Anthracene-based derivatives based on boron-nitrogen multiple resonance skeleton, preparation and application thereof

Abstract

The application belongs to the field of preparation and application of organic photoelectric materials, and discloses a kind of anthryl derivative based on boron-nitrogen multiple resonance skeleton, its preparation and application, the anthryl derivative has general structure as indicated in at least one of general formula A-1 to general formula A-4.Through improving the chemical structure of anthryl derivative, general formula A-1 to general formula A-4 (R1, R2 group in each general formula meets the requirement of specific group) with specific chemical structure are formed, the obtained anthryl derivative can be based on boron-nitrogen multiple resonance effect and triplet-triplet fusion effect (TTF) at the same time, especially can be applied to organic electroluminescent device (OLED) light-emitting layer as guest light-emitting material, host light-emitting material and hybrid host light-emitting material, so as to obtain high-efficiency, low driving voltage, long-life blue light narrow emission OLED device.

Description

TECHNICAL FIELD

[0001] The present application belongs to the field of organic optoelectronic material preparation and application, more particularly, to a kind of anthracene derivative based on boron-nitrogen multiple resonance skeleton, its preparation and application. BACKGROUND

[0002] Organic light-emitting diodes (OLED) have been widely used in the field of light-emitting and display due to their high efficiency, long life and flexible folding advantages. With the development of OLED, the consumer demand for OLED-related technology is constantly increasing, which requires structural reform on the supply side of OLED, i.e. improving the performance of OLED products on the supply side, so as to better meet the expectations of consumers and save energy. The current organic light-emitting materials generally face some prominent disadvantages, such as the problem of too wide emission spectrum full width at half maximum (FWHM) (> 50 nm), which significantly reduces the color purity of OLED light-emitting, so that OLED cannot directly realize high color purity and wide color gamut display, and there is an urgent need for corresponding solutions.

[0003] The third generation of thermally activated delayed fluorescence materials (TADF) can theoretically utilize triplet excitons for delayed fluorescence emission through reverse intersystem crossing (RISC) in small organic molecules, thereby achieving a theoretical internal quantum efficiency of 100%. It is expected to replace existing traditional fluorescent and phosphorescent materials, and TADF materials have significant advantages in cost and efficiency. However, most donor-acceptor type (D-A) TADF materials still have a large FWHM, which is caused by strong intramolecular structural relaxation. In order to solve the problem of wide FWHM, Professor T. Hatakeyama of Gakushuin University and others developed polycyclic aromatic hydrocarbons (PAHs) embedded with heteroatoms, which achieved HOMO / LUMO separation at atomic scale through opposite resonance effect by embedding electron-withdrawing atom boron (B) and electron-donating atom nitrogen (N). This kind of material is collectively referred to as thermally induced delayed fluorescence material with multiple resonance effect (MR-TADF), and the HOMO / LUMO separation at atomic scale greatly weakens the structural relaxation, thereby making MR-TADF material obtain extremely narrow FWHM, greatly improving the color purity, and this material also retains the characteristics of TADF, which is the TADF material with the greatest potential at present. However, the MR-TADF material system is currently scarce, especially the selection of blue MR-TADF light-emitting molecules is less, and the lifetime of blue OLED is not good, so it is urgent to develop new blue MR-TADF light-emitting bodies.

[0004] A group of single boron derivatives based on fluorene-based aniline fusion donor, its preparation and application (see Chinese patent CN 202210431760.2) were obtained by the inventors' research group in the early stage. A rigid group of fluorene derivatives is introduced on the basis of retaining an electron-rich N atom to form a new fusion donor. This kind of single boron derivative based on fluorene-based aniline fusion donor can achieve FWHM below 30 nm based on B-N resonance effect, which can effectively improve the color purity of OLED devices. However, although the triplet exciton in the TADF material can return to the singlet state through reverse intersystem crossing, there is still a serious problem of triplet exciton quenching due to the low rate of reverse intersystem crossing. Therefore, the lifetime problem is still a major problem limiting the development of blue OLED, and a new method is urgently needed to prevent the accumulation of triplet excitons and improve the lifetime of OLED devices. SUMMARY

[0005] In view of the above defects or improvement needs of the prior art, the purpose of the present application is to provide a kind of anthracene derivative based on boron-nitrogen multiple resonance skeleton, its preparation and application, wherein the chemical structure of anthracene derivative is improved to form general formula A-1 to general formula A-4 (R1, R2 group in each general formula meets the specific group requirement), the obtained anthracene derivative can simultaneously based on boron-nitrogen multiple resonance effect and triplet-triplet fusion effect (TTF), especially can be applied to organic electroluminescent device (OLED) light-emitting layer as guest light-emitting material, host light-emitting material and hybrid host light-emitting material, thereby obtaining high efficiency, low driving voltage, long life blue light narrow emission OLED device.

[0006] To achieve the above-mentioned purpose, according to one aspect of the present application, a kind of anthracene derivative based on boron-nitrogen multiple resonance skeleton is provided, characterized in that the anthracene derivative has the general structure as shown in at least one of general formula A-1 to general formula A-4:

[0007]

[0008] Wherein, R1 group is selected from: hydrogen, deuterium, methyl, tert-butyl, trifluoromethyl, phenyl, naphthyl, anthracene group;

[0009] R2 group is selected from: hydrogen, deuterium, methyl, phenyl, methoxy, trifluoromethyl, tert-butyl, naphthyl, anthracene group, silane group, halogen, pyrazine, pyridine, pyrimidine, pyrazine, benzimidazole ring, indolocarbazole, carbazole, phenoxazine, phenothiazine, phenoselenazine, phenanthroimidazole, substituted or unsubstituted C2~C 10 Straight-chain alkyl, substituted or unsubstituted C2~C 10 Straight-chain alkyl, substituted or unsubstituted C2~C 30 Straight-chain alkyl, substituted or unsubstituted C2~C 10Alkoxy, substituted or unsubstituted C1-C 10 Alkylamino, substituted or unsubstituted C2-C 10 Silyl group.

[0010] As a further preferred embodiment of the present invention, the R1 group is hydrogen, methyl, trifluoromethyl, tert-butyl or phenyl;

[0011] The R2 group can be a benzimidazole ring, indolecarbazole, carbazole, phenoxazine, phenothiazine, phenselenazine, methyl, trifluoromethyl, tert-butyl, or phenyl.

[0012] As a further preferred embodiment of the present invention, the anthracene derivative has the structural formula shown in any one of Formulas 1 to 132:

[0013]

[0014]

[0015]

[0016]

[0017]

[0018]

[0019] According to another aspect of the present invention, the present invention provides the application of the above-mentioned anthracene derivatives based on boron-nitrogen multiple resonance framework in the light-emitting layer of organic electroluminescent devices.

[0020] As a further preferred embodiment of the present invention, the organic electroluminescent device comprises, in sequence: an anode, a hole injection layer, a hole transport layer, a light-emitting layer, an electron transport layer, an electron injection layer, and a cathode;

[0021] Preferably, an electron blocking layer or an exciton blocking layer is further disposed between the hole transport layer and the light-emitting layer; a hole blocking layer or an exciton blocking layer is further disposed between the light-emitting layer and the electron transport layer.

[0022] As a further preferred embodiment of the present invention, the anthracene derivative based on the boron-nitrogen multi-resonance framework is specifically applied as a guest luminescent material, a host luminescent material, or a hybrid host luminescent material in the luminescent layer of an organic electroluminescent device.

[0023] Compared with the prior art (especially the reported MR-TADF compounds), the anthracene derivative with the boron-nitrogen resonance skeleton in the application has the multiple resonance effect, the thermally delayed fluorescence property and the triplet-triplet fusion (TTF) ability, which narrows the half peak width of the light-emitting spectrum and realizes the high-efficiency fluorescent emission. Therefore, when the anthracene derivative is applied in the light-emitting layer structure of the organic electroluminescent device (OLED) as a light-emitting guest or host, the color purity, efficiency and service life of the OLED are improved. In addition, the intermolecular stacking is inhibited after the introduction of the bulky anthracene group, so that the concentration quenching is inhibited, the device efficiency is still high in the device with a relatively high concentration of light-emitting molecules, and the efficiency roll-off is weakened.

[0024] On the basis of the boron-nitrogen multiple resonance skeleton, the anthracene group is introduced to form a new blue light-emitting material (the light-emitting wavelength meets 430-495 nm). The anthracene derivative based on the multiple resonance has a large volume and rigidity, and the anthracene group is offset at a certain angle relative to the multiple resonance skeleton, so that the spatial steric hindrance of the molecule is enhanced and the π-π stacking is inhibited, thereby inhibiting the concentration quenching. More importantly, because the triplet exciton lifetime of the MR-TADF molecule is generally long, the reverse intersystem crossing process is weak, and the triplet exciton quenching is prone to occur. The triplet energy level of the traditional anthracene derivative is low, and the light-emitting mechanism thereof is generally the triplet-triplet fusion (TTF). The principle is that two low-energy triplet exciton molecules (the energy level relationship generally meets 2T1 > S1) collide to generate a high-energy singlet exciton molecule and a ground state molecule, which helps to avoid the triplet exciton quenching, thereby improving the service life and stability of the OLED device. Therefore, the anthracene structure and the MR structure are combined for the first time in the application to create a new MR-TADF-TTF type molecule, which can be applied to a light-emitting guest and a light-emitting host. Based on the RISC and TTF synergistic effect of the triplet exciton utilization mechanism, the concentration quenching is inhibited, and the triplet exciton quenching of the MR-TADF molecule is inhibited due to the TTF property of the anthracene itself. The anthracene derivative in the application can realize a half peak width (FWHM) of less than 30 nm based on the boron-nitrogen multiple resonance effect and the triplet-triplet fusion effect (TTF), which can effectively improve the color purity and service life of the OLED device and can be used to prepare a blue light-emitting OLED device with high efficiency, low driving voltage and long service life.

[0025] Specifically, the application can achieve the following beneficial effects:

[0026] (1) The anthracene-based derivative based on the boron-nitrogen multiple resonance skeleton in the application can expand the MR-TADF-TTF type new light-emitting molecular system by combining anthracene and multiple resonance B-N structure, so as to solve the problem of lack of multiple resonance B-N structure material system.

[0027] (2) The anthracene is wrapped outside the boron-nitrogen conjugated skeleton in the application, and when used as a guest light-emitting material, a three-state exciton utilization mechanism of RISC and TTF synergistic effect can be constructed, and the accumulated three-state excitons can be exported in time, so as to avoid the annihilation caused by a large number of exciton accumulation, so that the MR-TADF material can utilize more three-state excitons to emit light, so as to improve the overall lifetime and efficiency of the device, and finally realize a narrow-emission OLED blue light device with high efficiency, low roll-off and long service life.

[0028] (3) The anthracene-based derivative based on the boron-nitrogen multiple resonance skeleton in the application, based on the introduction of anthracene group with a lowest three-state excited state energy level of only 1.8eV, as a host light-emitting material or a mixed host light-emitting material, is beneficial to export the accumulated three-state excitons of the guest material, thereby improving the efficiency and lifetime of the OLED device. BRIEF DESCRIPTION OF DRAWINGS

[0029] Figure 1 It is a schematic diagram of an electroluminescent device structure.

[0030] Figure 2 It is the external quantum efficiency-current density relationship characteristic curve of device examples 1, 4, 7 and 10.

[0031] Figure 3 It is a driving voltage comparison chart of device examples 1, 4, 7, 10 and device comparative example 1.

[0032] Figure 4 It is a device lifetime LT95 comparison chart of device examples 1, 4, 7, 10 and device comparative example 1.

[0033] Figure 5 It is a device lifetime LT95 comparison chart of device examples 13 to 20 and device comparative example 1. DETAILED DESCRIPTION

[0034] In order to make the purpose, technical scheme and advantages of the application clearer, the application will be further described in detail below in combination with the drawings and examples. It should be understood that the specific examples described herein are only used to explain the application and not to limit the application. In addition, the technical features involved in each embodiment of the application described below can be combined with each other as long as they do not conflict with each other.

[0035] In general, the anthracene derivative based on the boron-nitrogen multiple resonance skeleton in the present application has a general structure as shown in at least one of general formula A-1 to general formula A-4:

[0036]

[0037] wherein the R1 group is selected from the group consisting of hydrogen, deuterium, methyl, tert-butyl, trifluoromethyl, phenyl, naphthyl, anthracene; the R2 group is selected from the group consisting of hydrogen, deuterium, methyl, phenyl, methoxy, trifluoromethyl, tert-butyl, naphthyl, anthracene, silyl, halogen, pyrazine, pyridine, pyrimidine, pyrazine, benzimidazole ring, indolocarbazole, carbazole, phenoxazine, phenothiazine, phenoselenazine, phenanthroimidazole, substituted or unsubstituted C2-C 10 linear alkyl, substituted or unsubstituted C2-C 10 branched alkyl, substituted or unsubstituted C7-C 30 aryl, substituted or unsubstituted C2-C 10 alkoxy, substituted or unsubstituted C1-C 10 alkylamino, substituted or unsubstituted C2-C 10 silyl.

[0038] Based on the present application, 132 specific anthracene derivatives can be obtained, and their structural formulas are as follows:

[0039]

[0040]

[0041]

[0042]

[0043]

[0044]

[0045] wherein the compounds of formula 1 to formula 32 satisfy general formula A-1, the compounds of formula 33 to formula 64 satisfy general formula A-2, the compounds of formula 65 to formula 96 satisfy general formula A-3, and the compounds of formula 97 to formula 132 satisfy general formula A-4.

[0046] The following is a synthesis example (the raw materials used, except for the specifically stated, are commercially available):

[0047] Synthesis Example 1

[0048] The anthracene derivative based on the boron-nitrogen multiple resonance skeleton 1 in the present application satisfies general formula A-1, and the structure is as follows:

[0049]

[0050] The method of preparation comprises the following steps:

[0051]

[0052] (1) DABNACl (synthesized in-house by referring to prior art, ref: Li, H.; Yan, H.; Meng, L.; Zhang, X.; Kuang, C.; Meng, Z.; He, Y.; Xu, H.; Zhang, X.; Zheng, Y.; et al. Regioisomeric effects of dibenzofuran on the properties of boron-nitrogen multiple resonance emissive materials. J. Mater. Chem. C 2023, 11 (44), 15548-15554) (5.00 g, 10.99 mmol), bis(4-chlorophenyl)amine (2.88 g, 12.09 mmol), tris(dibenzylideneacetone)dipalladium (0.50 g, 0.55 mmol), tri-tert-butylphosphine tetrafluoroborate (0.32 g, 1.10 mmol), sodium tert-butoxide (3.17 g, 32.98 mmol), dry toluene (60 mL) were taken in a 250 ml three necked flask, purged with nitrogen for 15 minutes, then heated to 120 °C under nitrogen environment and stirred for 12 hours, after completion of the reaction, cooled to room temperature, washed with dichloromethane and water, collected the organic layer, dried and concentrated, column chromatography was performed for preliminary purification, the crude product was further recrystallized with dichloromethane and methanol to obtain a bright yellow solid powder with a yield of 77%.

[0053]

[0054] (2) The product of the first step (5.00 g, 7.62 mmol), 10-chloroanthracene-9-boronic acid (3.91 g, 15.24 mmol), tetrakis(triphenylphosphine)palladium (0.44 g, 0.38 mmol), potassium carbonate (6.32 g, 45.72 mmol), toluene (60 mL), ethanol (20 mL), water (20 mL) were taken in a 250 ml three necked flask, purged with nitrogen for 15 minutes, then heated to 100 °C under nitrogen environment and stirred for 20 hours, after completion of the reaction, cooled to room temperature, washed with dichloromethane and water, collected the organic layer, dried and concentrated, column chromatography was performed for preliminary purification, the crude product was further recrystallized with dichloromethane and methanol to obtain a bright yellow solid powder with a yield of 85%.

[0055]

[0056] (3) The second step product (5.00 g, 4.96 mmol), phenoxazine (1.82 g, 9.92 mmol), tris-dibenzylideneacetone palladium (0.23 g, 0.25 mmol), tri-tert-butylphosphine tetrafluoroborate (0.15 g, 0.50 mmol), sodium tert-butoxide (2.86 g, 29.76 mmol), dry toluene (60 mL) were added into a 250 ml three-necked flask, nitrogen was blown for 15 minutes, then heated to 120°C under the environment of nitrogen and stirred for 18 hours. After the reaction was completed, it was cooled to room temperature, extracted with dichloromethane and water, the organic layer was collected, dried and concentrated, and column chromatography was used for preliminary purification. The crude product was further recrystallized with dichloromethane and methanol to obtain a bright yellow solid powder with a yield of 80%.

[0057] The characterization results of the anthracene derivative 1 of the boron-nitrogen multiple resonance skeleton are as follows: the mass spectrum is 1302.49; and the nuclear magnetic results are as follows:

[0058] 1 H NMR (500 MHz, Chloroform-d) δ 8.18 (dd, J = 7.5, 1.6 Hz, 1H), 8.11-8.05 (m, 1H), 7.59 (td, J = 8.0, 1.4 Hz, 1H), 7.53 (td, J = 7.7, 1.4 Hz, 1H), 7.52-7.46 (m, 1H), 7.44-7.34 (m, 2H), 7.37-7.13 (m, 4H), 7.09-6.98 (m, 1H), 6.92 (ddd, J = 15.9, 8.0, 1.2 Hz, 1H).

[0059] Synthesis Example 2

[0060] The anthracene derivative 33 of the boron-nitrogen multiple resonance skeleton according to the present application conforms to the general formula A-2, and the structure is as follows:

[0061]

[0062] The preparation method comprises the following steps:

[0063]

[0064] (1) DABNACl (5.00 g, 10.99 mmol), bis(4-chlorophenyl)amine (2.88 g, 12.09 mmol), tris(dibenzylideneacetone)dipalladium(0) (0.50 g, 0.55 mmol), tri-tert-butylphosphine tetrafluoroborate (0.32 g, 1.10 mmol), sodium tert-butoxide (3.17 g, 32.98 mmol), dry toluene (60 mL) were added to a 250 ml three necked flask, purged with nitrogen for 15 minutes, then heated to 120 °C under nitrogen environment and stirred for 12 hours. After the reaction was completed, it was cooled to room temperature, washed with dichloromethane and water, the organic layer was collected, dried and concentrated, and column chromatography was performed for preliminary purification. The crude product was further recrystallized with dichloromethane and methanol to obtain a bright yellow solid powder with a yield of 77%.

[0065]

[0066] (2) The product of the first step (5.00 g, 7.62 mmol), pinacol borate (7.74 g, 30.48 mmol), tris(dibenzylideneacetone)dipalladium(0) (0.44 g, 0.38 mmol), tri-tert-butylphosphine tetrafluoroborate (0.22 g, 0.76 mmol), sodium acetate (1.25 g, 15.24 mmol), 1,4-dioxane (60 mL) were added to a 250 ml three necked flask, purged with nitrogen for 15 minutes, then heated to 110 °C under nitrogen environment and stirred for 18 hours. After the reaction was completed, it was cooled to room temperature, washed with dichloromethane and water, the organic layer was collected, dried and concentrated, and column chromatography was performed for preliminary purification. The crude product was further recrystallized with dichloromethane and methanol to obtain a bright yellow solid powder with a yield of 90%.

[0067]

[0068] (3) The product of the second step (5.00 g, 5.96 mmol), 1,2-dibromoethane (2.35 g, 12.56 mmol), tetrakis(triphenylphosphine)palladium(0) (0.35 g, 0.30 mmol), potassium carbonate (2.47 g, 17.88 mmol), toluene (60 mL), ethanol (20 mL), water (20 mL) were added to a 250 ml three necked flask, purged with nitrogen for 15 minutes, then heated to 100 °C under nitrogen environment and stirred for 24 hours. After the reaction was completed, it was cooled to room temperature, washed with dichloromethane and water, the organic layer was collected, dried and concentrated, and column chromatography was performed for preliminary purification. The crude product was further recrystallized with dichloromethane and methanol to obtain a bright yellow solid powder with a yield of 50%.

[0069]

[0070] (4) The product of the above third step (5.00 g, 6.24 mmol), 10-chloroanthracene-9-boronic acid (3.36 g, 13.10 mmol), tetrakis(triphenylphosphine)palladium (0.35 g, 0.30 mmol), potassium carbonate (3.42 g, 18.72 mmol), toluene (60 mL), ethanol (20 mL), water (20 mL) were added into a 250 ml three-necked flask, purged with nitrogen for 15 minutes, then heated to 100 °C under refluxing with stirring for 20 hours under nitrogen. After the reaction was completed, it was cooled to room temperature, washed with dichloromethane and water, and the organic layer was collected, dried, concentrated, and subjected to column chromatography for preliminary purification. The crude product was further recrystallized from dichloromethane and methanol to obtain a bright yellow solid powder with a yield of 59%.

[0071]

[0072] (5) The product of the above fourth step (5.00 g, 4.70 mmol), phenoxazine (1.81 g, 9.86 mmol), tris(dibenzylideneacetone)dipalladium (0.23 g, 0.25 mmol), tri-tert-butylphosphine tetrafluoroborate (0.15 g, 0.50 mmol), sodium tert-butoxide (2.86 g, 29.76 mmol), dry toluene (60 mL) were added into a 250 ml three-necked flask, purged with nitrogen for 15 minutes, then heated to 120 °C under refluxing with stirring for 22 hours under nitrogen. After the reaction was completed, it was cooled to room temperature, washed with dichloromethane and water, and the organic layer was collected, dried, concentrated, and subjected to column chromatography for preliminary purification. The crude product was further recrystallized from dichloromethane and methanol to obtain a bright yellow solid powder with a yield of 87%.

[0073] The anthracene derivative 33 of the boron-nitrogen multiple resonance skeleton was characterized, and the mass spectrum was 1357.55; the nuclear magnetic resonance results were as follows:

[0074] 1 H NMR (500 MHz, chloroform-d) δ 8.06 (dd, J = 8.3, 1.4 Hz, 2H), 7.83 (dd, J = 7.7, 1.5 Hz, 2H), 7.61-7.54 (m, 2H), 7.46-7.18 (m, 14H), 7.09-6.88 (m, 11H), 6.55 (s, 1H), 3.43 (dt, J = 16.7, 8.0 Hz, 1H), 3.30 (dt, J = 16.8, 8.0 Hz, 1H), 2.99 (tt, J = 8.0, 1.0 Hz, 2H).

[0075] Synthesis Example 3

[0076] The anthracene derivative 65 of the boron-nitrogen multiple resonance skeleton according to the present application conforms to general formula A-3, and the structure is as follows:

[0077]

[0078] The preparation method comprises the following steps:

[0079]

[0080] (1) BNCzBr (synthesized by referring to the prior art, ref: Zou, Y.; Yu, M.; Xu, Y.; Xiao, Z.; Song, X.; Hu, Y.; Xu, Z.; Zhong, C.; He, J.; Cao, X.; et al. Acceleration of reverse intersystem crossing in multi-resonance TADF emitter. Chem 2024, 10, 1485-1501) (5.00 g, 6.95 mmol), bis (4-chlorophenyl) amine (1.73 g, 7.30 mmol), tris (dibenzylideneacetone) dipalladium (0.32 g, 0.35 mmol), tri-tert-butylphosphine tetrafluoroborate (0.20 g, 0.70 mmol), sodium tert-butoxide (2.00 g, 20.85 mmol), dry toluene (60 mL) were added to a 250 ml three-necked flask, and then nitrogen was blown for 15 minutes, and then the reaction was stirred at 120°C under reflux in a nitrogen environment for 10 hours. After the reaction was completed, it was cooled to room temperature, extracted with dichloromethane and water, and the organic layer was collected, dried and concentrated. Column chromatography was used for preliminary purification, and the crude product was further recrystallized with dichloromethane and methanol to obtain a bright yellow solid powder with a yield of 88%.

[0081]

[0082] (2) The product of the above first step (5.00 g, 5.70 mmol), 10-chloroanthracene-9-boronic acid (3.07 g, 11.97 mmol), tetrakis (triphenylphosphine) palladium (0.43 g, 0.34 mmol), potassium carbonate (4.73 g, 34.20 mmol), toluene (60 mL), ethanol (20 mL), water (20 mL) were added to a 250 ml three-necked flask, and then nitrogen was blown for 15 minutes, and then the reaction was stirred at 100°C under reflux in a nitrogen environment for 24 hours. After the reaction was completed, it was cooled to room temperature, extracted with dichloromethane and water, and the organic layer was collected, dried and concentrated. Column chromatography was used for preliminary purification, and the crude product was further recrystallized with dichloromethane and methanol to obtain a bright yellow solid powder with a yield of 84%.

[0083]

[0084] (3) The product of the above second step (5.00 g, 4.07 mmol), phenoxazine (1.57 g, 8.55 mmol), tris-dibenzylideneacetone palladium (0.18 g, 0.20 mmol), tri-tert-butylphosphonium tetrafluoroborate (0.12 g, 0.40 mmol), sodium tert-butoxide (2.35 g, 24.42 mmol), dry toluene (60 mL) were taken in a 250 ml three necked flask, purged with nitrogen for 15 minutes, then heated to 120 °C under nitrogen environment for 23 hours. After completion of the reaction, it was cooled to room temperature, washed with dichloromethane and water, the organic layer was collected, dried and concentrated. The crude product was purified by column chromatography and further recrystallized from dichloromethane and methanol to obtain a bright yellow solid powder with a yield of 85%.

[0085] The anthracene derivative 65 of boron-nitrogen multiple resonance skeleton was characterized, and the mass spectrum was 1522.71; the nuclear magnetic resonance results were as follows:

[0086] 1 H NMR (500 MHz, Chloroform-d) δ 8.48 (d, J = 2.2 Hz, 1H), 8.18 (dd, J = 7.5, 1.6 Hz, 1H), 8.11-8.05 (m, 1H), 7.90 (t, J = 1.9 Hz, 1H), 7.62-7.46 (m, 4H), 7.35-7.13 (m, 6H), 6.92 (ddd, J = 15.9, 8.0, 1.2 Hz, 1H).

[0087] Synthesis Example 4

[0088] The anthracene derivative 99 of boron-nitrogen multiple resonance skeleton according to the present application conforms to general formula A-4, and the structure is as follows:

[0089]

[0090] The preparation method comprises the following steps:

[0091]

[0092] (1) BNCzBr (5.00 g, 6.95 mmol), bis(4-chlorophenyl)amine (1.73 g, 7.30 mmol), tris(dibenzylideneacetone)dipalladium (0.32 g, 0.35 mmol), tri-tert-butylphosphine tetrafluoroborate (0.20 g, 0.70 mmol), sodium tert-butoxide (2.00 g, 20.85 mmol), dry toluene (60 mL) were added to a 250 ml three necked flask, purged with nitrogen for 15 minutes, then heated to 120 °C under nitrogen environment and stirred for 10 hours. After the reaction was completed, it was cooled to room temperature, washed with dichloromethane and water, the organic layer was collected, dried and concentrated, and column chromatography was performed for preliminary purification. The crude product was further recrystallized with dichloromethane and methanol to obtain a bright yellow solid powder with a yield of 88%.

[0093]

[0094] (2) The product of the first step (5.00 g, 5.70 mmol), pinacol borate (5.79 g, 22.80 mmol), tris(dibenzylideneacetone)dipalladium (0.34 g, 0.29 mmol), tri-tert-butylphosphine tetrafluoroborate (0.17 g, 0.58 mmol), sodium acetate (0.94 g, 11.4 mmol), 1,4-dioxane (60 mL) were added to a 250 ml three necked flask, purged with nitrogen for 15 minutes, then heated to 110 °C under nitrogen environment and stirred for 24 hours. After the reaction was completed, it was cooled to room temperature, washed with dichloromethane and water, the organic layer was collected, dried and concentrated, and column chromatography was performed for preliminary purification. The crude product was further recrystallized with dichloromethane and methanol to obtain a bright yellow solid powder with a yield of 92%.

[0095]

[0096] (3) The product of the second step (5.00 g, 4.71 mmol), 1,2-dibromoethane (1.76 g, 9.42 mmol), tetrakis(triphenylphosphine)palladium (0.28 g, 0.24 mmol), potassium carbonate (1.95 g, 14.13 mmol), toluene (60 mL), ethanol (20 mL), water (20 mL) were added to a 250 ml three necked flask, purged with nitrogen for 15 minutes, then heated to 100 °C under nitrogen environment and stirred for 28 hours. After the reaction was completed, it was cooled to room temperature, washed with dichloromethane and water, the organic layer was collected, dried and concentrated, and column chromatography was performed for preliminary purification. The crude product was further recrystallized with dichloromethane and methanol to obtain a bright yellow solid powder with a yield of 53%.

[0097]

[0098] (4) The product of the above third step (5.00 g, 4.90 mmol), 10-chloroanthracene-9- boronic acid (2.51 g, 9.80 mmol), tetrakis(triphenylphosphine)palladium (0.29 g, 0.25 mmol), potassium carbonate (2.69 g, 14.70 mmol), toluene (60 mL), ethanol (20 mL), water (20 mL) were added into a 250 ml three-necked flask, purged and maintained with nitrogen for 15 minutes, then heated to 100 °C under nitrogen atmosphere and stirred for 18 hours. After completion of the reaction, cooled to room temperature, washed with dichloromethane and water, collected the organic layer, dried and concentrated, purified by column chromatography, the crude product was further recrystallized from dichloromethane and methanol to obtain a bright yellow solid powder with a yield of 64%.

[0099]

[0100] (5) The product of the above fourth step (5.00 g, 3.89 mmol), phenoxazine (2.19 g, 11.93 mmol), tris(dibenzylideneacetone)dipalladium (0.28 g, 0.30 mmol), tri-tert-butylphosphine tetrafluoroborate (0.18 g, 0.61 mmol), sodium tert-butoxide (3.46 g, 36.00 mmol), dry toluene (60 mL) were added into a 250 ml three-necked flask, purged and maintained with nitrogen for 15 minutes, then heated to 120 °C under nitrogen atmosphere and stirred for 24 hours. After completion of the reaction, cooled to room temperature, washed with dichloromethane and water, collected the organic layer, dried and concentrated, purified by column chromatography, the crude product was further recrystallized from dichloromethane and methanol to obtain a bright yellow solid powder with a yield of 90%.

[0101] The anthracene derivative 99 of the boron-nitrogen multi-resonance skeleton was characterized, and the mass spectrum was 1577.77; the nuclear magnetic resonance results were as follows:

[0102] 1 H NMR (500 MHz, Chloroform-d) δ 8.48 (d, J = 2.2 Hz, 1H), 8.06 (dd, J = 8.4, 1.4 Hz, 1H), 7.90 (t, J = 1.9 Hz, 1H), 7.83 (dd, J = 7.6, 1.4 Hz, 1H), 7.61-7.54 (m, 2H), 7.43 (td, J = 7.8, 1.3 Hz, 1H), 7.35-7.18 (m, 4H), 7.06-6.88 (m, 3H), 3.43 (dt, J = 16.6, 8.0 Hz, 1H), 3.30 (dt, J = 16.8, 8.1 Hz, 1H), 2.99 (tt, J = 8.0, 1.0 Hz, 1H), 1.35 (d, J = 0.7 Hz, 10H).

[0103] Similarly, the remaining anthracene derivatives of boron-nitrogen multi-resonance skeleton can be synthesized in a similar manner, wherein, for the compound of general formula A-1, only the DABNACl derivative is reacted with bis(4-chlorophenyl)amine and then reacted with the corresponding anthracene boronic acid derivative to obtain. For the compound of general formula A-2, only the DABNACl derivative is reacted with bis(4-chlorophenyl)amine, esterified and reacted with 1,2-dibromoethane, and then reacted with the corresponding anthracene boronic acid derivative to obtain. For the compound of general formula A-3, only the BNCzBr derivative is reacted with bis(4-chlorophenyl)amine and then reacted with the corresponding anthracene boronic acid derivative to obtain. For the compound of general formula A-4, only the BNCzBr derivative is reacted with bis(4-chlorophenyl)amine, esterified and reacted with 1,2-dibromoethane, and then reacted with the corresponding anthracene boronic acid derivative to obtain.

[0104] The anthracene derivatives of boron-nitrogen multi-resonance skeleton described above can be applied in organic electroluminescent devices, for example, any of the anthracene derivatives of boron-nitrogen multi-resonance skeleton can be used as a guest light-emitting material, a host light-emitting material or a hybrid host light-emitting material in the light-emitting layer of an organic electroluminescent device. Figure 1 An example of an electroluminescent device structure. The corresponding organic electroluminescent device includes a cathode and a transport layer, a light-emitting layer and an injection layer between the cathode, wherein the light-emitting layer contains the anthracene derivatives of boron-nitrogen multi-resonance skeleton in the present application.

[0105] Any of the anthracene derivatives of boron-nitrogen multi-resonance skeleton described in the present application can be used as a guest light-emitting material, a host light-emitting material or a hybrid host light-emitting material in an OLED electroluminescent device. Taking the use of ITO (indium tin oxide) glass substrate as an example, the specific device preparation process may, for example, include: (1) substrate pretreatment, the ITO glass substrate is sequentially ultrasonically cleaned in ITO cleaning agent, isopropanol, acetone, ethanol, deionized water for 30 minutes, dried with nitrogen blowing and dried in an oven at 120°C for 2 hours. Before preparing the device, the ITO glass substrate is subjected to oxygen plasma surface treatment for 5 minutes, then transferred to an organic vacuum chamber to evaporate organic functional layer materials (such as TAPC, mCP and other materials between MoO3 and Al in Device Example 1 below), after completion, transferred to a metal vacuum chamber to evaporate a metal electrode (such as Al in Device Example 1 below). In the specific preparation process, the best host material, exciton blocking layer material or injection and transport layer material can be selected according to the properties of the anthracene derivatives of boron-nitrogen multi-resonance skeleton itself, such as the emission peak position, the lowest singlet and triplet state energy level value; in addition, the film thickness of each functional layer and the concentration of the host-guest doping are also optimized.

[0106] The following are device examples (each organic functional layer is optimized):

[0107] Device Comparative Example 1:

[0108] ITO / MoO3(10 nm) / TAPC(60 nm) / mCP(10 nm) / PPF:Dopant(9 wt%, 20 nm) / PPF(10 nm) / TmPyPB(30 nm) / LiF(1 nm) / Al(100 nm).

[0109] The light-emitting layer guest light-emitting material (Dopant) is a conventional MR-TADF compound PAB (PAB is a typical MR-TADF material, for example, see ref: Wang, Y.; Duan, Y.; Guo, R.; Ye, S.; Di, K.; Zhang, W.; Zhuang, S.; Wang, L. An aperiphery cladding strategy to improve the performance of narrowband emitters, achieving deep-blue OLEDs with CIEy < 0.08 and external quantum efficiency approaching 20%. Org. Electron. 2021, 97, 106275.), the device electroluminescence peak wavelength is 452 nm, the half peak width (FWHM) is 28 nm, the maximum external quantum efficiency (EQE max ) is 21.6%, the driving voltage is 4.0 V, and the device lifetime LT95 is 75 hours @ initial luminance 2000 cd / m 2 .

[0110] Device Comparative Example 1:

[0111] ITO / MoO3(10 nm) / TAPC(60 nm) / mCP(10 nm) / PPF:Dopant(9 wt%, 20 nm) / PPF(10 nm) / TmPyPB(30 nm) / LiF(1 nm) / Al(100 nm).

[0112] The light-emitting layer guest light-emitting material (Dopant) is a boron-nitrogen multi-resonance anthracene derivative 1 described in the application, the device electroluminescence peak wavelength is 448 nm (which is deep blue light; in the art, the wavelength of “deep blue light” is 430 nm to 460 nm), the FWHM is 22 nm, the maximum external quantum efficiency (EQE max ) is 31.1%, the driving voltage is 3.5 V, and the device lifetime LT95 is 130 hours @ initial luminance 2000 cd / m 2 .

[0113] Device Comparative Example 1:

[0114] ITO / MoO3(10 nm) / TAPC(60 nm) / mCP(5 nm) / mCP:Dopant(3 wt%, 20 nm) / PPF(10 nm) / TPBi(30 nm) / LiF(1 nm) / Al(100 nm).

[0115] The light-emitting layer guest light-emitting material (Dopant) is anthracene derivative 2 described in the boron-nitrogen multiple resonance of the application, the electroluminescent peak wavelength of the device is 455 nm, the FWHM is 21 nm, the EQE max is 31.0%, the driving voltage is 3.4 V, the device lifetime LT95 is 140 hours @ initial brightness 2000 cd / m 2 .

[0116] Device Example 3:

[0117] ITO / MoO3(10 nm) / TAPC(60 nm) / mCP(5 nm) / PPF:Dopant(6 wt%, 20 nm) / PPF(5 nm) / TmPyPb(35 nm) / LiF(1 nm) / Al(100 nm).

[0118] The light-emitting layer guest light-emitting material (Dopant) is anthracene derivative 3 described in the boron-nitrogen multiple resonance of the application, the electroluminescent peak wavelength of the device is 442 nm, the FWHM is 18 nm, the EQE max is 35.0%, the driving voltage is 3.4 V, the device lifetime LT95 is 147 hours @ initial brightness 2000 cd / m 2 .

[0119] Device Example 4:

[0120] ITO / MoO3(10 nm) / TAPC(50 nm) / mCP(10 nm) / PPF:Dopant(6 wt%, 20 nm) / PPF(5 nm) / TmPyPb(40 nm) / LiF(1 nm) / Al(100 nm).

[0121] The light-emitting layer guest light-emitting material (Dopant) is anthracene derivative 33 described in the boron-nitrogen multiple resonance of the application, the electroluminescent peak wavelength of the device is 458 nm, the FWHM is 21 nm, the EQE max is 38.1%, the driving voltage is 3.3 V, the device lifetime LT95 is 150 hours @ initial brightness 2000 cd / m 2 .

[0122] Device Example 5:

[0123] ITO / MoO3(10nm) / TAPC(50nm) / TCTA(10nm) / PPF: Dopant(6wt%, 20nm) / PPF(5nm) / TmPyPb(40nm) / Liq(1nm) / Al(100nm).

[0124] The guest luminescent material (Dopant) of the luminescent layer is the boron-nitrogen multiple resonance anthracene derivative 34 described in this invention. This device has an electroluminescence peak wavelength of 445 nm, an FWHM of 21 nm, and an EQE... max The accuracy is 30.4%, the driving voltage is 3.5V, and the device lifetime LT95 is 154 hours @ initial luminance of 2000 cd / m². 2 .

[0125] Device Example 6:

[0126] ITO / MoO3(10nm) / TAPC(60nm) / TCTA(5nm) / PPF: Dopant(6wt%, 20nm) / PPF(10nm) / TmPyPb(30nm) / Liq(1nm) / Al(100nm).

[0127] The guest luminescent material (Dopant) of the luminescent layer is the boron-nitrogen multiple resonance anthracene derivative 35 described in this invention. This device has an electroluminescence peak wavelength of 459 nm, an FWHM of 24 nm, and an EQE... max The accuracy is 34.4%, the driving voltage is 3.4V, and the device lifetime LT95 is 164 hours @ initial luminance of 2000 cd / m². 2 .

[0128] Device Example 7:

[0129] ITO / MoO3(10nm) / TAPC(60nm) / TCTA(5nm) / PPF: Dopant(6wt%, 20nm) / PPF(10nm) / TmPyPb(30nm) / Liq(1nm) / Al(80nm).

[0130] The guest luminescent material (Dopant) of the luminescent layer is the boron-nitrogen multiple resonance anthracene derivative 65 described in this invention. This device has an electroluminescence peak wavelength of 463 nm, an FWHM of 20 nm, and an EQE... max The accuracy is 34.8%, the driving voltage is 3.4V, and the device lifetime LT95 is 159 hours @ initial luminance of 2000 cd / m². 2 .

[0131] Device Example 8:

[0132] ITO / MoO3(10nm) / TAPC(60nm) / TCTA(5nm) / PPF: Dopant(6wt%, 20nm) / PPF(10nm) / TmPyPb(30nm) / Liq(1nm) / Al(80nm).

[0133] The guest luminescent material (Dopant) of the luminescent layer is the boron-nitrogen multiple resonance anthracene derivative 66 described in this invention. This device has an electroluminescence peak wavelength of 467 nm, an FWHM of 25 nm, and an EQE... max The accuracy is 33.7%, the driving voltage is 3.6V, and the device lifetime LT95 is 150 hours @ initial luminance of 2000 cd / m². 2 .

[0134] Device Example 9:

[0135] ITO / MoO3(10nm) / TAPC(60nm) / mCP(5nm) / PPF: Dopant(6wt%, 20nm) / PPF(5nm) / TmPyPb(35nm) / LiF(1nm) / Al(100nm).

[0136] The guest luminescent material (Dopant) of the luminescent layer is the boron-nitrogen multiple resonance anthracene derivative 67 described in this invention. This device has an electroluminescence peak wavelength of 464 nm, an FWHM of 23 nm, and an EQE... max The accuracy is 30.2%, the driving voltage is 3.5V, and the device lifetime LT95 is 170 hours @ initial luminance of 2000 cd / m². 2 .

[0137] Device Example 10:

[0138] ITO / MoO3(10nm) / TAPC(60nm) / mCP(5nm) / PPF: Dopant(3wt%, 20nm) / PPF(5nm) / TmPyPb(40nm) / Liq(1nm) / Al(100nm).

[0139] The guest luminescent material (Dopant) of the luminescent layer is the boron-nitrogen multiple resonance anthracene derivative 99 described in this invention. This device has an electroluminescence peak wavelength of 470 nm, an FWHM of 18 nm, and an EQE... max The accuracy rate is 31.1%, the driving voltage is 3.3V, and the device lifetime LT95 is 168 hours @ initial luminance of 2000 cd / m². 2 .

[0140] Device Example 11:

[0141] ITO / MoO3(10 nm) / TAPC(60 nm) / mCP(5 nm) / PPF:Dopant(3 wt%, 20 nm) / PPF(5 nm) / TPBi(30 nm) / Liq(1 nm) / Al(100 nm).

[0142] The light-emitting layer guest light-emitting material (Dopant) is the anthracene derivative 100 of the boron-nitrogen multiple resonance described in the present application, the electroluminescent peak wavelength of the device is 478 nm, the FWHM is 18 nm, the EQE max is 32.1%, the driving voltage is 3.3 V, the device lifetime LT95 is 160 hours @ initial brightness 2000 cd / m 2 .

[0143] Device Example 12:

[0144] ITO / MoO3(10 nm) / TAPC(60 nm) / mCP(5 nm) / PPF:Dopant(3 wt%, 20 nm) / PPF(5 nm) / TPBi(30 nm) / Liq(1 nm) / Al(100 nm).

[0145] The light-emitting layer guest light-emitting material (Dopant) is the anthracene derivative 101 of the boron-nitrogen multiple resonance described in the present application, the electroluminescent peak wavelength of the device is 481 nm, the FWHM is 22 nm, the EQE max is 37.1%, the driving voltage is 3.4 V, the device lifetime LT95 is 156 hours @ initial brightness 2000 cd / m 2 .

[0146] Device Example 13:

[0147] ITO / MoO3(10 nm) / TAPC(60 nm) / mCP(5 nm) / Host:Dopant(3 wt%, 20 nm) / PPF(5 nm) / TPBi(30 nm) / Liq(1 nm) / Al(100 nm).

[0148] The light-emitting layer host light-emitting material (Host) is the anthracene derivative 1 of the boron-nitrogen multiple resonance described in the present application, the light-emitting layer guest light-emitting material (Dopant) is the conventional MR-TADF compound PAB, the electroluminescent peak wavelength of the device is 452 nm, the FWHM is 28 nm, the EQE max is 24.1%, the driving voltage is 3.6 V, the device lifetime LT95 is 130 hours @ initial brightness 2000 cd / m 2 .

[0149] Device Example 14:

[0150] ITO / MoO3(10nm) / TAPC(60nm) / mCP(5nm) / Host:Dopant(3wt%, 20nm) / PPF(5nm) / TPBi(30nm) / Liq(1nm) / Al(100nm).

[0151] The host luminescent material of the luminescent layer is the boron-nitrogen multiple resonance anthracene derivative 33 described in this invention, and the dopant luminescent material of the luminescent layer is the conventional MR-TADF compound PAB. The device has an electroluminescence peak wavelength of 452 nm, an FWHM of 28 nm, and an EQE... max The accuracy is 23.5%, the driving voltage is 3.5V, and the device lifetime LT95 is 128 hours @ initial luminance of 2000 cd / m². 2 .

[0152] Device Example 15:

[0153] ITO / MoO3(10nm) / TAPC(60nm) / mCP(5nm) / Host:Dopant(3wt%, 20nm) / PPF(5nm) / TPBi(30nm) / Liq(1nm) / Al(100nm).

[0154] The host luminescent material of the luminescent layer is the boron-nitrogen multiple resonance anthracene derivative 65 described in this invention, and the dopant luminescent material of the luminescent layer is the conventional MR-TADF compound PAB. This device has an electroluminescence peak wavelength of 452 nm, an FWHM of 27 nm, and an EQE... max The accuracy is 25.0%, the driving voltage is 3.6V, and the device lifetime LT95 is 140 hours @ initial luminance of 2000 cd / m². 2 .

[0155] Device Example 16:

[0156] ITO / MoO3(10nm) / TAPC(60nm) / mCP(5nm) / Host:Dopant(3wt%, 20nm) / PPF(5nm) / TPBi(30nm) / Liq(1nm) / Al(100nm).

[0157] The host luminescent material of the luminescent layer is the boron-nitrogen multiple resonance anthracene derivative 97 described in this invention, and the dopant luminescent material of the luminescent layer is the conventional MR-TADF compound PAB. This device has an electroluminescence peak wavelength of 453 nm, an FWHM of 28 nm, and an EQE... max The accuracy is 23.9%, the driving voltage is 3.4V, and the device lifetime LT95 is 145 hours @ initial luminance of 2000 cd / m².2 .

[0158] Device Example 17:

[0159] ITO / MoO3(10nm) / TAPC(60nm) / mCP(5nm) / Host:Dopant(3wt%, 20nm) / PPF(5nm) / TPBi(30nm) / Liq(1nm) / Al(100nm).

[0160] The host luminescent material of the luminescent layer is a mixture of the boron-nitrogen multiple resonance anthracene derivative 1 described in this invention and the commercial host material PPF, with a mixing ratio of 1:1 (mass ratio, the same below). The dopant luminescent material of the luminescent layer is the conventional MR-TADF compound PAB. The device has an electroluminescence peak wavelength of 451 nm, an FWHM of 27 nm, and an EQE of... max The accuracy is 25.2%, the driving voltage is 3.6V, and the device lifetime LT95 is 127 hours @ initial luminance of 2000 cd / m². 2 .

[0161] Device Example 18:

[0162] ITO / MoO3(10nm) / TAPC(60nm) / mCP(5nm) / Host:Dopant(3wt%, 20nm) / PPF(5nm) / TPBi(30nm) / Liq(1nm) / Al(100nm).

[0163] The host light-emitting material of the light-emitting layer is a mixture of the boron-nitrogen multiple resonance anthracene derivative 33 described in this invention and the commercial host material PPF, with a mixing ratio of 1:1. The dopant light-emitting material of the light-emitting layer is the conventional MR-TADF compound PAB. The device has an electroluminescence peak wavelength of 453 nm, an FWHM of 28 nm, and an EQE of... max The accuracy is 22.9%, the driving voltage is 3.4V, and the device lifetime LT95 is 125 hours @ initial luminance of 2000 cd / m². 2 .

[0164] Device Example 19:

[0165] ITO / MoO3(10nm) / TAPC(60nm) / mCP(5nm) / Host:Dopant(3wt%, 20nm) / PPF(5nm) / TPBi(30nm) / Liq(1nm) / Al(100nm).

[0166] The host luminescent material of the luminescent layer is a mixture of the boron-nitrogen multiple resonance anthracene derivative 65 described in this invention and the commercial host material PPF, with a mixing ratio of 1:1. The dopant luminescent material of the luminescent layer is the conventional MR-TADF compound PAB. The device has an electroluminescence peak wavelength of 452 nm, an FWHM of 26 nm, and an EQE of... max The accuracy is 25.1%, the driving voltage is 3.7V, and the device lifetime LT95 is 137 hours @ initial luminance of 2000 cd / m². 2 .

[0167] Device Example 20:

[0168] ITO / MoO3(10nm) / TAPC(60nm) / mCP(5nm) / Host:Dopant(3wt%, 20nm) / PPF(5nm) / TPBi(30nm) / Liq(1nm) / Al(100nm).

[0169] The host luminescent material of the luminescent layer is a mixture of the boron-nitrogen multiple resonance anthracene derivative 97 described in this invention and the commercial host material PPF, with a mixing ratio of 1:1. The dopant luminescent material of the luminescent layer is the conventional MR-TADF compound PAB. The device has an electroluminescence peak wavelength of 453 nm, an FWHM of 27 nm, and an EQE of... max The accuracy is 23.5%, the driving voltage is 3.5V, and the device lifetime LT95 is 141 hours @ initial luminance of 2000 cd / m². 2 .

[0170] The above embodiments demonstrate that the anthracene derivative based on the boron-nitrogen multiple resonance of the present invention has an extremely narrow half-width at half-maximum, which can effectively improve the color purity of the device. Furthermore, due to the introduction of the anthracene group with TTF effect, a synergistic effect between TTF and RISC is formed, thereby suppressing the quenching of triplet excitons. OLED devices fabricated based on the anthracene derivative of the boron-nitrogen multiple resonance of the present invention can achieve high device efficiency (EQE). max This results in lower drive voltage and longer device lifespan. Furthermore, longer device lifespan also reflects a decrease in roll-off (i.e., a smaller roll-off corresponds to a longer lifespan).

[0171] Appendix Figure 2 The external quantum efficiency-current density characteristic curves are shown for device examples 1, 4, 7, and 10. From the external quantum efficiency curves, it can be clearly concluded that the boron-nitrogen multiple resonance anthracene derivative described in this invention exhibits a high level of luminescence efficiency as a guest luminescent material, meeting the requirements for the industrial application of organic electroluminescent materials. (Appendix) Figure 3For the driving voltage comparison chart of device example 1, 4, 7, 10 and device comparative example 1, it can be seen that the OLED device prepared by the anthracene derivative with boron-nitrogen multiple resonance according to the present application has lower driving voltage than the conventional MR-TADF material, which meets the requirements of industrial application of organic electroluminescent material. Figure 4 For the device lifetime LT95 comparison chart of device example 1, 4, 7, 10 and device comparative example 1, it can be seen that the OLED device prepared by the anthracene derivative with boron-nitrogen multiple resonance according to the present application has more excellent device stability and lifetime than the conventional MR-TADF material, which meets the requirements of industrial application of organic electroluminescent material. Figure 5 For the device lifetime LT95 comparison chart of device example 13 to example 20 and device comparative example 1, it can be seen that when the anthracene derivative with boron-nitrogen multiple resonance according to the present application is used as the host light-emitting material or the mixed host light-emitting material, the stability and lifetime of the OLED device can be obviously improved, which meets the requirements of industrial application of organic electroluminescent material.

[0172] Those skilled in the art will easily understand that the above description is only the preferred embodiment of the present application, and is not intended to limit the present application, and any modification, equivalent replacement and improvement made within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims

1. An anthryl derivative based on a boron-nitrogen multiple resonance skeleton, characterized by, The anthracene derivative has a general formula structure as shown in at least one of general formulas A-1 to A-4: The R1 group is selected from: hydrogen, deuterium, methyl, tert-butyl, trifluoromethyl, phenyl, naphthyl, anthracene; The R2 group is selected from: hydrogen, deuterium, methyl, phenyl, methoxy, trifluoromethyl, tert-butyl, naphthyl, anthracene, halogen, pyrazinyl, pyridinyl, pyrimidinyl, benzimidazole cycloyl, indolecarbazoyl, carbazoyl, phenoxazinyl, phenothiazinyl, phenselenylazinyl, phenanzimidazole.

2. An anthracene derivative based on a boron-nitrogen multiple resonance framework, characterized in that, The anthracene derivative has a general formula structure as shown in at least one of general formulas A-1 to A-4: The R1 group is selected from: hydrogen, deuterium, methyl, tert-butyl, trifluoromethyl, phenyl, naphthyl, anthracene; The R2 group is selected from: C2~C 10 Straight-chain alkyl, C2~C 10 Branched alkyl, C7~C 30 Aryl, C2~C 10 Alkoxy, C1~C 10 Alkylamino, C2~C 10 Silyl group.

3. The anthracene derivative based on a boron-nitrogen multiple resonance framework as described in claim 1 or 2, characterized in that, The R1 group is hydrogen, methyl, trifluoromethyl, tert-butyl, or phenyl; The R2 group can be benzimidazole cycloyl, indolecarbazoyl, carbazoyl, phenoxazinyl, phenthiazinyl, phenselenyl, methyl, trifluoromethyl, tert-butyl, or phenyl.

4. The anthracene derivative based on a boron-nitrogen multiple resonance framework as described in claim 1 or 2, characterized in that, The structural formula of the anthracene derivative is shown in any one of Formulas 1 to 132: 。 5. The application of anthracene derivatives based on a boron-nitrogen multiple resonance framework as described in any one of claims 1-4 in the light-emitting layer of an organic electroluminescent device.

6. The application as described in claim 5, characterized in that, The organic electroluminescent device comprises, in sequence: an anode, a hole injection layer, a hole transport layer, a light-emitting layer, an electron transport layer, an electron injection layer, and a cathode.

7. The application as described in claim 6, characterized in that, An electron blocking layer or an exciton blocking layer is further disposed between the hole transport layer and the light-emitting layer; a hole blocking layer or an exciton blocking layer is further disposed between the light-emitting layer and the electron transport layer.

8. The application as described in claim 5, characterized in that, The anthracene derivatives based on the boron-nitrogen multi-resonance framework are specifically used as guest luminescent materials, host luminescent materials, or hybrid host luminescent materials in the luminescent layer of organic electroluminescent devices.

Images