react at room temperature for 1 h. Next, N,N-diisopropylethylamine (3.88 g, 30 mmol, abbreviated as DIPEA) was added at 0 °C. The reaction mixture was then allowed to cool to room temperature, then heated to 180 °C and stirred overnight. After cooling to room temperature, the mixture was filtered through diatomaceous earth and extracted three times with DCM and water. The combined organic phases were 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 give 2.20 g of a white solid, in 30.3% yield. The synthetic process of the above reaction is as follows:

[0061]

[0062] 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).

[0063] (3) Preparation of compound (a): A 200 mL two-necked flask was filled with compound 3 (0.97 g, 2 mmol), compound 4 (0.40 g, 2.2 mmol), tris(dibenzylacetone)dipalladium (0.18 g, 0.2 mmol), tri-tert-butylphosphine tetrafluoroborate (0.12 g, 0.4 mmol), sodium tert-butoxide (0.14 g, 1.5 mmol), and 50 mL of toluene under argon protection. The mixture was reacted at 110 °C for 3 h. After cooling to room temperature, the mixture was filtered through diatomaceous earth and extracted three times with DCM and water. The combined organic phases were 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 the eluent, yielding 0.56 g of an orange solid, with a yield of 47.7%.

[0064]

[0065] 1 H NMR (CDCl3 500MHz) δ (ppm): 8.75 (d, J = 8.0 Hz, 2H), 7.82 (s, 2H), 7.65 (d, J = 8.0 Hz, 2H), 7.31 (s, 2H), 6.88-6.59 (m, 6H), 6.19 (s, 2H).

[0066] 13 C NMR(CDCl3 125MHz)δ(ppm):160.08,159.03,147.13,144.73,136.05,135.79,135.52,135.22,133.36,126.67, 124.50,124.41,123.37,122.53,122.33,120.16,119.45,119.43,116.06,116.02,114.53,110.26.

[0067] Example 2

[0068] The preparation of compound (b) includes the following steps:

[0069] (1) The preparation of compound 3 is the same as in Example 1, and the synthetic route is as follows:

[0070]

[0071] (2) Preparation of compound (b): A 200 mL two-necked flask was filled with compound 3 (1.07 g, 2.2 mmol), compound 4 (0.69 g, 2 mmol), tris(dibenzylacetone)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. The reaction was carried out at 110 °C for 3 h. After cooling to room temperature, the mixture was filtered through diatomaceous earth and extracted three times with DCM and water. The combined organic phases were 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 the eluent, yielding 0.48 g of an orange solid, with a yield of 32%.

[0072]

[0073] HRMS(ESI)m / z calcdfor C 45 H 24 BF6NO3[M+H] + 752.1830, found 752.1822.

[0074] Example 3

[0075] The preparation of compound (c) includes the following steps:

[0076] (1) The preparation of compound 3 is the same as in Example 1, and the synthetic route is as follows:

[0077]

[0078] (2) Preparation of compound (c): A 200 mL two-necked flask was filled with compound 3 (1.07 g, 2.2 mmol), compound 4 (0.73 g, 2 mmol), tris(dibenzylacetone)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. The reaction was carried out at 110 °C for 3 h. After cooling to room temperature, the mixture was filtered through diatomaceous earth and extracted three times with DCM and water. The combined organic phases were 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 the eluent, yielding 0.54 g of an orange solid (35% yield).

[0079]

[0080] HRMS(ESI)m / z calcdfor C 45 H 24BF6NO2S[M+H] + 768.1657, found 768.1642.

[0081] Example 4

[0082] The preparation of compound (d) includes the following steps:

[0083] (1) The preparation of compound 3 is the same as in Example 1, and the synthetic route is as follows:

[0084]

[0085] (2) Preparation of compound (d): A 200 mL two-necked flask was filled with compound 3 (0.97 g, 2 mmol), compound 4 (1.10 g, 2.20 mmol), tris(dibenzylacetone)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. The reaction was carried out at 110 °C for 3 h. After cooling to room temperature, the mixture was filtered through diatomaceous earth and extracted three times with DCM and water. The combined organic phases were 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 the eluent, yielding 0.73 g of a yellow solid (40% yield).

[0086]

[0087] 1 H NMR(CDCl3 500MHz)δ(ppm):8.79(d,J=8.0Hz,2H),7.87(s,2H),7.79(s,2H),7.67(d,J=8.0Hz,2H),7.63(d,J=8.8Hz,2H),7.59(s ,2H),7.28(d,J=2.0Hz,1H),7.26(d,J=2.1Hz,1H),7.22(t,J=7.9Hz,8H),7.09(d,J=7.9Hz,8H),6.96(t,J=7.3Hz,4H).

[0088] 13C NMR(CDCl3 125MHz)δ(ppm):160.18,158.39,148.41,144.92,141.74,137.43,136.00,135.73,135.47,135.28,135.21,129.20,126.71, 126.02,125.00,124.54,123.00,122.37,121.97,120.20,119.53,119.51,118.51,116.06,116.03,113.50,111.12,106.75.

[0089] Example 5

[0090] The preparation of compound (e) includes the following steps:

[0091] (1) Preparation of Compound 2: A 250 mL two-necked flask was filled with m-trifluoromethylphenol (3.24 g, 20 mmol), 2,5-dibromo-1,3-difluorobenzene (5.44 g, 20 mmol), cesium carbonate (5.52 g, 40 mmol), and 60 mL of N,N-dimethylformamide under argon protection. The reaction was carried out at 90 °C for 3 hours. After cooling to room temperature, p-trifluoromethylphenol (3.24 g, 20 mmol) was added under argon protection, and the reaction was continued at 120 °C for 8 hours. After the reaction was completed, the mixture was cooled to room temperature, filtered through diatomaceous earth, and extracted three times with DCM and water. The combined organic phases were 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 the eluent to give 9.5 g of white solid, with a yield of 85%. The synthesis process of the above reaction is as follows:

[0092]

[0093] HRMS(ESI)m / z calcd for C 20 H 10 Br2F6O2[M+H] + 553.9007, found 553.9015.

[0094] (2) Preparation of Compound 3: Compound 2 (8.34 g, 15 mmol) and 60 mL of o-dichlorobenzene were added to a 200 mL pressure-resistant bottle under argon protection and stirred for 0.3 h. A solution of n-butyllithium in pentane (10.31 mL, 1.60 M, 16.5 mmol) was slowly added at 0 °C, and the mixture was stirred for 0.5 h, then allowed to react at room temperature for 1 h, followed by a reaction at 60 °C for 0.3 h. After removing low-boiling molecules such as pentane under vacuum, boron tribromide (1.5 mL, 15 mmol) was added at 0 °C. The reaction mixture was stirred at room temperature for 0.5 h, then allowed to react at room temperature for 1 h. Next, N,N-diisopropylethylamine (3.88 g, 30 mmol) was added at 0 °C. The reaction mixture was then allowed to cool to room temperature, raised to 180 °C, and stirred overnight. After cooling to room temperature, the mixture was filtered through diatomaceous earth and extracted three times with DCM and water. The combined organic phases were 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 give 1.9 g of a white solid, with a yield of 26%. The synthetic process of the above reaction is as follows:

[0095]

[0096] HRMS(ESI)m / z calcd for C 20 H8BBrF6O2[M+H] + 484.9728, found 484.9737.

[0097] (3) Preparation of compound (e): A 200 mL two-necked flask was filled with compound 3 (1.07 g, 2.2 mmol), compound 4 (1.03 g, 2 mmol), tris(dibenzylacetone)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. The reaction was carried out at 110 °C for 3 h. After cooling to room temperature, the mixture was filtered through diatomaceous earth and extracted three times with DCM and water. The combined organic phases were 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 the eluent, yielding 0.65 g of an orange solid (35% yield).

[0098]

[0099] HRMS(ESI)m / z calcd for C 57 H 36 BF6N3O2[M+H] + 920.2801, found 920.2818.

[0100] Example 6

[0101] The preparation of compound (f) includes the following steps:

[0102] (1) The preparation of compound 3 is the same as in Example 1, and the synthetic route is as follows:

[0103]

[0104] (2) Preparation of compound (f): A 200 mL two-necked flask was filled with compound 3 (1.07 g, 2.2 mmol), compound 4 (1.06 g, 2 mmol), tris(dibenzylacetone)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. The reaction was carried out at 110 °C for 3 h. After cooling to room temperature, the mixture was filtered through diatomaceous earth and extracted three times with DCM and water. The combined organic phases were 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 the eluent, yielding 0.72 g of an orange solid (39% yield).

[0105]

[0106] HRMS(ESI)m / z calcd for C 58 H 38 BF6N3O2[M+H] + 934.3026, found 934.3036.

[0107] The compounds prepared in Examples 1, 4, and 6 were subjected to photophysical property testing and electroluminescence performance testing.

[0108] Figure 1-3 The UV-Vis absorption and fluorescence emission spectra of the compounds prepared in Examples 1, 4, and 6 in diluted toluene solution are shown respectively. From the UV-Vis absorption spectra, it can be seen that compounds (a) and (d) have two characteristic absorption bands. The absorption wavelengths of compound (a) are 388 and 452 nm, the absorption wavelengths of compound (d) are 380 and 440 nm, and the absorption wavelength of compound (f) is 384 nm. From the fluorescence emission spectra, it can be seen that the maximum emission wavelengths of the three compounds are 602 nm, 595 nm, and 615 nm, respectively.

[0109] Application Example 1

[0110] The compound prepared in Example 1 was used as the light-emitting layer in an organic electroluminescent device, and the organic electroluminescent device was prepared by vacuum evaporation.

[0111] Application Example 2

[0112] The compound prepared in Example 4 was used as the light-emitting layer in an organic electroluminescent device, and the organic electroluminescent device was prepared by vacuum evaporation.

[0113] Application Example 3

[0114] The compound prepared in Example 6 was used as the light-emitting layer in an organic electroluminescent device, and the organic electroluminescent device was prepared by vacuum evaporation.

[0115] Application Example 4

[0116] The compound prepared in Example 1 was used as a sensitizer in the superfluorescent device, and FSBN was used as the luminescent guest material in the superfluorescent device. The superfluorescent device was prepared by vacuum evaporation. In addition, a control device was prepared by vacuum evaporation without the addition of a sensitizer, containing only the host material (DMIC-TRZ) and the red luminescent guest material (FSBN).

[0117] The organic electroluminescent devices fabricated in the above application examples 1-3 have the following structures: Figure 4 As shown, the specific structure is ITO / HAT-CN / TAPC / TCTA / mCBP / DMIC-TRZ: the compound prepared in the example / ANT-BIZ / Liq / Al, with a doping mass ratio of 10% in the host material DMIC-TRZ. The specific functional layer molecular structure is as follows. Figure 5 As shown.

[0118] The structure of the superfluorescent device prepared in Application Example 4 above is as follows: Figure 6 As shown, the specific structure is ITO / HAT-CN / TAPC / TCTA / mCBP / DMIC-TRZ: the compound prepared in the example, FSBN / POT2T / ANT-BIZ / Liq / Al, with the doping mass ratios of the compound and FSBN in the host material DMIC-TRZ being 10% and 1%, respectively. The molecular structure of the luminescent guest material FSBN is shown below. Figure 7 As shown.

[0119] Figure 8 The figure shows the electroluminescence spectra of the organic electroluminescent devices prepared in Examples 1-3. It can be seen from the figure that the maximum emission wavelengths of compounds (a), (d) and (f) in the organic electroluminescent devices are 570 nm, 570 nm and 577 nm, respectively, which are significantly blue-shifted compared to the wavelengths in solution.

[0120] Figure 9The graph shows the maximum external quantum efficiency as a function of brightness for the organic electroluminescent devices prepared in Examples 1-3. As can be seen from the graph, the maximum external quantum efficiencies of compounds (a), (d), and (f) in the organic electroluminescent devices are 26.3%, 33.1%, and 31.6%, respectively, at a brightness of 10000 cd / m². 2 The maximum external quantum efficiencies are 24.5%, 26.0%, and 28.3%, respectively. Specific device efficiencies are shown in Table 1.

[0121] Table 1

[0122]

[0123] Figure 10 The electroluminescence spectra of the superfluorescent device prepared by application example 4 and the unsensitized control device are shown in the figure. It can be seen from the figure that the maximum emission wavelength in both the superfluorescent device and the control device is 621 nm, which indicates the efficient energy transfer between the sensitizer and the luminescent guest material FSBN in the superfluorescent device.

[0124] Figure 11 The graph shows the maximum external quantum efficiency as a function of brightness for the superfluorescent device sensitized in Example 4 and the unsensitized control device. As can be seen from the graph, the maximum external quantum efficiencies of the superfluorescent device and the control device are 39.9% and 37.5%, respectively, at a brightness of 10000 cd / m². 2 The maximum external quantum efficiencies are 17.0% and 7.6%, respectively. Specific device efficiencies are shown in Table 2.

[0125] Table 2

[0126]

[0127] It should be understood that the application of the present invention is not limited to the examples above. Those skilled in the art can make improvements or modifications based on the above description, and all such improvements and modifications should fall within the protection scope of the appended claims.

Claims

1. A compound, characterized in that, The general molecular structural formula of the compound is shown below: Wherein, R is selected from one of the following structures: Among them, X1-X2 are each independently selected from one of the following: oxygen atom, sulfur atom, selenium atom, and nitrogen atom; X3-X4 are each independently selected from one of the following structures: X5-X6 are each independently selected from any one of the alkyl groups.

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

3. A method for preparing the compound according to any one of claims 1-2, characterized in that, The preparation method includes the following steps: Trifluoromethylphenol was reacted with 2,5-dibromo-1,3-difluorobenzene in the presence of cesium carbonate to give an unclosed intermediate. The unclosed intermediate was mixed with n-butyllithium, and boron tribromide and N,N-diisopropylethylamine were added sequentially to react and obtain a boron-oxygen fused ring acceptor. The boron-oxygen fused ring acceptor and donor R were mixed in a toluene solution, and the compound was obtained by a Buchwald-Hartwig cross-coupling reaction in the presence of tris(dibenzylacetone)dipalladium, tri-tert-butylphosphine tetrafluoroborate and sodium tert-butoxide. The above synthetic route is as follows:

4. The method for preparing the compound according to claim 3, characterized in that, The nucleophilic reaction is carried out at a temperature of 120-150°C for 8-24 hours.

5. The method for preparing the compound according to claim 3, characterized in that, The Buchwald-Hartwig cross-coupling reaction is carried out at a temperature of 110-130°C for 1-3 hours.

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

7. The electronic device according to claim 6, characterized in that, The electronic device is an organic electroluminescent device, which includes a light-emitting layer comprising the compound according to any one of claims 1-2.

8. The electronic device according to claim 7, characterized in that, The light-emitting layer also includes a host material, with the compound serving as a guest material, and the mass ratio of the host material to the guest material is 5 to 30:

1.

9. The electronic device according to claim 6, characterized in that, The electronic device is a superfluorescent device, which includes a light-emitting layer comprising a host material, a guest material, and a sensitizer, wherein the sensitizer is a compound as described in any one of claims 1-2.

10. The electronic device according to claim 9, characterized in that, The mass ratio of the guest material to the host material is 0.5 to 5:100, and the mass ratio of the sensitizer to the host material is 5 to 30:100.

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