阅读说明：本技术 一种化合物及其应用 (Compound and application thereof ) 是由 高文正 黄金华 张维宏 曾礼昌 于 2020-05-09 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,在本发明的化合物结构中,母核三芳胺基团能够有效调控分子的立体结构,提高分子的堆积致密度,同时萘环1-位引入取代基Ar不仅能够调节邻位位阻大小,还能有效调控分子的扭曲度以降低分子结晶性。特定连接方式的三联苯取代基的引入,能够有效提升材料的折射率,当将本发明的化合物用作有机电致发光器件中,特别是作为电子阻挡层材料时,可以有效提高器件电流效率达到最佳的效果。(The invention relates to a compound and application thereof, wherein the compound has a structure shown in a formula I, in the structure of the compound, a mother nucleus triarylamine group can effectively regulate and control the three-dimensional structure of molecules, the stacking density of the molecules is improved, and meanwhile, a substituent Ar introduced into a 1-position of a naphthalene ring can not only regulate the steric hindrance of an adjacent position, but also effectively regulate and control the twist degree of the molecules so as to reduce the crystallinity of the molecules. The introduction of terphenyl substituent group with a specific connection mode can effectively improve the refractive index of the material, and the invention is realizedThe compound can be used in organic electroluminescent devices, particularly as an electron barrier material, and can effectively improve the current efficiency of the devices to achieve the best effect.)

1. A compound of the general formula has a structure shown in formula I;

in the formula I, Ar is selected from C6-C60 aryl or substituted or unsubstituted C3-C60 heteroaryl;

in the formula I, X is selected from O, S, C (CH)₃)₂Any one of (a);

in the formula I, R is¹Represents one of a single substituent to the maximum permissible substituent, and is independently selected from hydrogen, deuterium, halogen, cyano, nitro, alkenyl, alkynyl, carboxyl, substituted or unsubstituted C1-C20 chain alkyl, substituted or unsubstituted C3-C20 cycloalkyl, substituted or unsubstituted C1-C20 alkoxy, substituted or unsubstituted C6-C60 aryl, and substituted or unsubstituted C3-C60 heteroaryl, and when R is¹When there are plural, adjacent R¹May be fused;

when the substituent group exists in the groups, the substituent group is selected from one or a combination of at least two of halogen, cyano, carbonyl, chain alkyl of C1-C12, cycloalkyl of C3-C12, alkenyl of C2-C10, alkoxy or thioalkoxy of C1-C10, arylamino of C6-C30, heteroarylamino of C3-C30, 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 is selected from O or C (CH)₃)₂。

3. The compound of claim 1, having any one of the structures shown in formulas ii and iii below:

in the formulae II and III, Ar and R¹Are as defined in formula I.

4. A compound according to any one of claims 1 to 3, Ar is selected from substituted or unsubstituted C6-C20 aryl or substituted or unsubstituted C3-C20 heteroaryl;

preferably, Ar is selected from any one of the following substituted or unsubstituted groups:

wherein, the wavy lineIndicates the site of attachment,

when the substituent group exists in the groups, the substituent group is selected from one or a combination of at least two of halogen, cyano, carbonyl, chain alkyl of C1-C12, cycloalkyl of C3-C12, alkenyl of C2-C10, alkoxy or thioalkoxy of C1-C10, arylamino of C6-C30, heteroarylamino of C3-C30, monocyclic aryl or condensed ring aryl of C6-C30, monocyclic heteroaryl or condensed ring heteroaryl of C3-C30.

5. A compound according to any one of claims 1 to 3, wherein Ar is selected from any one of the following substituted or unsubstituted groups:

wherein, the wavy lineIndicates the site of attachment,

when the substituent group exists in the groups, the substituent group is selected from one or a combination of at least two of halogen, cyano, carbonyl, chain alkyl of C1-C12, cycloalkyl of C3-C12, alkenyl of C2-C10, alkoxy or thioalkoxy of C1-C10, arylamino of C6-C30, heteroarylamino of C3-C30, monocyclic aryl or condensed ring aryl of C6-C30, monocyclic heteroaryl or condensed ring heteroaryl of C3-C30.

6. The compound of claim 1, having the structure shown below:

7. use of a compound according to any one of claims 1 to 6 as a functional material in an organic electronic device comprising an organic electroluminescent device, an optical sensor, a solar cell, a lighting element, an organic thin film transistor, an organic field effect transistor, an organic thin film solar cell, an information label, an electronic artificial skin sheet, a sheet-type scanner or electronic paper;

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

8. An organic electroluminescent device comprising a first electrode, a second electrode and one or more light-emitting functional layers interposed between the first electrode and the second electrode, wherein the light-emitting functional layers contain the compound according to any one of claims 1 to 6;

preferably, the light-emitting functional layer comprises an electron blocking layer and at least one of a hole injection layer, a hole transport layer, a light-emitting layer and an electron transport layer, and the electron blocking layer contains the compound according to any one of claims 1 to 6.

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. Examples of such organic optoelectronic devices include Organic Light Emitting Diodes (OLEDs), organic field effect transistors, organic photovoltaic cells, organic sensors, 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.

Therefore, there is a need in the art to develop an organic electroluminescent material that can improve the light emitting efficiency of the device, reduce the driving voltage, and prolong the lifetime.

Disclosure of Invention

The invention aims to provide a compound which is applied to an organic electroluminescent device and can effectively reduce driving voltage and improve the luminous efficiency of the 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 I;

in the formula I, Ar is selected from substituted or unsubstituted C6-C60 aryl or substituted or unsubstituted C3-C60 heteroaryl; ar is preferably one of substituted or unsubstituted aryl of C6-C20 and substituted or unsubstituted heteroaryl of C3-C20;

in the formula I, X is selected from O, S, C (CH)₃)₂Any one of (a); x is preferably O or C (CH)₃)₂Any one of the above;

in the formula I, R is¹Represents one of a single substituent to the maximum permissible substituent, and is independently selected from hydrogen, deuterium, halogen, cyano, nitro, alkenyl, alkynyl, carboxyl, substituted or unsubstituted C1-C20 chain alkyl, substituted or unsubstituted C3-C20 cycloalkyl, substituted or unsubstituted C1-C20 alkoxy, substituted or unsubstituted C6-C60 aryl, and substituted or unsubstituted C3-C60 heteroaryl, and when R is¹When there are plural, adjacent R¹May be fused;

when the substituent group exists in the groups, the substituent group is selected from one or a combination of at least two of halogen, cyano, carbonyl, chain alkyl of C1-C12, cycloalkyl of C3-C12, alkenyl of C2-C10, alkoxy or thioalkoxy of C1-C10, arylamino of C6-C30, heteroarylamino of C3-C30, monocyclic aryl or condensed ring aryl of C6-C30, monocyclic heteroaryl or condensed ring heteroaryl of C3-C30.

Further, the compound of the invention has a structure shown in the following formula II or formula III:

in the formulae II and III, Ar and R¹Are as defined in formula I.

Further preferably, in the above formulae i, ii and iii, Ar is selected from any one of the following substituted or unsubstituted groups:

still more preferably, Ar is selected from any one of the following substituted or unsubstituted groups:

wherein, the wavy lineIndicates the site of attachment,

when the substituent group exists in the groups, the substituent group is selected from one or a combination of at least two of halogen, cyano, carbonyl, chain alkyl of C1-C12, cycloalkyl of C3-C12, alkenyl of C2-C10, alkoxy or thioalkoxy of C1-C10, arylamino of C6-C30, heteroarylamino of C3-C30, monocyclic aryl or condensed ring aryl of C6-C30, monocyclic heteroaryl or condensed ring heteroaryl of C3-C30.

Still more preferably, R is as defined above¹Selected from hydrogen, deuterium or the following substituents: methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, sec-butyl, tert-butyl, 2-methylbutyl, n-pentyl, sec-pentyl, cyclopentyl, neopentyl, n-hexyl, cyclohexyl, neohexylA group, an n-heptyl group, a cycloheptyl group, an n-octyl group, a cyclooctyl group, a 2-ethylhexyl group, a trifluoromethyl group, a pentafluoroethyl group, a 2,2, 2-trifluoroethyl group, a phenyl group, a naphthyl group, an anthracenyl group, a benzanthracenyl group, a phenanthrenyl group, a benzophenanthrenyl group, a pyrenyl group, a cavernyl group, a perylenyl group, a fluoranthenyl group, a tetracenyl group, a pentacenyl group, a benzopyrenyl group, a biphenyl group, an idophenyl group, a terphenyl group, a fluorenyl group, a spirobifluorenyl group, a dihydrophenanthrenyl group, a dihydropyrenyl group, a cis-or trans-indenofluorenyl group, a trimeric indenyl group, an isotridecyl group, a spirotrimeric indenyl group, a spiroisotridecyl group, a furyl group, a benzofuryl group, an isobenzofuryl group, a dibenzofuryl group, a thienyl group, a benzothienyl group, a pyrrolyl group, an isoindolyl group, a carbazolyl group, a pyridyl group, a quinolyl group, an isoquinolyl group, a, Acridinyl, phenanthridinyl, benzo-5, 6-quinolyl, benzo-6, 7-quinolyl, benzo-7, 8-quinolyl, pyrazolyl, indazolyl, imidazolyl, benzimidazolyl, naphthoimidazolyl, phenanthroimidazolyl, pyridoimidazolyl, pyrazinoimidazolyl, quinoxalimidazolyl, oxazolyl, benzoxazolyl, naphthooxazolyl, anthraoxazolyl, phenanthroxazolyl, 1, 2-thiazolyl, 1, 3-thiazolyl, benzothiazolyl, pyridazinyl, benzopyrazinyl, pyrimidinyl, benzopyrimidinyl, quinoxalinyl, 1, 5-diazoanthrenyl, 2, 7-diazpyrenyl, 2, 3-diazpyrenyl, 1, 6-diazpyrenyl, 1, 8-diazpyrenyl, 4, 5-diazenyl, 4,5,9, 10-tetraazaperylene, pyrazinyl, phenazinyl, phenothiazinyl, naphthyridinyl, azacarbazolyl, benzocarbazinyl, phenanthrolinyl, 1,2, 3-triazolyl, 1,2, 4-triazolyl, benzotriazolyl, 1,2, 3-oxadiazolyl, 1,2, 4-oxadiazolyl, 1,2, 5-oxadiazolyl, 1,2, 3-thiadiazolyl, 1,2, 4-thiadiazolyl, 1,2, 5-thiadiazolyl, 1,3, 4-thiadiazolyl, 1,3, 5-triazinyl, 1,2, 4-triazinyl, 1,2, 3-triazinyl, tetrazolyl, 1,2,4, 5-tetrazinyl, 1,2,3, 4-tetrazinyl, 1,2,3, 5-tetrazinyl, purinyl, pteridinyl, One of indolizinyl, benzothiadiazolyl, or a combination selected from the two.

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

In the present invention, the monocyclic aryl group means that one or at least two phenyl groups are contained in a molecule, and when the at least two phenyl groups are contained in a molecule, the phenyl groups are independent of each other and are connected by a single bond, such as phenyl, biphenylyl, terphenylyl, and the like, for example; the fused ring aryl group means that at least two benzene rings are contained in the molecule, but the benzene rings are not independent of each other, but common ring sides are fused with each other, and exemplified by naphthyl, anthryl and the like; monocyclic heteroaryl means that the molecule contains at least one heteroaryl group, and when the molecule contains one heteroaryl group and other groups (e.g., aryl, heteroaryl, alkyl, etc.), the heteroaryl and other groups are independent of each other and are linked by a single bond, illustratively pyridine, furan, thiophene, etc.; fused ring heteroaryl refers to a fused ring of at least one phenyl group and at least one heteroaryl group, or, fused ring of at least two heteroaryl rings, illustratively quinoline, isoquinoline, benzofuran, dibenzofuran, benzothiophene, dibenzothiophene, and the like.

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

In the present invention, 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.

In the present invention, the C3-C20 cycloalkyl group is preferably cyclopropyl, cyclobutyl, cyclopentyl or cyclohexyl.

In the present invention, the substituted or unsubstituted C6-C30 aryl group or C6-C30 condensed ring aryl group is preferably C6-C30 aryl group, more preferably C6-C20 aryl group, and preferably the aryl group is a condensed ring aryl group consisting of phenyl group, C30 aryl group, C6-C30 condensed ring aryl group, C6-C30 condensed ring aryl group, C6-C20 condensed ring aryl group, C3978-C30 condensed ring aryl group, C6-C30 condensed ring aryl group, or C6-C20 condensed ring aryl group, or C6-C20 condensed ring aryl group,Biphenyl, terphenyl, naphthyl, anthryl, phenanthryl, indenyl, fluorenyl and derivatives thereof, fluoranthenyl, triphenylenyl, pyrenyl, perylenyl,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.

In the present invention, the substituted or unsubstituted C3-C30 heteroaryl or C3-C30 fused ring heteroaryl is preferably C3-C30 heteroaryl, more preferably C4-C20 heteroaryl, and preferably the heteroaryl is furyl, thienyl, pyrrolyl, benzofuryl, benzothienyl, isobenzofuryl, indolyl, dibenzofuryl, dibenzothienyl, carbazolyl or a derivative thereof, wherein the carbazolyl derivative is preferably 9-phenylcarbazole, 9-naphthylcarbazole benzocarbazole, dibenzocarbazole, or indolocarbazole.

Furthermore, the compounds described by the general formula of the present invention may preferably be compounds of the following specific structures represented by C1-C126, which are merely representative:

the second object of the present invention is to provide the use of the compound according to the first object for the application in organic electronic devices.

Preferably, the organic electronic device includes an organic electroluminescent device, an optical sensor, a solar cell, a lighting element, an organic thin film transistor, an organic field effect transistor, an organic thin film solar cell, an information label, an electronic artificial skin sheet, a sheet type scanner, or electronic paper, preferably 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.

Specifically, another technical scheme of the present invention provides an organic electroluminescent device, including a substrate, and an anode layer, a plurality of light emitting functional layers and a cathode layer sequentially formed on the substrate; the light-emitting functional layer comprises an electron blocking layer and at least one of a hole injection layer, a hole transport layer, a light-emitting layer and an electron transport layer, wherein the electron blocking layer contains at least one of the compounds.

More specifically, the organic electroluminescent device will be described in detail.

The OLED device 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 also be 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); wherein the HIL is located between the anode and the HTL and the EBL is located between the HTL and the light emitting layer.

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), and aromatic amine derivatives as shown below in 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.

Wherein D is deuterium.

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 organic electroluminescent device of the present invention includes 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).

The electron transport region may also be formed using the compound of the present invention for a multilayer structure including at least one of an Electron Injection Layer (EIL), an Electron Transport Layer (ETL), and a Hole Blocking Layer (HBL), although the material of the electron transport region may also be combined with one or more of ET-1 to 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 material including, but not limited to, combinations of one or more of the following:

LiQ、LiF、NaCl、CsF、Li₂O、Cs₂CO₃、BaO、Na、Li、Ca、Mg。

in the present invention, the site markers in formula I are represented by the following formula:

the specific reason why the compound of the present invention has excellent properties is not clear, and it is presumed that the following reasons may be mentioned:

in the compound parent nucleus structure, a substituent Ar is introduced to the 1-position of a naphthalene ring, so that not only can the size of ortho steric hindrance be adjusted, but also the twist degree of molecules can be effectively regulated and controlled to reduce the crystallinity of the molecules, an arylamine group is substituted to the 2-position, and the introduction of a trisubstituted structure on the arylamine group can effectively regulate and control the three-dimensional structure of the molecules, so that the stacking density of the molecules is improved. Meanwhile, a terphenyl substituent group is introduced in a specific connection mode and is matched with a dibenzo heterocyclic group for use, so that the molecular structure of the compound is ensured to be extended in a rod shape, and the refractive index of the material can be effectively improved. The compound is applied to an organic electroluminescent device, and particularly can improve the light extraction efficiency of the organic electroluminescent device when being used as an electron blocking layer, so that the current efficiency of the device is improved and the best effect is achieved.

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 general formula I is as follows:

wherein, X, R₁Ar has the same definition as the symbol in formula I; pd₂(dba)₃Represents tris (dibenzylacetone) dipalladium (0), IPr. HCl represents 1, bis (2, diisopropylphenyl) imidurium chloride, NaOBu-t represents sodium tert-butoxide, (t-Bu)₃P represents tri-tert-butylphosphine.

More specifically, the present invention provides a specific synthesis method of a representative compound as exemplified by the following synthesis examples, and the solvents and reagents used in the following synthesis examples, such as 3-bromo-9, 9-dimethylfluorene, 1, bis (2, diisopropylphenyl) imidazolium chloride, tris (dibenzylacetone) dipalladium (0), toluene, methanol, ethanol, tri-tert-butylphosphine, sodium tert-butoxide, and other chemical reagents, can be purchased or customized from domestic chemical product markets, such as reagents from national drug group, Sigma-Aldrich, and carbofuran, and intermediates M1 to M7, which are customized by reagent companies. In addition, they can be synthesized by a known method by those skilled in the art.

Synthesis example 1: synthesis of Compound C1

15g P1, 17.17g of 4-bromoterphenyl, 0.51g of tris (dibenzylideneacetone) dipalladium, 0.46g of IPr.HCl, 600mL of toluene and 16.40g of sodium tert-butoxide are added into a 1L single-neck flask, the mixture is vacuumized and nitrogen-exchanged for 3 times, and the reaction is heated to 90 ℃ for 6 hours. And stopping the reaction after the reaction is finished. Cooling to room temperature, subjecting the reaction solution to 100-mesh 200-mesh silica gel column chromatography, eluting with toluene, removing solvent, adding methanol, stirring for 1h, vacuum filtering to obtain crude product, boiling with methanol/ethyl acetate for 2h, and filtering to obtain white powder M1.

10g M1, 7.14g of 3-bromo-9, 9-dimethylfluorene, 0.92g of tris (dibenzylideneacetone) dipalladium, 1mL of tri-tert-butylphosphine, 600mL of toluene and 5.79g of sodium tert-butoxide are added into a 1L single-neck flask, the mixture is evacuated and nitrogen is exchanged for 3 times, and the reaction is heated to 110 ℃ for 6 hours. And stopping the reaction after the reaction is finished. Cooling to room temperature, carrying out column chromatography on the reaction solution through a 100-sand 200-mesh silica gel column, eluting the solvent with toluene, adding methanol, stirring for 1h, and carrying out suction filtration to obtain a crude product. Column chromatography separation and purification, eluting with petroleum ether: dichloromethane 10:1, white powder C1 was obtained.

M/Z theoretical value: 689.3, respectively; ZAB-HS type mass spectrometer (manufactured by Micromass, UK) M/Z measured value: 690.3.

synthesis example 2: synthesis of Compound C3

15g P1, 21.41g of 4-bromotetrabiphenyl, 0.51g of tris (dibenzylideneacetone) dipalladium, 0.46g of IPr.HCl, 600mL of toluene and 16.40g of sodium tert-butoxide are added into a 1L single-neck flask, the mixture is vacuumized and nitrogen-exchanged for 3 times, and the reaction is heated to 90 ℃ for 6 hours. And stopping the reaction after the reaction is finished. Cooling to room temperature, subjecting the reaction solution to 100-mesh 200-mesh silica gel column chromatography, eluting with toluene, removing solvent, adding methanol, stirring for 1h, vacuum filtering to obtain crude product, boiling with methanol/ethyl acetate for 2h, and filtering to obtain white powder M2.

13g M2, 8.02g of 3-bromo-9, 9-dimethylfluorene, 1.04g of tris (dibenzylideneacetone) dipalladium, 2mL of tri-tert-butylphosphine, 600mL of toluene and 6.55g of sodium tert-butoxide are added into a 1L single-neck flask, the mixture is vacuumized and nitrogen-exchanged for 3 times, and the reaction is heated to 110 ℃ for 6 hours. And stopping the reaction after the reaction is finished. Cooling to room temperature, carrying out column chromatography on the reaction solution through a 100-sand 200-mesh silica gel column, eluting the solvent with toluene, adding methanol, stirring for 1h, and carrying out suction filtration to obtain a crude product. Column chromatography separation and purification, eluting with petroleum ether: dichloromethane (10:1) gave white powder C3.

M/Z theoretical value: 765.3; ZAB-HS type mass spectrometer (manufactured by Micromass, UK) M/Z measured value: 766.3.

synthesis example 3: synthesis of Compound C19

In a 1L single-neck flask, 15g M1, 9.76g of 2-bromo-dibenzofuran, 1.38g of tris (dibenzylideneacetone) dipalladium, 2mL of tri-tert-butylphosphine, 600mL of toluene, and 8.68g of sodium tert-butoxide are added, and the mixture is evacuated and purged with nitrogen for 3 times, and the reaction is heated to 110 ℃ for 6 hours. And stopping the reaction after the reaction is finished. Cooling to room temperature, carrying out column chromatography on the reaction solution through a 100-sand 200-mesh silica gel column, eluting the solvent with toluene, adding methanol, stirring for 1h, and carrying out suction filtration to obtain a crude product. Column chromatography separation and purification, eluting with petroleum ether: dichloromethane (10:1) gave white powder C19.

M/Z theoretical value: 663.3, respectively; ZAB-HS type mass spectrometer (manufactured by Micromass, UK) M/Z measured value: 664.3.

synthesis example 4: synthesis of Compound C55

15g P2, 15.48g of 4-boric acid-dibenzothiophene, 1.57g of tetratriphenylphosphine palladium, 18.73g of potassium carbonate, 400mL of toluene and 200mL of water are added into a 1L single-neck bottle, vacuum pumping is carried out, nitrogen gas is exchanged for 3 times, and the reaction is heated to reflux for 5 hours. And stopping the reaction after the reaction is finished. Cooling to room temperature, separating the reaction solution, concentrating the organic phase, adding n-hexane, stirring for 1h, filtering to obtain a crude product, and recrystallizing with toluene/ethanol to obtain an intermediate M3.

In a 1L single-neck flask, 18g M3, 17.17g of 4-bromoterphenyl, 0.51g of tris (dibenzylideneacetone) dipalladium, 0.46g of IPr.HCl, 600mL of toluene and 16.40g of sodium tert-butoxide are added, the vacuum is pumped and the nitrogen is exchanged for 3 times, and the reaction is heated to 90 ℃ for 6 h. And stopping the reaction after the reaction is finished. Cooling to room temperature, subjecting the reaction solution to 100-mesh 200-mesh silica gel column chromatography, eluting with toluene, removing solvent, adding methanol, stirring for 1h, vacuum filtering to obtain crude product, boiling with methanol/ethyl acetate for 2h, and filtering to obtain light yellow powder M4.

12g M4, 7.67g of 3-bromo-9, 9-dimethylfluorene, 0.99g of tris (dibenzylideneacetone) dipalladium, 2mL of tri-tert-butylphosphine, 600mL of toluene and 6.25g of sodium tert-butoxide are added into a 1L single-neck flask, the mixture is vacuumized and nitrogen-exchanged for 3 times, and the reaction is heated to 110 ℃ for 6 hours. And stopping the reaction after the reaction is finished. Cooling to room temperature, carrying out column chromatography on the reaction solution through a 100-sand 200-mesh silica gel column, eluting the solvent with toluene, adding methanol, stirring for 1h, and carrying out suction filtration to obtain a crude product. Column chromatography separation and purification, eluting with petroleum ether: dichloromethane (10:1) gave C55 as a pale yellow powder.

M/Z theoretical value: 745.3, respectively; ZAB-HS type mass spectrometer (manufactured by Micromass, UK) M/Z measured value: 746.3.

synthesis example 5: synthesis of Compound C59

In a 1L single-neck flask, 12g M4, 5.34g of 2-bromo-dibenzofuran, 0.99g of tris (dibenzylideneacetone) dipalladium, 2mL of tri-tert-butylphosphine, 600mL of toluene, 6.25g of sodium tert-butoxide, evacuation and nitrogen exchange are carried out for 3 times, and the reaction is heated to 110 ℃ for 6 hours. And stopping the reaction after the reaction is finished. Cooling to room temperature, carrying out column chromatography on the reaction solution through a 100-sand 200-mesh silica gel column, eluting the solvent with toluene, adding methanol, stirring for 1h, and carrying out suction filtration to obtain a crude product. Column chromatography separation and purification, eluting with petroleum ether: dichloromethane (10:1) gave C59 as a pale yellow powder.

M/Z theoretical value: 719.2, respectively; ZAB-HS type mass spectrometer (manufactured by Micromass, UK) M/Z measured value: 720.2.

synthesis example 6: synthesis of Compound C81

15g P2, 14.39g of 3-boronic acid-dibenzofuran, 1.57g of tetratriphenylphosphine palladium, 18.73g of potassium carbonate, 400mL of toluene and 200mL of water are added into a 1L single-neck bottle, vacuum pumping is carried out for 3 times of nitrogen exchange, and the reaction is heated to reflux for 5 hours. And stopping the reaction after the reaction is finished. Cooling to room temperature, separating the reaction solution, concentrating the organic phase, adding n-hexane, stirring for 1h, filtering to obtain a crude product, and recrystallizing with toluene/ethanol to obtain an intermediate M5.

15g M5, 14.95g of 4-bromoterphenyl, 0.44g of tris (dibenzylideneacetone) dipalladium, 0.41g of IPr.HCl, 600mL of toluene and 13.85g of sodium tert-butoxide are added into a 1L single-neck flask, the mixture is vacuumized and nitrogen-exchanged for 3 times, and the reaction is heated to 90 ℃ for 6 hours. And stopping the reaction after the reaction is finished. Cooling to room temperature, subjecting the reaction solution to 100-mesh 200-mesh silica gel column chromatography, eluting with toluene, removing solvent, adding methanol, stirring for 1h, vacuum filtering to obtain crude product, boiling with methanol/ethyl acetate for 2h, and filtering to obtain light yellow powder M6.

12g M6, 7.90g of 2-bromo-9, 9-dimethylfluorene, 1.02g of tris (dibenzylideneacetone) dipalladium, 2mL of tri-tert-butylphosphine, 600mL of toluene and 6.44g of sodium tert-butoxide are added into a 1L single-neck flask, the mixture is vacuumized and nitrogen-exchanged for 3 times, and the reaction is heated to 110 ℃ for 6 hours. And stopping the reaction after the reaction is finished. Cooling to room temperature, carrying out column chromatography on the reaction solution through a 100-sand 200-mesh silica gel column, eluting the solvent with toluene, adding methanol, stirring for 1h, and carrying out suction filtration to obtain a crude product. Column chromatography separation and purification, eluting with petroleum ether: dichloromethane (10:1) gave C81 as a pale yellow powder.

M/Z theoretical value: 729.3, respectively; ZAB-HS type mass spectrometer (manufactured by Micromass, UK) M/Z measured value: 730.3.

synthesis example 7: synthesis of Compound C110

15g P2, 13.44g of 4-biphenylboronic acid, 1.57g of tetratriphenylphosphine palladium, 18.73g of potassium carbonate, 400mL of toluene and 200mL of water are added into a 1L single-neck bottle, vacuum pumping is carried out, nitrogen gas is exchanged for 3 times, and the reaction is heated to reflux for 5 hours. And stopping the reaction after the reaction is finished. Cooling to room temperature, separating the reaction solution, concentrating the organic phase, adding n-hexane, stirring for 1h, filtering to obtain a crude product, and recrystallizing with toluene/ethanol to obtain an intermediate M7.

13g M7, 13.57g of 4-bromoterphenyl, 0.40g of tris (dibenzylideneacetone) dipalladium, 0.37g of IPr.HCl, 600mL of toluene and 12.69g of sodium tert-butoxide are added into a 1L single-neck flask, the mixture is vacuumized and nitrogen-exchanged for 3 times, and the reaction is heated to 90 ℃ for 6 hours. And stopping the reaction after the reaction is finished. Cooling to room temperature, subjecting the reaction solution to 100-mesh 200-mesh silica gel column chromatography, eluting with toluene, removing solvent, adding methanol, stirring for 1h, vacuum filtering to obtain crude product, boiling with methanol/ethyl acetate for 2h, and filtering to obtain white powder M8.

12g M8, 8.79g of 3-bromo-9, 9-dimethylfluorene, 1.05g of tris (dibenzylideneacetone) dipalladium, 2mL of tri-tert-butylphosphine, 600mL of toluene and 6.61g of sodium tert-butoxide are added into a 1L single-neck flask, the mixture is evacuated and nitrogen is exchanged for 3 times, and the reaction is heated to 110 ℃ for 6 hours. And stopping the reaction after the reaction is finished. Cooling to room temperature, carrying out column chromatography on the reaction solution through a 100-sand 200-mesh silica gel column, eluting the solvent with toluene, adding methanol, stirring for 1h, and carrying out suction filtration to obtain a crude product. Column chromatography separation and purification, eluting with petroleum ether: dichloromethane (10:1) gave white powder C110.

M/Z theoretical value: 715.3, respectively; ZAB-HS type mass spectrometer (manufactured by Micromass, UK) M/Z measured value: 716.3.

device example 1

This embodiment 1 provides a method for manufacturing an organic electroluminescent device, which includes the following steps:

the glass plate coated with the ITO transparent conductive layer (as anode) 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;

the glass substrate with the anode is processedPlacing in a vacuum chamber, and vacuumizing to less than 1 × 10^-5Pa, performing vacuum evaporation on the anode layer film to obtain a HT-4: HI-3(97/3, w/w) mixture as a hole injection layer, wherein the evaporation rate is 0.1nm/s, and the evaporation film thickness 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;

and (3) evaporating the compound C1 on the hole transport layer in vacuum to be used as an electron barrier layer material of the device, wherein 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 vacuum evaporated on the electron blocking layer, the luminescent layer comprises a main material and a dye material, the evaporation rate of the main material GPH-59 is adjusted to be 0.1nm/s, the evaporation rate of the dye RPD-8 is 3% of the evaporation rate of the main material, the proportion is set, and the total evaporation film thickness is 40 nm;

vacuum evaporating electron transport layer materials ET-61 and ET-57 of the device on the light emitting layer, wherein the mass ratio of the two materials is 1:1, the evaporation rate is 0.1nm/s, and the total evaporation film thickness is 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.

Device examples 2 to 7 differ from device example 1 only in that the compound C1 according to the invention used in the electron blocking layer was replaced by another compound according to the invention, as specified in table 1.

Device comparative examples 1 to 6 were conducted in the same manner as in example 1 except that the compound C1 of the material of the present invention used in the electron blocking layer was replaced with the compounds R1 to R6 of the prior art, respectively, and the structural formulae of the specific compounds are as follows:

and (3) performance testing:

(1) the driving voltage and current efficiency and the lifetime of the organic electroluminescent devices prepared in examples and comparative examples were measured at the same luminance using a digital source meter (Keithley2400) and a luminance meter (ST-86LA type luminance meter, photoelectric instrument factory of beijing university). 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/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 LT97 is as follows: using a luminance meter at 5000cd/m²At luminance, a constant current was maintained, and the time in hours for which the luminance of the organic electroluminescent device was reduced to 97% was measured.

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

Table 1:

as can be seen from the data in Table 1, under the condition that the material schemes and the preparation processes of other functional layers in the structure of the organic electroluminescent device are completely the same, when the compound provided by the invention is used as an electron blocking layer material of the organic electroluminescent device, the brightness of the device reaches 5000cd/m²When the driving voltage is lower than 4.3V, the current efficiency is higher than 19cd/A, and LT97 is higher than 18h, which are all superior to the comparative example device using the compound in the prior art as the electron barrier material.

Compared with the compound of the invention, the compound R1 adopted in the comparative example 1 is different from the spirofluorene group, so that the molecular rigidity is increased, the sublimation temperature of the material is higher, and the material is not suitable for practical application; meanwhile, due to the increase of the molecular volume, the rod-shaped orientation degree of the material is reduced, the refractive index of the material is reduced, and the transmission capability is reduced; in particular, the refractive index is lower than that of the heteroatom-containing compound of the present invention. When the compound R1 is used as an electron blocking layer material of an organic electroluminescent device, the driving voltage of the device is 4.94V, and the current efficiency is 18.47 cd/A. This can be attributed to the fact that compound R1 has a weak hole transport property and a high driving voltage; and also the refractive index is low, leading to a reduction in light extraction efficiency.

The compound R2 used in comparative example 2 is different from the compound of the present invention in that the coupling mode of the terphenyl substituents is meta-position coupling, the rod-like orientation of the molecules is destroyed, and the refractive index of the material is not as high as that of the compound of the present invention; meanwhile, the transmission performance of the current carrier is reduced by the meta connection mode; when the compound is used as an electron barrier material of an organic electroluminescent device, the driving voltage of the device is 5.12V, the current efficiency is 16.12cd/A, and the voltage and current efficiency are poor, which can be attributed to the fact that the compound R2 molecular configuration causes lower refractive index and the reduction of transmission performance, thereby causing the reduction of photoelectric performance.

Compared with the compounds of the invention, the compounds R3 and R4 adopted in comparative example 3 and comparative example 4 are different in that phenanthrene groups are introduced into the structures of the compounds R3 and R4, the triplet energy level of the material is lower, and annihilation of excited state energy is easily caused. When the compounds R3 and R4 are used as electron blocking layer materials of organic electroluminescent devices, the current efficiency of the devices is lower than that of the devices prepared by adopting the compounds, because the electron blocking layer is adjacent to a light emitting layer and needs to have an exciton blocking function, and because the compounds R3 and R4 have lower triplet state energy levels, after electrons and holes form excitons in the light emitting layer, the excitons are transferred to the electron blocking layer, so that energy annihilation exists, and the efficiency of the devices is reduced.

The compound R5 used in comparative example 5 is different from the compound of the present invention in that biphenyl is used in the structure of the compound R5, so that the orientation of the molecules is weakened and the refractive index of the material is lowered; the refractive index of compound R5 was found to be 1.76, significantly lower than 1.82 of compound C1 of the present invention, at 628 nm. When the compound R5 is used as an electron blocking layer material of an organic electroluminescent device, the current efficiency of the device is lower than the performance of the device prepared by using the compound of the invention, which is caused by the reduction of the refractive index, thereby causing the reduction of the light extraction efficiency.

Compared with the compound disclosed by the invention, the difference of the compound R6 adopted in the comparative example 6 is that naphthalene is adopted in the structure of the compound R6, the hole transport performance of the material is obviously reduced compared with the compound disclosed by the invention, and meanwhile, the compound disclosed by the invention can effectively regulate the twist degree of molecules so as to reduce the crystallinity of the molecules by virtue of substitution at the ortho position. When the compound R6 is used as an electron barrier material of an organic electroluminescent device, the voltage of the device is higher, and the current efficiency of the device is lower than the performance of the device prepared by adopting the compound, which is caused by the reduction of the transmission performance, thereby causing the reduction of the performance of the device.

The experimental data show that the novel organic material is obviously improved compared with the prior art as an electron blocking material of an organic electroluminescent device, is an organic luminescent functional material with good performance, and has wide application prospect.

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.