An organic boron compound and its application in organic electroluminescent device

Abstract

The present invention relates to an organic boron compound and its application in an organic electroluminescent device, belonging to the technical field of optoelectronic materials. The compound is composed of a main body formed by bonding imidazopyridine with nitrogen groups such as aromatic amine, carbazole, and acridine, and the main center is modified by boron, and has a rigid large conjugated structure. Due to the bipolar imidazopyridine group regulating the electrical supply / acceptance of the compound, the HOMO of the compound is reduced. The device prepared by using the compound as a light-emitting layer material exhibits stable and efficient deep blue light emission, and has achieved significant progress in driving voltage, current efficiency, light color and life.

Description

Technical Field

[0001] The present invention relates to the field of optoelectronic materials, and in particular to an organic boron compound and application thereof in an organic electroluminescent device. Background Art

[0002] Organic light-emitting devices (OLEDs) include a cathode, an anode, and an organic layer between the two electrodes. The organic layer includes a multilayer structure such as a hole transport layer, an electron transport layer, and a light-emitting layer. Driven by an external electric field, holes and electrons are first injected from the anode and cathode respectively, then move toward each other in the hole transport layer and the electron transport layer, and then recombine into excitons in the light-emitting layer to emit various colors of light through radiative transition.

[0003] In order to apply OLED to full-color display, the realization of high-efficiency red, green and blue devices is the primary issue. At present, for green and red OLEDs, luminescent materials based on phosphorescence and thermally activated delayed fluorescence (TADF) mechanisms have achieved 100% internal quantum efficiency, and have been industrialized on a large scale and widely used in commercial full-color display devices. However, deep blue OLED materials for high-quality display have not achieved a major breakthrough. The blue material has a wide band gap, and the carrier transfer and energy transfer process in its electroluminescence process is difficult and unstable. In addition, the mutual quenching and deactivation phenomenon between excitons at high current density is very serious. Therefore, most deep blue devices will have very serious device efficiency roll-off and low brightness, and the service life is also very short.

[0004] In recent years, new π-conjugated organic unit materials containing boron and nitrogen co-embedded have become a research hotspot in blue light OLED material systems due to their good photophysical and electrochemical properties. Imidazole is a bipolar compound that is both acidic and alkaline. Its application in blue light OLED materials is of great significance for regulating the balance of carriers. Summary of the invention

[0005] The purpose of the present invention is to provide an organic boron compound and its application in an organic electroluminescent device, so as to improve the carrier transport balance of the current deep blue light emitting material, thereby making the deep blue light OLED device have excellent comprehensive performance in terms of luminous efficiency, stability, light color, life span, etc.

[0006] The first aspect of the present invention provides an organic boron compound, the general structure of which is shown in formula (1):

[0007]

[0008] in, are the same or different, and are independently represented by space, a single bond or -X0-, wherein X0 is selected from any one of O, S, N(R2) and C(R3)(R4);

[0009] Ar, Ar1 and Ar2 are the same as or different from each other, and are independently selected from any one of a benzene ring, a fused aromatic ring having no more than 18 carbon atoms, a fused aromatic heterocycle having no more than 18 carbon atoms, a benzene ring substituted by R1, a fused aromatic ring having no more than 18 carbon atoms substituted by R1, and a fused aromatic heterocycle having no more than 18 carbon atoms substituted by R1;

[0010] R0 is selected from hydrogen, fluoro, nitro, cyano, C 1-12 Alkyl, C 6-30 The aromatic group, C 3-30 The heteroaryl and C 6-30 Any one of the aromatic amine groups;

[0011] R1 is selected from hydrogen, fluoro, nitro, cyano, C 1-12 Alkyl, C 1-12 Alkoxy, C 3-12 Cycloalkyl, C 2-20 Heterocycloalkyl, C 6-30 The aromatic group, C 3-30 The heteroaryl and C 6-30 Any one of the aromatic amine groups;

[0012] R2-R4 are the same or different from each other and are independently selected from C 1-12 The alkyl and C 6-30 Any one of the aromatic groups.

[0013] Further, Ar, Ar1 and Ar2 are the same as or different from each other, and are independently selected from any one of the following: unsubstituted or R1-substituted benzene, unsubstituted or R1-substituted naphthalene, unsubstituted or R1-substituted dibenzofuran, unsubstituted or R1-substituted dibenzothiophene, unsubstituted or R1-substituted 9,9-dimethylfluorene, unsubstituted or R1-substituted carbazole, wherein the symbols and marks used have the meanings given in claim 1. That is, the definition of R1 is the same as R1 in the above chemical formula 1.

[0014] Further, when Ar, Ar1 and Ar2 are each independently benzene which is unsubstituted or substituted by R1, the organoboron compound is a compound represented by Formula 1-1:

[0015]

[0016] When Ar and Ar1 are each independently benzene that is unsubstituted or substituted by R1, and Ar2 is any one of naphthalene that is unsubstituted or substituted by R1, dibenzofuran that is unsubstituted or substituted by R1, dibenzothiophene that is unsubstituted or substituted by R1, 9,9-dimethylfluorene that is unsubstituted or substituted by R1, and carbazole that is unsubstituted or substituted by R1, the organoboron compound is a compound represented by Formula 1-2:

[0017]

[0018] When Ar is any one of unsubstituted or R1-substituted naphthalene, unsubstituted or R1-substituted dibenzofuran, unsubstituted or R1-substituted dibenzothiophene, unsubstituted or R1-substituted 9,9-dimethylfluorene, and unsubstituted or R1-substituted carbazole, and Ar2 is unsubstituted or R1-substituted benzene, the organoboron compound is a compound represented by Formula 1-3 or Formula 1-4:

[0019]

[0020] When Ar and Ar2 are each independently any one of unsubstituted or R1-substituted naphthalene, unsubstituted or R1-substituted dibenzofuran, unsubstituted or R1-substituted dibenzothiophene, unsubstituted or R1-substituted 9,9-dimethylfluorene, and unsubstituted or R1-substituted carbazole, the organoboron compound is a compound represented by Formula 1-5 or Formula 1-6:

[0021]

[0022] Wherein, the definitions of Ar1 and Ar2 are the same as those of Ar1 and Ar2 in claim 2.

[0023] The definition of same,

[0024] The definition of R0 is the same as R0 in the above formula 1,

[0025] The definition of R1 is the same as that of R1 in the above formula 1,

[0026] The definitions of R5, R6, and R7 are the same as those of R1 in the above formula 1.

[0027] Z is selected from any one of O, S, C(CH3)2, and N(Ph).

[0028] Furthermore, R2 is any one of unsubstituted or substituted phenyl groups with fluoro, nitro, cyano, methyl, and tert-butyl groups.

[0029] Furthermore, R3 and R4 are the same as each other and are both methyl groups.

[0030] Further, R1 is selected from any one of hydrogen, fluoro, nitro, cyano, methyl, tert-butyl, and phenyl which is unsubstituted or substituted by fluoro, nitro, cyano, methyl, tert-butyl, and phenyl.

[0031] Further, R0 is independently hydrogen, fluoro, nitro, cyano, methyl, tert-butyl, unsubstituted or substituted by fluoro, nitro, cyano, methyl, tert-butyl phenyl, biphenyl, the group shown in formula A1, the group shown in formula A2 and any one of the groups shown in formula A3:

[0032]

[0033] Wherein, X1 is selected from O, S, N(R8), C(R9)(R 10 ), R8-R 10 The same as or different from each other, and each independently selected from any one of methyl, unsubstituted or substituted phenyl with fluoro, nitro, cyano, methyl and tert-butyl.

[0034] Furthermore, the organoboron compound represented by Formula 1 is selected from any one of the following structural formulas:

[0035]

[0036]

[0037]

[0038]

[0039] The second aspect of the present invention provides an organic electroluminescent device, which mainly comprises a cathode, an anode and an organic layer located between the cathode and the anode, wherein the organic layer comprises any of the above-mentioned organic boron compounds.

[0040] Furthermore, the organic layer between the two electrodes includes a light-emitting layer, and the light-emitting layer contains any of the above-mentioned organic boron compounds.

[0041] The organoboron compound provided by the present invention is a donor-acceptor type main skeleton formed by bonding an imidazopyridine with a strong electron-deficient property with a nitrogen group with an electron-donating property such as an aromatic amine, carbazole, or acridine. The overall carrier mobility of the compound is more balanced, so a higher fluorescence quantum yield can be obtained. The main center is modified by boron to form a rigid large conjugated structure, so the HOMO of the compound is reduced to obtain a wider band gap, and stable deep blue light emission can be achieved. At the same time, better thermodynamic stability can also be obtained, and then it can be applied to organic electroluminescent devices, which have significant advantages in terms of the starting voltage, luminous efficiency and life of the device. DETAILED DESCRIPTION

[0042] It should be understood that the specific embodiments described herein are only used to illustrate and explain the present invention, and are not used to limit the present invention.

[0043] Synthesis Example 1: Synthesis of Compound (7)

[0044] S1: In a reactor, 3-bromoimidazo[1,2-a]pyridine (35 mmol, 6.90 g), 2,3-dichloro-5-fluoro-s-trimethylaniline (30 mmol, 8.95 g), sodium tert-butoxide (60 mmol, 5.76 g), trisdibenzylideneacetone dipalladium (0.15 mmol, 0.14 g), tri-tert-butylphosphine tetrafluoroborate (0.15 mmol, 0.04 g), and 100 mL of toluene were added, stirred and mixed thoroughly, and heated under nitrogen protection. The mixture was refluxed and the reaction was completed by monitoring the liquid phase. The mixture was cooled to room temperature, and diphenylamine (30 mmol, 5.08 g) was added. The mixture was stirred and mixed thoroughly. The mixture was heated and refluxed under nitrogen protection. The reaction was completed by monitoring the liquid phase. The mixture was cooled to room temperature. The reaction solution was extracted with a mixture of water and dichloromethane. The organic phase was dried over magnesium sulfate and concentrated. The mixture was purified and separated on a silica gel column using a mixed solvent of dichloromethane and petroleum ether in a ratio of 1:10 to obtain 10.18 g of the compound represented by the following chemical formula (7a). The yield was 62%.

[0045]

[0046] S2: In a reactor, the compound represented by the above (7a) (15 mmol, 8.21 g), 10-hydrogen-phenoxazine (20 mmol, 3.66 g), cesium carbonate (22.5 mmol, 7.33 g), and 100 mL of N,N-dimethylformamide were added, stirred and mixed thoroughly, and then heated under reflux under nitrogen protection for reaction. The reaction was completed when the liquid phase was monitored, and the mixture was cooled to room temperature. 50 mL-100 mL of water was added, and the mixture was filtered. The filtrate was extracted with dichloromethane twice and then concentrated. The mixture and the filter cake were slurried with ethanol twice to obtain 8.52 g of the compound represented by the following chemical formula (7b), with a yield of 80%;

[0047]

[0048] S3: In a reactor, the compound represented by (7b) (10 mmol, 7.10 g) was dissolved in 50 mL of tert-butylbenzene solution, the reaction solution was cooled to -40°C, 32.5 mL of 2.5 M n-hexane tert-butyl lithium solution was slowly added dropwise under nitrogen protection, the mixture was stirred for 0.5-2 h, boron tribromide (15 mmol, 3.76 g) was added, the reaction solution was heated to room temperature and stirred for 0.5-2 h, the reaction solution was cooled to 0°C, N,N-diisopropylethylamine (10 mmol, 1.29 g) was added, the mixture was heated to 120°C and refluxed for reaction, the reaction was completed by liquid phase monitoring, the mixture was cooled to room temperature, acetic acid was added to quench the reaction, the reaction solution was extracted with a mixture of water and dichloromethane, the organic phase was dried over magnesium sulfate and concentrated, and purified and separated on a silica gel column with a 1:10 mixed solvent of dichloromethane and petroleum ether to obtain 2.39 g of the compound represented by the following chemical formula (7), with a yield of 35%;

[0049]

[0050] The obtained compound was detected and analyzed, and the results were as follows: mass spectrometer MALDI-TOF-MS (m / z) was 683.6275; nuclear magnetic δ (ppm) = 9.02 (1H), 8.79 (1H), 8.45 (1H), 7.78 (2H), 7.70 (1H), 7.62 (1H), 7.47 (1H), 7.35 (2H), 7.22 (1H), 6.89-6.95 (4H) 6.77 (2H), 6.70 (1H), 6.59 (2H), 6.26 (1H), 6.02 (2H), 5.22 (2H), 2.20 (9H).

[0051] Synthesis Example 2: Synthesis of Compound (13)

[0052] S1: Replace 2,3-chloro-5-fluoro-trimethylaniline in S1 in Example 1 with 2,3-dichloro-N-diphenylamine (30 mmol, 7.14 g), and replace diphenylamine with 3,6-diphenyl-9-hydrogen-carbazole (30 mmol, 9.58 g). The other synthetic processes are the same as those in Example 1, and 11.09 g of the compound represented by the following chemical formula (13a) can be obtained with a yield of 58%;

[0053]

[0054] S2: The compound represented by (7b) in S3 of Example 1 was replaced by 6.37 g of the compound represented by (13a) above in this example. The other synthetic processes were the same as those of Example 1, and 1.89 g of the compound represented by the following chemical formula (13) was obtained, with a yield of 31%;

[0055]

[0056] The obtained compound was detected and analyzed, and the results were as follows: mass spectrometer MALDI-TOF-MS (m / z) was 610.5309; nuclear magnetic δ (ppm) = 9.05 (1H), 8.90 (1H), 8.76 (1H), 8.45 (1H), 8.22 (1H), 8.06 (1H), 7.95 (1H), 7.81-7.87 (4H), 7.72 (2H), 7.62 (3H), 7.48 (2H), 7.32 (2H), 7.20 (2H), 7.05 (1H), 6.73 (1H), 6.25 (1H), 6.14 (2H).

[0057] Synthesis Example 3: Synthesis of Compound (26)

[0058] S1: Replace 2,3-chloro-5-fluoro-trimethylaniline in S1 in Example 1 with N-(2,3-dichlorophenyl)-[1,1'-biphenyl]-4-amine (30 mmol, 9.43 g), and replace diphenylamine with 5-(p-methylphenyl)-5,10-dihydrophenazine (30 mmol, 8.17 g). The other synthetic processes are the same as those in Example 1, and 12.79 g of the compound represented by the following chemical formula (26a) can be obtained with a yield of 64%;

[0059]

[0060] S2: The compound represented by (7b) in S3 of Example 1 was replaced by 6.66 g of the compound represented by (26a) above in this example. The other synthetic processes were the same as those of Example 1, and 2.11 g of the compound represented by the following chemical formula (26) was obtained, with a yield of 33%;

[0061]

[0062] The obtained compound was detected and analyzed, and the results were as follows: mass spectrometer MALDI-TOF-MS (m / z) was 639.5615; nuclear magnetic δ (ppm) = 9.03 (1H), 8.42 (1H), 8.11 (1H), 7.78 (2H), 7.71 (1H), 7.63 (1H), 7.55 (2H), 7.48 (2H), 7.40 (1H), 7.32 (2H), 7.27 (1H), 7.21 (2H), 7.16 (1H), 6.97-7.03 (5H), 6.89 (1H), 6.26 (1H), 6.14 (2H), 2.26 (3H).

[0063] Synthesis Example 4: Synthesis of Compound (28)

[0064] S1: The diphenylamine in S1 in Example 1 was replaced with 10-hydrogen-phenothiazine (30 mmol, 5.98 g), and the other synthetic processes were the same as in Example 1 to obtain 10.39 g of the compound represented by the following chemical formula (28a), with a yield of 60%;

[0065]

[0066] S2: Replace (7a) in S2 in Example 1 with 8.66 g of the compound represented by (28a) in this example, and replace 10-hydrogen-phenoxazine with 9-hydrogen-carbazole (20 mmol, 3.34 g). The other synthetic processes are the same as those in Example 1, to obtain 9.02 g of the compound represented by the following chemical formula (28b), with a yield of 83%;

[0067]

[0068] S3: The compound represented by (7b) in S3 of Example 1 was replaced by 7.24 g of the compound represented by (28b) in this example. The rest of the synthesis process was the same as that of Example 1, and 2.52 g of the compound represented by the following chemical formula (28) was obtained, with a yield of 36%;

[0069]

[0070] The obtained compound was detected and analyzed, and the results were as follows: mass spectrometer MALDI-TOF-MS (m / z) was 697.6698; nuclear magnetic δ (ppm) = 9.10 (1H), 8.47 (1H), 8.18 (2H), 7.95 (1H), 7.83 (1H), 7.75 (2H), 7.64 (1H), 7.50 (2H), 7.21 (3H), 7.12 (1H), 7.00 (1H), 6.87-6.94 (4H), 6.80 (2H), 6.31 (1H), 2.20 (9H).

[0071] Synthesis Example 5: Synthesis of Compound (33)

[0072] S1: Replace 2,3-chloro-5-fluoro-s-trimethylaniline in S1 in Example 1 with 2-chloro-9-hydrogen-carbazole (30 mmol, 6.05 g), and replace diphenylamine with 4,4'-dicyanodiphenylamine (30 mmol, 6.58 g). The other synthetic processes are the same as those in Example 1, and 8.56 g of the compound represented by the following chemical formula (33a) can be obtained with a yield of 57%;

[0073]

[0074] S2: Substitute the compound represented by (7b) in S3 of Example 1 with 5.01 g of the compound represented by (33a) above in this example, and carry out the other synthetic processes in the same manner as in Example 1 to obtain 1.73 g of the compound represented by the following chemical formula (33), with a yield of 34%;

[0075]

[0076] The obtained compound was detected and analyzed, and the results were as follows: mass spectrometer MALDI-TOF-MS (m / z) was 508.3561.

[0077] Synthesis Example 6: Synthesis of Compound (39)

[0078] S1: Replace 2,3-chloro-5-fluoro-trimethylaniline in S1 in Example 1 with 2-chloro-10-hydrogen-phenothiazine (30 mmol, 7.01 g), and replace diphenylamine with di(4-(tert-butyl)phenyl)amine (30 mmol, 8.44 g). The other synthetic processes are the same as those in Example 1, to obtain 10.53 g of the compound represented by the following chemical formula (39a), with a yield of 59%;

[0079]

[0080] S2: Substitute the compound represented by (7b) in S3 of Example 1 with 5.95 g of the compound represented by (39a) above in this example, and carry out the other synthetic processes in the same manner as in Example 1 to obtain 1.87 g of the compound represented by the following chemical formula (39), with a yield of 31%;

[0081]

[0082] The obtained compound was detected and analyzed, and the results were as follows: mass spectrometer MALDI-TOF-MS (m / z) was 602.6023.

[0083] Synthesis Example 7: Synthesis of Compound (46)

[0084] S1: Replace 2,3-chloro-5-fluoro-s-trimethylaniline in S1 in Example 1 with 2-chloro-9-hydrogen-carbazole (30 mmol, 6.05 g), replace 3-bromoimidazo[1,2-a]pyridine with 3-bromo-7-phenylimidazo[1,2-a]pyridine (35 mmol, 9.56 g), and replace diphenylamine with 9-hydrogen-carbazole (30 mmol, 5.02 g). The other synthetic processes are the same as those in Example 1, and 9.60 g of the compound represented by the following chemical formula (46a) can be obtained, with a yield of 61%;

[0085]

[0086] S2: Substitute the compound represented by (7b) in S3 of Example 1 with 5.25 g of the compound represented by (46a) above in this example, and carry out the other synthetic processes in the same manner as in Example 1 to obtain 1.86 g of the compound represented by the following chemical formula (46), with a yield of 35%;

[0087]

[0088] The obtained compound was detected and analyzed, and the results were as follows: mass spectrometer MALDI-TOF-MS (m / z) was 532.4167.

[0089] Synthesis Example 8: Synthesis of Compound (49)

[0090] S1: Replace 2,3-chloro-5-fluoro-s-trimethylaniline in S1 in Example 1 with 2-chloro-9-hydro-carbazole (30 mmol, 6.05 g), and replace diphenylamine with 9,9-dimethyl-9,10-dihydroacridine (30 mmol, 6.28 g). The other synthetic processes are the same as those in Example 1, and 9.57 g of the compound represented by the following chemical formula (49a) can be obtained with a yield of 65%;

[0091]

[0092] S2: The compound represented by (7b) in S3 of Example 1 was replaced by 4.91 g of the compound represented by (49a) above in this example. The rest of the synthesis process was the same as that of Example 1, and 1.84 g of the compound represented by the following chemical formula (49) was obtained, with a yield of 37%;

[0093]

[0094] The obtained compound was detected and analyzed, and the results were as follows: mass spectrometer MALDI-TOF-MS (m / z) was 498.3928.

[0095] Synthesis Example 9: Synthesis of Compound (52)

[0096] S1: Replace 2,3-chloro-5-fluoro-s-trimethylaniline in S1 in Example 1 with 2-chloro-10-hydrogen-phenoxazine (30 mmol, 6.53 g), and replace diphenylamine with 10-hydrogen-phenoxazine (30 mmol, 5.50 g). The other synthetic processes are the same as those in Example 1, to obtain 9.08 g of the compound represented by the following chemical formula (52a), with a yield of 63%;

[0097]

[0098] S2: The compound represented by (7b) in S3 of Example 1 was replaced by 4.81 g of the compound represented by (52a) in this example. The rest of the synthesis process was the same as that of Example 1, and 1.66 g of the compound represented by the following chemical formula (52) was obtained, with a yield of 34%;

[0099]

[0100] The obtained compound was detected and analyzed, and the results were as follows: mass spectrometer MALDI-TOF-MS (m / z) was 488.3175.

[0101] Synthesis Example 10: Synthesis of Compound (58)

[0102] S1: Replace 2,3-chloro-5-fluoro-s-trimethylaniline in S1 in Example 1 with 2-chloro-5-phenyl-5,10-dihydrophenazine (30 mmol, 8.78 g), and replace diphenylamine with 3,6-difluoro-9-hydrogen-carbazole (30 mmol, 6.10 g). The other synthetic processes are the same as those in Example 1, and 10.36 g of the compound represented by the following chemical formula (58a) can be obtained with a yield of 60%;

[0103]

[0104] S2: Substitute the compound represented by (7b) in S3 of Example 1 with 5.76 g of the compound represented by (58a) of this example. The rest of the synthesis process is the same as that of Example 1 to obtain 1.87 g of the compound represented by the following chemical formula (58), with a yield of 32%;

[0105]

[0106] The obtained compound was detected and analyzed, and the results were as follows: mass spectrometer MALDI-TOF-MS (m / z) was 583.4043.

[0107] Synthesis Example 11: Synthesis of Compound (65)

[0108] S1: Replace 2,3-chloro-5-fluoro-s-trimethylaniline in S1 in Example 1 with (2,3-dichloro-5-fluorophenyl)naphthalene-2-amine (30 mmol, 9.18 g), and replace diphenylamine with 9-hydrogen-carbazole (30 mmol, 5.02 g). The other synthetic processes are the same as those in Example 1, to obtain 9.13 g of the compound represented by the following chemical formula (65a), with a yield of 55%;

[0109]

[0110] S2: Replace (7a) in S2 in Example 1 with 8.30 g of the compound represented by (65a) in this example, and replace 10-hydrogen-phenoxazine with diphenylamine (20 mmol, 3.38 g). The other synthetic processes are the same as those in Example 1, and the compound g represented by the following chemical formula (65b) can be obtained with a yield of 81%;

[0111]

[0112] S3: Substitute the compound represented by (7b) in S3 of Example 1 with 7.02 g of the compound represented by (65b) above in this example, and carry out the other synthetic processes in the same manner as in Example 1 to obtain 2.50 g of the compound represented by the following chemical formula (65), with a yield of 37%;

[0113]

[0114] The obtained compound was detected and analyzed, and the results were as follows: mass spectrometer MALDI-TOF-MS (m / z) was 675.6066; nuclear magnetic δ (ppm) = 9.04 (1H), 8.67 (1H), 8.47 (1H), 8.18 (1H), 7.98 (2H), 7.87 (1H), 7.70 (1H), 7.60 (1H), 7.47-7.54 (6H), 7.41 (1H), 7.38 (1H), 7.33 (1H), 7.20 (1H), 7.11 (5H), 7.01 (1H), 6.94 (2H), 6.25 (1H), 5.22 (2H).

[0115] Synthesis Example 12: Synthesis of Compound (70)

[0116] S1: Replace 2,3-chloro-5-fluoro-s-trimethylaniline in S1 in Example 1 with N-(2,3-dichloro-5-nitrophenyl)-9,9-dimethyl-9-hydrogen-fluorene-2-amine (30 mmol, 11.98 g), and replace diphenylamine with 10-hydrogen-phenothiazine (30 mmol, 5.98 g). The other synthetic processes are the same as those in Example 1, and 11.80 g of the compound represented by the following chemical formula (70a) is obtained, with a yield of 58%;

[0117]

[0118] S2: The compound represented by (7b) in S3 of Example 1 was replaced by 6.78 g of the compound represented by (70a) in this example. The rest of the synthesis process was the same as that of Example 1, and 2.28 g of the compound represented by the following chemical formula (70) was obtained with a yield of 35%;

[0119]

[0120] The obtained compound was detected and analyzed, and the results were as follows: mass spectrometer MALDI-TOF-MS (m / z) was 651.5478; nuclear magnetic δ (ppm) = 9.02 (1H), 8.43 (1H), 8.19 (1H), 8.04 (2H), 7.98 (1H), 7.87 (2H), 7.75 (1H), 7.63 (1H), 7.51 (1H), 7.44 (1H), 7.38 (1H), 7.12-7.21 (3H), 7.02 (2H), 6.91 (1H), 6.25 (1H), 1.79 (6H).

[0121] Synthesis Example 13: Synthesis of Compound (73)

[0122] S1: Replace 2,3-chloro-5-fluoro-trimethylaniline in S1 in Example 1 with N-(2,3-dichlorophenyl)-2,4,6-trimethylamine (30 mmol, 8.41 g), and replace diphenylamine with N-(4-(tert-butyl)phenyl)dibenzofuran-2-amine (30 mmol, 9.46 g). The other synthetic processes are the same as those in Example 1, and 10.74 g of the compound represented by the following chemical formula (73a) can be obtained with a yield of 53%;

[0123]

[0124] S2: The compound represented by (7b) in S3 of Example 1 was replaced by 6.75 g of the compound represented by (73a) above in this example. The rest of the synthesis process was the same as that of Example 1, and 2.47 g of the compound represented by the following chemical formula (73) was obtained with a yield of 38%;

[0125]

[0126] The obtained compound was detected and analyzed, and the results were as follows: mass spectrometer MALDI-TOF-MS (m / z) was 648.6126; nuclear magnetic δ (ppm) = 9.06 (1H), 8.45 (1H), 8.33 (1H), 8.05 (1H), 7.74 (1H), 7.61 (1H), 7.63 (1H), 7.43-7.51 (3H), 7.36 (1H), 7.25 (1H), 7.13 (2H), 6.95 (2H), 6.23 (1H), 6.14 (2H), 2.20 (9H), 1.35 (9H).

[0127] Synthesis Example 14: Synthesis of Compound (80)

[0128] S1: Replace 2,3-chloro-5-fluoro-trimethylaniline in S1 in Example 1 with 2-chloro-10-hydrogen-phenoxazine (30 mmol, 6.53 g), and replace diphenylamine with nitrogen-(2,5-dimethyl-[1,1'-biphenyl]-4-yl)naphthalene-2-amine (30 mmol, 9.70 g). The other synthetic processes are the same as those in Example 1, and 10.61 g of the compound represented by the following chemical formula (80a) is obtained, with a yield of 57%;

[0129]

[0130] S2: The compound represented by (7b) in S3 of Example 1 was replaced by 6.21 g of the compound represented by (80a) in this example. The rest of the synthesis process was the same as that of Example 1, and 2.08 g of the compound represented by the following chemical formula (80) was obtained, with a yield of 33%;

[0131]

[0132] The obtained compound was detected and analyzed, and the results were as follows: mass spectrometer MALDI-TOF-MS (m / z) was 628.5389; nuclear magnetic δ (ppm) = 9.02 (1H), 8.48 (1H), 7.84 (1H), 7.79 (1H), 7.70 (1H), 7.64 (1H), 7.54 (2H), 7.38-7.47 (4H), 7.30 (2H), 7.21 (3H), 7.15 (1H), 7.06 (1H), 6.98 (1H), 6.85 (1H), 6.77 (1H), 6.26 (1H), 2.47 (3H), 2.19 (3H).

[0133] Synthesis Example 15: Synthesis of Compound (81)

[0134] The 2,3-dichloro-5-(10-hydrogen-phenoxazine-10-yl)-N-diphenylamine in Example 1 was replaced by N-(2,3-dichlorophenyl)naphthalene-2-amine (30 mmol, 8.65 g), and the diphenylamine was replaced by 2,2-dinaphthylamine (30 mmol, 8.08 g). The other synthetic processes were the same as those in Example 1, and 11.28 g of the compound represented by the following chemical formula (81a) was obtained with a yield of 59%;

[0135]

[0136] The compound represented by (7a) in Example 1 was replaced by 6.37 g of the compound represented by (81a) in this example. The rest of the synthesis process was the same as in Example 1 to obtain 2.32 g of the compound represented by the following chemical formula (81), with a yield of 38%;

[0137]

[0138] The obtained compound was detected and analyzed, and the results were as follows: mass spectrometer MALDI-TOF-MS (m / z) was 610.5306; nuclear magnetic δ (ppm) = 9.03 (1H), 8.44 (1H), 7.75-7.87 (6H), 7.61 (1H), 7.54 (2H), 7.49 (3H), 7.43 (3H), 7.38 (2H), 7.31 (1H), 7.26 (1H), 7.06 (1H), 7.01 (2H), 6.25 (1H), 6.14 (2H).

[0139] Device Example 1

[0140] The glass substrate with a 50nm ITO transparent film was ultrasonically cleaned with acetone, isopropanol and deionized water for 10 minutes each, vacuum dried at 105°C for 2 hours, and then UV ozone washed for 15 minutes, and then the ITO glass substrate was transferred to a vacuum evaporator.

[0141] On the surface on which the ITO film is formed, 4,4',4"-tri[2-naphthyl(phenyl)amino]triphenylamine (2T-NATA) is vacuum-deposited to form a hole injection layer with a thickness of 80 nm;

[0142] Next, N,N'-diphenyl-N,N'-(1-naphthyl)-1,1'-biphenyl-4,4'-diamine (NPB) was vacuum-deposited on the hole injection layer to form a 30 nm thick hole transport layer.

[0143] Next, on the hole transport layer, the compound 7 prepared in the above-mentioned Synthesis Example 1 was vacuum-deposited to form a light-emitting layer with a thickness of 30 nm;

[0144] Next, on the light-emitting layer, bis(2-methyl-8-hydroxyquinoline-N1,O8)-(1,1'-biphenyl-4-hydroxy)aluminum (BAlq) was vacuum-deposited to form a hole blocking layer with a thickness of 10 nm;

[0145] Next, 8-hydroxyquinoline aluminum (Alq3) is vacuum-deposited on the hole blocking layer to form an electron transport layer with a thickness of 20 nm;

[0146] Finally, aluminum (Al) was vacuum-evaporated on the electron transport layer to form a cathode with a thickness of 100 nm.

[0147] Device Example 2 to Device Example 15

[0148] An organic electroluminescent device was prepared in the same manner as in Device Example 1, except that the compounds synthesized in Synthesis Example 2 to Synthesis Example 15 were used to replace Compound 7 prepared in Synthesis Example 1.

[0149] The performance of the organic electroluminescent devices prepared in the above device embodiments was tested, and the results are shown in Table 1:

[0150] Table 1

[0151]

[0152]

[0153] It can be seen from the data in Table 1 above that the compound provided by the present invention, which is composed of a main body formed by ring nitrogen bonding of imidazopyridine and aromatic amine, carbazole, acridine and other groups, and the main center is modified by boron, has a rigid large conjugated structure, and the bipolar imidazopyridine group can adjust the charge-giving and charge-accepting properties of the compound, and at the same time reduce the HOMO of the compound, so that the compound material can achieve stable and efficient deep blue light emission. The organic electroluminescent device prepared using the compound of the present invention as the light-emitting layer material is simple and efficient to prepare, and has achieved significant progress in driving voltage, current efficiency, light color and life.

[0154] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. An organic boron compound, characterized in that The general structure of the compound is shown in Formula 1: in, Different, each independently represents a space or a single bond or -X0-, wherein X0 is selected from any one of O, S, N(R2) and C(R3)(R4); Ar, Ar1 and Ar2 are the same as or different from each other, and are independently selected from any one of the following: unsubstituted or R1-substituted benzene, unsubstituted or R1-substituted naphthalene, unsubstituted or R1-substituted dibenzofuran, unsubstituted or R1-substituted dibenzothiophene, unsubstituted or R1-substituted 9,9-dimethylfluorene, unsubstituted or R1-substituted carbazole; R0 is selected from hydrogen, fluoro, nitro, cyano, C 1-12 Alkyl, C 6-30 The aromatic group, C 3-30 The heteroaryl and C 6-30 Any one of the aromatic amine groups; R1 is selected from hydrogen, fluoro, nitro, cyano, C 1-12 Alkyl, C 6-30 Any one of the aromatic groups; R2-R4 are the same or different from each other and are independently selected from C 1-12 The alkyl and C 6-30 Any one of the aromatic groups.

2. The organoboron compound according to claim 1, characterized in that When Ar, Ar1, and Ar2 are each independently benzene that is unsubstituted or substituted by R1, the organoboron compound is a compound represented by Formula 1-1: When Ar and Ar1 are each independently benzene that is unsubstituted or substituted by R1, and Ar2 is any one of naphthalene that is unsubstituted or substituted by R1, dibenzofuran that is unsubstituted or substituted by R1, dibenzothiophene that is unsubstituted or substituted by R1, 9,9-dimethylfluorene that is unsubstituted or substituted by R1, and carbazole that is unsubstituted or substituted by R1, the organoboron compound is a compound represented by Formula 1-2: When Ar is any one of unsubstituted or R1-substituted naphthalene, unsubstituted or R1-substituted dibenzofuran, unsubstituted or R1-substituted dibenzothiophene, unsubstituted or R1-substituted 9,9-dimethylfluorene, and unsubstituted or R1-substituted carbazole, and Ar2 is unsubstituted or R1-substituted benzene, the organoboron compound is a compound represented by Formula 1-3 or Formula 1-4: When Ar and Ar2 are each independently any one of unsubstituted or R1-substituted naphthalene, unsubstituted or R1-substituted dibenzofuran, unsubstituted or R1-substituted dibenzothiophene, unsubstituted or R1-substituted 9,9-dimethylfluorene, and unsubstituted or R1-substituted carbazole, the organoboron compound is a compound represented by Formula 1-5 or Formula 1-6: Wherein, the definitions of Ar1 and Ar2 are the same as those of Ar1 and Ar2 in claim 1. The definition of The same, R0 is defined the same as R0 in the above formula 1, The definition of R1 is the same as that of R1 in the above formula 1, The definitions of R5, R6, and R7 are the same as those of R1 in the above formula 1. Z is selected from any one of O, S, C(CH3)2, and N(Ph).

3. The organoboron compound according to claim 1, characterized in that The R2 is any one of unsubstituted or substituted phenyl groups with fluoro, nitro, cyano, methyl and tert-butyl groups.

4. The organoboron compound according to claim 1, characterized in that The R3 and R4 are the same as each other and are both methyl groups.

5. The organoboron compound according to claim 1, characterized in that The R1 is selected from any one of hydrogen, fluoro, nitro, cyano, methyl, tert-butyl, unsubstituted or substituted phenyl by fluoro, nitro, cyano, methyl, tert-butyl, and phenyl.

6. The organoboron compound according to claim 1, characterized in that The R0 is independently hydrogen, fluoro, nitro, cyano, methyl, tert-butyl, unsubstituted or substituted phenyl, biphenyl, a group shown in formula A1, a group shown in formula A2, and any one of a group shown in formula A3: Wherein, X1 is selected from O, S, N(R8), C(R9)(R 10 ), R8-R 10 The same as or different from each other, and each independently selected from any one of methyl, unsubstituted or substituted phenyl with fluoro, nitro, cyano, methyl and tert-butyl.

7. The organoboron compound according to claim 1, characterized in that The organoboron compound is selected from any one of the following structural formulas:

8. An organic electroluminescent device comprising a cathode, an anode, and an organic layer located between the cathode and the anode, characterized in that: The organic layer comprises the organic boron compound according to any one of claims 1 to 7.

9. The organic electroluminescent device according to claim 8, characterized in that: The organic layer comprises a light-emitting layer, and the light-emitting layer comprises the organic boron compound according to any one of claims 1-7.

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