CN102372665B - A kind of aryl fluorene compound and application - Google Patents

Abstract

The invention provides an arylfluorene compound and its application. The compound has a symmetrical structure, stable properties, simple preparation process, high luminous efficiency and high carrier mobility, and can be used for electron transport of electroluminescent elements. layer. The applied device can significantly reduce the driving voltage and improve the current efficiency. The general structural formula of the compound is shown in the following formula I: wherein, the core is selected from 9,9-disubstituted fluorene substituted by 2,7 diphenyl, and the 9-position substitution of fluorene can be an alkyl or aryl group; the terminal group Ar It is selected from pyridyl group, phenyl group, biphenyl group or naphthyl group; R is an alkyl group with 1-12 carbon atoms or an aryl group with 6-30 carbon atoms.

Description

A kind of aryl fluorene compound and application

technical field

The invention relates to a novel organic compound and its application in the technical field of organic electroluminescence display.

Background technique

An ideal electron transport material should have the following characteristics: reversible electrochemical reduction reaction; appropriate HOMO and LUMO energy levels; high electron mobility; good film-forming properties; high Tg; preferably able to block holes. In terms of compound structure, it is required that the molecules contain electron-deficient structural units and have good ability to accept electrons; the molecular weight is appropriate, which can not only ensure a higher glass transition temperature but also facilitate vacuum evaporation to form a film.

Generally speaking, electron transport materials are planar aromatic compounds with large conjugated structures. There are not many known electron transport materials with good performance. Currently available electron transport materials mainly include 8-hydroxyquinoline aluminum compounds , oxadiazole compounds, quinoxaline compounds, nitrile-containing polymers, other nitrogen-containing heterocyclic compounds, etc. (Chem.Mater.2004,16,4556-4573, J Mater.Chem.2005,15,94 -106).

Some polymers containing fluorene units have higher glass transition temperatures and electron transport properties (Chem. Mater. The method of painting. Here we have prepared a new class of compounds containing fluorene groups. They have symmetrical structures, high solubility, simple preparation process, small molecular weight and high glass transition temperature, and can form uniform non-crystalline films in vacuum evaporation. , more suitable for electroluminescent display devices.

Contents of the invention

The purpose of the present invention is to propose a novel compound which can be used in the field of organic electroluminescence display.

The rigid planar structure of fluorene derivatives can provide high electron mobility, and connecting phenyl groups to its two ends can not only effectively transfer electrons, but also reduce the coplanarity of the entire compound. From the perspective of the correlation between the structure and properties of materials, the introduction of electron-withdrawing groups into the conjugated system can better improve the electron transport properties of the compound. Phenyl groups, biphenyl groups, pyridyl groups and naphthyl groups all have electron-withdrawing properties. Connecting them to phenylfluorenyl groups can improve the carrier mobility of the compound and make the compound more effective. Good electron transport properties. At the same time, the introduction of substituents at the 9 and 9 positions of fluorene not only improves the stability of the compound, but also reduces the planarity of the entire molecule to a certain extent, thereby improving its film-forming properties. The compound has better stability in the air and can be used in organic electroluminescent devices.

The invention develops a novel organic compound, which has simple and easy preparation process, good thermal stability and high electron mobility, and can be used in organic electroluminescent devices.

The present invention discloses a class of novel compounds, the general structural formula of which is as follows:

Wherein Ar is selected from pyridyl group, phenyl group, biphenyl group or naphthyl group; R is an alkyl group with 1-12 carbon atoms or an aryl group with 6-30 carbon atoms.

When R in formula I is an alkyl group, it can be selected from methyl, ethyl, propyl, isopropyl, butyl, isobutyl, n-pentyl, n-hexyl, heptyl, octyl, nonyl, decyl, Undecyl, dodecyl, etc.; when R is aryl, it can be selected from phenyl, biphenyl, naphthyl, anthracenyl, fluoranthenyl, phenanthrenyl, indenyl, pyrenyl, perylenyl, etc.

The specific structure of Ar in the above formula I is selected from the following formulas II, III, IV, V, VI, VII, VIII or IX:

In order to illustrate the contents of the present invention more clearly, the following specifically describes the structures of the compounds involved in the present invention (take R as an example of methyl, phenyl, and p-tolyl, and other substituted 9,9-disubstituted fluorenes are connected in the same way):

The organic materials of the invention are used as electron transport layers in organic electroluminescent devices.

The present invention also proposes an organic electroluminescent device, wherein the organic functional layer includes the compound of the above general formula, and this type of compound is used as an electron transport material in the organic functional layer.

The organic material of the invention has a simple preparation process, high stability and high electron mobility, and can be used as an electron transport layer in an organic electroluminescence display.

Detailed ways

Halobenzene, phenylboronic acid, pyridineboronic acid, biphenylboronic acid, naphthaleneboronic acid and 2,7-dibromo-9,9-dimethylfluorene, 2,7-dibromo-9,9 used in the present invention -Basic chemical raw materials such as diphenylfluorene can be purchased in the domestic chemical product market, and various arylphenylboronic acids can be synthesized by common organic methods.

Example

The compound preparation process in the present invention is mainly divided into three steps: (1) usually, phenylboronic acid, pyridineboronic acid, naphthaleneboronic acid or biphenylboronic acid and halogen (2) convert the halide obtained in 1 into arylphenylboronic acid (Organic Syntheses2004, Vol.10, p.80; Vol.79, p.176 (2002 ).).); (3) The boronic acid obtained in 2 is coupled with 2,7-dibromo-9,9-disubstituent fluorene to obtain the target molecule. The above steps are described in detail as follows:

The synthesis of embodiment 1 compound 1-1

(1) the first step

28.3g m-bromoiodobenzene, 12.3g 2-pyridine boronic acid and 0.50g Pd(PPh ₃ ) ₄ were dissolved in 300mL toluene, 22.0g potassium carbonate was dissolved in 100mL water and added to the above reaction solution, then 200mL ethanol was added, and the reaction solution It was yellow, and after reacting at 50°C for 1.5 h, 3.00 g of 2-pyridineboronic acid was added, and the reaction progress was monitored by TLC. After about 0.5 h, the reaction was completed. The organic layer was washed three times with water, dried over anhydrous Na ₂ SO ₄ , spin-dried, and then recrystallized with petroleum ether to obtain 17.40 g of off-white solid. MS (m/e): 234, 74.3% yield.

(2) The second step

Dissolve 23.4g of m-bromo-2-pyridinebenzene and 24.6g of triisopropyl borate in 200mL of dry tetrahydrofuran, drop the temperature to -50°C and add 50mL of butyllithium (2.5M) dropwise, and control the temperature from -40°C to -50°C between ℃. After the dropwise addition, continue to react for 20 minutes between -40°C and -50°C, remove the cooling bath, and naturally raise the temperature to -20°C, slowly add a solution made of 20ml of concentrated hydrochloric acid and 80ml of water for hydrolysis, and then naturally rise to At room temperature, the liquid was separated, and the pH of the aqueous layer was adjusted to neutral with 10% sodium carbonate solution, and a large amount of white solid was precipitated. After suction filtration and drying, 15.3 g of the product was obtained, MS (m/e): 199, and the yield was 76.8%.

(3) The third step

7.04g, 2,7-dibromo-9,9-dimethylfluorene and 12.0g 3-(2-pyridine) phenylboronic acid are dissolved in the mixed solution of 400mL xylene and 300mL ethanol, add 13.8g potassium carbonate and 0.5 g Pd(PPh ₃ ) ₄ , after refluxing for 2 hours, add 2.00 g of 3-(2-pyridine)phenylboronic acid. TLC detected that the reaction was complete, and a large amount of solids were precipitated after cooling and standing, which were washed three times with water. Boil twice more in THF. Finally, 5.10 g of white powder was obtained, namely compound 1-1. MS (m/e): 500, elemental analysis (C ₃₇ H ₂₈ N ₂ ): theoretical value C: 88.77%, H: 5.64%, N: 5.60%; found value C: 88.80%, H: 5.72%, N : 5.48%. Yield 51.0%.

The preparation routes of the last two steps of all target molecules are the same as the preparation of compound 1-1 in Example 1, the only difference lies in the connection position of phenyl and pyridyl and the halogenation position in the first step, which can be selected according to the specific target molecule Different reaction substrates are now specifically described as follows:

The synthesis of embodiment 2 compound 1-2

Using m-bromoiodobenzene and 3-pyridineboronic acid as raw materials, compound 1-2 was obtained through the same three-step reaction as in Example 1. Product MS (m/e): 500, elemental analysis (C ₃₇ H ₂₈ N ₂ ): theoretical value C: 88.77%, H: 5.64%, N: 5.60%; found value C: 88.60%, H: 5.72%, N: 5.68%. Yield 26.3%.

The synthesis of embodiment 3 compound 1-3

Using m-bromoiodobenzene and 4-pyridineboronic acid as raw materials, compound 1-3 was obtained through the same three-step reaction as in Example 1. Product MS (m/e): 500, elemental analysis (C ₃₇ H ₂₈ N ₂ ): theoretical value C: 88.77%, H: 5.64%, N: 5.60%; found value C: 88.64%, H: 5.75%, N: 5.61%. The yield was 29.7%.

The synthesis of embodiment 4 compound 1-4

Using m-bromoiodobenzene and phenylboronic acid as raw materials, compound 1-4 was obtained through the same three-step reaction as in Example 1. Product MS (m/e): 498, elemental analysis (C ₃₉ H ₃₀ ): theoretical value C: 93.94%, H: 6.06%; found value C: 93.78%, H: 6.22%. Yield 32.5%.

The synthesis of embodiment 5 compound 1-5

Using m-bromoiodobenzene and 3-biphenylboronic acid as raw materials, compound 1-5 was obtained through the same three-step reaction as in Example 1. Product MS (m/e): 650, elemental analysis (C ₅₁ H ₃₈ ): theoretical value C: 94.12%, H: 5.88%; found value C: 94.01%, H: 5.99%. Yield 38.2%.

The synthesis of embodiment 6 compound 1-6

Using m-bromoiodobenzene and 4-biphenylboronic acid as raw materials, compound 1-6 was obtained through the same three-step reaction as in Example 1. Product MS (m/e): 650, elemental analysis (C ₅₁ H ₃₈ ): theoretical value C: 94.12%, H: 5.88%; found value C: 94.31%, H: 5.69%. Yield 41.0%.

The synthesis of embodiment 7 compound 1-7

Using m-bromoiodobenzene and 1-naphthylboronic acid as raw materials, compound 1-7 was obtained through the same three-step reaction as in Example 1. Product MS (m/e): 598, elemental analysis (C ₄₇ H ₃₄ ): theoretical value C: 94.28%, H: 5.72%; found value C: 94.12%, H: 5.88%. Yield 37.4%.

The synthesis of embodiment 8 compound 1-8

Using m-bromoiodobenzene and 2-naphthylboronic acid as raw materials, compound 1-8 was obtained through the same three-step reaction as in Example 1. Product MS (m/e): 598, elemental analysis (C ₄₇ H ₃₄ ): theoretical value C: 94.28%, H: 5.72%; found value C: 94.37%, H: 5.63%. Yield 40.1%.

The synthesis of embodiment 9 compound 1-9

Using p-bromoiodobenzene and 2-pyridineboronic acid as raw materials, compound 1-9 was obtained through the same three-step reaction as in Example 1. Product MS (m/e): 500, elemental analysis (C ₃₇ H ₂₈ N ₂ ): theoretical value C: 88.77%, H: 5.64%, N: 5.60%; found value C: 88.62%, H: 5.82%, N: 5.56%. Yield 36.3%.

The synthesis of embodiment 10 compound 1-10

Using p-bromoiodobenzene and 3-pyridineboronic acid as raw materials, compound 1-10 was obtained through the same three-step reaction as in Example 1. Product MS (m/e): 500, elemental analysis (C ₃₇ H ₂₈ N ₂ ): theoretical value C: 88.77%, H: 5.64%, N: 5.60%; found value C: 88.53%, H: 5.87%, N: 5.60%. Yield 35.8%.

The synthesis of embodiment 11 compound 1-11

Using p-bromoiodobenzene and 4-pyridineboronic acid as raw materials, compound 1-11 was obtained through the same three-step reaction as in Example 1. Product MS (m/e): 500, elemental analysis (C ₃₇ H ₂₈ N ₂ ): theoretical value C: 88.77%, H: 5.64%, N: 5.60%; found value C: 88.62%, H: 5.85%, N: 5.53%. Yield 38.2%.

The synthesis of embodiment 12 compound 1-12

Using p-bromoiodobenzene and phenylboronic acid as raw materials, compound 1-12 was obtained through the same three-step reaction as in Example 1. Product MS (m/e): 498, elemental analysis (C ₃₉ H ₃₀ ): theoretical value C: 93.94%, H: 6.06%,; found value C: 93.72%, H: 6.28%. Yield 39.5%.

The synthesis of embodiment 13 compound 1-13

Using p-bromoiodobenzene and 3-biphenylboronic acid as raw materials, compound 1-13 was obtained through the same three-step reaction as in Example 1. Product MS (m/e): 650, elemental analysis (C ₅₁ H ₃₈ ): theoretical value C: 94.12%, H: 5.88%,; found value C: 94.17%, H: 5.83%. Yield 34.9%.

The synthesis of embodiment 14 compound 1-14

Using p-bromoiodobenzene and 4-biphenylboronic acid as raw materials, compound 1-14 was obtained through the same three-step reaction as in Example 1. Product MS (m/e): 650, elemental analysis (C ₅₁ H ₃₈ ): theoretical value C: 94.12%, H: 5.88%; found value C: 94.21%, H: 5.79%. Yield 40.6%.

The synthesis of embodiment 15 compound 1-15

Using p-bromoiodobenzene and 1-naphthylboronic acid as raw materials, compound 1-15 was obtained through the same three-step reaction as in Example 1. Product MS (m/e): 598, elemental analysis (C ₄₇ H ₃₄ ): theoretical value C: 94.28%, H: 5.72%; found value C: 94.11%, H: 5.89%. Yield 38.5%.

The synthesis of embodiment 16 compound 1-16

Using p-bromoiodobenzene and 2-naphthylboronic acid as raw materials, compound 1-16 was obtained through the same three-step reaction as in Example 1. Product MS (m/e): 598, elemental analysis (C ₄₇ H ₃₄ ): theoretical value C: 94.28%, H: 5.72%; found value C: 94.31%, H: 5.69%. Yield 41.2%.

Examples of compounds 2-1 to 2-16 The first two steps of the reaction are the same as in Example 1, and the third step selects the reaction substrate as 2,7-dibromo-9,9-diphenylfluorene, which is now specifically described as follows:

The synthesis of embodiment 17 compound 2-1

Using m-bromoiodobenzene and 2-pyridineboronic acid as raw materials, compound 2-1 was obtained through the same three-step reaction as in Example 1. Product MS (m/e): 624, elemental analysis (C ₄₇ H ₃₂ N ₂ ): theoretical value C: 90.35%, H: 5.16%, N: 4.48%; found value C: 90.42%, H: 5.12%, N: 4.46%. The yield was 29.7%.

The synthesis of embodiment 18 compound 2-2

Using m-bromoiodobenzene and 3-pyridineboronic acid as raw materials, compound 2-2 was obtained through the same three-step reaction as in Example 1. Product MS (m/e): 624, elemental analysis (C ₄₇ H ₃₂ N ₂ ): theoretical value C: 90.35%, H: 5.16%, N: 4.48%; found value C: 90.46%, H: 5.10%, N: 4.44%. Yield 32.3%.

The synthesis of embodiment 19 compound 2-3

Using m-bromoiodobenzene and 4-pyridineboronic acid as raw materials, compound 2-3 was obtained through the same three-step reaction as in Example 1. Product MS (m/e): 624, elemental analysis (C ₄₇ H ₃₂ N ₂ ): theoretical value C: 90.35%, H: 5.16%, N: 4.48%; found value C: 90.31%, H: 5.12%, N: 4.57%. The yield was 34.9%.

The synthesis of embodiment 20 compound 2-4

Using m-bromoiodobenzene and phenylboronic acid as raw materials, compound 2-4 was obtained through the same three-step reaction as in Example 1. Product MS (m/e): 622, elemental analysis (C ₄₉ H ₃₄ ): theoretical value C: 94.50%, H: 5.50%; found value C: 94.57%, H: 5.43%. Yield 34.5%.

The synthesis of embodiment 21 compound 2-5

Using m-bromoiodobenzene and 3-biphenylboronic acid as raw materials, compound 2-5 was obtained through the same three-step reaction as in Example 1. Product MS (m/e): 774, elemental analysis (C ₆₁ H ₄₂ ): theoretical value C: 94.54%, H: 5.46%,; found value C: 94.67%, H: 5.33%. Yield 36.2%.

The synthesis of embodiment 22 compound 2-6

Using m-bromoiodobenzene and 4-biphenylboronic acid as raw materials, compound 2-6 was obtained through the same three-step reaction as in Example 1. Product MS (m/e): 774, elemental analysis (C ₆₁ H ₄₂ ): theoretical value C: 94.54%, H: 5.46%, found value C: 94.43%, H: 5.57%. Yield 34.7%.

The synthesis of embodiment 23 compound 2-7

Using m-bromoiodobenzene and 1-naphthylboronic acid as raw materials, compound 2-7 was obtained through the same three-step reaction as in Example 1. Product MS (m/e): 722, elemental analysis (C ₅₇ H ₃₈ ): theoretical value C: 94.70%, H: 5.30%; found value C: 94.85%, H: 5.15%. Yield 38.4%.

The synthesis of embodiment 24 compound 2-8

Using m-bromoiodobenzene and 2-naphthylboronic acid as raw materials, compound 2-8 was obtained through the same three-step reaction as in Example 1. Product MS (m/e): 722, elemental analysis (C ₅₇ H ₃₈ ): theoretical value C: 94.70%, H: 5.30%; found value C: 94.79%, H: 5.21%. Yield 41.6%.

Synthesis of Example 25 Compound 2-9

Using p-bromoiodobenzene and 2-pyridineboronic acid as raw materials, compound 2-9 was obtained through the same three-step reaction as in Example 1. Product MS (m/e): 624, elemental analysis (C ₄₇ H ₃₂ N ₂ ): theoretical value C: 90.35%, H: 5.16%, N: 4.48%; found value C: 90.27%, H: 5.22%, N: 4.51%. Yield 37.8%.

Synthesis of Example 26 Compound 2-10

Using p-bromoiodobenzene and 3-pyridineboronic acid as raw materials, compound 2-10 was obtained through the same three-step reaction as in Example 1. Product MS (m/e): 624, elemental analysis (C ₄₇ H ₃₂ N ₂ ): theoretical value C: 90.35%, H: 5.16%, N: 4.48%; found value C: 90.27%, H: 5.08%, N: 4.65%. Yield 36.7%.

Synthesis of Example 27 Compound 2-11

Using p-bromoiodobenzene and 4-pyridineboronic acid as raw materials, compound 2-11 was obtained through the same three-step reaction as in Example 1. Product MS (m/e): 624, elemental analysis (C ₄₇ H ₃₂ N ₂ ): theoretical value C: 90.35%, H: 5.16%, N: 4.48%; found value C: 90.48%, H: 5.13%, N: 4.39%. Yield 38.1%.

Synthesis of Example 28 Compound 2-12

Using p-bromoiodobenzene and phenylboronic acid as raw materials, compound 2-12 was obtained through the same three-step reaction as in Example 1. Product MS (m/e): 622, elemental analysis (C ₄₉ H ₃₄ ): theoretical value C: 94.50%, H: 5.50%; found value C: 94.62%, H: 5.38%. Yield 39.7%.

Synthesis of Example 29 Compound 2-13

Using p-bromoiodobenzene and 3-biphenylboronic acid as raw materials, compound 2-13 was obtained through the same three-step reaction as in Example 1. Product MS (m/e): 774, elemental analysis (C ₆₁ H ₄₂ ): theoretical value C: 94.54%, H: 5.46%,; found value C: 94.61%, H: 5.39%. Yield 37.2%.

Synthesis of Example 30 Compound 2-14

Using p-bromoiodobenzene and 4-biphenylboronic acid as raw materials, compound 2-14 was obtained through the same three-step reaction as in Example 1. Product MS (m/e): 774, elemental analysis (C ₆₁ H ₄₂ ): theoretical value C: 94.54%, H: 5.46%,; found value C: 94.48%, H: 5.52%. Yield 40.3%.

Synthesis of Example 31 Compound 2-15

Using p-bromoiodobenzene and 1-naphthylboronic acid as raw materials, compound 2-15 was obtained through the same three-step reaction as in Example 1. Product MS (m/e): 722, elemental analysis (C ₅₇ H _38x ): theoretical value C: 94.70%, H: 5.30%; found value C: 94.81%, H: 5.19%. Yield 38.1%.

Synthesis of Example 32 Compound 2-16

Using p-bromoiodobenzene and 2-naphthylboronic acid as raw materials, compound 2-16 was obtained through the same three-step reaction as in Example 1. Product MS (m/e): 722, elemental analysis (C ₅₇ H ₃₈ ): theoretical value C: 94.70%, H: 5.30%; found value C: 94.75%, H: 5.25%. Yield 40.7%.

The first two-step reactions of the examples of compounds 3-1 to 3-16 are the same as in Example 1, and the third-step reaction substrate is 2,7-dibromo-9,9-di-p-tolylfluorene, which are now specifically described as follows

Synthesis of Example 33 Compound 3-1

Using m-bromoiodobenzene and 2-pyridineboronic acid as raw materials, compound 3-1 was obtained through the same three-step reaction as in Example 1. Product MS (m/e): 652, elemental analysis (C ₄₉ H ₃₆ N ₂ ): theoretical value C: 90.15%, H: 5.56%, N: 4.29%; found value C: 90.10%, H: 5.42%, N: 4.48%. Yield 35.3%.

Synthesis of Example 34 Compound 3-2

Using m-bromoiodobenzene and 3-pyridineboronic acid as raw materials, compound 3-2 was obtained through the same three-step reaction as in Example 1. Product MS (m/e): 652, elemental analysis (C ₄₉ H ₃₆ N ₂ ): theoretical value C: 90.15%, H: 5.56%, N: 4.29%; found value C: 90.04%, H: 5.58%, N: 4.38%. Yield 34.7%.

Synthesis of Example 35 Compound 3-3

Using m-bromoiodobenzene and 4-pyridineboronic acid as raw materials, compound 3-3 was obtained through the same three-step reaction as in Example 1. Product MS (m/e): 652, elemental analysis (C ₄₉ H ₃₆ N ₂ ): theoretical value C: 90.15%, H: 5.56%, N: 4.29%; found value C: 90.23%, H: 5.40%, N: 4.37%. Yield 37.2%.

Synthesis of Example 36 Compound 3-4

Using m-bromoiodobenzene and phenylboronic acid as raw materials, compound 3-4 was obtained through the same three-step reaction as in Example 1. Product MS (m/e): 650, elemental analysis (C ₅₁ H ₃₈ ): theoretical value C: 94.12%, H: 5.88%; found value C: 94.03%, H: 5.97%. Yield 36.5%.

Synthesis of Example 37 Compound 3-5

Using m-bromoiodobenzene and 3-biphenylboronic acid as raw materials, compound 3-5 was obtained through the same three-step reaction as in Example 1. Product MS (m/e): 802, elemental analysis (C ₆₃ H ₄₆ ): theoretical value C: 94.23%, H: 5.77%,; found value C: 94.10%, H: 5.90%. Yield 38.6%.

Synthesis of Example 38 Compound 3-6

Using m-bromoiodobenzene and 4-biphenylboronic acid as raw materials, compound 3-6 was obtained through the same three-step reaction as in Example 1. Product MS (m/e): 802, elemental analysis (C ₆₃ H ₄₆ ): theoretical value C: 94.23%, H: 5.77%,; found value C: 94.10%, H: 5.90%. Yield 38.3%.

Synthesis of Example 39 Compound 3-7

Using m-bromoiodobenzene and 1-naphthylboronic acid as raw materials, compound 3-7 was obtained through the same three-step reaction as in Example 1. Product MS (m/e): 750, elemental analysis (C ₅₉ H ₄₂ ): theoretical value C: 94.36%, H: 5.64%; found value C: 94.45%, H: 5.55%. Yield 38.3%.

The synthesis of embodiment 40 compound 3-8

Using m-bromoiodobenzene and 2-naphthylboronic acid as raw materials, compound 3-8 was obtained through the same three-step reaction as in Example 1. Product MS (m/e): 750, elemental analysis (C ₅₉ H ₄₂ ): theoretical value C: 94.36%, H: 5.64%; found value C: 94.29%, H: 5.71%. Yield 40.6%.

Synthesis of Example 41 Compound 3-9

Using p-bromoiodobenzene and 2-pyridineboronic acid as raw materials, compound 3-9 was obtained through the same three-step reaction as in Example 1. Product MS (m/e): 652, elemental analysis (C ₄₉ H ₃₆ N ₂ ): theoretical value C: 90.15%, H: 5.56%, N: 4.29%; found value C: 90.22%, H: 5.45%, N: 4.33%. Yield 40.6%.

Synthesis of Example 42 Compound 3-10

Using p-bromoiodobenzene and 3-pyridineboronic acid as raw materials, compound 3-10 was obtained through the same three-step reaction as in Example 1. Product MS (m/e): 652, elemental analysis (C ₄₉ H ₃₆ N ₂ ): theoretical value C: 90.15%, H: 5..6%, N: 4.29%; found value C: 90.06%, H: 5.52%, N: 4.42%. Yield 37.8%.

Synthesis of Example 43 Compound 3-11

Using p-bromoiodobenzene and 4-pyridineboronic acid as raw materials, compound 3-11 was obtained through the same three-step reaction as in Example 1. Product MS (m/e): 652, elemental analysis (C ₄₉ H ₃₆ N ₂ ): theoretical value C: 90.15%, H: 5.56%, N: 4.29%; found value C: 90.12%, H: 5.42%, N: 4.46%. Yield 39.2%.

Synthesis of Example 44 Compound 3-12

Using p-bromoiodobenzene and phenylboronic acid as raw materials, compound 3-12 was obtained through the same three-step reaction as in Example 1. Compound MS (m/e): 650, elemental analysis (C ₅₁ H ₃₈ ): theoretical value C: 94.12%, H: 5.88%; found value C: 94.21%, H: 5.79%. Yield 39.2%.

Synthesis of Example 45 Compound 3-13

Using p-bromoiodobenzene and 3-biphenylboronic acid as raw materials, compound 3-13 was obtained through the same three-step reaction as in Example 1. Product MS (m/e): 802, elemental analysis (C ₆₃ H ₄₆ ): theoretical value C: 94.23%, H: 5.77%,; found value C: 94.14%, H: 5.86%. Yield 37.9%.

Synthesis of Example 46 Compound 3-14

Using p-bromoiodobenzene and 4-biphenylboronic acid as raw materials, compound 3-14 was obtained through the same three-step reaction as in Example 1. Product MS (m/e): 802, elemental analysis (C ₆₃ H ₄₆ ): theoretical value C: 94.23%, H: 5.77%,; found value C: 94.30%, H: 5.70%. Yield 40.6%.

Synthesis of Example 47 Compound 3-15

Using p-bromoiodobenzene and 1-naphthylboronic acid as raw materials, compound 3-15 was obtained through the same three-step reaction as in Example 1. Product MS (m/e): 750, elemental analysis (C ₅₉ H ₄₂ ): theoretical value C: 94.36%, H: 5.64%; found value C: 94.41%, H: 5.59%. Yield 38.5%.

Synthesis of Example 48 Compound 3-16

Using p-bromoiodobenzene and 2-naphthylboronic acid as raw materials, compound 3-16 was obtained through the same three-step reaction as in Example 1. Product MS (m/e): 750, elemental analysis (C ₅₉ H ₄₂ ): theoretical value C: 94.36%, H: 5.64%; found value C: 94.31%, H: 5.69%. Yield 40.7%.

Below are the application examples of the compounds of the present invention:

Example 49: Preparation and Results of Electroluminescent Devices

Preferred embodiment of the device:

(1) Device design

For the convenience of comparing the transport properties of these electron transport materials, the present invention has designed - simple electroluminescent device (substrate/anode/hole transport layer (HTL)/organic light-emitting layer (EL)/electron transport layer (ETL)/cathode) , using only compound 1-1, 2-1, 2-8 or 3-1 as an example of electron transport material, high-efficiency electron transport material Alq ₃ as a comparative material, and EM1 as an example of a light emitting material (EM1 is a host material, not a light emitting material, The purpose is not to pursue high efficiency, but to verify the practical possibility of these materials). The structures of Alq ₃ and EM1 are:

The substrate can be a substrate in a conventional organic light emitting device, such as glass or plastic. In the fabrication of the device of the present invention, a glass substrate is selected, and ITO is used as the anode material.

Various triarylamine materials can be used for the hole transport layer. The hole-transporting material selected in the fabrication of the device of the present invention is NPB.

The cathode can adopt metal and its mixture structure, such as Mg:Ag, Ca:Ag, etc., or an electron injection layer/metal layer structure, such as LiF/Al, Li ₂ O and other common cathode structures. The electron injection material selected in the device fabrication of the present invention is LiF, and the cathode material is Al.

(2) Device production

The glass plate coated with the ITO transparent conductive layer is ultrasonically treated in a commercial cleaning agent, rinsed in deionized water, ultrasonically degreased in acetone:ethanol mixed solvent, baked in a clean environment until the water is completely removed, and then cleaned with ultraviolet light. Light and ozone cleaning, and bombardment of the surface with a beam of low-energy cations;

Place the above-mentioned glass substrate with an anode in a vacuum chamber, evacuate to 1× ^10-5 Pa～9× ^10-3 Pa, vacuum-deposit NPB on the above-mentioned anode layer film as a hole transport layer, evaporate The rate is 0.1nm/s, and the evaporation film thickness is 50nm;

On the hole transport layer, EM1 was vacuum evaporated as the light-emitting layer of the device, the evaporation rate was 0.1nm/s, and the total film thickness was 30nm;

A layer of compound 1-1, 2-1, 2-8, 3-1 or Alq ₃ was vacuum evaporated on the light-emitting layer as the electron transport layer of the device. The evaporation rate was 0.1nm/s, and the total film was evaporated. 50nm thick;

An Al layer was vacuum-evaporated on the electron transport layer (ETL) as the cathode of the device with a thickness of 150 nm.

The device performance is shown in the table below (device structure: ITO/NPB(40nm)/EM1(30nm)/ETL material(20nm)/LiF(0.5nm)/Al(150nm))

The above results show that the novel organic material of the present invention can be preferably used as an electron transport layer in an organic electroluminescent device.

Although the present invention has been described in conjunction with the embodiments, the present invention is not limited to the above-mentioned embodiments. It should be understood that under the guidance of the inventive concept, those skilled in the art can carry out various modifications and improvements, and the appended claims summarize scope of the invention.

Claims (4)

1. A kind of organic compound, its general structural formula is as shown in formula I below:

Wherein, Ar is a pyridyl group, R is an alkyl or aryl group; When R is an alkyl group, one selected from methyl, ethyl, propyl, isopropyl, butyl, isobutyl, n-pentyl, n-hexyl; When R is an aryl group, it is selected from one of phenyl, biphenyl, and naphthyl. 2. The compound according to claim 1, the structural formula is selected from the following formulas:

3. The compound according to claim 1 is used as an electron transport layer material in an organic electroluminescent device. 4. An organic electroluminescent device, comprising a pair of electrodes and an organic luminescent medium disposed between the pair of electrodes, the organic luminescent medium at least comprising one compound selected from claim 1.