阅读说明：本技术 化合物与有机电致发光器件、显示装置 (Compound, organic electroluminescent device and display device ) 是由 霍学兵 王占奇 李志强 郭林林 丁言苏 陆金波 于 2021-07-12 设计创作，主要内容包括：本申请涉及电致发光领域,公开一种化合物与有机电致发光器件、显示装置。该化合物的结构式如式(Ⅰ)～(III)所示：使用本申请化合物的材料的有机电致发光器件具有较低的驱动电压、较高的电流效率和较长的使用寿命。(The application relates to the field of electroluminescence, and discloses a compound, an organic electroluminescent device and a display device. The structural formula of the compound is shown in formulas (I) to (III):)

1. A compound is characterized in that the structural formula of the compound is shown in formulas (I) to (III),

wherein m is an integer between 0 and 6, and n is an integer between 0 and 3;

R₁、R₂independently selected from alkyl containing 1-20 carbon atoms or aryl containing 6-40 carbon atoms; r₁And R₂Can be connected into a ring through a single bond;

R₃、R₄independently selected from deuterium, F, CN, alkyl containing 1-20 carbon atoms, alkoxy containing 1-20 carbon atoms or aryl containing 6-40 carbon atoms;

Ar₁、Ar₂each independently selected from hydrogen, an aryl group having 6 to 40 carbon atoms, formula (IV), an aryl group having 6 to 40 carbon atoms substituted by formula (IV), and Ar₁、Ar₂The aromatic hydrogen in (1) can be replaced by R;

in the formula (IV), X is selected from oxygen or sulfur, and Sp2 hybridized carbon atom participates in the connection in the formula (IV);

r is selected from deuterium, F, CN, alkyl containing 1-20 carbon atoms, alkoxy containing 1-20 carbon atoms or aryl containing 6-40 carbon atoms;

Ar₁、Ar₂not simultaneously selected from hydrogen.

2. The compound of claim 1, wherein the compound is selected from the structures:

3. a compound according to claim 2, wherein the sum of m and n is 0, 1 or 2.

4. A compound according to claim 3, wherein the sum of m and n is 0.

5. A compound according to any one of claims 1 to 4, wherein the aryl group having 6 to 40 carbon atoms is selected from one of benzene, biphenyl, naphthalene, anthracene, phenanthrene, fluoranthene, triphenylene, fluorene, spirofluorene, pyrene, benzanthracene, benzofluorene, naphthoanthracene, naphthofluorene, dibenzoanthracene, dibenzofluorene, hydrogenated benzanthracene, indenofluorene or benzoindenofluorene.

6. The compound of any one of claims 1 to 4, wherein the alkyl group having 1 to 20 carbon atoms is selected from one of a methyl group, an ethyl group, a propyl group, a butyl group, a pentyl group, and a hexyl group;

the alkoxy group having 1 to 20 carbon atoms is one selected from a methoxy group, an ethoxy group, a propoxy group, a butoxy group, a pentyloxy group and a hexyloxy group.

7. A compound according to any one of claims 1 to 4, wherein Ar is Ar₁、Ar₂Are not identical.

8. The compound of any one of claims 1-4, wherein the compound is selected from the group consisting of compounds of formula i-1 through formula i-60 and isomers thereof, compounds of formula II-1 through formula II-63 and isomers thereof, compounds of formula III-1 through formula III-63 and isomers thereof, thio compounds of formula i-34 through formula i-42 and isomers thereof, thio compounds of formula II-34 through formula II-42 and isomers thereof, and thio compounds of formula III-34 through formula III-42 and isomers thereof, wherein the compounds of formula i-1 through formula i-60 are represented by the following formula:

the compounds shown in the formulas II-1 to II-60 are respectively shown in the formulas I-1 to I-60Is replaced byThe resulting structure;

the compounds shown in the formulas III-1 to III-60 are respectively shown in the formulas I-1 to I-60Is replaced byThe resulting structure;

wherein x is the position where the structure shown is attached to the N atom.

9. An organic electroluminescent element comprising the compound according to any one of claims 1 to 8.

10. A display device characterized by comprising the organic electroluminescent device according to claim 9.

11. A process for the preparation of a compound as claimed in any one of claims 1 to 8, wherein the preparation of the compound of formula (i) comprises the steps of:

s11) reacting halogenated benzfluorene compound M1 with carbazole to generate an intermediate compound shown as a formula M1-1;

s12) carrying out halogenation reaction on the intermediate compound shown in the formula M1-1 to generate an intermediate compound shown in a formula M1-2 or a formula M1-3;

wherein X, Y are each independently selected from chlorine, bromine, or iodine, and the reactivity of X is greater than the reactivity of Y;

s13) reacting the intermediate compound of formula M1-2 with Ar-B (OH)₂Carrying out primary coupling reaction to form the compound shown in the formula (I);

or, the intermediate compound shown as the formula M1-3 and Ar-B (OH)₂Carrying out primary coupling reaction to form an intermediate compound shown as a formula M1-4; reacting the intermediate compound shown as the formula M1-4 with Ar-B (OH)₂Carrying out secondary coupling reaction to form the compound shown in the formula (I);

ar is selected from Ar₁And/or Ar₂；

The preparation of the compound shown in the formula (II) comprises the following steps:

s21) reacting halogenated benzfluorene compound M1 with carbazole to generate an intermediate compound shown as a formula M2-1;

s22) carrying out halogenation reaction on the intermediate compound shown in the formula M2-1 to generate an intermediate compound shown in a formula M2-2 or a formula M2-3;

s23) reacting the intermediate compound of formula M2-2 with Ar-B (OH)₂Carrying out primary coupling reaction to form the compound shown in the formula (II);

or, the intermediate compound shown as the formula M2-3 and Ar-B (OH)₂Carrying out primary coupling reaction to form an intermediate compound shown as a formula M2-4; reacting the intermediate compound shown as the formula M2-4 with Ar-B (OH)₂Carrying out secondary coupling reaction to form the compound shown in the formula (II);

the preparation of the compound shown in the formula (III) comprises the following steps:

s31) reacting halogenated benzfluorene compound M1 with carbazole to generate an intermediate compound shown as a formula M3-1;

s32) carrying out halogenation reaction on the intermediate compound shown in the formula M3-1 to generate an intermediate compound shown in a formula M3-2 or a formula M3-3;

s33) reacting the intermediate compound of formula M3-2 with Ar-B (OH)₂Carrying out primary coupling reaction to form the compound shown in the formula (III);

or, the intermediate compound shown as the formula M3-3 and Ar-B (OH)₂Carrying out primary coupling reaction to form an intermediate compound shown as a formula M3-4; reacting the intermediate compound shown as the formula M3-4 with Ar-B (OH)₂Carrying out secondary coupling reaction to form the compound shown in the formula (III);

the intermediate compounds shown as the formulas M2-1-M2-4 are intermediate compounds shown as the formulas M1-1-M1-4 respectivelyIs replaced byThe resulting structure;

the intermediate compounds shown as the formulas M3-1-M3-4 are intermediate compounds shown as the formulas M1-1-M1-4 respectivelyIs replaced byThe resulting structure.

12. An intermediate compound in the preparation method of claim 11, wherein the intermediate compound has a structure represented by formula M1-1-M1-4, formula M2-1-M2-4, or formula M3-1-M3-4.

Technical Field

The application relates to the field of electroluminescence, in particular to a compound consisting of benzofluorene and carbazole, an organic electroluminescent device and a display device.

Background

Currently, organic electroluminescent (OLED) display technology has been applied in the fields of smart phones, tablet computers, and the like, and further will be expanded to large-size application fields such as televisions. In the development process of the last 30 years, various OLED materials with excellent performance are developed, and the commercialization process of the OLED is accelerated by different designs of the device structure and optimization of the device life, efficiency and other properties, so that the OLED is widely applied in the fields of display and illumination.

However, since there is a great gap between the external quantum efficiency and the internal quantum efficiency of the OLED, the development of the OLED is greatly restricted, and one of the most important factors is that the efficiency of the device still does not reach a desired level. This is because most of light is confined inside the light emitting device due to mode loss of the substrate, loss of surface plasmon, and waveguide effect, thereby reducing the light emitting efficiency of the device. Improving the light emitting efficiency of the device, and using light extraction materials is one of the effective methods. The light extraction Layer (CPL) can adjust the light extraction direction and the light extraction efficiency by reducing the surface plasma effect of the metal electrode, and can effectively improve the light extraction efficiency of the device, thereby improving the luminous efficiency of the device. At present, the light extraction material is of a single type and has an unsatisfactory effect, and developing a more effective light extraction material is one of the more serious challenges facing OLED workers.

In addition, the selection of the materials of the light emitting layer and other organic functional layers also has a great influence on the current efficiency and driving voltage of the device, and functional layer materials with higher performance are still being explored.

Therefore, in order to meet the higher requirements of people for OLED devices, the development of more various and higher-performance OLED materials is urgently needed in the art.

Disclosure of Invention

The application discloses a compound consisting of benzofluorene and carbazole, an organic electroluminescent device and a display device.

In order to achieve the purpose, the application provides the following technical scheme:

a compound has a structural formula shown in formulas (I) to (III),

wherein m is an integer between 0 and 6, and n is an integer between 0 and 3;

R₁、R₂independently selected from alkyl containing 1-20 carbon atoms or aryl containing 6-40 carbon atoms; r₁And R₂Can be connected into a ring through a single bond;

R₃、R₄independently selected from deuterium, F, CN, alkyl containing 1-20 carbon atoms, alkoxy containing 1-20 carbon atoms or aryl containing 6-40 carbon atoms;

Ar₁、Ar₂each independently selected from hydrogen, an aryl group having 6 to 40 carbon atoms, formula (IV), an aryl group having 6 to 40 carbon atoms substituted by formula (IV), and Ar₁、Ar₂The aromatic hydrogen in (1) can be replaced by R;

in the formula (IV), X is selected from oxygen or sulfur, and Sp2 hybridized carbon atom participates in the connection in the formula (IV);

r is selected from hydrogen, deuterium, F, CN, alkyl containing 1-20 carbon atoms, alkoxy containing 1-20 carbon atoms or aryl containing 6-40 carbon atoms;

Ar₁、Ar₂are not simultaneously selectedFrom hydrogen.

Further, the compound is selected from the following structures:

further, the sum of m and n is 0, 1 or 2.

Further, the sum of m and n is 0.

Further, the aryl group having 6 to 40 carbon atoms is selected from one of benzene, biphenyl, naphthalene, anthracene, phenanthrene, fluoranthene, triphenylene, fluorene, spirofluorene, pyrene, benzanthracene, benzofluorene, naphthoanthracene, naphthofluorene, dibenzanthracene, dibenzofluorene, hydrogenated benzanthracene, indenofluorene or benzoindenofluorene.

Further, the alkyl containing 1-20 carbon atoms is selected from one of methyl, ethyl, propyl, butyl, pentyl or hexyl;

the alkoxy group having 1 to 20 carbon atoms is one selected from a methoxy group, an ethoxy group, a propoxy group, a butoxy group, a pentyloxy group and a hexyloxy group.

Further, Ar₁、Ar₂Are not identical.

Further, the compound is selected from one of a compound shown in a formula I-1-formula I-60 and an isomer thereof, a compound shown in a formula II-1-formula II-63 and an isomer thereof, a compound shown in a formula III-1-formula III-63 and an isomer thereof, a thio compound of a compound shown in a formula I-34-formula I-42 and an isomer thereof, a thio compound of a compound shown in a formula II-34-formula II-42 and an isomer thereof, or a thio compound of a compound shown in a formula III-34-formula III-42 and an isomer thereof, wherein the compound shown in the formula I-1-formula I-60 is shown as follows:

the compounds shown in the formulas II-1 to II-60 are respectively shown in the formulas I-1 to I-60Is replaced byThe resulting structure;

the compounds shown in the formulas III-1 to III-60 are respectively shown in the formulas I-1 to I-60Is replaced byThe resulting structure;

wherein x is the position where the structure shown is attached to the N atom.

Among the compounds represented by the formulae II-1 to II-60, the compound represented by the formula I-1 is exemplified by the formula II-1Is replaced byThe resulting structure of formula II-1 is then as follows:

among the compounds represented by the formulae III-1 to III-60, the compound represented by the formula I-1 is exemplified by the formula III-1Is replaced byThe resulting structure of formula III-1 is then as follows:

in the compounds represented by the formulas I-1 to I-60, II-1 to II-63 and III-1 to III-63, Ar₁、Ar₂A specific position on the aromatic ring is linked to a carbazole ring when constituting Ar₁、Ar₂When the group (b) is two or more aromatic groups, the linkage therebetween is also fixed.

In the present application, the isomers of the compounds represented by the formulae I-1 to I-60, the isomers of the compounds represented by the formulae II-1 to II-63, and the isomers of the compounds represented by the formulae III-1 to III-63 can be understood as follows: composition Ar₁、Ar₂Any possible linkage of radicals, and Ar₁、Ar₂Any possible position on the aromatic ring is linked to the carbazole ring, and the resulting structure, as long as the aromatic system participating in conjugation is not reduced in the original structure, is referred to as an isomer of the compound, and is included in the scope of the present application.

For example, compound I-6, the isomers can be represented by the following structural formula:

but in the case of the compound I-4,

the following structures, because of the reduced conjugation system, are not referred to as isomers:

thio in the sense of the present application means a compound in which one or 2O in the corresponding compound is replaced by S, as illustrated below:

the thio structure of compounds I-35 may include, for example:

the present application also provides an organic electroluminescent device comprising a compound as described herein.

The application also provides a display device comprising the organic electroluminescent device provided by the application.

The present application also provides a process for the preparation of a compound as described above, said process comprising the steps of:

s11) reacting halogenated benzfluorene compound M1 with carbazole to generate an intermediate compound shown as a formula M1-1;

s12) carrying out halogenation reaction on the intermediate compound shown in the formula M1-1 to generate an intermediate compound shown in a formula M1-2 or a formula M1-3;

wherein X, Y are each independently selected from chlorine, bromine or iodine, X, Y are the same or different;

when X, Y is different, when M1-3 is prepared, the synthetic method is schematically as follows:

s13) reacting the intermediate compound of formula M1-2 with Ar-B (OH)₂Carrying out primary coupling reaction to form the compound shown in the formula (I);

in the formula (I), when Ar₁And Ar₂One of them is selected from H, an intermediate compound represented by M1-2 and Ar-B (OH)₂Reacting to generate a compound shown in a formula (I); in the formula (I), when Ar₁And Ar₂Are not all selected from H, and Ar₁And Ar₂When the same, an intermediate compound represented by M1-3 and Ar-B (OH)₂Reacting to generate a compound shown in a formula (I);

the reaction process may be, for example:

in addition to the above formation modes, Ar₁And Ar₂In the absence of a catalyst, reacting the intermediate compound of formula M1-3 with Ar-B (OH)₂Carrying out primary coupling reaction to form an intermediate compound shown as a formula M1-4; reacting the intermediate compound shown as the formula M1-4 with Ar-B (OH)₂Carrying out secondary coupling reaction to form the compound shown in the formula (I); ar is selected from Ar₁And/or Ar₂；

The reaction process may be, for example:

wherein when X is selected from chlorine, Y is selected from bromine and iodine; when X is selected from bromine, Y is selected from iodine, and when X, Y is the same, Ar-B (OH) can be controlled₂In an amount to prepare the compound of formula (I).

The preparation of the compound shown in the formula (II) comprises the following steps:

s21) reacting halogenated benzfluorene compound M1 with carbazole to generate an intermediate compound shown as a formula M2-1;

s22) carrying out halogenation reaction on the intermediate compound shown in the formula M2-1 to generate an intermediate compound shown in a formula M2-2 or a formula M2-3;

s23) reacting the intermediate compound of formula M2-2 with Ar-B (OH)₂Carrying out primary coupling reaction to form the compound shown in the formula (II);

or, the intermediate compound shown as the formula M2-3 and Ar-B (OH)₂Carrying out primary coupling reaction to form an intermediate compound shown as a formula M2-4; reacting the intermediate compound shown as the formula M2-4 with Ar-B (OH)₂Carrying out secondary coupling reaction to form the compound shown in the formula (II);

the preparation of the compound shown in the formula (III) comprises the following steps:

s31) reacting halogenated benzfluorene compound M1 with carbazole to generate an intermediate compound shown as a formula M3-1;

s32) carrying out halogenation reaction on the intermediate compound shown in the formula M3-1 to generate an intermediate compound shown in a formula M3-2 or a formula M3-3;

s33) reacting the intermediate compound of formula M3-2 with Ar-B (OH)₂Carrying out primary coupling reaction to form the compound shown in the formula (III);

or, the intermediate compound shown as the formula M3-3 and Ar-B (OH)₂Carrying out primary coupling reaction to form an intermediate compound shown as a formula M3-4; reacting the intermediate compound shown as the formula M3-4 with Ar-B (OH)₂Carrying out secondary coupling reaction to form the compound shown in the formula (III).

The intermediate compounds shown as the formulas M2-1-M2-4 are intermediate compounds shown as the formulas M1-1-M1-4 respectivelyIs replaced byThe resulting structure; the intermediate compounds shown as the formulas M3-1-M3-4 are intermediate compounds shown as the formulas M1-1-M1-4 respectivelyIs replaced byThe resulting structure.

The application also provides an intermediate compound in the preparation method, wherein the intermediate compound has a structure shown in a formula M1-1-M1-4, a formula M2-1-M2-4 or a formula M3-1-M3-4.

By adopting the technical scheme of the application, the beneficial effects are as follows:

the compounds shown in formulas (I) to (III) are novel compounds, and can be used for organic electroluminescent devices and used as HTL and Host materials. In addition, the OLED device prepared by the compound material has the advantages of low driving voltage, high luminous efficiency and long service life.

Detailed Description

The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the embodiments of the present application, and it is obvious that the described embodiments are only a part of the embodiments of the present application, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present application.

It should be noted that: in the present application, all embodiments and preferred methods mentioned herein can be combined with each other to form new solutions, if not specifically stated. In the present application, all the technical features mentioned herein as well as preferred features may be combined with each other to form new technical solutions, if not specifically stated. In the present application, percentages (%) or parts refer to percent by weight or parts by weight relative to the composition, unless otherwise specified. In the present application, the components referred to or the preferred components thereof may be combined with each other to form new embodiments, if not specifically stated. In this application, unless otherwise stated, the numerical range "a-b" represents a shorthand representation of any combination of real numbers between a and b, where a and b are both real numbers. For example, a numerical range of "6 to 22" means that all real numbers between "6 to 22" have been listed herein, and "6 to 22" is simply a shorthand representation of the combination of these values. The "ranges" disclosed herein may be in the form of lower limits and upper limits, and may be one or more lower limits and one or more upper limits, respectively. In the present application, unless otherwise indicated, the individual reactions or process steps may or may not be performed in sequence. Preferably, the reaction processes herein are carried out sequentially.

Unless otherwise defined, technical and scientific terms used herein have the same meaning as is familiar to those skilled in the art. In addition, any methods or materials similar or equivalent to those described herein can also be used in the present application.

Synthesis examples:

and (3) synthesis of an intermediate:

synthesis of M1-1:

a 250 ml three-neck flask, under the protection of nitrogen, adding 60 ml of dried toluene, 3.23 g (0.01mol) of 9-bromo-7, 7-dimethyl-7H-benzo [ c ] fluorene, 1.67 g (0.01mol) of carbazole, 0.0575 g (0.0001mol) of Pd (dba)2 (bis (dibenzylidene acetone palladium), 0.4 g (0.0002mol) of toluene solution containing 10% of tri-tert-butylphosphine, 1.44 g (0.015mol) of sodium tert-butoxide, heating to reflux for 4 hours, cooling, adding water for liquid separation, washing an organic layer to be neutral, drying magnesium sulfate, filtering to remove magnesium sulfate, concentrating to be dry, and recrystallizing by using a mixed solvent of methanol and toluene to obtain 3.1 g of the compound represented by the formula M1-1.

Mass spectrometric detection of a compound of formula M1-1 determined to have a molecule M/z: 409.

synthesis of M1-2

Adding 4.09 g (0.01mol) of a compound shown as M1-1 and 100 ml of DMF (dimethyl formamide) into a 250 ml three-neck flask, controlling the temperature to be 20-25 ℃, adding 1.78 g (0.01mol) of NBS (N-bromosuccinimide) in batches, controlling the temperature to be 20-25 ℃ after the addition, reacting for 12 hours, cooling, adding water, and filtering to obtain a solid. The solid was dried, separated by column chromatography on silica gel and eluted with petroleum ether to give 3.9 g of a compound represented by M1-2.

Performing mass spectrum detection on the compound shown as the formula M1-2, wherein two maximum M/z peaks are 487 and 489, and the molecular formula is determined to be C₃₁H₂₂BrN。

Synthesis of M1-3A

Referring to the synthesis of M1-2, except that the amount of NBS substance therein was changed to 2.2 times as much as that of the compound represented by M1-1, the compound represented by M1-3A was obtained.

Performing mass spectrometric detection on a compound shown as a formula M1-3A, wherein M/z is 567, and the molecular formula is determined to be C₃₁H₂₁Br₂N。

Synthesis of M1-3B

Adding 4.88 g (0.01mol) of a compound shown as M1-2 and 100 ml of DMF (dimethyl formamide) into a 250 ml three-neck flask, controlling the temperature to be 35-45 ℃, adding 2.25 g (0.01mol) of NIS (N-iodosuccinimide) in batches, controlling the temperature to be 35-45 ℃ after the addition to react for 4 hours, and then heating to 60-70 ℃ to react for 2 hours. Cooling, adding water, and filtering to obtain solid. The solid was dried, separated by column chromatography on silica gel and eluted with petroleum ether to give 5.1 g of a compound represented by M1-3B.

Performing mass spectrometric detection on the compound shown as the formula M1-3B, wherein the two maximum M/z peaks are 613 and 615, and the molecular formula is determined to be C₃₁H₂₁BrIN。

With reference to the above synthetic methods, the following intermediates were synthesized:

synthesis example of the final product:

synthesis example 1 Synthesis of Compound I-1

A 250 ml three-neck flask, under the protection of nitrogen, adding 40 ml of toluene, 20 ml of ethanol and 20 ml of water, then adding 4.88 g (0.01mol) of the compound represented by M1-2, 1.22 g (0.01mol) of phenylboronic acid, 2.12 g (0.02mol) of sodium carbonate and 0.115 g (0.0001mol) of palladium tetratriphenylphosphine, slowly heating to reflux reaction for 8 hours, cooling, adding water for liquid separation, washing an organic layer with water, drying magnesium sulfate, filtering to remove the magnesium sulfate, removing the solvent under reduced pressure, and recrystallizing the obtained solid with a mixed solvent of ethanol and toluene to obtain 4.1 g of the compound represented by the formula I-1.

Performing mass spectrum detection on the compound shown in the formula I-1, and determining that the molecular m/z is as follows: 485.

the compound shown in the formula I-1 is subjected to nuclear magnetic detection, and the data are analyzed as follows: 1H-NMR (Bruker, Switzerland, Avance II 400MHz NMR spectrometer, CDCl3), delta 8.88(m, 1H), delta 8.56(m, 1H), delta 8.36(d, 1H), delta 8.27(d, 1H), delta 8.20(d, 1H), delta 8.17(m, 1H), delta 7.78-7.73 (m, 3H), delta 7.62(m, 1H), delta 7.60(d, 1H), delta 7.53-7.46 (m, 4H), delta 7.40(m, 1H), delta 7.31-7.22 (m, 2H), delta 7.17(m, 1H), delta 7.13-7.07 (m, 2H), delta 1.77(s, 6H).

Synthesis example 2 Synthesis of Compound I-7

Referring to the synthesis of Compound I-1, except that phenylboronic acid was replaced with triphenyleneboronic acid, the compound of formula I-7 was obtained.

Performing mass spectrum detection on the compound shown in the formula I-7, and determining that the molecular m/z is as follows: 635.

synthesis example 3 Synthesis of Compound I-11

Referring to the synthesis of compound I-1, except that phenylboronic acid therein was replaced with 9, 9-diphenyl-9H-fluorene-2-boronic acid, the compound represented by formula I-11 was obtained.

Performing mass spectrum detection on the compound shown in the formula I-11, and determining that the molecular m/z is as follows: 725.

synthesis example 4 Synthesis of Compound I-21

Referring to the synthesis of compound 1, except that M1-2 was changed to a compound represented by M1-3A, phenylboronic acid was changed to 9, 9-dimethyl-9H-fluorene-2-boronic acid, and the amount of 9, 9-dimethyl-9H-fluorene-2-boronic acid was 2.2 times that of M1-2, the compound represented by formula I-21 was obtained.

Performing mass spectrometric detection on the compound shown as the formula I-21, and determining the molecular m/z as follows: 793.

synthesis example 5 Synthesis of Compound I-26

Synthesis of intermediate M1-4

A 250 ml three-neck flask, under the protection of nitrogen, adding 40 ml of toluene, 20 ml of ethanol and 20 ml of water, then adding 6.14 g (0.01mol) of a compound shown as M1-3B, 2.38 g (0.01mol) of 9, 9-dimethyl-9H-fluorene-2-boric acid, 2.12 g (0.02mol) of sodium carbonate and 0.115 g (0.0001mol) of tetratriphenylphosphine palladium, slowly heating to 60 ℃, reacting for 12 hours, cooling, adding water for liquid separation, washing an organic layer with water, drying magnesium sulfate, filtering to remove the magnesium sulfate, removing the solvent under reduced pressure, separating the obtained solid by chromatography, eluting with petroleum ether, and obtaining 5.2 g of an intermediate shown as a formula M1-4.

Performing mass spectrum detection on the intermediate shown in the formula M1-4, determining that the two peaks with the maximum M/z are 681 and 679, and determining that the molecular formula is C₄₆H₃₄BrN。

Synthesis of Compound I-26

Synthesis of reference Compound I-1, except that M1-2 was replaced with an intermediate represented by M1-4 to give a compound represented by the formula I-26.

Performing mass spectrometric detection on the compound shown as the formula I-26, and determining the molecular m/z as follows: 677.

synthesis example 6 Synthesis of Compound I-30

Referring to the synthesis method of the compound I-26, the compound M1-3B reacts with triphenyleneboronic acid and 2-naphthalene boronic acid in sequence to prepare the compound I-30.

Performing mass spectrometric detection on the compound shown as the formula I-30, and determining the molecular m/z as follows: 761.

synthesis example 7 Synthesis of Compound I-34

With reference to the synthesis of compound I-21, 9-dimethyl-9H-fluorene-2-boronic acid was replaced with dibenzo [ b, d ] furan-3-boronic acid to give the compound of formula I-34.

Performing mass spectrometric detection on the compound shown as the formula I-34, and determining the molecular m/z as follows: 741.

synthesis example 8 Synthesis of Compound I-40

Referring to the synthesis of Compound I-1, except that phenylboronic acid was replaced with (6-phenylbis [ b, d ] furan-4-yl) boronic acid, the compound of formula I-40 was obtained.

Performing mass spectrum detection on the compound shown in the formula I-40, and determining that the molecular m/z is as follows: 651.

synthesis example 9 the following compounds were synthesized with reference to the above examples and detected by mass spectrometry:

synthesis example 10 Synthesis of Compound I-52

Referring to the synthesis of compound I-21, except that M1-3A was changed to the compound represented by I-52-3 and 9, 9-dimethyl-9H-fluorene-2-boronic acid was changed to phenylboronic acid, the compound represented by formula I-52 was obtained.

Performing mass spectrometric detection on the compound shown as the formula I-52, and determining the molecular m/z as follows: 685.

materials used in device examples:

synthesis of HT-2

Synthesis method reference is made to the synthesis of M1-1 except that 9-bromo-7, 7-dimethyl-7H-benzo [ c ] fluorene therein is replaced by 5-bromo-7, 7-dimethyl-7H-benzo [ c ] fluorene and carbazole therein is replaced by 3- (triphenylen-2-yl) -9H-carbazole to give HT-2.

Mass spectrometric detection of a compound of formula HT-2, the molecule m/z is determined as: 635.

synthesis of HT-3

(1) Synthesis of 3-bromo-9- (9, 9-dimethyl-9H-fluoren-2-yl) -6-phenyl-9H-carbazole

Synthetic method reference is made to the synthesis of M1-2 except that M1-1 therein is replaced by 9- (9, 9-dimethyl-9H-fluoren-2-yl) -3-phenyl-9H-carbazole to give 3-bromo-9- (9, 9-dimethyl-9H-fluoren-2-yl) -6-phenyl-9H-carbazole.

The mass spectrum detection is carried out on the 3-bromine-9- (9, 9-dimethyl-9H-fluorene-2-yl) -6-phenyl-9H-carbazole, the two peaks with the maximum m/z are 513 and 515, and the molecular formula is determined to be C₃₃H₂₄BrN。

(2) Synthesis of HT-3

The synthesis method refers to the synthesis of the compound I-1, except that M1-2 is replaced by 3-bromo-9- (9, 9-dimethyl-9H-fluoren-2-yl) -6-phenyl-9H-carbazole, and phenylboronic acid is replaced by 9, 9-dimethyl-9H-fluoren-2-boronic acid, so as to obtain the compound shown in HT-3.

The mass spectrometric detection of HT-3 was carried out at m/z 627.

Synthesis of PH-1

Referring to the synthesis of compound I-1, except that M1-2 was replaced with 4-bromo-6-phenyldibenzo [ b, d ] furan and phenylboronic acid was replaced with (9- (9, 9-dimethyl-9H-furan-2-yl) -9H-carbazol-3-yl) boronic acid to give the compound shown at pH-1.

The detection was carried out by mass spectrometry at pH-1, with m/z being 601.

Device example 1

In the examples, the compound of the present application was used as a hole transport material in an organic electroluminescent device, and in the comparative examples, HT-1 to HT-4 and PH-1 were used as a hole transport material in an organic electroluminescent device.

The organic electroluminescent device has the following structure: ITO/HIL02(100 nm)/hole transport material (40nm)/EM1(30nm)/Alq3(30nm)/LiF (0.5nm)/Al (150 nm).

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

carrying out ultrasonic treatment on the glass substrate coated with the ITO transparent conductive layer (serving as an anode) in a cleaning agent, then washing the glass substrate in deionized water, ultrasonically removing oil in a mixed solvent of acetone and ethanol, baking the glass substrate in a clean environment until the water is completely removed, cleaning the glass substrate by using ultraviolet light and ozone, and bombarding the surface by using low-energy cation beams to improve the surface property and improve the binding capacity with a hole injection layer;

placing the glass substrate in a vacuum chamber, and vacuumizing to 1 × 10^-5～9×10^-3Pa, performing vacuum evaporation on the anode to form HIL02 as a hole injection layer, wherein the evaporation rate is 0.1nm/s, and the evaporation film thickness is 100 nm;

respectively carrying out vacuum evaporation on the compound and the contrast material on the hole injection layer to form a hole transport layer, wherein the evaporation rate is 0.1nm/s, and the evaporation film thickness is 40 nm;

vacuum evaporating EM1 on the hole transport layer to serve as an organic light emitting layer of the device, wherein the evaporation rate is 0.1nm/s, and the total film thickness is 30 nm;

vacuum evaporating Alq3 on the organic light-emitting layer to be used as an electron transport layer of the organic electroluminescent device; the evaporation rate is 0.1nm/s, and the total film thickness of the evaporation is 30 nm;

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

The luminance, driving voltage, and current efficiency of the prepared organic electroluminescent device were measured.

The organic electroluminescent device properties are shown in table 1 below. And testing by using an OLED-1000 multichannel accelerated aging life and light color performance analysis system produced in Hangzhou distance.

TABLE 1

Hole transport material	Required luminance cd/m2	Drive voltage V	Current efficiency cd/A
				HT-1	1000	5.16	1.55
HT-2	1000	4.98	1.66
				HT-3	1000	4.89	1.69
HT-4	1000	5.52	1.33
				PH-1	1000	5.09	1.58
Compound I-1	1000	4.66	1.65
				Compound I-7	1000	4.38	1.88
Compound I-11	1000	4.51	1.89
				Compound I-21	1000	4.44	1.91
Compound I-26	1000	4.31	1.77
				Compound I-30	1000	4.48	1.92
Compound I-34	1000	4.01	1.88
				Compound I-40	1000	3.97	1.89
Compound I-43	1000	4.45	1.86
				Compound I-44	1000	4.38	1.71
Compound I-45	1000	4.36	1.79
				Compound I-46	1000	4.49	1.88
Compound II-7	1000	4.40	1.96
				Compound III-7	1000	4.36	1.87
Compound II-40	1000	3.89	1.85
				Compound III-40	1000	3.92	1.82
Compound I-52	1000	4.55	1.79

As can be seen from the data in Table 1, the compound I-1 has no significant improvement in current efficiency as compared with the comparative material because of its smaller molecular weight, and the other compounds have better effects as compared with the comparative material.

Wherein, the compound I-34, the compound I-40 and the compound II-40, and the compound III-40 greatly improve the current efficiency and obviously reduce the voltage.

Device example 2

In the examples, the compound of the present application was used as the red host material in the organic electroluminescent device, and in the comparative examples, PH-1 was used as the red host material in the organic electroluminescent device.

The structure of the organic electroluminescent device is as follows: ITO/NPB (20 nm)/Red host material (35 nm): ir (piq)3[ 10% ]/TPBI (10nm)/Alq3(15nm)/LiF (0.5nm)/Al (150 nm). Wherein "Ir (piq)3[ 10% ]" refers to the doping ratio of the red dye, i.e. the weight portion ratio of the red host material to Ir (piq)3 is 100: 10.

The preparation process of the organic electroluminescent device is as follows: 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;

placing the glass substrate with the anode in a vacuum chamber, and vacuumizing to 1 × 10^-5～9×10^-3Pa, vacuum evaporating a hole transport layer NPB on the anode layer film, wherein the evaporation rate is 0.1nm/s, and the evaporation film thickness is 20 nm;

vacuum evaporating a red light main material and a dye Ir (piq)3 on the hole transport layer to be used as a light emitting layer of the organic electroluminescent device, wherein the evaporation rate is 0.1nm/s, and the total film thickness of the evaporation is 35 nm; (ii) a

Sequentially vacuum evaporating an electron transport layer TPBI and an electron transport layer Alq3 on the light-emitting layer, wherein the evaporation rates are both 0.1nm/s, and the evaporation film thicknesses are respectively 10nm and 15 nm;

and (3) evaporating LiF with the thickness of 0.5nm and Al with the thickness of 150nm on the electron transport layer in vacuum to be used as an electron injection layer and a cathode.

All the organic electroluminescent devices are prepared by the method, and the differences only lie in the selection of red light main body materials, and the details are shown in the following table 2.

And (3) performance testing:

the brightness, driving voltage, current efficiency and LT95 of the prepared organic electroluminescent device were measured by using Hangzhou remote production OLED-1000 multichannel accelerated aging life and photochromic performance analysis system test. LT95 indicates the time required for the luminance to drop to 95% of the initial luminance by measuring the current density at 1000cd/m2 and keeping the current density constant, and the test results are shown in the following table.

TABLE 2

As can be seen from the above table, compared to the comparative compound, the compound provided by the present application as the red host material of the organic electroluminescent device can improve the light emitting efficiency and reduce the driving voltage.

The device lifetime is particularly improved for compounds II-7 and III-7.

For the compounds I-34, I-40, II-40 and III-40, the voltage, the efficiency and the service life of the device are greatly improved.

It will be apparent to those skilled in the art that various changes and modifications may be made in the embodiments of the present application without departing from the spirit and scope of the application. Thus, if such modifications and variations of the present application fall within the scope of the claims of the present application and their equivalents, the present application is intended to include such modifications and variations as well.