CN1931803B - A kind of organic electroluminescent material and its application - Google Patents

Abstract

The present invention is one new type of organic electroluminescent material compound and the organic electroluminescent device with the compound. The compound has the structural generation formula as shown. The organic electroluminescent material has very high film fluorescence quantum yield and film luminescence intensity, and excellent stability and filming performance. The organic electroluminescent material is preferably used as non-doped luminescent material, and may be used as dye doped into other main luminescent material, hole transporting material, electron barrier material, etc.

Description

A kind of organic electroluminescent material and its application

technical field

The invention relates to a small molecule organic electroluminescent material and its application in organic electroluminescent devices, belonging to the technical field of organic electroluminescent display.

Background technique

Organic electroluminescent devices (hereinafter referred to as organic EL) are widely used in various fields due to their ultra-thin, fully cured, self-luminous, fast response, good temperature characteristics, and flexible display.

Research on organic EL began in the 1960s. In 1963, Pope et al. (J.Chem.Phys.1963, 38:2042～2043) studied the blue electroluminescence of anthracene single crystal (10～20μm), because the anthracene single crystal light-emitting layer was thick and the electrodes used Due to the constraints of materials (silver colloid and sodium chloride solution), the luminous starting voltage of the device is as high as 400V, and the efficiency and brightness are low. However, the discovery opens up a new field of light-emitting technology. In the following two decades, the research on organic EL has progressed slowly. It was not until 1987 that C.W.Tang et al. (Appl. Phys. Lett. 1987, 51: 913-915) of Kodak Corporation of the United States made a milestone breakthrough. They adopted a double-layer device with 8-hydroxyquinoline aluminum (Alq3) as the light-emitting layer, aromatic diamine as the hole transport layer, ITO as the anode, and Mg:Ag (10:1) alloy as the cathode. High quantum efficiency (1%) and luminous efficiency (1.5lm/W): devices with high brightness (>1000cd/m2) and lower driving voltage (≤10V). This progress has reawakened the application of organic EL in full-color flat panel displays The research of materials and devices has rapidly become a research hot spot. In 1988, Adchi et al. [J.Appl.Phys.1988,27(2):L269～L271] introduced a multi-layer sandwich structure, which greatly expanded the organic EL material selection range.

After 20 years of development, organic EL materials have fully realized red, blue, and green luminescence, and the application field has also expanded from small molecules to polymers and metal complexes. Theoretically, organic electroluminescent display technology has matured, and some products have entered the market, but there are still many problems to be solved in the process of commercialization. Especially for various organic materials used to make devices, many problems have not been solved, such as carrier injection, transport performance, material electroluminescence performance, service life, color purity, matching between materials and electrodes, etc. . At the same time, new materials with better performance are constantly being discovered and used, and device manufacturing technology and device performance are constantly improving.

Common small molecule blue light materials include perylenes, substituted anthracenes, fluorenes, stilbene-aryls, etc. The problem with perylene blue light materials is that their energy levels do not match Alq ₃ , and TBP(2,5 , 8,11-tetra-tert-butylperylene) will be improved when doped into BAlq. Kodak, TDK, Visionox and other companies have reported on the replacement of anthracene materials. The color purity of such materials is average, and they are easy to crystallize and difficult to form amorphous films. The thermal stability and fluorescence quantum efficiency of fluorene materials are good, but the color purity of their devices is average, and their synthesis is difficult. The stilbene-aryl (DSA) structure proposed by Japan's Idemitsu Kosan has great advantages, and its brightness, efficiency, and lifespan are all improved, and the corresponding mechanism of action is still being explored. In addition, small molecule blue light materials also have different structures such as organosilicon and organic boron, which makes the range of blue light materials available for selection wider and wider.

The basic structure of an organic EL device includes anode/hole injection and transport layer/organic light-emitting layer/electron injection layer/cathode. Attenuation is quite fast, so it is still difficult to apply to actual production.

Contents of the invention

The technical problem to be solved by the invention is to propose a new type of organic electroluminescence material, especially a blue light material, and a light emitting device using the material.

The present invention proposes a compound represented by the following general formula (1):

Wherein X, Y must be in the ortho or para position of the biphenyl bond, X', Y' are in the meta position of the biphenyl bond, m, n represent integers of 1-3, p, q represent integers of 0-2.

In the above structural formula (1), X and Y are each independently selected from the following general formula (2) or (3):

In the above structural formula (1), X' and Y' are each independently selected from the general formula (2) or (3), or each independently represents a hydrogen atom, or each independently represents an aromatic group containing 6-30 carbon atoms, containing 10 -A fused aromatic group of 30 carbon atoms, an aromatic heterocyclic group of 5-30 carbon atoms, an alkyl group of 1 to 10 carbon atoms, an alkoxy group of 1 to 10 carbon atoms, and an alkoxy group of 6 to 30 carbon atoms Aralkyl groups of 30 carbon atoms, aryloxy groups of 6 to 30 carbon atoms;

Each of the substituents R ₁ , R ₂ , R ₃ , R ₄ and R ₅ in the general formulas (2) and (3) independently represents a hydrogen atom, an aromatic group containing 6-50 carbon atoms, containing 10-50 A fused aromatic group containing 5-50 carbon atoms, an aromatic heterocyclic group containing 5-50 carbon atoms, an alkylamino group containing 2-50 carbon atoms, an aralkyl group containing 6-50 carbon atoms, containing 6-50 carbon atoms An aryloxy group having carbon atoms, an arylamino group having 6 to 50 carbon atoms, and the like.

Among the substituents in the above general formulas (2) and (3), when R ₁ to R ₅ are aromatic groups containing 6-50 carbon atoms, they can be the following groups: phenyl, o-tolyl, m-toluene Base, p-tolyl, 2-biphenyl, 3-biphenyl, 4-biphenyl, p-methylbiphenyl, p-terphenyl, m-terphenyl, p-tert-butylphenyl, 2 , 4-difluorophenyl, p-(1-naphthyl)phenyl, p-(2-naphthyl)phenyl, distyryl, tristyryl, methoxyphenyl, phenoxybenzene Base etc.

When R ₁ to R ₅ are condensed aromatic groups containing 10-50 carbon atoms, they can be the following groups: 1-naphthyl, 2-naphthyl, 1-anthracenyl, 2-anthracenyl, 9-anthracenyl , 1-phenanthrenyl, 2-phenanthrenyl, 3-phenanthrenyl, 4-phenanthrenyl, 9-phenanthrenyl, 1-pyrenyl, 2-pyrenyl, 4-pyrenyl, 1-naphthacene, 2- Naphthacene, 9-naphthalenyl, fluorenyl, benzo(9,10)phenanthrenyl, fluoranthenyl, chrysene, 3-methyl-2-naphthyl, 4-methyl-1-naphthalene Base, 4-methyl-1-anthracenyl, etc.

When R ₁ to R ₅ are aromatic heterocyclic groups containing 5-50 carbon atoms, they can be the following groups: pyrrolyl, pyridyl, indolyl, isoindolyl, furyl, benzofuryl, iso Benzofuryl, quinolinyl, isoquinolyl, quinoxalinyl, carbazolyl, phenanthridinyl, acridinyl, phenanthrolinyl, o-phenanthrolinyl, phenazinyl, phenothiazinyl , phenoxazinyl, oxazolyl, oxadiazolyl, furazanyl, thienyl, benzothienyl, benzothiazolyl, methylpyrrolyl, tert-butylpyrrolyl, methylindolyl, tert Butylindyl, Julolidinyl, 1,1,7,7-Tetramethyljulolidinyl, etc.

When _R1 to _R5 are alkylamino groups containing 2 to 50 carbon atoms, they can be the following groups: N, N-dimethylamino, N, N-diethylamino, N-methyl-N-ethyl Amino, N,N-dipropylamino, N,N-dibutylamino, N,N-dipentylamino, etc.

When R ₁ to R ₅ are aralkyl groups containing 6 to 50 carbon atoms, they can be the following groups: benzyl, 1-phenylethyl, 2-phenylethyl, 1-phenylisopropyl , 2-phenylisopropyl, phenyl-tert-butyl, α-naphthylmethyl, 1-α-naphthylethyl, 2-α-naphthylethyl, 1-α-naphthylisopropyl, 2-α-naphthylisopropyl, β-naphthylmethyl, 1-β-naphthylethyl, 2-β-naphthylethyl, 1-β-naphthylisopropyl, 2-β-naphthalene Isopropyl, 1-pyrrolylmethyl, 2-(1-pyrrolyl)ethyl, p-methylbenzyl, m-methylbenzyl, o-methylbenzyl, p-fluoro Benzyl, etc.

When R ₁ to R ₅ are aryloxy groups containing 6 to 50 carbon atoms, they can be the following groups: phenoxy, 1-naphthyloxy, 2-naphthyloxy, 1-anthracenyloxy, 2-Anthracenyloxy, 9-Anthracenyloxy, 1-phenanthrenyloxy, 2-phenanthrenyloxy, 3-phenanthrenyloxy, 4-phenanthrenyloxy, 9-phenanthrenyloxy, 1 -pyrenyloxy, 2-pyrenyloxy, 4-pyrenyloxy, 2-biphenyloxy, 3-biphenyloxy, 4-biphenyloxy, o-tolyloxy, m-tolyloxy, p-tolyloxy, p-tert-butylphenyloxy, etc.

When R ₁ to R ₅ are arylamino groups containing 6 to 50 carbon atoms, they can be the following groups: N, N-diphenylamino, N-phenyl-N-tolylamino, N-phenyl-N- Methoxyphenylamino, N,N-xylylamino, N,N-diisopropylphenylamino, N,N-di-tert-butylphenylamino, N-phenyl-N-naphthylamino , N-phenyl-N-biphenylamino, N,N-biphenylamino, N,N-dinaphthylamino, N-naphthyl-N-biphenylamino, etc.

An organic electroluminescent device comprising an anode, a cathode and an organic functional layer, wherein at least one layer of the organic functional layer comprises a single or mixed component compound represented by the following general formula (1):

Wherein X and Y are in the ortho or para position of the biphenyl bond, X' and Y' are in the meta position of the biphenyl bond, m and n represent integers of 1-3, and p and q represent integers of 0-2;

The X and Y are each independently selected from the following general formula (2) or (3);

X' and Y' are each independently selected from the general formula (2) or (3), or each independently represents a hydrogen atom, or each independently represents an aromatic group containing 6-30 carbon atoms, or a condensed group containing 10-30 carbon atoms Aryl group, aromatic heterocyclic group containing 5-30 carbon atoms, alkyl group containing 1-10 carbon atoms, alkoxy group containing 1-10 carbon atoms, arane group containing 6-30 carbon atoms group, aryloxy group containing 6 to 30 carbon atoms;

Each substituent R ₁ , R ₂ , R ₃ , R ₄ and R ₅ in the general formula (2) and (3) independently represents a hydrogen atom, an aromatic group containing 6-50 carbon atoms, containing 10-50 Fused aromatic groups of carbon atoms, aromatic heterocyclic groups containing 5-50 carbon atoms, alkylamino groups containing 2-50 carbon atoms, aralkyl groups containing 6-50 carbon atoms, containing 6-50 carbon atoms atom of aryloxy group or arylamino group of 6 to 50 carbon atoms.

In order to more clearly describe the contents of the present invention, the following specifically describe but are not limited to the preferred structures in the compound types involved in the present invention:

When m=1, n=1, p=0, q=0, and X, Y are the same group, preferred concrete compound C1-C28 is as follows:

When m=1, n=1, p=0, q=0, and X, Y are different groups, preferred specific compounds C29-C54 are as follows:

When m=1, n=1, p+q=1, and X and Y are the same group, preferred specific compounds C55-C65 are as follows:

When m=1, n=1, p+q=1, and X, Y are different groups, preferred specific compounds C66-C75 are as follows:

When m=1, n=1, p+q=2, and X, Y are the same group, preferred specific compounds C76-C95 are as follows:

When m=1, n=1, p+q=2, and X and Y are different groups, preferred specific compounds C96-C103 are as follows:

When m+n=3, preferred specific compounds C104-C113 are shown below:

When m+n=4, preferred specific compounds C114-C118 are shown below:

When p+q=3-4, preferred specific compounds C114-C118 are shown below:

Other preferred compounds C119-C124 are shown below:

The material of the present invention uses biphenyl as the matrix, and n-electron or π-electron groups are connected at the ortho or para-position of the biphenyl bond, so that the molecule as a whole forms a large conjugated system, and at the same time, it can also be connected at the meta-position of the biphenyl bond. Related groups enhance this conjugation effect. Such a structural design ensures that this type of material has good luminescent properties due to the suppression of intra-molecular and intermolecular fluorescence quenching, as well as good stability and film-forming properties. .

The organic electroluminescent material of the present invention has very high thin film fluorescence quantum yield and thin film luminous intensity, and the stability and film forming performance of the material are good, and this type of material can be preferentially used as a non-doped luminescent material, and can also be used as a dye Doped with other host materials to emit light, and can also be used as hole transport or electron blocking materials.

The organic electroluminescent device prepared by using the luminescent material of the invention can exhibit superior performances of high purity, high brightness and high efficiency.

Description of drawings

Fig. 1 is the voltage-current density-brightness curve of the device in embodiment eleven;

Fig. 2 is the current density-efficiency curve of the device in embodiment eleven;

Fig. 3 is the emission wavelength curve of the device in the eleventh embodiment.

Detailed ways

The compound expressed by the general formula (1) proposed by the present invention is generally synthesized according to the Suzuki coupling reaction, while using Witting reaction, halogenation reaction, Ullmann reaction, boration reaction and other synthetic intermediates to prepare the target compound.

The synthesis method of the compound expressed by the general formula (1) proposed by the present invention will be realized with reference to the description of the following examples, but is not limited to the following examples.

Synthetic examples of intermediate compounds:

Synthesis of intermediate bromides

Synthetic Example 1 (synthetic 2,5-dibromomethyl bromobenzene)

Weighing 12 grams of p-dimethylbromobenzene, 25.2 grams of NBS, BPO catalytic amount, 60 milliliters of carbon tetrachloride in a 250 milliliter three-necked flask, the mixture is slowly warming up to reflux under stirring, and it can be observed that there is foam generation soon after the reaction begins. Point the board to see that there is no more raw material to react and stop. The reaction time is about 2-3 hours. Suction filtration, collect the filtrate, and separate through column chromatography. The eluent is pure petroleum ether. Collect the last fraction and evaporate the solvent to obtain white Solid 9.25 grams.

The product m/z=342, 344 and 340 obtained by mass spectrometry analysis, the calculated target product molecular weight C8H7Br3=343, the compound was confirmed to be 2,5-dibromomethylbromobenzene (yield: 42%).

Synthesis Example 2 (synthesis of N, N-diphenyl-3-bromo-4-bromomethylaniline)

Referring to the method described in Synthesis Example 1, N,N-diphenyl-3-bromo-4-methylaniline was used as a raw material (see Synthesis Example 5) to obtain 8.30 g of light yellow solid.

Mass spectrometry obtained product m/z=417,415 and 419, calculate target product molecular weight C19H15Br2N=417, compound is confirmed to be N, N-diphenyl-3-bromo-4-bromomethylaniline (yield: 47% ).

Synthetic Example 3 (synthetic 2,4-dibromomethyl bromobenzene)

Referring to the method described in Synthesis Example 1, 2,4-dimethylbromobenzene was used as the raw material to obtain 9.12 g of white solid.

The product m/z=342, 344 and 340 obtained by mass spectrometry analysis, the calculated target product molecular weight C8H7Br3=343, the compound was confirmed to be 2,4-dibromomethylbromobenzene (yield: 40%).

Synthesis of Intermediate Bromotriphenylamine

Synthesis Example 4 (synthesis of N, N-diphenyl-2-bromoaniline)

According to the improved Ullmann reaction synthesis, weigh 3.3 grams of 2-bromoaniline, 8.6 grams of iodobenzene, 7.2 grams of active copper powder, 20 grams of potassium carbonate, an appropriate amount of 18-crown-6 ether, and 80 milliliters of o-dichlorobenzene in a 250 milliliter three-necked bottle , under nitrogen protection, electromagnetic stirring, heating to reflux. Point the board to see that there is no more raw material 2-bromoaniline to stop the reaction. The reaction time is about 4-5 hours. Suction filtration while it is hot, collect the filtrate, and separate through column chromatography. The eluent is petroleum ether: ethyl acetate=10 : 1, the solvent was distilled off to obtain 4.8 g of white solid.

The product m/z=323 and 325 were analyzed by mass spectrometry, and the molecular weight of the target product was calculated as C18H14BrN=324. The compound was confirmed to be N,N-diphenyl-2-bromoaniline (yield: 78%).

Synthesis Example 5 (synthesis of N, N-diphenyl-3-bromo-4-methylaniline)

Referring to the method described in Synthesis Example 4, 3-bromo-4-methylaniline was used as the raw material to obtain 6.25 g of light yellow solid.

Mass spectrometry analysis of the product m/z=337 and 339, the calculated molecular weight of the target product C19H16BrN=338, the compound was confirmed to be N,N-diphenyl-3-bromo-4-methylaniline (yield: 76%).

Synthesis Example 6 (synthesis of N, N-two (4-phenylphenyl)-p-bromoaniline)

Referring to the method described in Synthesis Example 4, 4-bromoaniline and 4-iodobiphenyl were used as raw materials to obtain 5.80 g of light yellow solid.

The product m/z=475 and 477 obtained by mass spectrometry analysis, the calculated target product molecular weight C30H22BrN=476, the compound was confirmed to be N,N-bis(4-phenylphenyl)-p-bromoaniline (yield: 70%).

Synthesis of Intermediate Bromotriphenylethylene

Synthesis Example 7 (synthesis of 1,1-diphenyl-2-(2-bromophenyl)ethene)

Synthesize according to the improved Witting reaction, weigh 3.1 grams of 2-bromomethyl bromobenzene, 2.3 milliliters of trimethyl phosphite in a 100 milliliter single-port bottle, assemble a condenser tube and a drying tube on the single-port bottle, and gradually heat up to reflux under stirring, Keep it for 6-7 hours, and then change to vacuum distillation until there is no smell of trimethyl phosphite, and a viscous liquid is obtained.

Add the above liquid together with 2.2 grams of benzophenone, 1.2 grams of sodium hydride (the content is 50%), and 30 milliliters of dried tetrahydrofuran into a 250 milliliter three-necked flask, and stir at room temperature for 1 hour under the protection of argon. , and then heated to reflux and reacted overnight. Point the plate to judge the reaction progress, lower to room temperature, slowly add 20 ml of anhydrous methanol dropwise, stir for 1-2 hours, then add appropriate amount of deionized water and dichloromethane, and separate the organic phase. After separation by column chromatography, the eluent was petroleum ether: ethyl acetate = 50:1. The desired fractions were collected, concentrated properly, and left to stand to precipitate 2.4 g of a light yellow solid.

The product m/z=334 and 336 were analyzed by mass spectrometry, and the molecular weight of the target product was calculated as C20H15Br=335. The compound was confirmed to be 1,1-diphenyl-2-(2-bromophenyl)ethylene (yield: 60%).

Synthesis Example 8 (synthesis of 1,1-diphenyl-2-(4-bromophenyl)ethylene)

Referring to the method described in Synthesis Example 7, 4-bromomethylbromobenzene was used as the raw material to obtain 2.8 g of light yellow solid.

The product m/z=334 and 336 were analyzed by mass spectrometry, and the molecular weight of the target product was calculated as C20H15Br=335. The compound was confirmed to be 1,1-diphenyl-2-(4-bromophenyl)ethylene (yield: 62%).

Synthetic Example 9 (2-(2,2-diphenylethenyl)-5-diphenylaminobromobenzene)

Referring to the method described in Synthesis Example 7, N,N-diphenyl-3-bromo-4-bromomethylaniline was used as the raw material (see Synthesis Example 2) to obtain 3.7 g of light yellow solid.

The mass spectrometric analysis obtained product m/z=501 and 503, calculated target product molecular weight C32H24BrN=502, compound is confirmed to be 2-(2,2-diphenylvinyl)-5-dianilino bromobenzene (yield: 67 %).

Synthesis Example 10 (synthesis of 2,5-bis(2,2-diphenylethenyl) bromobenzene)

Synthesize according to the improved Witting reaction, weigh 5.0 grams of 2,5-dibromomethyl bromide (see Synthesis Example 1), and 5.2 milliliters of trimethyl phosphite in a 100 milliliter single-necked bottle, which is equipped with a condenser and dried tube, gradually warming up to reflux under stirring, keeping for 6-7 hours, and then changing to vacuum distillation until there is no smell of trimethyl phosphite, and a yellow viscous liquid is obtained.

Add the above liquid together with 5.2 g of benzophenone, 4.0 g of sodium hydride (the content is 50%), and 50 ml of dried tetrahydrofuran into a 250 ml three-necked flask, and stir at room temperature for 1 hour under the protection of argon. , and then heated to reflux and reacted overnight. Point the plate to judge the reaction progress, lower to room temperature, slowly add 30 ml of anhydrous methanol dropwise, stir for 1-2 hours, then add appropriate amount of deionized water and dichloromethane, and separate the organic phase. After separation by column chromatography, the eluent was petroleum ether: ethyl acetate = 50:1. The desired fractions were collected, concentrated properly and left to stand to precipitate 4.28 g of light yellow crystals.

The product m/z=512 and 514 obtained by mass spectrometry analysis, the calculated target product molecular weight C34H25Br=513, the compound was confirmed to be 2,5-bis(2,2-diphenylvinyl)bromobenzene (yield: 57%).

Synthesis Example 11 (synthesis of 2,4-bis(2,2-diphenylethenyl) bromobenzene)

Referring to the method described in Synthesis Example 10, 2,4-dibromomethylbromobenzene was used as the raw material (see Synthesis Example 3) to obtain 5.23 g of light yellow solid.

Mass spectrometric analysis of the product m/z=512 and 514, the calculated molecular weight of the target product C34H25Br=513, the compound was confirmed to be 2,4-bis(2,2-diphenylvinyl)bromobenzene (yield: 53%).

Synthesis of Intermediate Arylboronic Acid

Synthesis Example 12 (Synthesis of 2-(2,2-diphenylvinyl)phenylboronic acid)

Synthesize according to the method of conventional boration, claim to synthesize 2.0 grams of 1,1-diphenyl-2-(2-bromophenyl)ethylene (see Synthesis Example 7), and add 20 milliliters of dried tetrahydrofuran to 250 milliliters In the three-neck flask, under the protection of argon, stir and dissolve into a yellow transparent liquid. The mixture is cooled to below -64°C with liquid nitrogen, and 3ml of 2.5M n-butyllithium is slowly added dropwise (the dropping time exceeds 15min), and the reaction is at - Continue below 64°C for 2 hours, the mixture is a brownish-yellow turbid liquid. Slowly add 2.5 ml of freshly distilled trimethyl borate dropwise at below -64°C. After the dropwise addition, the temperature is naturally raised to room temperature and stirred overnight. The reaction mixture was cooled to below 10°C with an ice bath, 20 ml of 2N hydrochloric acid solution was added dropwise, and after stirring for a long enough time, it was extracted with dichloromethane, the organic phase was collected and evaporated to dryness, washed 1-2 times with petroleum ether, and dried , to obtain 0.98 g of white powder.

The product obtained by mass spectrometry analysis m/z=300, calculated target product molecular weight C20H17BO2=300, the compound was confirmed to be 2-(2,2-diphenylvinyl)phenylboronic acid (yield: 52%)

Synthesis Example 13 (Synthesis of 4-(2,2-diphenylvinyl)phenylboronic acid)

Referring to the method described in Synthesis Example 12, 1,1-diphenyl-2-(4-bromophenyl)ethylene was used as a raw material (see Synthesis Example 8) to obtain 1.0 g of a white solid.

The product obtained by mass spectrometry analysis m/z=300, calculated target product molecular weight C20H17BO2=300, the compound was confirmed to be 2-(2,2-diphenylvinyl)phenylboronic acid (yield: 53%)

Synthesis Example 14 (Synthesis of 2-Dianilinophenylboronic Acid)

Referring to the method described in Synthesis Example 12, using N,N-diphenyl-2-bromoaniline as a raw material (see Synthesis Example 4) to obtain 1.0 g of white solid.

The product obtained by mass spectrometry analysis m/z=289, calculated target product molecular weight C18H16BNO2=289, the compound was confirmed to be 2-dianilinophenylboronic acid (yield: 48%)

Synthesis Example 15 (Synthesis of 2,5-bis(2,2-diphenylvinyl)phenylboronic acid)

Weigh 3.1 grams of 2,5-bis(2,2-diphenylvinyl)bromobenzene (see Synthesis Example 10), and add 20 milliliters of dried tetrahydrofuran into a 250 milliliter three-necked flask together, under argon protection , stirred and dissolved into a yellow transparent liquid, the mixture was cooled to below -64°C with liquid nitrogen, and 3ml of 2.5M n-butyllithium was slowly added dropwise (dropping time exceeded 15min), and the reaction continued for 2 hours below -64°C, the mixture was Brown-yellow cloudy liquid. Slowly add 2.5 ml of freshly distilled trimethyl borate dropwise at below -64°C. After the dropwise addition, the temperature is naturally raised to room temperature and stirred overnight.

The reaction mixture was cooled to below 10°C with an ice bath, 20 ml of 2N hydrochloric acid solution was added dropwise, and after stirring for a long enough time, it was extracted with dichloromethane, the organic phase was collected and evaporated to dryness, washed 1-2 times with petroleum ether, and dried , to obtain 1.43 g of light yellow powder.

The product obtained by mass spectrometry analysis m/z=478, calculated target product molecular weight C34H27BO2=478, the compound was confirmed to be 2,5-bis(2,2-diphenylvinyl)phenylboronic acid (yield: 48%)

Synthesis Example 16 (Synthesis of 2,4-bis(2,2-diphenylvinyl)phenylboronic acid)

Referring to the method described in Synthesis Example 15, 2,4-bis(2,2-diphenylvinyl)bromobenzene (see Synthesis Example 11) was used as the raw material to obtain 1.33 g of light yellow powder.

The product obtained by mass spectrometry analysis m/z=478, calculated target product molecular weight C34H27BO2=478, the compound was confirmed to be 2,4-bis(2,2-diphenylvinyl)phenylboronic acid (yield: 52%)

Synthetic Example 17 (2-(2,2-diphenylvinyl)-5-dianilinophenylboronic acid)

Referring to the method described in Synthesis Example 12, 2-(2,2-diphenylvinyl)-5-dianilinobromobenzene (see Synthesis Example 9) was used as the raw material to obtain 1.67 g of light yellow powder.

Mass spectral analysis obtained product m/z=467, calculate target product molecular weight C32H26BNO2=467, compound is confirmed to be 2-(2,2-diphenylvinyl)-5-dianilinophenylboronic acid (yield: 43% )

Below is the synthesis embodiment of target compound of the present invention:

Embodiment one (synthetic compound (C1))

Under the protection of argon, 0.90 g of 1,1-diphenyl-2-(2-bromophenyl)ethylene (see Synthesis Example 7), 2-(2,2-diphenylethenyl)phenyl 0.91 grams of boric acid (see Synthesis Example 12), 0.04 grams of palladium dichloride, 0.12 grams of triphenylphosphine, 1.4 grams of potassium carbonate, 20 milliliters of deionized water, 20 milliliters of absolute ethanol, and 30 milliliters of toluene were added together to 250 ml three-necked flask, stirred, heated to reflux, and the reaction time was not less than 24 hours. After the reaction, the organic phase was separated and purified by column chromatography to obtain 1.0 g of a yellow solid.

The product obtained by mass spectrometry analysis m/z=510, calculated target product molecular weight C40H30=510, the compound was confirmed to be C1 (yield: 80%)

Embodiment two (synthetic compound (C16))

Referring to the method described in Example 1, N, N-diphenyl-2-bromoaniline (see Synthesis Example 4) and 2-dianilinophenylboronic acid (see Synthesis Example 14) were used as raw materials to obtain light yellow Powder 1.36 g.

The product obtained by mass spectrometry analysis m/z=488, calculated target product molecular weight C36H28N2=488, the compound was confirmed to be C16 (yield: 83%)

Embodiment three (synthetic compound (C41))

With reference to the method described in Example 1, N, N-diphenyl-2-bromoaniline (see Synthesis Example 4) and 2-(2,2-diphenylvinyl) phenylboronic acid (see Synthesis Implementation) were used as raw materials Example 12), obtain yellow powder 1.51 grams.

The product obtained by mass spectrometry analysis m/z=499, calculated target product molecular weight C38H29N=499, the compound was confirmed to be C41 (yield: 70%)

Embodiment four (synthetic compound (C51))

With reference to the method described in Example 1, N, N-bis(4-phenylphenyl)-p-bromoaniline (see Synthesis Example 6) and 4-(2,2-diphenylvinyl)benzene were used as raw materials Boronic acid (see Synthesis Example 13) to obtain 1.31 grams of yellow powder.

The product obtained by mass spectrometry analysis m/z=651, calculated target product molecular weight C50H37N=652, the compound was confirmed to be C51 (yield: 76%)

Embodiment five (synthetic compound (C59))

With reference to the method described in Example 1, 2,5-bis(2,2-diphenylvinyl)bromobenzene (see Synthesis Example 10) and 4-(2,2-diphenylvinyl)benzene were used as raw materials Boronic acid (see Synthesis Example 13) to obtain 1.89 grams of yellow powder.

The product obtained by mass spectrometry analysis m/z=688, calculated target product molecular weight C54H40=689, the compound was confirmed to be C59 (yield: 67%)

Embodiment six (synthetic compound (C70))

With reference to the method described in Example 1, N, N-bis(4-phenylphenyl)-p-bromoaniline (see Synthesis Example 6) and 2,5-bis(2,2-diphenylethylene) were used as raw materials base) phenylboronic acid (see Synthesis Example 15) to obtain 1.39 grams of yellow powder.

The product obtained by mass spectrometry analysis m/z=829, calculated target product molecular weight C64H47N=830, the compound was confirmed to be C70 (yield: 71%)

Embodiment seven (synthetic compound (C80))

Under the protection of argon, 1.35 grams of 2,5-bis(2,2-diphenylvinyl)bromobenzene (see Synthesis Example 10), 2,5-bis(2,2-diphenylethenyl) ) 1.43 grams of phenylboronic acid (see Synthesis Example 15), 0.04 grams of palladium dichloride, 0.12 grams of triphenylphosphine, 1.4 grams of potassium carbonate, 20 milliliters of deionized water, 20 milliliters of absolute ethanol, and 30 milliliters of toluene Add it into a 250 ml three-necked flask, stir, and heat to reflux, and the reaction time is not less than 24 hours. After the reaction, the organic phase was separated and purified by column chromatography to obtain 1.10 g of a bright yellow solid.

The product obtained by mass spectrometry analysis m/z=866, calculated target product molecular weight C68H50=866, the compound was confirmed to be C80 (yield: 49%)

Embodiment eight (synthetic compound (C81))

With reference to the method described in Example 7, the raw material is 2-(2,2-diphenylvinyl)-5-diphenylaminobromobenzene (see Synthesis Example 9) and 2-(2,2-diphenylethylene base)-5-dianilinophenylboronic acid (see Synthesis Example 17) to obtain 1.79 g of yellow powder.

The product obtained by mass spectrometry analysis m/z=844, calculated target product molecular weight C64H48N2=845, the compound was confirmed to be C81 (yield: 52%)

Embodiment nine (synthetic compound (C104))

With reference to the method described in Example 1, 2,4-bis(2,2-diphenylethenyl) bromobenzene (see Synthesis Example 11) and 4-(2,2-diphenylethenyl) were used as raw materials Phenylboronic acid (see Synthesis Example 13) to obtain 2.01 grams of yellow powder.

The product obtained by mass spectrometry analysis m/z=688, calculated target product molecular weight C54H40=689, the compound was confirmed to be C104 (yield: 70%)

Embodiment ten (synthetic compound (C114))

With reference to the method described in Example 7, 2,4-bis(2,2-diphenylvinyl)bromobenzene (see Synthesis Example 11) and 2,4-bis(2,2-diphenyl) were used as raw materials Vinyl) phenylboronic acid (see Synthesis Example 16) to obtain 1.32 grams of yellow powder.

The product obtained by mass spectrometry analysis m/z=866, calculated target product molecular weight C68H50=866, the compound was confirmed to be C114 (yield: 51%)

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

Preferred embodiment of the device:

The typical structure of an OLED device is: substrate/anode/hole transport layer (HTL)/organic light-emitting layer/electron transport layer (ETL)/cathode.

The substrate is transparent, which can be glass or flexible substrate. The flexible substrate is made of polyester and polyimide compounds; the anode layer can be made of inorganic materials or organic conductive polymers. Inorganic materials are generally Metal oxides such as indium tin oxide (hereinafter referred to as ITO), zinc oxide, tin-zinc oxide, or metals with higher work functions such as gold, copper, and silver, the optimal choice is ITO, and the organic conductive polymer is preferably polythiophene/ Sodium polyvinylbenzene sulfonate (hereinafter referred to as PEDOT:PSS), polyaniline (hereinafter referred to as PANI) is a material; the cathode layer generally uses metals with low work functions such as lithium, magnesium, calcium, strontium, aluminum, and indium Or they and copper, gold, silver alloy, or the electrode layer that metal and metal fluoride form alternately, the present invention is preferably sequential Mg:Ag alloy layer, Ag layer and successive LiF layer, Al layer; Hole transport layer Generally, triarylamine materials are used, and the present invention is preferably N, N'-di-(1-naphthyl)-N, N'-diphenyl-1,1-biphenyl-4,4-diamine (NPB ); the electron transport layer is generally a metal-organic complex, preferably as three (8-hydroxyquinoline) aluminum, three (8-hydroxyquinoline) gallium, (salicylaldehyde acetal amine phenol)-(8-hydroxyquinoline) phenanthroline) gallium(III) (hereinafter referred to as Alq ₃ , Gaq ₃ , Ga(Saph-q) respectively), or o-phenanthrolines, such as 4,7-diphenyl-1,10-phenanthrole Phenyl (hereinafter referred to as Bphen), etc., the organic light-emitting layer can generally use small molecule materials, and can be doped with fluorescent materials or phosphorescent dyes. The organic light-emitting layer of the present invention includes the organic light-emitting material proposed by the present invention, which can directly emit light. It can also be used as a dye doped in the corresponding host material to emit light, and the preferred host material is Alq ₃ , Gaq ₃ , Ga(Saph-q).

Prepare a series of organic electroluminescent devices of the present invention according to the following methods:

(1) Use cleaning agent, deionized water and organic solution to clean the glass substrate with anode in several steps;

(2) Evaporating the hole transport layer of the device by vacuum evaporation;

(3) Continue to vapor-deposit the light-emitting layer comprising the red light material of the present invention;

(4) Continue to evaporate the electron transport layer of the device;

(5) Prepare a metal cathode by evaporation or sputtering.

Embodiment 11 Preparation of Devices OLED-1～OLED-2

ITO/NPB(40nm)/C80(15or30nm)/BPhen(40nm)/Mg:Ag/Ag

Preparation of OLED-1: The glass plate coated with the ITO transparent conductive layer was ultrasonically treated in a commercial cleaning agent, rinsed in deionized water, ultrasonically degreased in acetone:ethanol mixed solvent, and baked in a clean environment until completely removed Moisture, irradiated with a UV light cleaner for 10 minutes, and bombarded the surface with a low-energy positive ion beam.

Put the above-mentioned glass substrate with an anode in a vacuum chamber, evacuate to 1×10 ^-5 ~ 9×10 ^-3 Pa, continue to evaporate NPB on the above-mentioned anode layer as a hole transport layer, and the evaporation rate is 0.1nm/s, and the evaporated film thickness is 40nm;

On the hole transport layer, continue to evaporate one layer of compound (C80) of the present invention as the light-emitting layer of the device, the evaporation rate is 0.1nm/s, and the evaporation film thickness is 15nm;

Continue to evaporate a layer of BPhen material as the electron transport layer of the device, the evaporation rate is 0.1nm/s, and the total evaporation film thickness is 40nm;

Finally, a Mg:Ag alloy layer and an Ag layer are sequentially evaporated on the above-mentioned electron transport layer as the cathode layer of the device, wherein the evaporation rate of the Mg:Ag alloy layer is 2.0-3.0nm/s, the thickness is 100nm, and the Ag layer The evaporation rate is 0.3nm/s, and the thickness is 100nm.

OLED-2 was prepared according to the above method, except that the vapor-deposited film thickness of the compound (C80) was changed to 30nm. The performance of the device is shown in Table 1:

Table 1: part number Device Structure Luminescence wavelength nm Turn on voltage V Brightnesscd/m2 Efficiency cd/A OLED-1 ITO/NPB(40nm)/C80(15nm)/BPhen(40nm)/Mg:Ag/Ag 468 3.27 18977 3.71 OLED-2 ITO/NPB(40nm)/C80(30nm)/BPhen(40nm)/Mg:Ag/Ag 468 3.88 16426 3.0

Example 12 Preparation of devices OLED-3, OLED-4 and OLED-5

The method is the same as in the eleventh embodiment, except that the materials of the light-emitting layer are replaced by C70, C81, and C114, and the film thicknesses of the layers are 20nm, 25nm, and 30nm, respectively. The performance of the device is detailed in Table 2:

Table 2 part number Device Structure Turn on voltage V Brightnesscd/m2 Efficiency cd/A OLED-3 ITO/NPB(40nm)/C70(20nm)/BPhen(40nm)/Mg:Ag/Ag 3.02 14520 2.3 OLED-4 ITO/NPB(40nm)/C81(25nm)/BPhen(40nm)/Mg:Ag/Ag 2.90 17523 4.2 OLED-5 ITO/NPB(40nm)/C114(30nm)/BPhen(40nm)/Mg:Ag/Ag 3.33 14000 1.9

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

Claims (6)

1. A compound whose structure is as follows: 2. A compound whose structure is as follows:

3. A compound whose structure is shown in C80 or C81 as follows:

4. A compound whose structure is as follows:

5. A compound whose structure is as follows:

6. An organic electroluminescent device, comprising an anode, a cathode and an organic functional layer, wherein at least one layer in the organic functional layer comprises a single compound represented by the following structural formula:

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