阅读说明：本技术 一种有机化合物及其应用及采用该化合物的有机电致发光器 (Organic compound, application thereof and organic electroluminescent device adopting organic compound ) 是由 段炼 张东东 黄天宇 于 2020-11-20 设计创作，主要内容包括：本发明涉及有机电致发光技术领域,特别涉及一种有机化合物及其应用以及包含该化合物的有机电致发光器件,具体涉及一种新型热活化延迟荧光材料,具有如下式(1)的结构,D_1～D_4独立地选自氘、取代或未取代的C3～C60的单环杂芳基、取代或未取代的C3～C60的稠环杂芳基中的一种,A选自取代或未取代的C3～C60且至少含有一个氮原子的单环杂芳基、取代或未取代的C3～C60且至少含有一个氮原子的稠环杂芳基中的一种,R选自取代或未取代的C6～C30芳基、取代或未取代的C3～C30单环杂芳基、取代或未取代的C3～C30稠环杂芳基中的一种。本发明的化合物用作OLED器件中的发光层材料时,具有更高的光致发光量子效率,更快的反向系间窜跃速率,能表现出优异的器件效率和稳定性。本发明同时保护采用上述通式化合物的有机电致发光器件。(The invention relates to the technical field of organic electroluminescence, in particular to an organic compound, application thereof and an organic electroluminescent device containing the compound, and specifically relates to a novel thermal activation delayed fluorescent material which has a structure shown in the following formula (1), D 1 ～D 4 Independently selected from deuterium, substituted or unsubstituted monocyclic heteroaryl of C3-C60, and substituted or unsubstituted fused ring heteroaryl of C3-C60, A is selected from substituted or unsubstituted monocyclic heteroaryl of C3-C60 containing at least one nitrogen atom, substituted or unsubstituted fused ring heteroaryl of C3-C60 containing at least one nitrogen atom, and R is selected from substituted or unsubstituted C6-C30 aryl, substituted or unsubstituted C3-C30 monocyclic heteroaryl, and substituted or unsubstituted C3-C30 fused ring heteroaryl. When the compound is used as a light-emitting layer material in an OLED device, the compound has higher photoluminescence quantum efficiency and faster reverse system cross-over rate, and can show excellent device efficiency and stability. The invention also protects the organic electroluminescent device adopting the compound with the general formula.)

1. An organic compound having a structure represented by the following formula (1):

in the formula (1), D₁～D₄Independently selected from deuterium, substituted or unsubstituted monocyclic heteroaryl of C3-C60, substituted or unsubstituted fused ring heteroaryl of C3-C60;

in formula (1), A is selected from one of substituted or unsubstituted monocyclic heteroaryl group containing C3-C60 and at least one nitrogen atom, substituted or unsubstituted fused ring heteroaryl group containing C3-C60 and at least one nitrogen atom, or a substituent group selected from the following structures:

NC-＊ NC-Ar₁-＊

wherein Ar is₁、Ar₂、Ar₃、Ar₄And Ar₅Each independently selected from one of a substituted or unsubstituted monocyclic aryl group of C6-C60 and a substituted or unsubstituted fused ring aryl group of C6-C60;

in the formula (1), R is selected from one of substituted or unsubstituted C6-C30 aryl, substituted or unsubstituted C3-C30 monocyclic heteroaryl, substituted or unsubstituted C3-C30 fused ring heteroaryl, or is selected from a substituent group with the following structure:

NC-＊ NC-Ar₁-＊

wherein Ar is₁、Ar₂、Ar₃、Ar₄And Ar₅Each independently selected from one of substituted or unsubstituted C6-C60 monocyclic aryl and substituted or unsubstituted C6-C60 condensed ring aryl, R₁、R₂、R₃And R₄Each independently selected from the group consisting of C1-C30 alkyl, C6-C60 aryl, and when R is selected from the group consisting of substituted or unsubstituted C3-C30 monocyclic heteroaryl, substituted or unsubstituted C3-C30 fused ring heteroaryl, the heteroatoms in the monocyclic heteroaryl and fused ring heteroaryl may further include an oxygen atom, a sulfur atom, or a selenium atom;

when the substituent exists on the substituent group, the substituent group is selected from one or more of C1-C30 chain alkyl, C3-C30 naphthenic base, C1-C6 alkoxy, C6-C30 aryl and C3-C60 heteroaryl.

2. The organic compound of claim 1, said D₁～D₄Independently selected from deuterium, a substituted or unsubstituted monocyclic heteroaryl group of C3-C60 containing at least one nitrogen atom, a substituted or unsubstituted fused ring heteroaryl group of C3-C60 containing at least one nitrogen atom;

preferably, the heteroatoms in the monocyclic heteroaryl and fused ring heteroaryl further include an oxygen atom, a sulfur atom, or a selenium atom.

3. The organic compound of claim 1, said D₁～D₄Independently selected from deuterium, substituted or unsubstituted carbazolyl, substituted or unsubstituted pyridyl, substituted or unsubstituted imidazolyl, substituted or unsubstituted triazinyl, substituted or unsubstituted furyl, and substituted or unsubstituted thienyl;

when the above D is₁～D₄When the substituent exists, the substituent is selected from one or more of C1-C30 chain alkyl, C3-C30 cycloalkyl, C1-C6 alkoxy, C6-C30 aryl and C3-C60 heteroaryl.

4. The organic compound of claim 1, said D₁～D₄Independently selected from one of the following substituent groups: deuterium, furyl, benzofuryl, isobenzofuryl, dibenzofuryl, thienyl, benzothienyl, isobenzothienyl, dibenzothienyl, pyrrolyl, isoindoleIndole, carbazolyl, indenocarbazolyl, pyridyl, quinolyl, isoquinolyl, acridinyl, phenanthridinyl, benzo-5, 6-quinolyl, benzo-6, 7-quinolyl, benzo-7, 8-quinolyl, pyrazolyl, indazolyl, imidazolyl, benzimidazolyl, naphthoimidazolyl, phenanthroimidazolyl, pyridoimidazolyl, pyrazinoimidazolyl, quinoxalimidazolyl, oxazolyl, benzoxazolyl, naphthooxazolyl, anthraoxazolyl, phenanthroizolyl, 1, 2-thiazolyl, 1, 3-thiazolyl, benzothiazolyl, pyridazinyl, benzopyrazinyl, pyrimidinyl, benzopyrimidinyl, quinoxalinyl, 1, 5-diazaanthrenyl, 2, 7-diazapyryl, 2, 3-diazapyryl, 1, 6-diazapyryl, 1, 8-diazenyl, 4,5,9, 10-tetraazaperyl, pyrazinyl, phenazinyl, phenothiazinyl, naphthyridinyl, azacarbazolyl, benzocarbazinyl, phenanthrolinyl, 1,2, 3-triazolyl, 1,2, 4-triazolyl, benzotriazolyl, 1,2, 3-oxadiazolyl, 1,2, 4-oxadiazolyl, 1,2, 5-oxadiazolyl, 1,2, 3-thiadiazolyl, 1,2, 4-thiadiazolyl, 1,2, 5-thiadiazolyl, 1,3, 4-thiadiazolyl, 1,3, 5-triazinyl, 1,2, 4-triazinyl, 1,2, 3-triazinyl, tetrazolyl, 1,2,4, 5-tetrazinyl, 1,2,3, 4-tetrazinyl, 1,2,3, 5-tetrazinyl, purinyl, pteridinyl, indolizinyl, benzothiadiazolyl, 9-dimethylazinyl, or a combination selected from the two above.

5. The organic compound according to claim 1, formula (1), wherein D is₁～D₄Each independently selected from deuterium or from a group represented by the structure:

and represents the position of the bond of the substituent group.

6. The organic compound according to claim 1, wherein in formula (1), a is selected from the group represented by the following structures:

7. the organic compound according to claim 1, wherein R in formula (1) is selected from the group represented by the following structures:

8. the organic compound according to claim 1, selected from the following compounds of specific structure:

9. use of a compound according to any one of claims 1 to 8 as a functional material in an organic electronic device comprising an organic electroluminescent device, an optical sensor, a solar cell, a lighting element, an organic thin film transistor, an organic field effect transistor, an organic thin film solar cell, an information label, an electronic artificial skin sheet, a sheet-type scanner or electronic paper;

further, the compound is applied to be used as a luminescent layer material in an organic electroluminescent device, and is particularly used as luminescent dye of a luminescent layer.

10. An organic electroluminescent device comprising a first electrode, a second electrode and one or more light-emitting functional layers interposed between the first electrode and the second electrode, wherein the light-emitting functional layers contain the compound according to any one of claims 1 to 8;

furthermore, the light-emitting functional layer comprises a hole transport region, a light-emitting layer and an electron transport region, wherein the hole transport region is formed on the anode layer, the cathode layer is formed on the electron transport region, and the light-emitting layer is arranged between the hole transport region and the electron transport region; wherein the light-emitting layer contains the compound according to any one of claims 1 to 8.

Technical Field

The invention relates to the technical field of organic electroluminescence, in particular to an organic compound, application thereof and an organic electroluminescent device containing the compound, and specifically relates to a thermal activation delayed fluorescent material.

Background

Organic Light Emission Diodes (OLED) are a kind of devices with sandwich-like structure, which includes positive and negative electrode films and Organic functional material layers sandwiched between the electrode films. And applying voltage to the electrodes of the OLED device, injecting positive charges from the positive electrode and injecting negative charges from the negative electrode, and transferring the positive charges and the negative charges in the organic layer under the action of an electric field to meet for composite luminescence. Because the OLED device has the advantages of high brightness, fast response, wide viewing angle, simple process, flexibility and the like, the OLED device is concerned in the field of novel display technology and novel illumination technology. At present, the technology is widely applied to display panels of products such as novel lighting lamps, smart phones and tablet computers, and further expands the application field of large-size display products such as televisions, and is a novel display technology with fast development and high technical requirements.

With the continuous advance of OLEDs in both lighting and display areas, much attention has been paid to the research on their core materials. This is because an efficient, long-lived OLED device is generally the result of an optimized configuration of the device structure and various organic materials, which provides great opportunities and challenges for chemists to design and develop functional materials with various structures. Common functionalized organic materials are: hole injection materials, hole transport materials, hole blocking materials, electron injection materials, electron transport materials, electron blocking materials, and light emitting host materials and light emitting objects (dyes), and the like.

In order to prepare an OLED light-emitting device with lower driving voltage, better light-emitting efficiency and longer service life, the performance of the OLED device is continuously improved, the structure and the manufacturing process of the OLED device need to be innovated, and photoelectric functional materials in the OLED device need to be continuously researched and innovated, so that functional materials with higher performance can be prepared. Based on this, the OLED material industry has been working on developing new organic electroluminescent materials to achieve low lighting voltage, high luminous efficiency and better lifetime of the device.

Disclosure of Invention

In order to solve the technical problems, the invention provides an organic compound, in particular to a novel thermal activation delayed fluorescent material which can be applied to the field of organic electroluminescence.

The organic compound of the present invention has a structure represented by the following formula (1):

in the formula (1), D₁～D₄Independently selected from deuterium, substituted or unsubstituted monocyclic heteroaryl of C3-C60, substituted or unsubstituted fused ring heteroaryl of C3-C60;

preferably, D₁～D₄Independently selected from deuterium, substituted or unsubstituted C3-C60And at least one nitrogen atom-containing monocyclic heteroaryl group, or a substituted or unsubstituted fused ring heteroaryl group having C3-C60 and at least one nitrogen atom; further, the hetero atom in the monocyclic heteroaryl group and the fused ring heteroaryl group may further include an oxygen atom, a sulfur atom, or a selenium atom.

Further preferably, D₁～D₄Independently selected from deuterium, substituted or unsubstituted carbazolyl, substituted or unsubstituted pyridyl, substituted or unsubstituted imidazolyl, substituted or unsubstituted triazinyl, substituted or unsubstituted furyl, and substituted or unsubstituted thienyl;

more preferably, D₁～D₄Independently selected from one of the following substituted or unsubstituted groups: deuterium, furyl, benzofuryl, isobenzofuryl, dibenzofuryl, thienyl, benzothienyl, isobenzothienyl, dibenzothienyl, pyrrolyl, isoindolyl, carbazolyl, indenocarbazolyl, pyridyl, quinolyl, isoquinolyl, acridinyl, phenanthridinyl, benzo-5, 6-quinolyl, benzo-6, 7-quinolyl, benzo-7, 8-quinolyl, pyrazolyl, indazolyl, imidazolyl, benzimidazolyl, naphthoimidazolyl, phenanthroimidazolyl, pyridoimidazolyl, pyrazinoimidazolyl, quinoxalinyl, oxazolyl, benzoxazolyl, naphthooxazolyl, anthraoxazolyl, phenanthroizolyl, 1, 2-thiazolyl, 1, 3-thiazolyl, benzothiazolyl, pyridazinyl, pyrimidyl, benzopyrimidinyl, Quinoxalinyl, 1, 5-diazahthranyl, 2, 7-diazpyrenyl, 2, 3-diazpyrenyl, 1, 6-diazpyrenyl, 1, 8-diazpyrenyl, 4,5,9, 10-tetraazaperylenyl, pyrazinyl, phenazinyl, phenothiazinyl, naphthyridinyl, azacarbazolyl, benzocarbazinyl, phenanthrolinyl, 1,2, 3-triazolyl, 1,2, 4-triazolyl, benzotriazolyl, 1,2, 3-oxadiazolyl, 1,2, 4-oxadiazolyl, 1,2, 5-oxadiazolyl, 1,2, 3-thiadiazolyl, 1,2, 4-thiadiazolyl, 1,2, 5-thiadiazolyl, 1,3, 4-thiadiazolyl, 1,3, 5-triazinyl, 1,2, 4-triazinyl, 1,2, 3-triazinyl, tetrazolyl, 1,2,4, 5-tetrazinyl, 1,2,3, 4-tetrazinyl, 1,2,3, 5-tetrazinyl, purinyl, pteridinyl, indolizinylA group, a benzothiadiazolyl group, a 9, 9-dimethylazlidinyl group, or a combination selected from the two above groups.

A is selected from one of substituted or unsubstituted monocyclic heteroaryl containing C3-C60 and at least one nitrogen atom, substituted or unsubstituted fused ring heteroaryl containing C3-C60 and at least one nitrogen atom, or a substituent selected from the following structures, wherein Ar is Ar₁、Ar₂、Ar₃、Ar₄And Ar₅Each independently selected from one of a substituted or unsubstituted monocyclic aryl group of C6-C60 and a substituted or unsubstituted fused ring aryl group of C6-C60;

NC-＊NC-Ar₁-＊

r is selected from one of substituted or unsubstituted C6-C30 aryl, substituted or unsubstituted C3-C30 monocyclic heteroaryl, substituted or unsubstituted C3-C30 fused ring heteroaryl, or a substituent group with the following structure, wherein Ar is Ar₁、Ar₂、Ar₃、Ar₄And Ar₅Each independently selected from one of substituted or unsubstituted C6-C60 monocyclic aryl and substituted or unsubstituted C6-C60 condensed ring aryl, R₁、R₂、R₃And R₄Each independently selected from the group consisting of C1-C30 alkyl, C6-C60 aryl, and when R is selected from the group consisting of substituted or unsubstituted C3-C30 monocyclic heteroaryl, substituted or unsubstituted C3-C30 fused ring heteroaryl, the heteroatoms in the monocyclic heteroaryl and fused ring heteroaryl may further include an oxygen atom, a sulfur atom, or a selenium atom:

NC-＊NC-Ar₁-＊

when the substituent exists on the substituent group, the substituent group is selected from one or more of C1-C30 chain alkyl, C3-C30 naphthenic base, C1-C6 alkoxy, C6-C30 aryl and C3-C60 heteroaryl.

Further, in formula (1), a is preferably a group represented by the following structure:

further, R is preferably a group represented by the following structure:

still further, in the above formula (1), D₁～D₄Each independently selected from deuterium or from a group represented by the structure:

and represents the position of the bond of the substituent group.

The structural characteristics of the compounds are that A, R is positioned at the para position of a central benzene ring to form an A-pi-A structure, and D₁、D₃And D₂、D₄The structure is in para position of benzene ring to form D-pi-D structure, and the design idea can effectively regulate and control the front line orbit distribution of molecules, regulate the charge transfer excited state property of the molecules, improve the oscillator strength of the molecules and improve the luminous efficiency. R group and D₂、D₃The groups form molecular orbitals overlapping on the space, enhance the charge transfer excited state (TSCT) passing through the space, and promote the transition rate between reverse systems of molecules, thereby realizing an OLED device with high efficiency and long service life.

Further, the compounds represented by the general formula (1) of the present invention may preferably be compounds C1 to C219 of the following specific structures: these compounds are representative only:

further, the compounds represented by the general formula (1) of the present invention may be preferably selected from the specific table compounds C220 to C3969 shown in table 1 below. In Table 1, the column "C" represents the compound number, the column "A" represents the specific structural formula number selected from the substituent group A in the general formula (1), "R" represents the specific structural formula number selected from the substituent group R in the general formula (1), "D" represents the substituent group D in the general formula (1)₁～D₄Independently and simultaneously selected from specific structural formula numbers. These compounds in table 1 are representative only.

Table 1:

the present invention also provides the use of a compound of formula (1) as a functional material in an organic electronic device comprising: an organic electroluminescent device, an optical sensor, a solar cell, a lighting element, an organic thin film transistor, an organic field effect transistor, an organic thin film solar cell, an information label, an electronic artificial skin sheet, a sheet type scanner, or electronic paper, preferably an organic electroluminescent device.

The present invention also provides an organic electroluminescent device comprising a substrate comprising a first electrode, a second electrode and one or more organic layers interposed between the first electrode and the second electrode, wherein the organic layer comprises the compound represented by any one of the above-described formula (1) of the present invention or comprises any one of the above-described specific compounds of the present invention C1 to C3969.

Specifically, embodiments of the present invention provide an organic electroluminescent device including a substrate, and an anode layer, a plurality of light emitting functional layers, and a cathode layer sequentially formed on the substrate; the light-emitting functional layer comprises a hole injection layer, a hole transport layer, a light-emitting layer and an electron transport layer, wherein the hole injection layer is formed on the anode layer, the hole transport layer is formed on the hole injection layer, the cathode layer is formed on the electron transport layer, and the light-emitting layer is arranged between the hole transport layer and the electron transport layer; among them, it is preferable that the light-emitting layer contains a compound represented by any one of the above formula (1) of the present invention, or includes any one of the above specific compounds C1 to C3969.

The OLED device prepared by the compound has low starting voltage, high luminous efficiency and better service life.

The specific reason why the above-mentioned compound of the present invention is excellent when used in an organic electroluminescent device is not clear, and the following is the presumption of the inventors, but these presumptions do not limit the scope of the present invention.

1. The existence of A-pi-A and D-pi-D structures in the compound increases the delocalization degree of HOMO and LUMO, and improves the luminous efficiency;

2. the compound of the invention has a structural formula in which R is at D₂And D4 group, the charge transfer excitation through space is enhanced, and the reverse intersystem crossing rate is increased.

The general formula compound of the invention adopts benzene as a mother nucleus, has A-pi-A and D-pi-D structures, an acceptor group (A) and a pi group (R) on the mother nucleus are in the para position of a central benzene ring, and a donor group (D)₁～D₄) Also in para position to the central benzene ring, the structure has the advantages of:

1) the LUMO delocalization degree is increased, the property of a charge transfer excited state is enhanced, and the luminous efficiency is improved.

2) The LUMO delocalization degree is increased, the bond energy BDE-of the weakest bond in the molecule is increased after one electron is obtained, and the improvement of the molecular stability is facilitated.

3) The molecule has charge transfer excitation through space, and the reverse system cross rate is improved.

Detailed Description

The specific production method of the above-mentioned novel compound of the present invention will be described in detail below by taking a plurality of synthesis examples as examples, but the production method of the present invention is not limited to these synthesis examples.

The synthesis of the compounds of the present invention is briefly described below.

Synthetic examples

Synthesis example 1: synthesis of Compound C1

Synthesis of intermediate 1:

4-bromo-2, 3,5, 6-tetrafluoronitrile (2.54g, 10mmol), p-cyanoboronic acid (1.47g, 10mmol), palladium tetratriphenylphosphine (0.58g, 0.5mmol) were dissolved in 30mL of toluene and potassium carbonate (2.76g, 20mmol) in 15mL of deionized water in a 100mL three-necked flask under a nitrogen atmosphere, and the two were mixed and reacted at 90 ℃ for 24 hours. Then, extraction with dichloromethane (50 mL. times.3), liquid separation, column chromatography gave 2.1g of a white solid in 76.3% yield.

Synthesis of compound C1:

carbazole (5g, 30mmol) and sodium hydride (1.68g, 42mmol) were dissolved in 20mL of DMF under nitrogen in a 100mL three-necked flask and stirred for 1 hour, then the DMF solution containing intermediate 1(1.93g, 7mmol) was added dropwise, after all additions heated to 80 ℃ and stirred overnight. The reaction solution was then poured into water, filtered to give a solid, which was purified by column chromatography to give C1 as a yellow solid in 90% yield.

Product mass spectrum (m/e): 865.01, elemental analysis: theoretical value C, 86.09; h, 4.20; n,9.72, found C, 86.11; h, 4.22; and N, 9.70.

Synthesis of compound C2:

synthesis of intermediate 2:

4-bromo-2, 3,5, 6-tetrafluorobenzonitrile (2.54g, 10mmol), (4, 6-diphenyl-1, 3, 5-triazin-2-yl) boronic acid (2.77g, 10mmol), and palladium tetrakistriphenylphosphine (0.58g, 0.5mmol) were dissolved in 30mL of toluene and potassium carbonate (2.76g, 20mmol) was dissolved in 15mL of deionized water in a 100mL three-necked flask under a nitrogen atmosphere, and the two were mixed and reacted at 90 ℃ for 24 hours. Followed by extraction with dichloromethane (50 mL. times.3), liquid separation, and column chromatography to give 3.5g of a white solid, 86.1% yield.

Synthesis of compound C2:

carbazole (5g, 30mmol) and sodium hydride (1.68g, 42mmol) were dissolved in 20mL of DMF under nitrogen in a 100mL three-necked flask and stirred for 1 hour, then the DMF solution containing intermediate 2(2.84g, 7mmol) was added dropwise, after all additions heated to 80 ℃ and stirred overnight. The reaction solution was then poured into water, filtered to give a solid, and purified by column chromatography to give C2 as a yellow solid in 84% yield.

Product mass spectrum (m/e): 995.16, elemental analysis: theoretical value C, 84.49; h, 4.25; n,11.26, found C, 84.53; h, 4.27; n, 11.22.

Synthesis of compound C3:

synthesis of intermediate 3:

4-bromo-2, 3,5, 6-tetrafluoronitrile (2.54g, 10mmol) was dissolved in 30mL of THF in a 100mL three-necked flask under nitrogen atmosphere, cooled to 0 deg.C, and n-butyllithium (8mL, 2.5mol/L) was added dropwise to the three-necked flask and stirred for 30 min. Bis (tritolyl) boron fluoride (4.02g, 15mmol) was dissolved in 10mL THF, cooled to 0 deg.C, added dropwise to a three-necked flask, and allowed to warm to room temperature for 24 h. The reaction solution was then poured into a saturated ammonium chloride solution and extracted with dichloromethane. The extract was washed with saturated brine, dried over anhydrous sodium sulfate, and recrystallized from ethanol to give 3.0g of a white solid with a yield of 70.88%.

Synthesis of compound C3:

carbazole (5g, 30mmol) and sodium hydride (1.68g, 42mmol) were dissolved in 20mL of DMF under nitrogen in a 100mL three-necked flask and stirred for 1 hour, then the DMF solution containing intermediate 3(2.96g, 7mmol) was added dropwise, after all additions heated to 80 ℃ and stirred overnight. The reaction solution was then poured into water, filtered to give a solid, which was purified by column chromatography to give C3 as a yellow solid in 82% yield.

Product mass spectrum (m/e): 1012.08, elemental analysis: theoretical value C, 86.63; h, 5.38; b, 1.07; n,6.92, found C, 86.67; h, 5.36; b, 1.11; and N, 6.90.

Synthesis of compound C4:

synthesis of intermediate 4:

4-bromo-2, 3,5, 6-tetrafluoronitrile (2.54g, 10mmol) was dissolved in 30mL of THF in a 100mL three-necked flask under nitrogen atmosphere, cooled to 0 deg.C, and n-butyllithium (8mL, 2.5mol/L) was added dropwise to the three-necked flask and stirred for 30 min. Diphenyl phosphine (4.02g, 15mmol) is dissolved in 10mL THF, cooled to 0 ℃, added dropwise into a three-necked flask, heated to room temperature for reaction for 24h, added with hydrogen peroxide and stirred for 3 h. The reaction solution was then poured into a saturated ammonium chloride solution and extracted with dichloromethane. The extract was washed with saturated brine, dried over anhydrous sodium sulfate, and recrystallized from ethanol to give 3.0g of a white solid with a yield of 70.88%.

Synthesis of compound C4:

carbazole (5g, 30mmol) and sodium hydride (1.68g, 42mmol) were dissolved in 20mL of DMF under nitrogen in a 100mL three-necked flask and stirred for 1 hour, then a solution of intermediate 4(2.63g, 7mmol) in DMF was added dropwise, and after all additions, the mixture was heated to 80 ℃ and stirred overnight. The reaction solution was then poured into water, filtered to give a solid, which was purified by column chromatography to give C4 as a yellow solid in 72.6% yield.

Product mass spectrum (m/e): 964.08, elemental analysis: theoretical value C, 83.47; h, 4.39; n, 7.26; o, 1.66; p,3.21, found C, 83.50; h, 4.37; n, 7.28; o, 1.67; p, 3.23.

Synthesis of compound C5:

synthesis of intermediate 5:

4-cyano-2, 3,5, 6-tetrafluorophenylboronic acid (2.19g, 10mmol), 2-bromo-5, 7-diphenyltriazolotriazine (3.52g, 10mmol), and tetrakistriphenylphosphine palladium (0.58g, 0.5mmol) were dissolved in 30mL of toluene and potassium carbonate (2.76g, 20mmol) in 15mL of deionized water in a 100mL three-necked flask under a nitrogen atmosphere, and the two were mixed and reacted at 90 ℃ for 24 hours. Followed by extraction with dichloromethane (50 mL. times.3), liquid separation, and column chromatography to give 3.5g of a white solid in 78.4% yield.

Synthesis of compound C5:

carbazole (5g, 30mmol) and sodium hydride (1.68g, 42mmol) were dissolved in 20mL of DMF under nitrogen in a 100mL three-necked flask and stirred for 1 hour, then a solution of intermediate 5(3.12g, 7mmol) in DMF was added dropwise, and after all additions, the mixture was heated to 80 ℃ and stirred overnight. The reaction solution was then poured into water, filtered to give a solid, which was purified by column chromatography to give C5 as a yellow solid in 79% yield.

Product mass spectrum (m/e): 1035.19, elemental analysis: theoretical value C, 82.38; h, 4.09; n,13.53, found C, 82.40; h, 4.11; n, 13.58.

Synthetic example 6: synthesis of Compound C6

Synthesis of intermediate 6:

4-bromo-2, 3,5, 6-tetrafluoronitrile (2.54g, 10mmol), 4-pyridineboronic acid (1.23g, 10mmol), and palladium tetratriphenylphosphine (0.58g, 0.5mmol) were dissolved in 30mL of toluene and potassium carbonate (2.76g, 20mmol) was dissolved in 15mL of deionized water in a 100mL three-necked flask under a nitrogen atmosphere, and the two were mixed and reacted at 90 ℃ for 24 hours. Followed by extraction with dichloromethane (50 mL. times.3), liquid separation, and column chromatography to give 2.0g of a white solid in 79.3% yield.

Synthesis of compound C6:

carbazole (5g, 30mmol) and sodium hydride (1.68g, 42mmol) were dissolved in 20mL of DMF under nitrogen in a 100mL three-necked flask and stirred for 1 hour, then the DMF solution containing intermediate 6(1.77g, 7mmol) was added dropwise, after all additions heated to 80 ℃ and stirred overnight. The reaction solution was then poured into water, filtered to give a solid, which was purified by column chromatography to give C6 as a yellow solid in 86.1% yield.

Product mass spectrum (m/e): 840.99, elemental analysis: theoretical value C, 85.69; h, 4.31; n,9.99, found C, 85.67; h, 4.30; n, 10.00.

Synthetic example 7: synthesis of Compound C7

Synthesis of intermediate 7:

the 4-pyridineboronic acid in synthetic example 6 was replaced with 3-pyridineboronic acid, yielding 2.1g of a white solid in 83.3% yield.

Synthesis of compound C7:

carbazole (5g, 30mmol) and sodium hydride (1.68g, 42mmol) were dissolved in 20mL of DMF under nitrogen in a 100mL three-necked flask and stirred for 1 hour, then the DMF solution containing intermediate 7(1.77g, 7mmol) was added dropwise, after all additions heated to 80 ℃ and stirred overnight. The reaction solution was then poured into water, filtered to give a solid, which was purified by column chromatography to give C7 as a yellow solid in 88.2% yield.

Product mass spectrum (m/e): 840.99, elemental analysis: theoretical value C, 85.69; h, 4.31; n,9.99, found C, 85.69; h, 4.33; and N, 10.02.

Synthesis example 8: synthesis of Compound C8

Synthesis of intermediate 8:

the 4-pyridineboronic acid in synthetic example 6 was replaced with 2-pyridineboronic acid, yielding 2.0g of a white solid in 79.3% yield.

Synthesis of compound C8:

carbazole (5g, 30mmol) and sodium hydride (1.68g, 42mmol) were dissolved in 20mL of DMF under nitrogen in a 100mL three-necked flask and stirred for 1 hour, then the DMF solution containing intermediate 8(1.77g, 7mmol) was added dropwise, after all additions heated to 80 ℃ and stirred overnight. The reaction solution was then poured into water, filtered to give a solid, which was purified by column chromatography to give C8 as a yellow solid in 84.9% yield.

Product mass spectrum (m/e): 840.99, elemental analysis: theoretical value C, 85.69; h, 4.31; n,9.99, found C, 85.65; h, 4.29; and N, 10.01.

Synthetic example 9: synthesis of Compound C9

Synthesis of intermediate 9:

the 4-pyridineboronic acid in synthetic example 6 was replaced with 5-pyrimidineboronic acid, yielding 2.1g of a white solid with a yield of 82.9%.

Synthesis of compound C9:

carbazole (5g, 30mmol) and sodium hydride (1.68g, 42mmol) were dissolved in 20mL of DMF under nitrogen in a 100mL three-necked flask and stirred for 1 hour, then the DMF solution containing intermediate 9(1.77g, 7mmol) was added dropwise, after all additions heated to 80 ℃ and stirred overnight. The reaction solution was then poured into water, filtered to give a solid, which was purified by column chromatography to give C9 as a yellow solid in 89.6% yield.

Product mass spectrum (m/e): 840.99, elemental analysis: theoretical value C, 84.16; h, 4.19; n,11.65, found C, 84.13; h, 4.21; n, 11.66.

Synthetic example 10: synthesis of Compound C10

Synthesis of intermediate 10:

1, 4-bromo-2, 3,5, 6-tetrafluorobenzene (3.08g, 10mmol), p-cyanobenzenesulfonic acid (3.23g, 22mmol), and palladium tetratriphenylphosphine (0.58g, 0.5mmol) were dissolved in 30mL of toluene and potassium carbonate (2.76g, 20mmol) in 15mL of deionized water in a 100mL three-necked flask under a nitrogen atmosphere, and the two were mixed and reacted at 90 ℃ for 24 hours. Followed by extraction with dichloromethane (50 mL. times.3), liquid separation, and column chromatography to give 3.1g of a white solid in 88.0% yield.

Synthesis of compound C10:

carbazole (5g, 30mmol) and sodium hydride (1.68g, 42mmol) were dissolved in 20mL of DMF under nitrogen in a 100mL three-necked flask and stirred for 1 hour, then a solution of intermediate 10(2.47g, 7mmol) in DMF was added dropwise, and after all additions, the mixture was heated to 80 ℃ and stirred overnight. The reaction solution was then poured into water, filtered to give a solid, which was purified by column chromatography to give C10 as a yellow solid in 83.5% yield.

Product mass spectrum (m/e): 941.11, elemental analysis: theoretical value C, 86.79; h, 4.28; n,8.93, found C, 86.81; h, 4.30; and N, 8.90.

Synthetic example 11: synthesis of Compound C11

Synthesis of intermediate 11:

1, 4-bromo-2, 3,5, 6-tetrafluorobenzene (3.08g, 10mmol), p-cyanobenzenesulfonic acid (1.47g, 10mmol), and palladium tetratriphenylphosphine (0.58g, 0.5mmol) were dissolved in 30mL of toluene and potassium carbonate (2.76g, 20mmol) in 15mL of deionized water in a 100mL three-necked flask under a nitrogen atmosphere, and the two were mixed and reacted at 90 ℃ for 24 hours. Followed by extraction with dichloromethane (50 mL. times.3), liquid separation, and column chromatography to give 2.5g of a white solid in 75.7% yield.

Synthesis of intermediate 11-2:

consistent with the synthesis of intermediate 2, the 4-bromo-2, 3,5, 6-tetrafluorobenzonitrile used in the synthesis of intermediate 2 was replaced with intermediate 11(3.3g, 10 mmol).

Synthesis of compound C11:

carbazole (5g, 30mmol) and sodium hydride (1.68g, 42mmol) were dissolved in 20mL of DMF under nitrogen in a 100mL three-necked flask and stirred for 1 hour, then the DMF solution containing intermediate 11-2(3.38g, 7mmol) was added dropwise, and after all addition was heated to 80 ℃ and stirred overnight. The reaction solution was then poured into water, filtered to give a solid, which was purified by column chromatography to give C11 as a yellow solid in 79.6% yield.

Product mass spectrum (m/e): 941.11, elemental analysis: theoretical value C, 86.79; h, 4.28; n,8.93, found C, 86.81; h, 4.30; and N, 8.90.

Synthetic example 12: synthesis of Compound C12

Synthesis of intermediate 12:

consistent with the synthesis of intermediate 3, the 4-bromo-2, 3,5, 6-tetrafluorobenzonitrile used in the synthesis of intermediate 3 was replaced with intermediate 11(3.3g, 10 mmol).

Synthesis of compound C12:

carbazole (5g, 30mmol) and sodium hydride (1.68g, 42mmol) were dissolved in 20mL of DMF under nitrogen in a 100mL three-necked flask and stirred for 1 hour, then a solution of intermediate 12(3.38g, 7mmol) in DMF was added dropwise, and after all additions, the mixture was heated to 80 ℃ and stirred overnight. The reaction solution was then poured into water, filtered to give a solid, which was purified by column chromatography to give C12 as a yellow solid in 69.5% yield.

Product mass spectrum (m/e): 1088.18, elemental analysis: theoretical value C, 87.20; h, 5.37; b, 0.99; n,6.44, found C, 87.21; h, 5.37; b, 0.87; and N, 6.42.

Synthetic example 13: synthesis of Compound C13

Synthesis of intermediate 13:

in keeping with the synthesis of intermediate 4, the 4-bromo-2, 3,5, 6-tetrafluorobenzonitrile used in the synthesis of intermediate 3 was replaced with intermediate 11(3.3g, 10 mmol).

Synthesis of compound C13:

carbazole (5g, 30mmol) and sodium hydride (1.68g, 42mmol) were dissolved in 20mL of DMF under nitrogen in a 100mL three-necked flask and stirred for 1 hour, then a solution of intermediate 12(3.38g, 7mmol) in DMF was added dropwise, and after all additions, the mixture was heated to 80 ℃ and stirred overnight. The reaction solution was then poured into water, filtered to give a solid, which was purified by column chromatography to give C13 as a yellow solid in 77.5% yield.

Product mass spectrum (m/e): 1088.18, elemental analysis: theoretical value C, 87.20; h, 5.37; b, 0.99; n,6.44, found C, 87.21; h, 5.37; b, 0.87; and N, 6.42.

Synthesis example 14: synthesis of Compound C15

Synthesis of intermediate 14:

consistent with the synthesis of intermediate 6, the 4-bromo-2, 3,5, 6-tetrafluorobenzonitrile used in the synthesis of intermediate 6 was replaced with intermediate 11(3.3g, 10 mmol).

Synthesis of compound C15:

carbazole (5g, 30mmol) and sodium hydride (1.68g, 42mmol) were dissolved in 20mL of DMF under nitrogen in a 100mL three-necked flask and stirred for 1 hour, then the DMF solution containing intermediate 14(2.3g, 7mmol) was added dropwise, after all additions heated to 80 ℃ and stirred overnight. The reaction solution was then poured into water, filtered to give a solid, which was purified by column chromatography to give C15 as a yellow solid in 86.4% yield.

Product mass spectrum (m/e): 917.09, elemental analysis: theoretical value C, 86.44; h, 4.40; n,9.16, found C, 86.46; h, 4.40; and N, 9.17.

Synthetic example 15: synthesis of Compound C16

Synthesis of intermediate 15:

consistent with the synthesis of intermediate 14, the 4-pyridineboronic acid used in the synthesis of intermediate 14 was replaced with 3-pyridineboronic acid ((1.23g, 10 mmol).

Synthesis of compound C16:

carbazole (5g, 30mmol) and sodium hydride (1.68g, 42mmol) were dissolved in 20mL of DMF under nitrogen in a 100mL three-necked flask and stirred for 1 hour, then the DMF solution containing intermediate 16(2.3g, 7mmol) was added dropwise, after all additions heated to 80 ℃ and stirred overnight. The reaction solution was then poured into water, filtered to give a solid, which was purified by column chromatography to give C16 as a yellow solid in 90.1% yield.

Product mass spectrum (m/e): 917.09, elemental analysis: theoretical value C, 86.44; h, 4.40; n,9.16, found C, 86.46; h, 4.38; and N, 9.14.

Synthetic example 16: synthesis of Compound C17

Synthesis of intermediate 16:

consistent with the synthesis of intermediate 14, the 4-pyridineboronic acid used in the synthesis of intermediate 14 was replaced with 2-pyridineboronic acid ((1.23g, 10 mmol).

Synthesis of compound C17:

carbazole (5g, 30mmol) and sodium hydride (1.68g, 42mmol) were dissolved in 20mL of DMF under nitrogen in a 100mL three-necked flask and stirred for 1 hour, then a solution of intermediate 17(2.3g, 7mmol) in DMF was added dropwise, and after all additions, the mixture was heated to 80 ℃ and stirred overnight. The reaction solution was then poured into water, filtered to give a solid, which was purified by column chromatography to give C17 as a yellow solid in 79.5% yield.

Product mass spectrum (m/e): 917.09, elemental analysis: theoretical value C, 86.44; h, 4.40; n,9.16, found C, 86.44; h, 4.40; and N, 9.15.

Synthetic example 17: synthesis of Compound C18

Synthesis of intermediate 17:

consistent with the synthesis of intermediate 14, the 4-pyridineboronic acid used in the synthesis of intermediate 14 was replaced with 5-pyrimidineboronic acid ((1.23g, 10 mmol).

Synthesis of compound C18:

carbazole (5g, 30mmol) and sodium hydride (1.68g, 42mmol) were dissolved in 20mL of DMF under nitrogen in a 100mL three-necked flask and stirred for 1 hour, then the DMF solution containing intermediate 18(2.3g, 7mmol) was added dropwise, after all additions heated to 80 ℃ and stirred overnight. The reaction solution was then poured into water, filtered to give a solid, which was purified by column chromatography to give C18 as a yellow solid in 86.4% yield.

Product mass spectrum (m/e): 917.09, elemental analysis: theoretical value C, 86.44; h, 4.40; n,9.16, found C, 86.45; h, 4.43; and N, 9.19.

Synthetic example 18: synthesis of Compound C55

Synthesis of intermediate 18:

4-bromo-2, 3,5, 6-tetrafluoronitrile (2.54g, 10mmol), phenylboronic acid (1.22g, 10mmol), and palladium tetratriphenylphosphine (0.58g, 0.5mmol) were dissolved in 30mL of toluene and potassium carbonate (2.76g, 20mmol) was dissolved in 15mL of deionized water in a 100mL three-necked flask under a nitrogen atmosphere, and the two were mixed and reacted at 90 ℃ for 24 hours. Then, extraction with dichloromethane (50 mL. times.3), liquid separation, column chromatography gave 2.1g of a white solid in 83.6% yield.

Synthesis of compound C55:

carbazole (5g, 30mmol) and sodium hydride (1.68g, 42mmol) were dissolved in 20mL of DMF under nitrogen in a 100mL three-necked flask and stirred for 1 hour, then the DMF solution containing intermediate 18(1.76g, 7mmol) was added dropwise, after all additions heated to 80 ℃ and stirred overnight. The reaction solution was then poured into water, filtered to give a solid, which was purified by column chromatography to give C55 as a yellow solid in 90.6% yield.

Product mass spectrum (m/e): 840.0, elemental analysis: theoretical value C, 87.22; h, 4.44; n,8.34, found C, 87.20; h, 4.46; n, 8.34.

Synthetic example 19: synthesis of Compound C56

Synthesis of intermediate 19:

4-bromo-2, 3,5, 6-tetrafluorobenzonitrile (2.54g, 10mmol), dibenzofuran-2-boronic acid (2.12g, 10mmol), palladium tetratriphenylphosphine (0.58g, 0.5mmol) were dissolved in 30mL of toluene and potassium carbonate (2.76g, 20mmol) in 15mL of deionized water in a 100mL three-necked flask under a nitrogen atmosphere, and the two were mixed and reacted at 90 ℃ for 24 hours. Followed by extraction with dichloromethane (50 mL. times.3), liquid separation, and column chromatography to give 3g of a white solid with a yield of 87.9%.

Synthesis of compound C56:

carbazole (5g, 30mmol) and sodium hydride (1.68g, 42mmol) were dissolved in 20mL of DMF under nitrogen in a 100mL three-necked flask and stirred for 1 hour, then the DMF solution containing intermediate 19(2.39g, 7mmol) was added dropwise, after all additions heated to 80 ℃ and stirred overnight. The reaction solution was then poured into water, filtered to give a solid, which was purified by column chromatography to give C56 as a yellow solid in 86.6% yield.

Product mass spectrum (m/e): 930.8, elemental analysis: theoretical value C, 86.52; h, 4.23; n, 7.53; o,1.72, found C, 86.50; h, 4.24; n, 7.54; o, 1.73.

Synthesis example 20: synthesis of Compound C57

Synthesis of intermediate 20:

4-bromo-2, 3,5, 6-tetrafluorobenzonitrile (2.54g, 10mmol), dibenzothiophene-2-boronic acid (2.28g, 10mmol), palladium tetratriphenylphosphine (0.58g, 0.5mmol) were dissolved in 30mL of toluene and potassium carbonate (2.76g, 20mmol) in 15mL of deionized water in a 100mL three-necked flask under a nitrogen atmosphere, and the two were mixed and reacted at 90 ℃ for 24 hours. Followed by extraction with dichloromethane (50 mL. times.3), liquid separation, and column chromatography to give 3g of a white solid in 83.9% yield.

Synthesis of compound C57:

carbazole (5g, 30mmol) and sodium hydride (1.68g, 42mmol) were dissolved in 20mL of DMF under nitrogen in a 100mL three-necked flask and stirred for 1 hour, then the DMF solution containing intermediate 20(2.50g, 7mmol) was added dropwise, after all additions heated to 80 ℃ and stirred overnight. The reaction solution was then poured into water, filtered to give a solid, which was purified by column chromatography to give C57 as a yellow solid in 84.1% yield.

Product mass spectrum (m/e): 946.14, elemental analysis: theoretical value C, 85.05; h, 4.15; n, 7.40; s,3.39, found C, 85.07; h, 4.14; n, 7.41; and S, 3.40.

Synthetic example 21: synthesis of Compound C58

Synthesis of intermediate 21:

4-bromo-2, 3,5, 6-tetrafluorobenzonitrile (2.54g, 10mmol), dibenzothiophene-2-boronic acid (2.75g, 10mmol), palladium tetratriphenylphosphine (0.58g, 0.5mmol) were dissolved in 30mL of toluene and potassium carbonate (2.76g, 20mmol) in 15mL of deionized water in a 100mL three-necked flask under a nitrogen atmosphere, and the two were mixed and reacted at 90 ℃ for 24 hours. Followed by extraction with dichloromethane (50 mL. times.3), liquid separation, and column chromatography to give 2.9g of a white solid in 81.2% yield.

Synthesis of compound C58:

carbazole (5g, 30mmol) and sodium hydride (1.68g, 42mmol) were dissolved in 20mL of DMF under nitrogen in a 100mL three-necked flask and stirred for 1 hour, then the DMF solution containing intermediate 21(2.83g, 7mmol) was added dropwise, after all additions heated to 80 ℃ and stirred overnight. The reaction solution was then poured into water, filtered to give a solid, which was purified by column chromatography to give C58 as a yellow solid in 79.1% yield.

Product mass spectrum (m/e): 946.14, elemental analysis: theoretical value C, 81.04; h, 3.96; n, 7.05; se,7.95, found C, 81.03; h, 3.97; n, 7.06; se, 7.96.

Synthetic example 22: synthesis of Compound C59

Synthesis of intermediate 22:

4-bromo-2, 3,5, 6-tetrafluorobenzonitrile (2.54g, 10mmol), xanthone-3-boronic acid (2.40g, 10mmol), palladium tetratriphenylphosphine (0.58g, 0.5mmol) were dissolved in 30mL of toluene and potassium carbonate (2.76g, 20mmol) in 15mL of deionized water in a 100mL three-necked flask under a nitrogen atmosphere, and the two were mixed and reacted at 90 ℃ for 24 hours. Followed by extraction with dichloromethane (50 mL. times.3), liquid separation, and column chromatography to give 3.1g of a white solid in 83.9% yield.

Synthesis of compound C59:

carbazole (5g, 30mmol) and sodium hydride (1.68g, 42mmol) were dissolved in 20mL of DMF under nitrogen in a 100mL three-necked flask and stirred for 1 hour, then the DMF solution containing intermediate 21(2.58g, 7mmol) was added dropwise, after all additions heated to 80 ℃ and stirred overnight. The reaction solution was then poured into water, filtered to give a solid, which was purified by column chromatography to give C59 as a yellow solid in 81.2% yield.

Product mass spectrum (m/e): 958.09, elemental analysis: theoretical value C, 85.25; h, 4.10; n, 7.31; o,3.34, found C, 85.24; h, 4.08; n, 7.33; and O, 3.36.

Synthetic example 23: synthesis of Compound C60

Synthesis of intermediate 23:

the synthesis method is the same as intermediate 21, and xanthone-3-boronic acid is replaced with 9-thia-xanthone-3-boronic acid (2.60g,10mmol) to obtain white solid 3.0g, with a yield of 79.6%

Synthesis of compound C60:

the synthesis was identical to compound C59, substituting intermediate 21 for intermediate 23(2.69g, 7mmol) to afford C60 as a yellow solid in 76.9% yield.

Product mass spectrum (m/e): 974.15, elemental analysis: theoretical value C, 83.84; h, 4.04; n, 7.19; o, 1.64; s,3.29, found C, 83.82; h, 4.06; n, 7.21; o, 1.65; and S, 3.30.

Synthetic example 24: synthesis of Compound C61

Synthesis of intermediate 24:

the synthesis method is the same as intermediate 21, and xanthone-3-boronic acid is replaced with 9-selena-xanthone-3-boronic acid (2.80g,10mmol) to obtain white solid 2.9g, yield 82%

Synthesis of compound C61:

the synthesis was identical to compound C59, substituting intermediate 21 for intermediate 24(2.6g, 7mmol) to afford C61 as a yellow solid in 70.9% yield.

Product mass spectrum (m/e): 1021.07, elemental analysis: theoretical value C, 79.99; h, 3.85; n, 6.86; o, 1.57; se,7.73, found C, 79.97; h, 3.84; n, 6.88; o, 1.55; se, 7.75.

Synthetic example 25: synthesis of Compound C62

Synthesis of intermediate 25:

the synthesis method is the same as intermediate 21, substituting xanthone-3-boronic acid with triphenylene-1-boronic acid (2.6g,10mmol) to obtain white solid 3.1g, yield 88.6%

Synthesis of compound C62:

the synthesis was identical to compound C59, substituting intermediate 21 for intermediate 25(3.0g, 7mmol) to afford C62 as a yellow solid in 81.3% yield.

Product mass spectrum (m/e): 990.18, elemental analysis: theoretical value C, 88.55; h, 4.38; n,7.07, found C, 88.54; h, 4.39; and N, 7.06.

Synthetic example 26: synthesis of Compound C63

Synthesis of intermediate 26:

the synthesis method is the same as intermediate 21, substituting xanthone-3-boronic acid with triphenylene-2-boronic acid (2.6g,10mmol) to obtain white solid 3.0g, yield 86.6%

Synthesis of compound C63:

the synthesis was identical to compound C59, substituting intermediate 21 for intermediate 26(3.0g, 7mmol) to afford C63 as a yellow solid in 84.3% yield.

Product mass spectrum (m/e): 990.18, elemental analysis: theoretical value C, 88.55; h, 4.38; n,7.07, found C, 88.54; h, 4.39; and N, 7.06.

Synthetic example 27: synthesis of Compound C66

Synthesis of intermediate 27:

the synthesis method is the same as intermediate 21, except that xanthone-3-boronic acid is replaced with 2-naphthalene boronic acid (2.1g,10mmol) to obtain white solid 2.8g, yield 89.6%

Synthesis of compound C66:

the synthesis was identical to compound C59, substituting intermediate 21 for intermediate 27(2.7g, 7mmol) to afford C66 as a yellow solid in 85.8% yield.

Product mass spectrum (m/e): 890.06, elemental analysis: theoretical value C, 87.71; h, 4.42; n,7.87, found C, 87.73; h, 4.41; and N, 7.88.

Synthetic example 30: synthesis of Compound C67

Synthesis of intermediate 30:

the synthesis method is the same as intermediate 21, and xanthone-3-boronic acid is replaced by 1-naphthalene boronic acid (2.1g,10mmol) to obtain white solid 2.9g, with yield 92.6%

Synthesis of compound C67:

the synthesis was identical to compound C59, substituting intermediate 21 for intermediate 30(2.7g, 7mmol) to afford C67 as a yellow solid in 86.6% yield.

Product mass spectrum (m/e): 890.06, elemental analysis: theoretical value C, 87.71; h, 4.42; n,7.87, found C, 87.70; h, 4.43; n,7.87

Synthetic example 31: synthesis of Compound C68

Synthesis of intermediate 31:

intermediate 11(3.3g, 10mmol), phenylboronic acid (1.22g, 10mmol), and palladium tetratriphenylphosphine (0.58g, 0.5mmol) were dissolved in 30mL of toluene and potassium carbonate (2.76g, 20mmol) was dissolved in 15mL of deionized water in a 100mL three-necked flask under a nitrogen atmosphere, and the two were mixed and reacted at 90 ℃ for 24 hours. Followed by extraction with dichloromethane (50 mL. times.3), liquid separation, and column chromatography to give 3.2g of a white solid, 84.6% yield.

Synthesis of compound C68:

carbazole (5g, 30mmol) and sodium hydride (1.68g, 42mmol) were dissolved in 20mL of DMF under nitrogen in a 100mL three-necked flask and stirred for 1 hour, then the DMF solution containing intermediate 31(2.3g, 7mmol) was added dropwise, after all additions heated to 80 ℃ and stirred overnight. The reaction solution was then poured into water, filtered to give a solid, which was purified by column chromatography to give C68 as a yellow solid in 85.9% yield.

Product mass spectrum (m/e): 916.1, elemental analysis: theoretical value C, 87.84; h, 4.51; n,7.64, found C, 87.82; h, 4.51; and N, 7.65.

Synthetic example 32: synthesis of Compound C69

Synthesis of intermediate 32:

intermediate 11(3.3g, 10mmol), dibenzofuran-2-boronic acid (2.12g, 10mmol), palladium tetrakistriphenylphosphine (0.58g, 0.5mmol) were dissolved in 30mL of toluene and potassium carbonate (2.76g, 20mmol) in 15mL of deionized water in a 100mL three-necked flask under nitrogen atmosphere, and the two were mixed and reacted at 90 ℃ for 24 h. Followed by extraction with dichloromethane (50 mL. times.3), liquid separation, and column chromatography to give 3g of a white solid with a yield of 87.9%.

Synthesis of compound C69:

carbazole (5g, 30mmol) and sodium hydride (1.68g, 42mmol) were dissolved in 20mL of DMF under nitrogen in a 100mL three-necked flask and stirred for 1 hour, then a solution of intermediate 32(2.39g, 7mmol) in DMF was added dropwise, and after all additions, the mixture was heated to 80 ℃ and stirred overnight. The reaction solution was then poured into water, filtered to give a solid, which was purified by column chromatography to give C69 as a yellow solid in 86.6% yield.

Product mass spectrum (m/e): 1005.35, elemental analysis: theoretical value C, 87.14; h, 4.31; n, 6.96; o,1.59, found C, 87.16; h, 4.30; n, 6.95; o, 1.60.

Synthetic example 33: synthesis of Compound C70

Synthesis of intermediate 33:

intermediate 11(3.3g, 10mmol), dibenzothiophene-2-boronic acid (2.28g, 10mmol), palladium tetrakistriphenylphosphine (0.58g, 0.5mmol) were dissolved in 30mL of toluene and potassium carbonate (2.76g, 20mmol) in 15mL of deionized water in a 100mL three-necked flask under a nitrogen atmosphere, and the two were mixed and reacted at 90 ℃ for 24 h. Followed by extraction with dichloromethane (50 mL. times.3), liquid separation, and column chromatography to give 3.3g of a white solid with a yield of 85.8%.

Synthesis of compound C70:

carbazole (5g, 30mmol) and sodium hydride (1.68g, 42mmol) were dissolved in 20mL of DMF under nitrogen in a 100mL three-necked flask and stirred for 1 hour, then the DMF solution containing intermediate 33(2.5g, 7mmol) was added dropwise, after all additions heated to 80 ℃ and stirred overnight. The reaction solution was then poured into water, filtered to give a solid, which was purified by column chromatography to give C70 as a yellow solid in 90.5% yield.

Product mass spectrum (m/e): 1021.32, elemental analysis: theoretical value C, 85.77; h, 4.24; n, 6.85; s,3.14, found C, 85.75; h, 4.25; n, 6.86; and S, 3.14.

Synthesis example 34: synthesis of Compound C71

Synthesis of intermediate 34:

intermediate 11(3.3g, 10mmol), dibenzoselenophene-2-boronic acid (2.75g, 10mmol), palladium tetrakistriphenylphosphine (0.58g, 0.5mmol) were dissolved in 30mL of toluene and potassium carbonate (2.76g, 20mmol) in 15mL of deionized water in a 100mL three-necked flask under nitrogen atmosphere, and the two were mixed and reacted at 90 ℃ for 24 h. Then, extraction with dichloromethane (50 mL. times.3), liquid separation, column chromatography gave 2.9g of a white solid in 85.6% yield.

Synthesis of compound C71:

carbazole (5g, 30mmol) and sodium hydride (1.68g, 42mmol) were dissolved in 20mL of DMF under nitrogen in a 100mL three-necked flask and stirred for 1 hour, then a solution of intermediate 34(2.9g, 7mmol) in DMF was added dropwise, and after all additions, the mixture was heated to 80 ℃ and stirred overnight. The reaction solution was then poured into water, filtered to give a solid, which was purified by column chromatography to give C71 as a yellow solid in 79.1% yield.

Product mass spectrum (m/e): 1069.27, elemental analysis: theoretical value C, 82.01; h, 4.05; n, 6.55; se,7.39, found C, 82.02; h, 4.06; n, 6.54; se, 7.40.

Synthesis example 34: synthesis of Compound C72

Synthesis of intermediate 34:

intermediate 11(3.3g, 10mmol), xanthone-3-boronic acid (2.40g, 10mmol), palladium tetrakistriphenylphosphine (0.58g, 0.5mmol) were dissolved in 30mL toluene and potassium carbonate (2.76g, 20mmol) in 15mL deionized water in a 100mL three-necked flask under nitrogen atmosphere, and the two were mixed and reacted at 90 ℃ for 24 h. Followed by extraction with dichloromethane (50 mL. times.3), liquid separation, and column chromatography to give 3.1g of a white solid, 86.9% yield.

Synthesis of compound C72:

carbazole (5g, 30mmol) and sodium hydride (1.68g, 42mmol) were dissolved in 20mL of DMF under nitrogen in a 100mL three-necked flask and stirred for 1 hour, then a solution of intermediate 34(2.9g, 7mmol) in DMF was added dropwise, and after all additions, the mixture was heated to 80 ℃ and stirred overnight. The reaction solution was then poured into water, filtered to give a solid, which was purified by column chromatography to give C72 as a yellow solid in 80.2% yield.

Product mass spectrum (m/e): 1033.34, elemental analysis: theoretical value C, 85.94; h, 4.19; n, 6.77; o,3.09, found C, 85.96; h, 4.18; n, 6.78; and O, 3.08.

Synthetic example 35: synthesis of Compound C73

Synthesis of intermediate 35:

the synthesis method is the same as intermediate 34, and xanthone-3-boronic acid is replaced with 9-thia-xanthone-3-boronic acid (2.60g,10mmol) to obtain a white solid 3.3g, with a yield of 82.6%

Synthesis of compound C73:

the synthesis was identical to compound C72, substituting intermediate 34 for intermediate 35(2.93g, 7mmol) to afford C73 as a yellow solid in 81.5% yield.

Product mass spectrum (m/e): 1049.32, elemental analysis: theoretical value C, 84.63; h, 4.13; n, 6.67; o, 1.52; s,3.05, found C,84.65H, 4.12; n, 6.66; o, 1.53; and S, 3.06.

Synthetic example 36: synthesis of Compound C74

Synthesis of intermediate 36:

the synthesis method is the same as intermediate 34, and xanthone-3-boronic acid is replaced with 9-selena-xanthone-3-boronic acid (2.80g,10mmol) to obtain white solid 3.0g, yield 85%

Synthesis of compound C74:

the synthesis was identical to compound C72, substituting intermediate 34 for intermediate 36(2.8g, 7mmol) to afford C83 as a yellow solid in 75.9% yield.

Product mass spectrum (m/e): 1097.26, elemental analysis: theoretical value C, 81.01; h, 3.95; n, 6.38; o, 1.46; se,7.20, found C, 81.02; h, 3.96; n, 6.40; o, 1.45; se, 7.21.

Synthetic example 37: synthesis of Compound C75

Synthesis of intermediate 37:

the synthesis method is the same as intermediate 34, substituting xanthone-3-boronic acid with triphenylene-1-boronic acid (2.6g,10mmol) to obtain a white solid 3.1g, with a yield of 88.6%

Synthesis of compound C75:

the synthesis was identical to compound C72, substituting intermediate 34 for intermediate 37(3.0g, 7mmol) to give C86 as a yellow solid in 81.3% yield.

Product mass spectrum (m/e): 1065.38, elemental analysis: theoretical value C, 88.99; h, 4.44; n,6.57, found C, 89.01; h, 4.46; and N, 6.55.

Synthetic example 38: synthesis of Compound C76

Synthesis of intermediate 38:

the synthesis method is the same as intermediate 34, substituting xanthone-3-boronic acid with triphenylene-2-boronic acid (2.6g,10mmol) to obtain a white solid 3.0g, with a yield of 86.6%

Synthesis of compound C76:

the synthesis was identical to compound C72, substituting intermediate 34 for intermediate 38(3.0g, 7mmol) to afford C87 as a yellow solid in 84.3% yield.

Product mass spectrum (m/e): 1065.38, elemental analysis: theoretical value C, 88.99; h, 4.44; n,6.57, found C, 89.01; h, 4.46; and N, 6.55.

Synthetic example 39: synthesis of Compound C78

Synthesis of intermediate 39:

the synthesis method is the same as intermediate 34, and xanthone-3-boronic acid is replaced by 1-naphthalene boronic acid (2.1g,10mmol) to obtain white solid 2.9g, with yield 92.6%

Synthesis of compound C78:

the synthesis was identical to compound C72, substituting intermediate 34 for intermediate 39(2.7g, 7mmol) to afford C89 as a yellow solid in 86.6% yield.

Product mass spectrum (m/e): 965.35, elemental analysis: theoretical value C, 88.26; h, 4.49; n,7.25, found C, 88.26; h, 4.49; n,7.25

Synthetic example 40: synthesis of Compound C196

In a 100mL three-necked flask under nitrogen atmosphere, 3, 6-di-tert-butylcarbazole (8.38g, 30mmol) and sodium hydride (1.68g, 42mmol) were dissolved in 20mL of DMF and stirred for 1 hour, then a solution of DMF in which intermediate 18(1.76g, 7mmol) was dissolved was added dropwise, and after all additions, the mixture was heated to 80 ℃ and stirred overnight. The reaction solution was then poured into water, filtered to give a solid, and purified by column chromatography to give C196 as a yellow solid in 89% yield.

Product mass spectrum (m/e): 1288.81, elemental analysis: theoretical value C, 86.67; h, 7.90; n,5.43, actually measured C, 86.65; h, 7.92; n, 5.41.

Synthesis example 41: synthesis of Compound C197

In a 100mL three-necked flask under nitrogen atmosphere, 3, 6-di-tert-butylcarbazole (8.38g, 30mmol) and sodium hydride (1.68g, 42mmol) were dissolved in 20mL of DMF and stirred for 1 hour, then a solution of DMF in which intermediate 19(2.39g, 7mmol) was dissolved was added dropwise, and after all additions, the mixture was heated to 80 ℃ and stirred overnight. The reaction solution was then poured into water, filtered to give a solid, which was purified by column chromatography to give C197 as a yellow solid in 86.6% yield.

Product mass spectrum (m/e): 1378.82, elemental analysis: theoretical value C, 86.23; h, 7.53; n, 5.08; o,1.16, found C, 86.26; h, 7.54; n, 5.05; o, 1.18.

Synthesis example 42: synthesis of Compound C198

In a 100mL three-necked flask under nitrogen atmosphere, 3, 6-di-tert-butylcarbazole (8.38g, 30mmol) and sodium hydride (1.68g, 42mmol) were dissolved in 20mL of DMF and stirred for 1 hour, and then a DMF solution in which intermediate 20(2.50g, 7mmol) was dissolved was added dropwise, and after all additions, the mixture was heated to 80 ℃ and stirred overnight. The reaction was then poured into water and filtered to give a solid which was purified by column chromatography to give C198 as a yellow solid in 84.1% yield.

Product mass spectrum (m/e): 1394.80, elemental analysis: theoretical value C, 85.24; h, 7.44; n, 5.02; s,2.30, found C, 85.26; h, 7.45; n, 5.00; s, 2.29.

Synthetic example 43: synthesis of Compound C199

In a 100mL three-necked flask under nitrogen atmosphere, 3, 6-di-tert-butylcarbazole (8.38g, 30mmol) and sodium hydride (1.68g, 42mmol) were dissolved in 20mL of DMF and stirred for 1 hour, and then a DMF solution in which intermediate 21(2.83g, 7mmol) was dissolved was added dropwise, and after all additions, the mixture was heated to 80 ℃ and stirred overnight. The reaction solution was then poured into water, filtered to give a solid, which was purified by column chromatography to give C199 as a yellow solid in 79.1% yield.

Product mass spectrum (m/e): 1442.74, elemental analysis: theoretical value C, 82.47; h, 7.20; n, 4.86; se,5.48, found C, 82.46; h, 7.22; n, 4.87; se, 5.46.

Synthetic example 44: synthesis of Compound C200

In a 100mL three-necked flask under nitrogen atmosphere, 3, 6-di-tert-butylcarbazole (8.38g, 30mmol) and sodium hydride (1.68g, 42mmol) were dissolved in 20mL of DMF and stirred for 1 hour, then a solution of intermediate 22(2.58g, 7mmol) in DMF was added dropwise, and after all additions, the mixture was heated to 80 ℃ and stirred overnight. The reaction solution was then poured into water, filtered to give a solid, which was purified by column chromatography to give C200 as a yellow solid in 81.2% yield.

Product mass spectrum (m/e): 1406.81, elemental analysis: theoretical value C, 85.37; h, 7.38; n, 4.98; o,2.27, found C, 85.36; h, 7.38; n, 4.96; o, 2.28.

Synthetic example 45: synthesis of Compound C201

The synthesis method is the same as that of the compound C59, the intermediate 21 is replaced by the intermediate 23(2.69g, 7mmol), and the carbazole is replaced by 3, 6-di-tert-butylcarbazole (8.38g, 30mmol), so that yellow solid C201 is obtained with the yield of 76.9%.

Product mass spectrum (m/e): 1422.79, elemental analysis: theoretical value C, 84.41; h, 7.30; n, 4.92; o, 1.12; s,2.25, found C, 84.39; h, 7.32; n, 4.90; o, 1.11; and S, 2.27.

Synthesis example 46: synthesis of Compound C202

The synthesis method is the same as that of the compound C59, the intermediate 21 is replaced by the intermediate 24(2.6g, 7mmol), and the carbazole is replaced by 3, 6-di-tert-butylcarbazole (8.38g, 30mmol), so that yellow solid C202 is obtained with the yield of 70.9%.

Product mass spectrum (m/e): 1470.74, elemental analysis C, 81.71; h, 7.06; n, 4.76; o, 1.09; se, 5.37: theoretical value C, 79.99; h, 3.85; n, 6.86; o, 1.57; se,7.73, found C, 81.72; h, 7.07; n, 4.78; o, 1.07; se, 5.35.

The technical effects and advantages of the invention are shown and verified by testing practical use performance by specifically applying the compound of the invention to an organic electroluminescent device.

An organic electroluminescent device includes an anode, a cathode, and an organic material layer between the two electrodes. The organic material may be divided into a plurality of regions, for example, the organic material layer may include a hole transport region, a light emitting layer, and an electron transport region.

As a material of the anode, an oxide transparent conductive material such as Indium Tin Oxide (ITO), Indium Zinc Oxide (IZO), tin dioxide (SnO2), or zinc oxide (ZnO), or any combination thereof can be used. The cathode may be made of magnesium (Mg), silver (Ag), aluminum (Al), aluminum-lithium (Al-Li), calcium (Ca), magnesium-indium (Mg-In), magnesium-silver (Mg-Ag), or any combination thereof.

The hole transport region is located between the anode and the light emitting layer. The hole transport region may be a Hole Transport Layer (HTL) of a single layer structure including a single layer containing only one compound and a single layer containing a plurality of compounds. The hole transport region may also be a multilayer structure including at least one of a Hole Injection Layer (HIL), a Hole Transport Layer (HTL), and an Electron Blocking Layer (EBL).

The material of the hole transport region may be selected from, but is not limited to, phthalocyanine derivatives such as CuPc, conductive polymers or polymers containing conductive dopants such as polyphenylenevinylene, polyaniline/dodecylbenzenesulfonic acid (Pani/DBSA), poly (3, 4-ethylenedioxythiophene)/poly (4-styrenesulfonate) (PEDOT/PSS), polyaniline/camphorsulfonic acid (Pani/CSA), polyaniline/poly (4-styrenesulfonate) (Pani/PSS), aromatic amine derivatives, and the like.

The light-emitting layer includes a light-emitting dye (i.e., dopant) that can emit different wavelength spectra, and may also include a Host material (Host). The light emitting layer may be a single color light emitting layer emitting a single color of red, green, blue, or the like. The single color light emitting layers of a plurality of different colors may be arranged in a planar manner in accordance with a pixel pattern, or may be stacked to form a color light emitting layer. When the light emitting layers of different colors are stacked together, they may be spaced apart from each other or may be connected to each other. The light-emitting layer may be a single color light-emitting layer capable of emitting red, green, blue, or the like at the same time.

The electron transport region may be an Electron Transport Layer (ETL) of a single-layer structure including a single-layer electron transport layer containing only one compound and a single-layer electron transport layer containing a plurality of compounds. The electron transport region may also be a multilayer structure including at least one of an Electron Injection Layer (EIL), an Electron Transport Layer (ETL), and a Hole Blocking Layer (HBL).

The preparation process of the organic electroluminescent device in the embodiment of the invention is as follows:

and sequentially depositing an anode, a hole transport layer, an organic light-emitting layer, an electron transport layer and a cathode on the substrate, and then packaging. Wherein, when the organic light-emitting layer is prepared, the organic light-emitting layer is formed by a method of co-evaporation of an electron donor type material source, an electron acceptor type material source and the deuterated TADF material source of the present invention.

The method specifically comprises the following steps:

1. the anode material coated glass plate was sonicated in a commercial detergent, rinsed in deionized water, washed in acetone: ultrasonically removing oil in an ethanol mixed solvent, baking in a clean environment until the water is completely removed, cleaning by using ultraviolet light and ozone, and bombarding the surface by using low-energy cationic beams;

2. placing the glass plate with the anode in a vacuum chamber, and vacuumizing to 1 × 10^-5～9×10^-3Pa, forming a hole injection layer by vacuum evaporation of a hole injection material on the anode layer film, wherein the evaporation rate is 0.1-0.5 nm/s;

3. vacuum evaporating hole transport material on the hole injection layer to form a hole transport layer with an evaporation rate of 0.1-0.5nm/s,

4. an organic light emitting layer of the device is vacuum evaporated on the hole transport layer, the organic light emitting layer material comprises a main body material and TADF dye, and the evaporation rate of the main body material and the evaporation rate of the dye are adjusted by a multi-source co-evaporation method to enable the dye to reach a preset doping proportion;

5. forming an electron transport layer on the organic light-emitting layer by vacuum evaporation of an electron transport material of the device, wherein the evaporation rate is 0.1-0.5 nm/s;

6. LiF is evaporated on the electron transport layer in vacuum at a speed of 0.1-0.5nm/s to serve as an electron injection layer, and an Al layer is evaporated on the electron transport layer in vacuum at a speed of 0.5-1nm/s to serve as a cathode of the device.

The embodiment of the invention also provides a display device which comprises the organic electroluminescent device provided as above. The display device can be specifically a display device such as an OLED display, and any product or component with a display function including the display device, such as a television, a digital camera, a mobile phone, a tablet computer, and the like. The display device has the same advantages as the organic electroluminescent device compared with the prior art, and the description is omitted here.

The organic electroluminescent device according to the invention is further illustrated by the following specific examples.

In the following embodiments of the present invention, the OLED includes an anode/a hole injection layer/a hole transport layer/a first exciton blocking layer/an emission layer/a second exciton blocking layer/an electron transport layer/an electron injection layer/a cathode, which are sequentially stacked. Wherein the anode is ITO; the hole injection layer is HATCN; the hole transport layer is NPB; the first exciton blocking layer is TCTA; the host material of the luminescent layer is TCTA and DCzPm co-evaporation host, wherein the thermal activation delayed fluorescence material (any one of C1-C96) is doped as luminescent dye, and the doping mass percentage concentration is 10%; the second exciton blocking layer is DCzPm; the electron transport layer is formed by co-evaporation of DPyPA and Liq; the electron injection layer is LiF; the cathode is Al.

Example 1

The glass plate coated with the ITO transparent conductive layer was sonicated in a commercial detergent, rinsed in deionized water, washed in acetone: ultrasonically removing oil in an ethanol mixed solvent, baking in a clean environment until the water is completely removed, cleaning by using ultraviolet light and ozone, and bombarding the surface by using low-energy cationic beams;

carrying out vacuum evaporation on the ITO transparent conductive layer to form HATCN serving as a hole injection layer of the device, wherein the evaporation rate is 0.1nm/s, and the total film thickness is 5 nm;

NPB is evaporated on the hole injection layer in vacuum to serve as a hole transport layer of the device, the evaporation rate is 0.1nm/s, and the total film thickness of evaporation is 30 nm;

evaporating TCAC on the hole transport layer in vacuum to be used as a first exciton blocking layer, wherein the evaporation rate is 0.1nm/s, and the total film thickness of the evaporation is 10 nm;

and (3) performing vacuum evaporation on the light-emitting layer of the device on the first exciton blocking layer, wherein the light-emitting layer comprises a host material and a dye material, the host material mCBP is adopted, and the thermal activation delayed fluorescence material C1 is adopted as the dye material. The evaporation rate of the main body material is adjusted to be 0.1nm/s, the evaporation rate of the dye in the luminescent layer is adjusted to be 30% of the evaporation rate of the main body, and the total thickness of the luminescent layer evaporation film is 30 nm;

DPyPA and Liq are subjected to vacuum co-evaporation on the luminescent layer to serve as electron transport materials of the device, the co-evaporation ratio is 1:1, the evaporation rate is 0.1nm/s, and the total film thickness of evaporation is 30 nm;

LiF with the thickness of 0.5nm is vacuum evaporated on the electron transport layer to be used as an electron injection layer, and an Al layer with the thickness of 150nm is used as a cathode of the device.

ITO/HATCN(5nm)/NPB(30nm)/TCTA(5nm)/mCBP(5nm)/mCBP:30wt％C1(30nm)/DPyPA:Liq(30nm)/LiF(0.5nm)/Al(150nm)。

Examples 2 to 20 are the same as those of example 1, except that the luminescent dye in the light emitting layer is replaced with the compound C1 of the present invention by the compounds C2, C3, C4, C5, C6, C7, C8, C9, C10, C11, C12, C13, C14, C15, C16, C17, C33, C49, and C65, respectively.

Comparative examples 1 to 7 were each the same as the preparation method of example 1 except that the luminescent dye in the light-emitting layer was replaced with the compound C1 of the present invention by the compounds EM-1 to EM-7 of the prior art, respectively.

The properties of the organic electroluminescent devices prepared in the above examples and comparative examples are shown in table 2 below:

table 2:

as can be seen from Table 2 above, when the compound of the present invention is used for a luminescent dye in a luminescent layer of an organic electroluminescent device, a luminance of 1000cd/m is required²When the material is used, the driving voltage is low below 3.81V, the current efficiency is as high as more than 21cd/A, the service life of the device is more than 48h, the driving voltage can be effectively reduced, the current efficiency is improved, and the material is an electron barrier material with good performance.

The molecular structure of the compound EM-1 used in the comparative example 1 is different from that of the compound C1 of the present invention used in the example 1 in terms of substituents at the cyano para position, and the carbazoles at the cyano para positions of the EM-1 and EM-2 used in the comparative example 1 and the EM-2 have been confirmed to have weaker carbon-nitrogen bond energy compared with the benzonitrile group used in the compound of the present invention, and at the same time, since the molecular weights of the materials are increased to a relatively large extent by the EM-1 and EM-2, which causes difficulty in evaporation of the two materials during the process of preparing the device, the experimental results show that the lifetime of the devices prepared in the comparative example 1 and the comparative example 2 is significantly shorter than that of the devices prepared in the example 1 of the present invention.

The compounds EM-3, EM-4 and EM-5 adopted in the comparative examples 3,4 and 5 have the molecules with groups (N-phenylcarbazole, spirofluorene, azaspirofluorene and the like) with larger steric hindrance introduced at the para-position of a cyano group, and the molecular structures can cause the groups to generate strong distortion and difficult to realize effective conjugation with the central benzene ring. Meanwhile, the compounds EM-3, EM-4 and EM-5 also have a problem of large molecular weight, resulting in poor evaporation properties, and the experimental results of table 2 show that the devices prepared in comparative examples 3,4 and 5 have lower luminous efficiency and device lifetime than those of the devices prepared in examples 1 to 20 using the compounds of the present invention. Therefore, the compound adopting the A-pi-A or A-pi-R structure has obvious structural advantages and better practical value.

Although the invention has been described in connection with the embodiments, the invention is not limited to the embodiments described above, and it should be understood that various modifications and improvements can be made by those skilled in the art within the spirit of the invention, and the scope of the invention is outlined by the appended claims.

It should be understood that the above examples are only for clarity of illustration and are not intended to limit the embodiments. Other variations and modifications will be apparent to persons skilled in the art in light of the above description. And are neither required nor exhaustive of all embodiments. And obvious variations or modifications therefrom are within the scope of the invention.