阅读说明：本技术 一种化合物及其应用 (Compound and application thereof ) 是由 张维宏 黄金华 曾礼昌 于 2020-06-30 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I所示的结构,在萘环上取代Ar～(2)基团以及2-位芳胺基团,同时在芳胺基团的N上引入特定的稠环基团,当该化合物应用于有机电致发光器件时,能够提高器件的发光效率、降低驱动电压以及延长使用寿命。另外,本发明化合物的制备工艺简单易行,原料易得,适合于量产放大。(The invention relates to a compound and application thereof, wherein the compound has a structure shown in formula I, and Ar is substituted on a naphthalene ring 2 The compound is used in organic electroluminescent device to raise the luminous efficiency of the device, lower the driving voltage and prolong the service life. In addition, the present inventionThe preparation process of the compound is simple and easy to implement, the raw materials are easy to obtain, and the method is suitable for mass production and amplification.)

1. A compound having a structure according to formula I;

in the formula I, R is¹、R²And R³Each independently selected from hydrogen, halogen, C1-C20 chain alkyl, C1-C12 alkoxy, C3-C20 cycloalkyl, C2-C12 alkenyl, C2-C12 alkynyl, C1-C20 alkylcarbonyl, carboxyl, cyano, substituted or unsubstitutedAny one of C6-C60 aryl, substituted or unsubstituted C3-C60 heteroaryl;

in the formula I, L is¹And L²Each independently selected from any one of a single bond, a substituted or unsubstituted C6-C60 arylene, a substituted or unsubstituted C3-C60 heteroarylene;

in the formula I, Ar is¹And Ar²Each independently selected from any one of substituted or unsubstituted C6-C60 aryl, substituted or unsubstituted C3-C60 heteroaryl;

R¹、R²、R³、L¹、L²、Ar¹and Ar²Wherein, the substituted groups are respectively and independently selected from any one or at least two combinations of halogen, C1-C10 chain alkyl, C3-C10 cycloalkyl, C2-C10 alkenyl, C1-C10 alkoxy, C1-C10 thioalkoxy, C1-C20 alkylcarbonyl, carboxyl, cyano, amino, C6-C30 arylamino, C3-C30 heteroarylamino, C6-C30 aryl or C3-C30 heteroaryl.

2. The compound of claim 1, wherein Ar is Ar²Any one selected from substituted or unsubstituted C6-C30 aryl, substituted or unsubstituted C3-C30 heteroaryl, preferably any one of the following substituted or unsubstituted groups:

wherein the wavy line indicates the bond of the group.

3. The compound of claim 1, wherein the compound has a structure represented by formula II;

in the formula II, R is⁴Selected from hydrogen, halogen, C1-CAny one of a 10-chain alkyl group, a C3-C10 cycloalkyl group, a C1-C10 alkoxy group, a C1-C10 thioalkoxy group, a C6-C30 arylamino group, a C3-C30 heteroarylamino group, a C6-C30 aryl group or a C3-C30 heteroaryl group;

in the formula II, R is¹、R²、R³、L¹、L²And Ar¹All having the same limitations as in formula I.

4. The compound of claim 3, wherein the compound has a structure according to formula III;

in the formula III, R is¹、R²、R³、R⁴、L¹、L²And Ar¹All having the same limitations as in formula II.

5. A compound according to any one of claims 1 to 4 wherein R is¹、R²And R³Are all hydrogen.

6. A compound according to claim 3 or 4, wherein R is⁴Is hydrogen.

7. A compound according to any one of claims 1 to 4, wherein-L is¹-Ar¹Any one selected from substituted or unsubstituted C6-C30 aryl, substituted or unsubstituted C3-C30 heteroaryl, preferably any one of the following substituted or unsubstituted groups:

wherein the wavy line indicates the bond of the group;

preferably, -L¹-Ar¹Wherein the substituted group is selected from any one or at least two combinations of C1-C10 chain alkyl, C3-C10 cycloalkyl or C6-C30 aryl, preferably any one or at least two combinations of methyl, tert-butyl, cyclohexyl, phenyl or naphthyl.

8. A compound according to any one of claims 1 to 4, wherein L is as defined in formula I²Any one selected from a single bond, a substituted or unsubstituted C6-C30 arylene group, and a substituted or unsubstituted C3-C30 heteroarylene group, preferably a single bond or a substituted or unsubstituted C6-C30 arylene group, more preferably a single bond or a substituted or unsubstituted phenylene group, and still more preferably a single bond.

9. The compound of claim 1, wherein the compound has any one of the following structures P1-P218:

10. use of a compound according to any one of claims 1 to 9 in an organic electroluminescent device;

preferably, the compound is used as an electron blocking layer material in the organic electroluminescent device.

11. An organic electroluminescent device comprising a first electrode, a second electrode and at least one organic layer interposed between the first electrode and the second electrode, the organic layer containing at least one compound according to any one of claims 1 to 9;

preferably, the organic layer comprises an electron blocking layer comprising at least one 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, optoelectronic devices based on organic materials have become increasingly popular. The inherent flexibility of organic materials makes them well suited for fabrication on flexible substrates, allowing for the design and production of aesthetically pleasing and crunchy optoelectronic products, with unparalleled advantages over inorganic materials. Examples of such organic optoelectronic devices include Organic Light Emitting Diodes (OLEDs), organic field effect transistors, organic photovoltaic cells, organic sensors, and the like. Among them, OLEDs have been developed particularly rapidly, and have been commercially successful in the field of information display. The OLED can provide three colors of red, green and blue with high saturation, and a full-color display device manufactured by using the OLED does not need an additional backlight source and has the advantages of colorful, light, thin and soft color and the like.

The core of the OLED device is a thin film structure containing various organic functional materials. Common functionalized organic materials are: hole injection materials, hole transport materials, hole blocking materials, electron injection materials, electron transport materials, electron blocking materials, and light emitting host materials and light emitting objects (dyes), and the like. When electricity is applied, electrons and holes are injected, transported to the light emitting region, and recombined therein, respectively, thereby generating excitons and emitting light.

People have developed various organic materials, and the organic materials are combined with various peculiar device structures, so that the carrier mobility can be improved, the carrier balance can be regulated and controlled, the electroluminescent efficiency can be broken through, and the attenuation of the device can be delayed. For quantum mechanical reasons, common fluorescent emitters mainly utilize singlet excitons generated when electrons and holes are combined to emit light, and are still widely applied to various OLED products. Some metal complexes, such as iridium complexes, can emit light using both triplet excitons and singlet excitons, which are called phosphorescent emitters, and the energy conversion efficiency can be increased by up to four times as compared with conventional fluorescent emitters. The thermal excitation delayed fluorescence (TADF) technology can still effectively utilize triplet excitons to achieve higher luminous efficiency without using a metal complex by promoting the conversion of triplet excitons to singlet excitons. Thermal excitation sensitized fluorescence (TASF) technology also achieves higher luminous efficiency by sensitizing the emitter by energy transfer using TADF-like materials.

As OLED products gradually enter the market, there are increasingly higher requirements on the performance of such products. The currently used OLED materials and device structures cannot completely solve the problems of OLED product efficiency, service life, cost and the like.

Disclosure of Invention

It is an object of the present invention to provide a compound that can improve and balance the mobility of holes in an OLED device, reduce the voltage of the device, improve current efficiency, and prolong the lifetime.

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 I;

in the formula I, R is¹、R²And R³Each independently selected from any one of hydrogen, halogen, C1-C20 chain alkyl, C1-C12 alkoxy, C3-C20 cycloalkyl, C2-C12 alkenyl, C2-C12 alkynyl, C1-C20 alkylcarbonyl, carboxyl, cyano, substituted or unsubstituted C6-C60 aryl and substituted or unsubstituted C3-C60 heteroaryl;

in the formula I, L is¹And L²Each independently selected from any one of a single bond, a substituted or unsubstituted C6-C60 arylene, a substituted or unsubstituted C3-C60 heteroarylene;

in the formula I, Ar is¹And Ar²Each independently selected from any one of substituted or unsubstituted C6-C60 aryl, substituted or unsubstituted C3-C60 heteroaryl;

R¹、R²、R³、L¹、L²、Ar¹and Ar²Wherein, the substituted groups are respectively and independently selected from any one or at least two combinations of halogen, C1-C10 chain alkyl, C3-C10 cycloalkyl, C2-C10 alkenyl, C1-C10 alkoxy, C1-C10 thioalkoxy, C1-C20 alkylcarbonyl, carboxyl, cyano, amino, C6-C30 arylamino, C3-C30 heteroarylamino, C6-C30 aryl or C3-C30 heteroaryl.

The above "substituted or unsubstituted" group may be substituted with one substituent, or may be substituted with a plurality of substituents, and when a plurality of substituents are present, different substituents may be selected from different substituents.

In the present invention, the expression of chemical elements includes the concept of chemically identical isotopes, for example, hydrogen (H) includes¹H (protium, or written as H),²H (deuterium, or denoted as D), etc.; carbon (C) then comprises¹²C、¹³C and the like.

In the present invention, the heteroatom of heteroaryl is generally referred to as N, O, S.

In the present invention, the expression "-" denotes a loop structure, and indicates that the linking site is located at an arbitrary position on the loop structure where the linking site can be bonded.

In the present invention, the C6-C60 aryl group includes C6-C60 monocyclic aryl group or C10-C60 fused ring aryl group, wherein monocyclic aryl group means that the aromatic ring exists as a single ring, without fusion, including but not limited to phenyl, biphenyl, or terphenyl group; a fused ring aryl refers to a structure in which at least two aromatic rings are fused, including, but not limited to, naphthyl, anthryl, phenanthryl, fluorenyl, and the like.

In the present invention, the heteroaryl group of C3-C60 includes a monocyclic heteroaryl group of C3-C60 or a fused-ring heteroaryl group of C6-C30, wherein the monocyclic heteroaryl group means that the heteroaryl ring exists in the form of a single ring without fusion, including but not limited to pyridine, pyrimidine, triazine, or a group formed by connecting at least two thereof, etc.; fused heteroaryl refers to a fused ring aryl group containing a heteroatom, including but not limited to a dibenzofuran group, a dibenzothiophene group, or a carbazole group, and the like.

The C1-C20 chain alkyl group is preferably a C1-C10 chain alkyl group, more preferably a C1-C6 chain alkyl group, and examples thereof include: methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, tert-butyl, n-hexyl, n-octyl, n-pentyl, n-heptyl, n-nonyl, n-decyl and the like.

The above-mentioned C3-C20 cycloalkyl group is preferably cyclopropyl, cyclobutyl, cyclopentyl or cyclohexyl.

The above-mentioned C1-C12 alkoxy group is preferably methoxy; the above-mentioned C2-C12 alkenyl group is preferably vinyl; the above-mentioned C2-C12 alkynyl group is preferably ethynyl; the above-mentioned C1-C20 alkylcarbonyl group means R-CO-, wherein R represents C1-C20 alkyl.

The substituted or unsubstituted C6-C60 aryl group, preferably C6-C30 aryl group, is preferably selected from phenyl, biphenyl, terphenyl, naphthyl, anthryl, phenanthryl, indenyl, fluorenyl and derivatives thereof, fluoranthryl, triphenylene, pyrenyl, perylenyl, perylene, and the like,A group of the group consisting of a phenyl group and a tetracenyl group. 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 the group consisting of 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 the group consisting of 9, 9-dimethylfluorene, 9-spirobifluorene and benzofluorene; the pyrenyl group is selected from the group consisting of 1-pyrenyl, 2-pyrenyl and 4-pyrenyl; the tetracene group is selected from the group consisting of 1-tetracene, 2-tetracene, and 9-tetracene.

The substituted or unsubstituted C3-C60 heteroaryl group, preferably C3-C30 heteroaryl group, preferably the heteroaryl group is furyl, thienyl, pyrrolyl, benzofuryl, benzothienyl, isobenzofuryl, indolyl, dibenzofuryl, dibenzothienyl, carbazolyl and derivatives thereof, wherein the carbazolyl derivative is preferably 9-phenylcarbazole, 9-naphthylcarbazole benzocarbazole, dibenzocarbazole, or indolocarbazole.

In the present invention, the numbers for the substitution sites on the naphthalene ring are as follows:

the invention provides a novel organic electroluminescent material, wherein Ar is substituted on naphthalene ring²Radical (I)And 2-arylamine groups, and introduced on NThe group can regulate and control the mobility of molecules, so that when the group is applied to an organic electronic light-emitting device, the light-emitting efficiency can be improved, the driving voltage can be reduced, and the service life can be prolonged.

Preferably, Ar is²Any one selected from substituted or unsubstituted C6-C30 aryl, substituted or unsubstituted C3-C30 heteroaryl, preferably any one of the following substituted or unsubstituted groups:

wherein the wavy line indicates the bond of the group.

Preferably, the compound has the structure shown in formula II;

in the formula II, R is⁴Any one selected from hydrogen, halogen, C1-C10 chain alkyl, C3-C10 cycloalkyl, C1-C10 alkoxy, C1-C10 thioalkoxy, C6-C30 arylamino, C3-C30 heteroarylamino, C6-C30 aryl or C3-C30 heteroaryl;

in the formula II, R is¹、R²、R³、L¹、L²And Ar¹All having the same selection ranges as in formula I.

Preferred substituents Ar on the naphthalene ring in the present invention²Selected from the group consisting of naphthyl, constituting a binaphthyl structure, andthe matching can effectively reduce the energy barrier of hole injection and improve the hole transmission capability, thereby further improving the luminous efficiency of the device, reducing the driving voltage and prolonging the service life.

Preferably, the compound has the structure shown in formula III;

in the formula III, R is¹、R²、R³、R⁴、L¹、L²And Ar¹All having the same selection range as in formula II.

Further, it is preferred in the present invention that naphthyl is substituted at the 1-position of the naphthalene ring, and at the same time, that substitution at the 2-position is linked to naphthylThe structure has good mobility and strong thermal stability, thereby further improving the performance of the device.

Preferably, said R is¹、R²And R³Are all hydrogen.

Preferably, said R is⁴Is hydrogen.

Preferably, said-L¹-Ar¹Any one selected from substituted or unsubstituted C6-C30 aryl, substituted or unsubstituted C3-C30 heteroaryl, preferably any one of the following substituted or unsubstituted groups:

wherein the wavy line indicates the bond of the group.

Preferably, -L¹-Ar¹Wherein the substituted group is selected from any one or at least two combinations of C1-C10 chain alkyl, C3-C10 cycloalkyl or C6-C30 aryl, preferably any one or at least two combinations of methyl, tert-butyl, cyclohexyl, phenyl or naphthyl.

Preferably, in formula I, L is²Any one selected from single bond, substituted or unsubstituted C6-C30 arylene and substituted or unsubstituted C3-C30 heteroarylene, preferably single bondOr a substituted or unsubstituted C6-C30 arylene group, more preferably a single bond or a substituted or unsubstituted phenylene group, and still more preferably a single bond.

Preferably, the compound has any one of the following structures shown as P1 to P218:

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 compound is used as an electron blocking layer material in the organic electroluminescent device.

It is a further object of the present invention to provide an organic electroluminescent device comprising a first electrode, a second electrode and at least one organic layer interposed between the first electrode and the second electrode, the organic layer containing at least one compound according to one of the objects.

Preferably, the organic layer comprises an electron blocking layer containing at least one compound according to one of the objects.

The OLED includes first and second electrodes, and an organic material layer between the electrodes. The organic material may in turn be divided into a plurality of regions. For example, the organic material layer may include a hole transport region, a light emitting layer, and an electron transport region.

In a specific 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 formed by sputtering or depositing a material used as the first electrode on the substrate. 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 material layer may be formed on the electrode by vacuum thermal evaporation, spin coating, printing, or the like. The compound used as the organic material layer may be an organic small molecule, an organic large molecule, and a polymer, and a combination thereof.

The hole transport region is located between the anode and the light emitting layer. The hole transport region may be a Hole Transport Layer (HTL) of a single layer structure including a single layer containing only one compound and a single layer containing a plurality of compounds. The hole transport region may have a multi-layer structure including at least one of a Hole Injection Layer (HIL), a Hole Transport Layer (HTL), and an Electron Blocking Layer (EBL) using the compound of formula I according to the present invention.

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 including compounds shown below as HT-1 to HT-51; 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-51 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-51 may also be used to dope one or more of the compounds HI-1 to HI-3 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 a fluorescent electroluminescence technique. The luminescent layer fluorescent host material may be selected from, but not limited to, the combination of one or more of BFH-1 through BFH-17 listed below.

In one aspect of the invention, the light-emitting layer employs a fluorescent electroluminescence technique. The luminescent layer fluorescent dopant may be selected from, but is not limited to, the combination of one or more of BFD-1 through BFD-24 listed below.

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 PH-1 to PH-85.

In one aspect of the invention, the light-emitting layer employs phosphorescent electroluminescent technology. The phosphorescent dopant of the light emitting layer can be selected from, but is not limited to, one or more of GPD-1 to GPD-47 listed below.

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.

In one aspect of the invention, the light-emitting layer employs phosphorescent electroluminescent technology. The phosphorescent dopant of the light-emitting layer can be selected from, but is not limited to, one or more of YPD-1 to YPD-11 listed below.

In one aspect of the invention, the light-emitting layer employs a thermally activated delayed fluorescence emission technique. The host material of the light-emitting layer is selected from, but not limited to, one or more of the combinations of PH-1 to PH-85.

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-65 listed below.

In one aspect of the invention, a Hole Blocking Layer (HBL) is located between the electron transport layer and the light emitting layer. The hole blocking layer can adopt, but is not limited to, one or more compounds from ET-1 to ET-65 or one or more compounds from PH-1 to PH-46; mixtures of one or more compounds from ET-1 to ET-65 with one or more compounds from PH-1 to PH-46 may also be used, but are not limited thereto.

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，Mg。

Compared with the prior art, the invention has the following beneficial effects:

the invention provides a novel organic electroluminescent material, wherein Ar is substituted on naphthalene ring²Radicals and arylamine radicals, and introduction on NThe group can regulate and control the mobility of molecules, so that when the group is applied to an organic electronic light-emitting device, the light-emitting efficiency can be improved, the driving voltage can be reduced, and the service life can be prolonged.

When the compound is used as an electron barrier layer material of an organic electroluminescent device, the compound can effectively improve the luminous efficiency, reduce the driving voltage and prolong the service life of the device, and the brightness of the organic electroluminescent device reaches 5000cd/m²The current efficiency is more than or equal to 18.4cd/m²Most of them are as high as 19cd/A and above, even more than 20cd/A, which can be increased by about 15-24% compared with the compounds in the prior art.

In addition, the preparation process of the compound is simple and feasible, the raw materials are easy to obtain, and the compound is suitable for mass production and amplification.

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.

The synthetic route of the compound shown in the formula I is as follows:

in the above synthetic route, R¹、R²、R³、L¹、L²、Ar¹And Ar²All have the same meaning as in formula I.

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

The basic chemical materials of various chemicals used in the present invention, such as toluene, sodium tert-butoxide, etc., are purchased from Shanghai Tantake technology Co., Ltd and Xiong chemical Co., Ltd, and other intermediates are obtained by customization. The mass spectrometer used for determining the following compounds was a ZAB-HS type mass spectrometer measurement (manufactured by Micromass, UK).

Synthesis example 1

Synthesis of compound P1:

a500 mL one-necked flask was charged with 15g (55.69mmol) of Compound P, 17.11g (55.69mmol) of 2-bromotriphenylene, and 0.4g (556.92. mu. mol) of 1,1' -bisdiphenylphosphinoferrocene palladium dichloride (i.e., Pd (dppf) Cl₂) 0.45g (1.1mmol) of 2-dicyclohexylphosphine-2 ',6' -dimethoxybiphenyl (i.e. phosphine), 200mL of toluene (toluene), 16.06g (167.08mmol) of sodium tert-butoxide (NaOBu-t), vacuumizing and changing nitrogen for 3 times, and heating the reaction to 90 ℃ for 12 hours. And stopping the reaction after the reaction is finished. Cooling to room temperature, separating the reaction solution, concentrating the organic phase, and performing silica gel column chromatography to obtain compound PM. Theoretical M/Z value of 495 and measured M/Z value of 496.

In a 500mL single-neck flask, 20g (40.35mmol) of Compound PM, 14.33g (52.46mmol) of 3-bromo-9, 9-dimethyl-benzofluorene, 0.37g (403.54. mu. mol) of tris (dibenzylideneacetone) dipalladium (i.e., Pd) were added₂(dba)₃) 0.33g (807.08umol) 2-dicyclohexylphosphine-2 ',6' -dimethoxybiphenyl, 300mL Toluene (Toluene), 11.63g (121.06mmol) sodium tert-butoxide (NaOBu-t), vacuumizing and changing nitrogen for 3 times, and heating the reaction to 110 ℃ for 10 h. And stopping the reaction after the reaction is finished. Cooling to room temperature, separating the reaction solution, concentrating the organic phase, and performing silica gel column chromatography to obtain compound P1. The theoretical value of M/Z is 687, and the measured value of M/Z is 688.

Synthesis example 2

Synthesis of Compound P3

According to the synthesis method of P1, except that 3-bromo-9, 9-dimethyl-benzofluorene was changed to 4-bromobiphenyl in an equivalent amount, compound P3 was obtained. The theoretical value of M/Z is 647, and the measured value of M/Z is 648.

Synthesis example 3

Synthesis of Compound P8

Compound P8 was obtained according to the procedure for the synthesis of P1 except that 3-bromo-9, 9-dimethyl-benzofluorene was replaced with an equivalent amount of 1-bromo-4-tert-butylbenzene. The theoretical value of M/Z is 627, and the measured value of M/Z is 628.

Synthesis example 4

Synthesis of Compound P80

According to the synthesis method of P1, the raw material P is replaced by PA with equal mass; the 3-bromo-9, 9-dimethyl-benzofluorene was exchanged for an equivalent mass of 9-bromophenanthrene to give compound P80. 671 is the theoretical value of M/Z, 672 is the measured value of M/Z.

Synthesis example 5

Synthesis of Compound P82

According to the synthesis method of P1, raw material P is replaced by PE with equal mass; compound P82 was obtained by substituting 3-bromo-9, 9-dimethyl-benzofluorene with an equivalent amount of bromobenzene. The theoretical value of M/Z is 637, and the actual value of M/Z is 638.

Synthesis example 6

Synthesis of Compound P156

According to the synthesis method of P1, the raw material P is replaced by PC with equal mass; compound P156 was obtained by replacing 3-bromo-9, 9-dimethyl-benzofluorene with an equivalent amount of 1- (4-bromophenyl) naphthalene. The theoretical value of M/Z is 753, and the measured value of M/Z is 754.

Synthesis example 7

Synthesis of Compound P175

According to the synthesis method of P1, the raw material P is replaced by PN with equal mass; compound P175 was obtained by substituting 3-bromo-9, 9-dimethyl-benzofluorene for an equivalent amount of 3-bromobenzothiophene. M/Z theoretical value 717, and M/Z measured value 718.

Example 1

This example provides an organic electroluminescent device, which is prepared as follows:

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

placing the glass substrate with the anode in a vacuum chamber, and vacuumizing to less than 1 × 10^-5Pa, vacuum vapor deposition on the anode layer filmHI-3 is used as a hole injection layer, the evaporation rate is 0.1nm/s, and the thickness of the evaporation film is 10 nm;

evaporating HT-4 on the hole injection layer in vacuum to serve as a hole transport layer of the device, wherein the evaporation rate is 0.1nm/s, and the total film thickness of the evaporation is 60 nm;

on the hole transport layer, compound P1 is evaporated in vacuum to be used as an electron blocking layer of the device, the evaporation rate is 0.1nm/s, and the total film thickness of the evaporation is 60 nm;

a luminescent layer of the device is evaporated on the electron blocking layer in vacuum, the luminescent layer comprises a main material and a dye material, the evaporation rate of the main material PH-54 is adjusted to be 0.1nm/s, the evaporation rate of the dye RPD-8 is set in a proportion of 3%, and the total film thickness of evaporation is 40nm by using a multi-source co-evaporation method;

and (3) carrying out vacuum evaporation on an electron transport layer of the device on the light-emitting layer, adjusting the ratio of the material ET-46: ET-57(50/50, w/w), evaporation rate of 0.1nm/s, total film thickness of 25 nm;

LiF with the thickness of 0.5nm is vacuum-evaporated on the Electron Transport Layer (ETL) to be used as an electron injection layer, and an Al layer with the thickness of 150nm is used as a cathode of the device.

Examples 2 to 13, comparative examples 1 to 4 and example 1 differ only in that the electron blocking material P1 was replaced with the compound shown in table 1.

The structures of the electron barrier materials in comparative examples 1 to 4 are as follows:

among them, the compound C-1 is described in detail in patent application JP2008174647A, the compound C-2 is described in detail in patent application CN10511151A, the compound C-3 is described in patent application CN10511151A, and the compound C-4 is described in patent application CN 109749735A.

And (3) performance testing:

the organic electroluminescent device prepared by the above process was subjected to the following performance measurement:

the organic electroluminescence materials prepared in examples and comparative examples were measured at the same brightness using a digital source meter and a luminance meterThe current efficiency of the device. 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 5000cd/m²Then, the ratio of the brightness to the current density is measured to obtain the current efficiency.

The results of the above performance tests are shown in table 1.

TABLE 1

The results show that the novel organic material is used for the organic electroluminescent device, improves the current efficiency, is an electronic barrier material with good performance, and has the required brightness of 5000cd/m²Under the condition that the current efficiency is more than or equal to 18.4cd/m²Most of them are as high as 19cd/A and above, even 20cd/A and above.

P217 of example 8 differs from C-1 of comparative example 1 only in that the substituent on N is different and P217 is substituted withThe data show that it is effective in improving device performance compared to C-1, where the luminous efficiency is improved by 24%.

P3 of example 2 and C-2 of comparative example 2 differ only in the difference of the substituents on N, P3 being substituted withThe data show that it is effective in improving device performance compared to C-2, where the luminous efficiency is improved by 15%.

The difference between P218 of example 9 and C-3 of the comparative example is only that the naphthalene ring of P218 is substituted with a naphthalene group and the naphthalene ring of C-3 has no substituent, and the data shows that the double naphthalene structure can effectively improve the device performance, in which the luminous efficiency is improved by 15%, compared to C-3.

Comparative example 4 the compound C-4 used differs from the compound of the present invention in that the arylamine group is substituted at the 1-position of the naphthalene ring, and the device effect is significantly worse than that of the example.

The above results demonstrate that, in the present invention, in order to further improve the device performance,and Ar²In the absence, and the arylamine must be substituted at the 2-position of the naphthalene ring.

The difference between P36 of example 10 and P156 of example 6 is only that the substituents on the naphthalene ring are different, with naphthyl on P36 and dibenzothiophene group on P156, and the data show that the naphthyl substituted compound P36 can bring better device performance than P156, thus demonstrating the double naphthalene structure and the P156And the matching is more beneficial to improving the performance of the device.

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.