Compound and application thereof
阅读说明：本技术 一种化合物及其应用 (Compound and application thereof ) 是由 李之洋 黄鑫鑫 张辉 于 2019-08-26 设计创作，主要内容包括：本发明涉及一种化合物及其应用,所述化合物具有式(1)所示的结构；所述化合物应用于有机电致发光器件；所述有机电致发光器件包括第一电极、第二电极以及位于第一电极和第二电极之间的有机层,所述有机层中含有式(1)所示的化合物。本发明通过特定的吸电与供电基团的搭配使用,使得分子整体的HOMO与LUMO能级与其他功能层相匹配,降低了载流子的传输壁垒,在通过引入高迁移率的杂芳基取代基团,使得本发明材料具备相比较已有材料,能够使器件具有更低的电压和更高的效率。(The invention relates to a compound and application thereof, wherein the compound has a structure shown in a formula (1); the compound is applied to an organic electroluminescent device; the organic electroluminescent device comprises a first electrode, a second electrode and an organic layer positioned between the first electrode and the second electrode, wherein the organic layer contains a compound shown in a formula (1). According to the invention, through the matching use of specific electricity absorption and supply groups, the energy levels of HOMO and LUMO of the whole molecule are matched with other functional layers, the transmission barrier of current carriers is reduced, and compared with the existing material, the material provided by the invention has the advantages that the voltage of a device is lower and the efficiency is higher by introducing a heteroaryl substituent group with high mobility.)
1. A compound having a structure represented by formula (1);
in the formula (1), X1And X2One is N and the other is CR5；
The R is1、R2、R3、R4And R5Each independently selected from hydrogen atom, substituted or unsubstituted C1EC12 alkyl, substituted or unsubstituted C3-C12 cycloalkyl, substituted or unsubstituted C1-C12 alkoxy, halogen, cyano, nitro, hydroxyl, silyl, amino, substituted or unsubstituted C6-C30 aryl, and substituted or unsubstituted C3-C30 heteroaryl, wherein R is selected from the group consisting of1、R2、R3、R4And R5Wherein two adjacent substituents are fused to form a ring or are not fused to form a ring;
in the formula (1), L1、L2And L3Each independently is any one of single bond, substituted or unsubstituted C6-C30 arylene, substituted or unsubstituted C3-C30 heteroarylene;
in the formula (1), Ar is1And Ar2Each independently is any one of substituted or unsubstituted C6-C30 aryl and substituted or unsubstituted C3-C30 heteroaryl;
in the formula (1), Ar3Any one selected from the following groups:
z is1、Z2、Z3、Z4、Z5、Z6、Z7And Z8Each independently selected from N or CRcAnd at least one term is N;
m is an integer of 1-5, and a is an integer of 1-m;
n is an integer of 1-8, and b is an integer of 1-n;
s is an integer of 1-7, and d is an integer of 1-s;
c is an integer of 1-7;
the R isa、Rb、RcAnd RdEach independently selected from any one of hydrogen atom, halogen, cyano, C1-C12 alkyl, C1-C12 alkoxy, C6-C30 aryl and C3-C30 heteroaryl;
wherein the dotted line represents the attachment site of the group;
when the above groups have substituents, the substituents are respectively and independently selected from cyano, halogen, alkyl or cycloalkyl of C1-C10, alkenyl of C2-C6, alkoxy or thioalkoxy of C1-C6, nitro, amino, carbonyl, carboxyl, ester group, monocyclic aryl or condensed ring aryl of C6-C30, monocyclic heteroaryl or condensed ring heteroaryl of C3-C30.
2. The compound of claim 1, wherein X is1Is CR5，X2Is N.
3. The compound of claim 1, wherein Z is1、Z2、Z3、Z4、Z5、Z6、Z7And Z8And only one of them is N.
4. A compound of claim 1, wherein R isa、Rb、RcAnd RdEach independently selected from any one of a hydrogen atom, a phenyl group, a cyano group or a methoxy group.
5. The compound of claim 1, wherein Ar is3Any one selected from the following groups:
z is1、Z2、Z3、Z4、Z5、Z6、Z7And Z8Each independently selected from N or CH, and the Z1、Z2、Z3、Z4、Z5、Z6、Z7And Z8And only one of them is N;
wherein Ph represents a phenyl group and the dotted line represents the attachment site of the group.
6. The compound of claim 1, wherein Ar is Ar3Any one selected from the following groups:
wherein the dotted line represents the attachment site of the group.
7. A compound according to any one of claims 1 to 6 wherein Ar is1And Ar2Each independently selected from any one of phenyl, naphthyl, dibenzothienyl, biphenyl or fluorenyl.
8. The compound of claim 1, wherein L is1、L2And L3Each independently selected from a single bond or substituted or unsubstituted C6-C30 arylene; preferably a single bond or a C6-C30 arylene group; further preferred is a single bond or phenylene group.
9. The compound of claim 1, having any one of the following structures P1-P91:
10. use of a compound according to any one of claims 1 to 9 in an organic electroluminescent device;
preferably, the compounds are used as light-emitting layer materials in the organic electroluminescent device, preferably as light-emitting layer host materials.
11. An organic electroluminescent element comprising a first electrode, a second electrode and an organic layer between the first electrode and the second electrode, wherein the organic layer contains the compound according to any one of claims 1 to 9.
Technical Field
The invention relates to the technical field of organic electroluminescence, in particular to a compound and application thereof.
Background
In recent years, Organic Light Emitting Diodes (OLEDs) have been developed very rapidly, and have a place in the field of information display, which is mainly benefited from the fact that OLED devices can prepare full-color display devices using three primary colors of high saturation, red, green and blue, and can realize bright, light, thin and soft colors without additional backlight sources.
The Organic Light Emitting Diode (OLED) device plays an important role in a thin-layer structure containing various organic functional materials, and common organic functional materials comprise a light emitting layer material, an electron blocking layer material, an electron transport layer material, a hole blocking layer material, a hole transport layer material and the like. After the power is switched on, electrons and holes are respectively injected and transmitted to the light-emitting layer and are recombined to generate excitons, so that light is emitted. Therefore, the research on organic functional materials in OLED devices is a key research topic for those skilled in the art.
At present, researchers have developed various organic functional materials for various specific device structures, which play roles in improving carrier mobility, regulating carrier balance, breaking through electroluminescence efficiency, and delaying device attenuation.
Conventional fluorescent emitters emit light primarily using singlet excitons generated upon recombination of holes and electrons, and such emitters are still used in various OLED devices. In addition, a phosphorescent emitter, that is, a material which can emit light by using both triplet excitons and singlet excitons, such as an iridium complex or the like, is also included. Most importantly, the thermal excitation delayed fluorescence (TADF) technology can still effectively utilize triplet excitons to realize higher luminous efficiency by promoting the conversion of the triplet excitons to the singlet excitons without adopting a metal complex, and the thermal excitation sensitized fluorescence (TASF) technology is to adopt a TADF material to sensitize a luminous body in an energy transfer manner to realize higher luminous efficiency, so that the TADF material has a wide application prospect in the field of OLEDs.
Although various organic functional layer materials have been developed, nowadays, the requirements of people on the performance of the OLED device are higher and higher, and the existing organic functional materials cannot be applied to new OLED devices with higher performance. Therefore, there is a need in the art to develop a wider variety of organic functional materials, which can improve the light emitting efficiency and reduce the driving voltage when applied to OLED devices.
Disclosure of Invention
The invention aims to provide a compound which can balance hole and electron transmission, maintain a better carrier transmission rate and meet the requirement of continuously improving the photoelectric performance of an OLED device.
In order to achieve the purpose, the invention adopts the following technical scheme:
the invention provides a compound, which has a structure shown in a formula (1);
in the formula (1), X1And X2One is N and the other is CR5；
The R is1、R2、R3、R4And R5Each independently selected from any one of a hydrogen atom, a substituted or unsubstituted C1-C12 alkyl group, a substituted or unsubstituted C3-C12 cycloalkyl group, a substituted or unsubstituted C1-C12 alkoxy group, halogen, a cyano group, a nitro group, a hydroxyl group, a silane group, an amino group, a substituted or unsubstituted C6-C30 aryl group and a substituted or unsubstituted C3-C30 heteroaryl group, wherein R is selected from the group consisting of1、R2、R3、R4And R5Condensed between two adjacent substituentsA ring is formed or not fused; illustratively, R1And R2May be fused to form a ring, or may be two independent substituents.
In the formula (1), L1、L2And L3Each independently is any one of single bond, substituted or unsubstituted C6-C30 arylene, substituted or unsubstituted C3-C30 heteroarylene;
in the formula (1), Ar is1And Ar2Each independently is any one of substituted or unsubstituted C6-C30 aryl and substituted or unsubstituted C3-C30 heteroaryl;
in the formula (1), Ar3Any one selected from the following groups:
z is1、Z2、Z3、Z4、Z5、Z6、Z7And Z8Each independently selected from N or CRcAnd at least one term is N;
m is an integer of 1-5, such as 1, 2,3, 4, 5, a is an integer of 1-m;
n is an integer of 1-8, such as 1, 2,3, 4, 5, 6, 7, 8, and b is an integer of 1-n;
s is an integer of 1-7, such as 1, 2,3, 4, 5, 6, 7, and d is an integer of 1-s;
c is an integer of 1-7, such as 1, 2,3, 4, 5, 6, 7;
the R isa、Rb、RcAnd RdEach independently selected from any one of hydrogen atom, halogen, cyano, C1-C12 alkyl, C1-C12 alkoxy, C6-C30 aryl and C3-C30 heteroaryl;
wherein the dotted line represents the attachment site of the group;
when the above groups have substituents, the substituents are respectively and independently selected from cyano, halogen, alkyl or cycloalkyl of C1-C10, alkenyl of C2-C6, alkoxy or thioalkoxy of C1-C6, nitro, amino, carbonyl, carboxyl, ester group, monocyclic aryl or condensed ring aryl of C6-C30, monocyclic heteroaryl or condensed ring heteroaryl of C3-C30.
In the present invention, Ra、Rb、RcAnd RdIndependently represents a group other than a specific one, and illustratively, when m is 2, a is an integer of 1 to 2, then a is 1 or 2, i.e., RaMay be R1Or may be R2That is, when the mother ring is substituted with two RaWhen two R are presentaMay be the same or different. Rb、RcAnd RdThe same is true.
In the present invention, the representation of a solid or dashed line crossing a ring indicates that the access site of the group can be any bondable position on the ring being crossed.
The material of the invention is a parent nucleus structure taking triphenyl as a center, wherein a substituent group must contain a 2-nitrogen atom electricity-absorbing group (quinazoline or quinoxaline) to ensure the LUMO energy level of a molecular structure, and simultaneously, the molecular structure must contain an arylamine group to ensure the HOMO energy level of a molecule, and in addition, heteroaryl (Ar) with good carrier transport performance is introduced into a third substituent group3) Heteroaryl (Ar) of specific structures of these classes3) The compound is matched with quinazoline or quinoxaline and arylamine groups, so that the molecules keep better carrier transmission rate while balancing hole and electron transmission.
In summary, the compound of the present invention matches the HOMO and LUMO energy levels of the whole molecule with other functional layers by the above-mentioned matching use of the fixed electron-withdrawing and electron-supplying groups, and reduces the transport barrier of carriers, and compared with the existing materials, the material of the present invention has the advantages of lower voltage and higher efficiency by introducing the heteroaryl substituent group with high mobility.
The substituted or unsubstituted C1-C12 alkyl group, preferably C1-C10 alkyl group, more preferably C1-C6 alkyl group, includes, for example: methyl, ethyl, n-propyl, isopropyl, n-butyl, n-hexyl, n-octyl, isobutyl, tert-butyl, cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl and the like.
Substituted or unsubstituted C6-C30 aryl groups, preferably C6-C20 aryl groups, in the present invention preferably include phenyl, biphenyl, terphenyl, naphthyl, anthryl, phenanthryl, indenyl, fluorenyl and derivatives thereof, fluoranthryl, triphenylenyl, pyrenyl, perylenyl, perylene, and the like,Phenyl and tetracenyl. The biphenyl group is selected from the group consisting of 2-biphenyl, 3-biphenyl, and 4-biphenyl; the terphenyl group includes p-terphenyl-4-yl, p-terphenyl-3-yl, p-terphenyl-2-yl, m-terphenyl-4-yl, m-terphenyl-3-yl and m-terphenyl-2-yl; the naphthyl group includes a 1-naphthyl group or a 2-naphthyl group; the anthracene group is selected from 1-anthracene group, 2-anthracene group and 9-anthracene group; the fluorenyl group is selected from the group consisting of 1-fluorenyl, 2-fluorenyl, 3-fluorenyl, 4-fluorenyl, and 9-fluorenyl; the fluorenyl derivative is selected from 9,9 '-dimethylfluorene, 9' -spirobifluorene and benzofluorene; the pyrenyl is selected from 1-pyrenyl, 2-pyrenyl and 4-pyrenyl; the tetracenyl is selected from the group consisting of 1-tetracenyl, 2-tetracenyl, and 9-tetracenyl.
In the present invention, a substituted or unsubstituted C3-C30 heteroaryl group, preferably a C6-C20 heteroaryl group, preferably the heteroaryl group is a furyl group, a thienyl group, a pyrrolyl group, a benzofuryl group, a benzothienyl group, an isobenzofuryl group, an indolyl group, a dibenzofuryl group, a dibenzothienyl group, a carbazolyl group and a derivative thereof, wherein the carbazolyl derivative is preferably 9-phenylcarbazole, 9-naphthylcarbazole benzocarbazole, dibenzocarbazole, or indolocarbazole.
Preferably, said X1Is CR5，X2Is N.
Preferably, Z is1、Z2、Z3、Z4、Z5、Z6、Z7And Z8And only one of them is N.
Preferably, said R isa、Rb、RcAnd RdEach independently selected from a hydrogen atom, phenyl, cyano orAny one of methoxy groups.
Preferably, Ar is3Any one selected from the following groups:
z is1、Z2、Z3、Z4、Z5、Z6、Z7And Z8Each independently selected from N or CH, and the Z1、Z2、Z3、Z4、Z5、Z6、Z7And Z8And only one of them is N;
wherein Ph represents a phenyl group and the dotted line represents the attachment site of the group.
Preferably, Ar is3Any one selected from the following groups:
wherein the dotted line represents the attachment site of the group.
Preferably, Ar is1And Ar2Each independently selected from any one of phenyl, naphthyl, dibenzothienyl, biphenyl or fluorenyl.
Preferably, said L1、L2And L3Each independently selected from a single bond or substituted or unsubstituted C6-C30 arylene; preferably a single bond or a C6-C30 arylene group; further preferred is a single bond or phenylene group.
Preferably, the compound has any one of the following structures shown as P1 to P91:
the second purpose of the invention is to provide the application of the compound in the first purpose, and the compound is applied to an organic electroluminescent device.
Preferably, the compounds are used as light-emitting layer materials in the organic electroluminescent device, preferably as light-emitting layer host materials.
It is a further object of the present invention to provide an organic electroluminescent device comprising a first electrode, a second electrode, and an organic layer between the first electrode and the second electrode, the organic layer containing a compound according to one of the objects.
In one embodiment, the organic layer may further include a hole transport region, a light emitting layer, an electron transport region.
In one embodiment, a substrate may be used below the first electrode or above the second electrode. The substrate is a glass or polymer material having excellent mechanical strength, thermal stability, water resistance, and transparency. In addition, a Thin Film Transistor (TFT) may be provided on a substrate for a display.
The first electrode may be used as the first electrode by sputtering or deposition on the substrateThe material of the electrodes. When the first electrode is used as an anode, Indium Tin Oxide (ITO), Indium Zinc Oxide (IZO), tin dioxide (SnO) may be used2) And transparent conductive oxide materials such as zinc oxide (ZnO), and any combination thereof. When the first electrode is used as a cathode, a metal or an alloy such as magnesium (Mg), silver (Ag), aluminum (Al), aluminum-lithium (Al-Li), calcium (Ca), magnesium-indium (Mg-In), magnesium-silver (Mg-Ag), or any combination thereof can be used.
The organic layer may be formed on the electrode by vacuum thermal evaporation, spin coating, printing, or the like. The compounds used as the organic layer may be small organic molecules, large organic molecules, and polymers, and combinations thereof.
The hole transport region is located between the anode and the light emitting layer. The hole transport region may be a Hole Transport Layer (HTL) of a single layer structure including a single layer containing only one compound and a single layer containing a plurality of compounds. The hole transport region may also be a multilayer structure including at least one of a Hole Injection Layer (HIL), a Hole Transport Layer (HTL), and an Electron Blocking Layer (EBL).
The material of the hole transport region may be selected from, but is not limited to, phthalocyanine derivatives such as CuPc, conductive polymers or polymers containing conductive dopants such as polyphenylenevinylene, polyaniline/dodecylbenzenesulfonic acid (Pani/DBSA), poly (3, 4-ethylenedioxythiophene)/poly (4-styrenesulfonate) (PEDOT/PSS), polyaniline/camphorsulfonic acid (Pani/CSA), polyaniline/poly (4-styrenesulfonate) (Pani/PSS), aromatic amine derivatives such as compounds shown below in HT-1 to HT-34; or any combination thereof.
The hole injection layer is located between the anode and the hole transport layer. The hole injection layer may be a single compound material or a combination of a plurality of compounds. For example, the hole injection layer may employ one or more compounds of HT-1 to HT-34 described above, or one or more compounds of HI-1 to HI-3 described below; one or more of the compounds HT-1 to HT-34 may also be used to dope one or more of the compounds HI1 to HI3 described below.
The light-emitting layer includes a light-emitting dye (i.e., dopant) that can emit different wavelength spectra, and may also include a Host material (Host). The light emitting layer may be a single color light emitting layer emitting a single color of red, green, blue, or the like. The single color light emitting layers of a plurality of different colors may be arranged in a planar manner in accordance with a pixel pattern, or may be stacked to form a color light emitting layer. When the light emitting layers of different colors are stacked together, they may be spaced apart from each other or may be connected to each other. The light-emitting layer may be a single color light-emitting layer capable of emitting red, green, blue, or the like at the same time.
According to different technologies, the luminescent layer material can be different materials such as fluorescent electroluminescent material, phosphorescent electroluminescent material, thermal activation delayed fluorescent luminescent material, and the like. In an OLED device, a single light emitting technology may be used, or a combination of a plurality of different light emitting technologies may be used. These technically classified different luminescent materials may emit light of the same color or of different colors.
In one aspect of the invention, the light-emitting layer employs phosphorescent electroluminescent technology. The host material of the light emitting layer is selected from, but not limited to, one or more of GPH-1 to GPH-80.
In one aspect of the invention, the light-emitting layer employs phosphorescent electroluminescent technology. The phosphorescent dopant of the light emitting layer thereof may be selected from, but not limited to, a combination of one or more of RPD-1 to RPD-28 listed below.
The OLED organic material layer may further include an electron transport region between the light emitting layer and the cathode. The electron transport region may be an Electron Transport Layer (ETL) of a single-layer structure including a single-layer electron transport layer containing only one compound and a single-layer electron transport layer containing a plurality of compounds. The electron transport region may also be a multilayer structure including at least one of an Electron Injection Layer (EIL), an Electron Transport Layer (ETL), and a Hole Blocking Layer (HBL).
In one aspect of the invention, the electron transport layer material may be selected from, but is not limited to, the combination of one or more of ET-1 through ET-57 listed below.
An electron injection layer may also be included in the device between the electron transport layer and the cathode, the electron injection layer materials including, but not limited to, combinations of one or more of the following.
Liq、LiF、NaCl、CsF、Li2O、Cs2CO3、BaO、Na、Li、Ca。
The cathode is metal, metal mixture or oxide such as magnesium silver mixture, LiF/Al, ITO, etc.
Compared with the prior art, the invention has the following beneficial effects:
the material of the invention is a parent nucleus structure with the triphenyl as the center, wherein a substituent group must contain an electricity absorbing group with 2 nitrogen atoms, the LUMO energy level of a molecular structure is ensured, meanwhile, the molecular structure must contain an arylamine group, the HOMO energy level of the molecule is ensured, and heteroaryl (Ar) with good carrier transmission performance is introduced into a third substituent group3) So that the molecules can balance the transmission of holes and electrons and keep better carrier transmission rate.
In summary, the compound of the present invention matches the HOMO and LUMO energy levels of the whole molecule with other functional layers by the above-mentioned matching use of the fixed electron-withdrawing and electron-supplying groups, and reduces the transport barrier of carriers, and compared with the existing materials, the material of the present invention has the advantages of lower voltage and higher efficiency by introducing the heteroaryl substituent group with high mobility.
Detailed Description
The technical solution of the present invention is further explained by the following embodiments. It should be understood by those skilled in the art that the examples are only for the understanding of the present invention and should not be construed as the specific limitations of the present invention.
A representative synthesis method of the compound represented by the formula (1) of the present invention is as follows:
wherein X is halogen, specifically chlorine, bromine or iodine, -OTF is CF3SO3-。
The third and fourth reactions are common Suzuki or Buchwald-Hartwig coupling reactions according to L2、L3、Ar1、Ar2And Ar3The specific structure of (a) is different, and different raw materials can be selected, and the specific structure can be seen in the synthesis examples below.
The method for synthesizing the compound of formula (1) is not limited to the above method, and those skilled in the art can select other synthetic methods according to the prior art, and the present invention is not limited thereto.
More specifically, for a specific substituent, the following two specific synthetic methods can be selected:
the method comprises the following steps:
the method 2 comprises the following steps:
compounds of the synthetic methods not mentioned in the following synthetic examples of the present invention are all commercially available starting products. The solvents and reagents used in the present invention, such as methylene chloride, ethanol, quinazoline, quinoxaline and other chemical reagents, can be purchased from domestic chemical product markets, such as from national drug group reagents, TCI, shanghai beide pharmaceuticals, and carbofuran reagents. In addition, they can be synthesized by a known method by those skilled in the art.
Synthesis example 1
Synthesis of Compound P1
Adding S1(30mmol), 2-chloro-4-phenylquinazoline (60mmol), potassium carbonate (45mmol), dioxane (200mL), palladium tetrakis (triphenylphosphine) (0.3mmol) and 50mL of water into a reaction bottle, heating to reflux for reaction for 3h, monitoring by TLC to complete the reaction, pouring the reaction solution into water for filtration, concentrating after dichloro extraction, and recrystallizing with toluene to obtain an intermediate A.
Adding A (15mmol), diphenylamine (16mmol), sodium tert-butoxide (20mmol), tris (dibenzylideneacetone) dipalladium (0.15mmol), tri-tert-butylphosphine (0.3mmol) and 200mL of xylene into a reaction bottle, heating to 120 ℃ for reaction for 6h, monitoring the reaction by TLC (thin layer chromatography), cooling, directly filtering, and recrystallizing a filter cake by xylene to obtain the compound P1.
Synthesis example 2:
synthesis of Compound P9
The difference from Synthesis example 1 is that 2-chloro-4-phenylquinazoline was replaced with an equivalent amount of 2-chloro-3-phenylquinoxaline to give compound P9.
Synthesis example 3:
synthesis of Compound P17
Adding S2(30mmol), 2-chloro-4-phenylquinazoline (60mmol), potassium carbonate (45mmol), dioxane (200mL), palladium tetrakis (triphenylphosphine) (0.3mmol) and 50mL of water into a reaction bottle, heating to reflux for reaction for 3h, monitoring by TLC to complete the reaction, pouring the reaction solution into water for filtration, concentrating after dichloro extraction, and recrystallizing with toluene to obtain an intermediate A.
Adding A (20mmol) and pyridine (40mmol) into 200mL dichloromethane, cooling to-5 ℃, dropwise adding trifluoromethanesulfonic anhydride (40mmol), reacting at room temperature for 1h after dropwise adding, monitoring by TLC for complete reaction, adding water, quenching, and extracting and concentrating dichloromethane to obtain an intermediate B.
Adding B (15mmol), dibenzothiophene-4-boric acid (15mmol), potassium carbonate (20mmol), dioxane (150mL), palladium (0.15mmol) and 30mL of water into a reaction bottle, heating until reflux reaction is completed for 3h, monitoring by TLC, pouring the reaction liquid into water, filtering, performing dichloro extraction, concentrating, and recrystallizing toluene to obtain an intermediate C.
Adding C (10mmol), diphenylamine (12mmol), sodium tert-butoxide (15mmol), tris (dibenzylideneacetone) dipalladium (0.1mmol), tri-tert-butylphosphine (0.2mmol) and 150mL of xylene into a reaction bottle, heating to 120 ℃ for reaction for 6h, monitoring the reaction by TLC, cooling, directly filtering, and recrystallizing a filter cake by xylene to obtain the compound P17.
Synthesis example 4:
synthesis of Compound P20
Adding C (10mmol), triphenylamine-4-boric acid (12mmol), potassium phosphate (15mmol), dioxane (150mL), tris (dibenzylideneacetone) dipalladium (0.1mmol) and 2-dicyclohexylphosphine-2 ',6' -dimethoxybiphenyl (S-phos) (0.2mmol) into a reaction bottle, heating until reflux reaction is carried out for 3h, monitoring by TLC to complete the reaction, pouring the reaction solution into water, filtering, and recrystallizing filter cake xylene to obtain the compound P20.
Synthesis example 5:
synthesis of Compound P53
The difference from synthetic example 3 was that dibenzothiophene-4-boronic acid was replaced with dibenzofuran-4-boronic acid in an equivalent amount to obtain compound P53.
Synthesis example 6:
synthesis of Compound P57
Adding S3(30mmol), potassium carbonate (50mmol), DMF (200mL) and carbazole (30mmol) into a reaction bottle, heating until reflux reaction is carried out for 4h, monitoring by TLC to complete the reaction, cooling, adding the reaction solution into water, filtering, washing filter cake with ethanol, and drying once to obtain the intermediate A.
A (20mmol), Bipinacol borate (30mmol) and ([1,1' -bis (diphenylphosphino) ferrocene]Palladium dichloride) (pd (dppf) Cl2) (0.2mmol), potassium acetate (30mmol) and dioxane (200mL) are added into a reaction bottle, after reflux reaction for 3h, water and dichloromethane are added for extraction, and the organic phase is concentrated to obtain an intermediate B.
Adding B (15mmol), 2-chloro-4-phenylquinazoline (15mmol), potassium carbonate (20mmol), dioxane (150mL), palladium tetrakis (triphenylphosphine) (0.15mmol) and 30mL of water into a reaction bottle, heating until reflux reaction is carried out for 3h, monitoring by TLC to complete the reaction, pouring the reaction solution into water for filtration, concentrating after dichloro extraction, and recrystallizing with toluene to obtain an intermediate C.
Adding C (10mmol), diphenylamine (12mmol), sodium tert-butoxide (15mmol), tris (dibenzylideneacetone) dipalladium (0.1mmol), tri-tert-butylphosphine (0.2mmol) and 150mL of xylene into a reaction bottle, heating to 120 ℃ for reaction for 6h, monitoring the reaction by TLC, cooling, directly filtering, and recrystallizing a filter cake by xylene to obtain the compound P57.
Synthesis example 7:
synthesis of Compound P65
The difference from synthetic example 6 was that carbazole was replaced with 9H-pyrido [2,3-B ] indole in an equivalent amount to obtain compound P65.
The present invention exemplarily provides specific synthetic methods for the above compounds, and compounds for which specific synthetic methods are not given in the following examples are also prepared by similar methods, and can be obtained only by replacing raw materials, which are not described herein again, or can be prepared by other methods in the prior art by those skilled in the art.
To verify the certainty of the molecular structure of the compound of formula (1) used in the examples of the present invention, we confirmed it by elemental analysis (seimeflight FLASH 2000CHNS/O organic element analyzer) and mass spectrometry information (ZAB-HS type mass spectrometer manufactured by Micromass corporation, uk), and the results are shown in table 1.
TABLE 1
Example 1
The embodiment provides an organic electroluminescent device, and the specific preparation method 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 ITO anode in a vacuum chamber, and vacuumizing to<1×10-5Pa, performing vacuum thermal evaporation on the anode layer film in sequence to obtain a 10nm HT-4: HI-3(97/3, w/w) mixture as a hole injection layer, a 60nm compound HT-4 as a hole transport layer, a 40nm compound P1: RPD-8(100:3, w/w) binary mixture as a light emitting layer, a 25nm compound ET-46: ET-57(50/50, w/w) mixture as an electron transport layer, 1nm LiF as an electron injection layer, and 150nm metal aluminum as a cathode. The total evaporation rate of all the organic layers and LiF is controlled at 0.1 nm/s, and the evaporation rate of the metal electrode is controlled at 1 nm/s.
Examples 2-9 differ from example 1 only in that compound P1 was replaced by another compound, as specified in table 2.
Comparative example 1
The difference from example 1 is that compound P1 is replaced by compound C1 (see patent KR1020150122343A for details).
Comparative example 2
The difference from example 8 is that compound P85 was replaced by compound C2 (see patent KR1020110041727A for details).
Comparative example 3
The difference from example 1 is that compound P1 was replaced by compound C3 (prepared by a prior art synthetic method).
And (3) performance testing:
(1) the organic electroluminescent devices prepared in examples and comparative examples were measured for driving voltage and current efficiency and lifetime of the devices at the same luminance using a PR 750 type photoradiometer of Photo Research, a ST-86LA type luminance meter (photoelectric instrument factory of university of beijing), and a Keithley4200 test system. Specifically, the voltage was raised at a rate of 0.1V per second, and it was determined that the luminance of the organic electroluminescent device reached 3000cd/m2The current density is measured at the same time as the driving voltage; the ratio of the brightness to the current density is the current efficiency;
(2) the life test of LT95 is as follows: using ST-86LA type luminance meter (Beijing university photoelectric apparatus factory) at 10000cd/m2The luminance drop of the organic electroluminescent device was measured to be 9500cd/m by maintaining a constant current at luminance2Time in hours.
The results of the performance tests are shown in table 2.
TABLE 2
The results in Table 2 show that the novel organic material provided by the invention can be used for an organic electroluminescent device, can effectively reduce the take-off and landing voltage and improve the current efficiency, and is a red light main body material with good performance, wherein the driving voltage is less than or equal to 3.9V, the current efficiency is more than or equal to 16.1cd/A, and the service life of LT95 is more than or equal to 58 h.
Comparative example 1 compared with example 1, the luminescent host material was different only in that it did not contain arylamine groups, the device performance was significantly reduced, the driving voltage was 4.5V, and the current efficiency was 15.5 cd/a.
Compared with example 8, the luminescent host material of comparative example 2 is different from that of example 8 only in that no quinazoline group is contained, the device performance is obviously reduced, the driving voltage is 4.2V, and the current efficiency is 15.9 cd/A.
Comparative example 3 compared to example 1, the luminescent host material only differs by having only one quinazoline group (i.e. does not contain Ar)3) The device performance was reduced, the drive voltage was 3.8V, and the current efficiency was 13.9 cd/A.
The above comparative results prove that the quinazoline or quinoxaline, the arylamine group and the heteroaryl (Ar) with a specific structure in the compound provided by the invention3) The three substituent groups are mutually matched, so that when the compound is used for an organic electroluminescent device, the luminous efficiency can be improved, and the driving voltage can be reduced.
The present invention is illustrated in detail by the examples described above, but the present invention is not limited to the details described above, i.e., it is not intended that the present invention be implemented by relying on the details described above. It should be understood by those skilled in the art that any modification of the present invention, equivalent substitutions of the raw materials of the product of the present invention, addition of auxiliary components, selection of specific modes, etc., are within the scope and disclosure of the present invention.