Alkane substituted compound, hole transport material and organic electroluminescent device

Abstract

The invention relates to the technical field of organic light-emitting display, in particular to an alkane substituted compound, a hole transport material and an organic light-emitting device. The invention provides a compound as shown in a general formula (I), which can be used for hole transport materials. The compound has a parent structure of ortho-substituted arylamine, is high in bond energy among atoms, has good thermal stability, is beneficial to solid-state accumulation among molecules, is high in hole transition capability, and can be used as a hole transport material and a light-emitting auxiliary layer material to effectively reduce the voltage of a device and prolong the service life of the material. The invention also provides an organic electroluminescent device and a display device containing the compound shown in the general formula (I). # imgabs0 #

Description

Technical Field

[0001] The present invention relates to the technical field of organic light-emitting display, and particularly relates to an alkane-substituted compound, a hole transport material, and an organic electroluminescent device. Background Art

[0002] Electroluminescence (EL) refers to the phenomenon that a luminescent material emits light under the action of an electric field, being excited by an electric current and an electric field. It is a luminescence process that directly converts electrical energy into light energy. Organic electroluminescent displays (hereinafter referred to as OLEDs) have a series of advantages such as self-luminescence, low-voltage DC drive, all-solid state, wide viewing angle, light weight, simple composition and process. Compared with liquid crystal displays, organic electroluminescent displays do not require a backlight, have a large viewing angle, low power, a response speed that can reach 1000 times that of liquid crystal displays, and a manufacturing cost lower than that of liquid crystal displays with the same resolution. Therefore, organic electroluminescent devices have very broad application prospects.

[0003] With the continuous advancement of OLED technology in the two major fields of lighting and display, people pay more attention to the research on high-efficiency organic materials that affect the performance of OLED devices. An organic electroluminescent device with high efficiency and long life is usually the result of an optimized combination of the device structure and various organic materials, which provides great opportunities and challenges for the design and development of functional materials with various structures.

[0004] Compared with inorganic luminescent materials, organic electroluminescent materials have many advantages. For example, they have good processability and can form films on any substrate by evaporation or spin coating, enabling flexible display and large-area display; by changing the molecular structure, the optical, electrical, and stability properties of the materials can be adjusted, and there is a large space for material selection. In the most common OLED device structure, it usually includes the following types of organic materials: hole injection materials, hole transport materials, electron transport materials, as well as various color-emitting materials (dyes or doped guest materials) and corresponding host materials, etc. Among them, as an important functional material, the hole transport material has a direct impact on the hole mobility and ultimately affects the light-emitting efficiency of OLEDs. However, the hole migration rate that can be achieved by the hole transport materials currently applied in OLEDs is relatively low, the energy level matching with the adjacent layer is poor, and the efficiency and life cannot be taken into account at the same time, seriously restricting the display function and development of OLED display devices. Summary of the Invention

[0005] The purpose of the present invention is to provide an alkane-substituted compound and a hole transport material to improve the working efficiency and extend the service life of an organic electroluminescent device.

[0006] An object of the first aspect of the present invention is to provide an alkane-substituted compound having a structure represented by formula (I):

[0007]

[0008] Wherein, L 1 and L 2 are each independently selected from a chemical bond, a substituted or unsubstituted C6-C 30 aryl group, a substituted or unsubstituted C5-C 30 heteroaryl group;

[0009] R 1 and R 2 are each independently selected from a C1-C4 alkyl group, a C3-C6 cycloalkane, a substituted or unsubstituted C6-C 30 aryl group, a substituted or unsubstituted C5-C 30 heteroaryl group, and adjacent substituents can be connected to form a ring;

[0010] R and R' are each independently selected from hydrogen, a substituted or unsubstituted C6-C 30 aryl group, a substituted or unsubstituted C5-C 30 heteroaryl group;

[0011] m, n, and o are each independently selected from 0, 1, 2, 3, 4;

[0012] X is selected from O, S, N;

[0013] Ar is selected from a substituted or unsubstituted C6-C 30 aryl group, a substituted or unsubstituted C5-C 30 heteroaryl group;

[0014] A is selected from the following fragments:

[0015]

[0016] The heteroatoms on the heteroaryl group are each independently selected from O, S, or N;

[0017] The hydrogen atoms on the aryl group and heteroaryl group can each independently be substituted by Ra, and Ra are each independently selected from deuterium, halogen, nitro, cyano, a C1-C4 alkyl group, a C5-C 20 cycloalkyl group, phenyl group, biphenyl group, terphenyl group, or naphthyl group.

[0018] Preferably, the Ar is selected from a substituted or unsubstituted C6-C 24 aryl group, a substituted or unsubstituted C5-C 18 heteroaryl group.

[0019] Preferably, the R 1, R 2 Each independently selected from methyl, ethyl, isopropyl, tert-butyl, cyclopentyl, cyclohexyl, and the following groups which are unsubstituted or substituted by Ra: phenyl, biphenyl, naphthyl, fluorenyl, dibenzofuranyl, dibenzothiophenyl, carbazolyl.

[0020] Preferably, the R and R' are each independently selected from hydrogen and the following groups which are unsubstituted or substituted by Ra: phenyl, biphenyl, terphenyl, naphthyl, phenanthryl, triphenylene, fluorenyl, dibenzofuranyl, dibenzothiophenyl, 9,9-dimethylfluorenyl, spirofluorene, arylamine group.

[0021] More preferably, the Ar is selected from the following groups which are unsubstituted or substituted by Ra: phenyl, biphenyl, terphenyl, naphthyl, phenanthryl, triphenylene, fluorenyl, benzofuranyl, dibenzofuranyl, benzothiophenyl, dibenzothiophenyl, 9,9-dimethylfluorenyl, spirofluorene, arylamine group, carbazolyl.

[0022] Preferably, the compound is selected from the compounds shown as A1 - A20:

[0023]

[0024] The object of the second aspect of the present invention is to provide a hole transporting material, which comprises at least one of the compounds provided in the first aspect of the present invention.

[0025] The object of the third aspect of the present invention is to provide an organic electroluminescent device, which comprises at least one of the hole transporting materials provided in the second aspect of the present invention.

[0026] The object of the fourth aspect of the present invention is to provide a display device, which comprises the organic electroluminescent device provided in the third aspect of the present invention.

[0027] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0028] 1. The compounds of the present invention have the parent structure of ortho-substituted arylamine, with high bond energy between atoms, good thermal stability, which is conducive to solid-state stacking between molecules, and strong hole transition ability. When used as a hole transporting layer material, it can effectively reduce the device voltage and improve the lifespan of the material.

[0029] 2. The compounds of the present invention, when applied in the hole transporting layer, have appropriate energy level levels with adjacent layers, which is conducive to hole injection and migration, can effectively reduce the driving voltage. At the same time, with a relatively high hole migration rate, it can achieve good luminous efficiency in the device.

[0030] 3. The compounds of the present invention have a large conjugated plane, which is beneficial to molecular packing, showing good thermodynamic stability and long lifespan in devices.

[0031] Meanwhile, the preparation process of the compounds of the present invention is simple and feasible, and the raw materials are easily available, being suitable for industrial production. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings required in the description of the embodiments or the prior art. Obviously, the drawings in the following description are only one embodiment of the present invention, and those of ordinary skill in the art can also obtain other embodiments based on these drawings.

[0033] Figure 1 It is a schematic structural diagram of a typical organic electroluminescent device. Each part is respectively: 1. Substrate; 2. Reflective anode electrode; 3. Hole injection layer; 4. Hole transport layer; 5. Light-emitting layer; 6. Electron transport layer; 7. Electron injection layer; 8. Cathode electrode. SPECIFIC EMBODIMENTS

[0034] The following will clearly and completely describe the technical solutions in the present invention in conjunction with the drawings. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all of them. All other embodiments obtained by those of ordinary skill in the art based on the embodiments in the present invention fall within the scope of protection of the present invention.

[0035] In the present invention, there are no particular limitations on the types and structures of the organic electroluminescent devices, as long as the hole transport materials provided by the present invention can be used.

[0036] The organic electroluminescent devices of the present invention can be light-emitting devices with a top-emitting structure. For example, they sequentially include an anode, a hole injection layer, a hole transport layer, a light-emitting layer, an electron transport layer, an electron injection layer, and a transparent or semi-transparent cathode on a substrate.

[0037] The organic electroluminescent devices of the present invention can also be light-emitting devices with a bottom-emitting structure. For example, they sequentially include a transparent or semi-transparent anode, a hole injection layer, a hole transport layer, a light-emitting layer, an electron transport layer, an electron injection layer, and a cathode structure on a substrate.

[0038] The organic electroluminescent devices of the present invention can also be light-emitting devices with a double-sided emission structure. For example, they sequentially include a transparent or semi-transparent anode, a hole injection layer, a hole transport layer, a light-emitting layer, an electron transport layer, an electron injection layer, and a transparent or semi-transparent cathode structure on a substrate.

[0039] In the organic electroluminescent device of the present invention, except that the hole transport layer contains the hole transport material provided by the present invention, any material used for the layer in the prior art can be used for other layers.

[0040] Figure 1 FIG. shows a schematic diagram of a typical organic electroluminescent device, in which, from bottom to top, a substrate 1, a reflective anode electrode 2, a hole injection layer 3, a hole transport layer 4, a light-emitting layer 5, an electron transport layer 6, an electron injection layer 7, and a cathode electrode 8 are sequentially arranged.

[0041] It can be understood that Figure 1 only a schematic structure of a typical organic electroluminescent device is shown, and the present invention is not limited to this structure. The hole transport material of the present invention can be used for any type of organic electroluminescent device. For example, the organic electroluminescent device may further include an electron blocking layer, a hole blocking layer, a light extraction layer, etc. In actual applications, these layers can be added or omitted according to specific circumstances.

[0042] For convenience, the organic electroluminescent device of the present invention will be described below with reference to Figure 1 However, this does not mean any limitation to the protection scope of the present invention. It can be understood that all organic electroluminescent devices that can use the hole transport material of the present invention are within the protection scope of the present invention.

[0043] In the present invention, the substrate 1 is not particularly limited, and conventional substrates used in organic electroluminescent devices in the prior art can be used. For example, glass, polymer materials, and glass and polymer materials with TFT components, etc.

[0044] In the present invention, the material of the reflective anode electrode 2 is not particularly limited, and it can be selected from transparent conductive materials known in the prior art such as indium tin oxide (ITO), indium zinc oxide (IZO), tin dioxide (SnO2), zinc oxide (ZnO), low-temperature polycrystalline silicon (LTPS), etc., or metal materials such as silver and its alloys, aluminum and its alloys, etc., or organic conductive materials such as PEDOT (poly-3,4-ethylenedioxythiophene), or a multilayer structure of the above materials, etc.

[0045] In the present invention, the material of the hole injection layer 3 is not particularly limited, and a hole injection material known in the art or the hole transport material provided by the present invention can be selected as the hole injection material.

[0046] For example, the material of the hole injection layer can be selected from at least one of the following compounds HT-1 to HT-31:

[0047]

[0048]

[0049] In the present invention, the hole injection layer 3 may further include a p-type dopant. The type of the p-type dopant is not particularly limited, and various p-type dopants known in the art can be used. For example, the p-type dopant can be selected from at least one of the following compounds:

[0050]

[0051] In the present invention, the amount of the p-type dopant is not particularly limited and can be the amount known to those skilled in the art.

[0052] In the present invention, the hole transport layer 4 contains at least one of the hole transport materials of the present invention. The hole transport layer 4 may also contain any combination of at least one of the hole transport materials of the present invention and known hole transport materials. Currently known hole transport materials can be selected from at least one of the above-mentioned compounds HT-1 to HT-31, but are not limited to the listed compounds.

[0053] In the present invention, the luminescent material of the light-emitting layer 5 is not particularly limited, and any luminescent material known to those skilled in the art can be used. For example, the luminescent material may include a host material and a guest material. For example, it can be selected from at least one of the following compounds RH-1 to RH-13, but not limited thereto:

[0054]

[0055] The host material of the light-emitting layer can also be at least one of the known host materials for green light-emitting layers in the art. For example, it can be selected from at least one of the following compounds GPH-1 to GPH-80, but not limited thereto:

[0056]

[0057]

[0058]

[0059] The host material of the light-emitting layer can also be at least one of the known host materials for blue light-emitting layers in the art. For example, it can be selected from at least one of the following compounds BH-1 to BH-10, but not limited thereto:

[0060]

[0061] The guest material of the light-emitting layer can be a guest material for a red light-emitting layer. For example, it can be selected from at least one of the following compounds RPD-1 to RPD-28, but not limited thereto:

[0062]

[0063] The host material of the light-emitting layer can be a host material for a green light-emitting layer. For example, it can be selected from at least one of the following compounds GD01 to GD04, but not limited thereto:

[0064]

[0065] The host material of the light-emitting layer can be a host material for a blue light-emitting layer. For example, it can be selected from at least one of the following compounds BD-1 to BD-9, but not limited thereto:

[0066]

[0067] In the present invention, the material of the electron transport layer 6 is not particularly limited and can be made of electron transport materials well-known in the art. For example, the electron transport layer material can be selected from at least one of the following compounds ET-1 to ET-57:

[0068]

[0069]

[0070]

[0071]

[0072] In the present invention, the electron transport layer 6 can further include an n-type dopant. The type of the n-type dopant is not particularly limited, and various n-type dopants known in the art can be used. For example, the n-type dopant can be a compound represented by the following formula:

[0073]

[0074] In the present invention, the amount of the n-type dopant is not particularly limited and can be an amount well-known to those skilled in the art.

[0075] In the present invention, the material of the electron injection layer 7 is not particularly limited, and electron injection materials well-known in the art can be used. For example, it can include but not limited to at least one of the materials such as LiQ, LiF, NaCl, CsF, Li2O, Cs2CO3, BaO, Na, Li, Ca in the prior art.

[0076] In the present invention, the material of the cathode electrode 8 is not particularly limited. For example, it can be selected from but not limited to metals, metal mixtures, oxides such as magnesium-silver mixture, LiF / Al, ITO, Al, etc.

[0077] The display device provided by the present invention includes the organic electroluminescent device provided by the present invention. The display device includes, but is not limited to, a display, a television, a tablet computer, a mobile communication terminal, etc.

[0078] The method for preparing the organic electroluminescent device of the present invention is not particularly limited, and any method known in the art can be used. For example, the present invention can be prepared by the following preparation method:

[0079] (1) Clean the reflective anode electrode 2 on the top-emitting OLED device substrate 1, and in a cleaning machine, respectively perform steps such as chemical cleaning, water washing, brushing, high-pressure water washing, and air knife, and then perform heat treatment;

[0080] (2) Vacuum deposit a hole injection material on the reflective anode electrode 2 as the hole injection layer 3;

[0081] (3) Vacuum deposit a hole transport material on the hole injection layer 3 as the hole transport layer 4;

[0082] (4) Vacuum deposit a light-emitting layer 5 on the hole transport layer 4, and the light-emitting layer 5 contains a host material and a guest material;

[0083] (5) Vacuum deposit an electron transport material on the light-emitting layer 5 as the electron transport layer 6;

[0084] (6) Vacuum deposit an electron injection material on the electron transport layer 6 as the electron injection layer 7, and the electron injection material is selected from one or a combination of several materials such as LiQ, LiF, NaCl, CsF, Li2O, Cs2CO3, BaO, Na, Li, Ca, etc.;

[0085] (7) Vacuum deposit a cathode material on the electron injection layer 7 as the cathode electrode 8.

[0086] The above only describes the structure and its preparation method of a typical organic electroluminescent device. It should be understood that the present invention is not limited to this structure. The hole transport material of the present invention can be used in any structure of organic electroluminescent devices, and the organic electroluminescent devices can be prepared by any method known in the art.

[0087] The synthesis method of the compound of the present invention is not particularly limited, and any method known to those skilled in the art can be used for synthesis. The following is an example to illustrate the synthesis process of the compound of the present invention.

[0088] Synthesis Example 1: Synthesis of Compound A1

[0089]

[0090] After adding 108 g (0.50 mol) of 1-bromoadamantane to 188 g (2.0 mol) of phenol, the mixture was heated at 120 °C for 12 hours. After the reaction was completed, it was allowed to cool to room temperature and then added to a 2 L beaker while stirring for precipitation. After filtration, the precipitate was washed with hot water three times and dried thoroughly under vacuum to obtain M1.

[0091] 91 g (0.40 mol) of M1 and 63 g (0.80 mol) of pyridine were dissolved in 500 ml of dichloromethane. Then the temperature was lowered to 0 °C, and 135 g (0.48 mol) of trifluoromethanesulfonic anhydride was slowly added. After stirring for 3 hours, 300 ml of hydrochloric acid was added after the reaction was completed, and then 300 ml of water was added for extraction. The organic layer was dried with anhydrous magnesium chloride, and after distillation of the filtrate, column chromatography was carried out to obtain M2.

[0092] 100 mmol of M2, 100 mmol of bis(pinacolato)diboron, 28.83 g of sodium tert-butoxide (300 mmol), 800 ml of xylene were added to a reaction flask, and 1 mol% of bis(dibenzylideneacetone)palladium (Pd(dba)) was added. The reaction was carried out at 120 °C for 12 h, where the addition amount of Pd(dba) was 1 mol% of M2. After the reaction was completed, the reaction was stopped, and the reactant was cooled to room temperature, water was added, filtered, and washed with water. The obtained solid was purified by recrystallization with toluene to obtain white powder M3.

[0093] 100 mmol of M3, 100 mmol of 2-bromo-1-naphthol, 41.4 g of potassium carbonate (300 mmol), 800 ml of tetrahydrofuran (THF) and 200 ml of water were added to a reaction flask, and 1 mmol of tetrakis(triphenylphosphine)palladium (Pd(PPh3)4) was added. The reaction was carried out at 60 °C for 12 h. After the reaction was completed, the reaction was stopped, and the reactant was cooled to room temperature, water was added, the organic phase was concentrated to obtain a white solid, filtered, and washed with water. The obtained solid was purified by recrystallization with toluene to obtain white powder M4.

[0094] (0.40 mol) of M4 and (0.80 mol) of pyridine were dissolved in 500 ml of dichloromethane. Then the temperature was lowered to 0 °C, and (0.48 mol) of trifluoromethanesulfonic anhydride was slowly added. After stirring for 3 hours, 300 ml of hydrochloric acid was added after the reaction was completed, and then 300 ml of water was added for extraction. The organic layer was dried with anhydrous magnesium chloride, and after distillation of the filtrate, column chromatography was carried out to obtain M5.

[0095] Add 100 mmol of 2-iodo-3-bromophenol, 100 mmol of 4-chloro-2-fluorophenylboronic acid, 41.4 g of potassium carbonate (300 mmol), 800 ml of tetrahydrofuran (THF) and 200 ml of water into a reaction flask, and add 1 mol% of tetrakis(triphenylphosphine)palladium (Pd(PPh3)4). React at 60 °C for 12 h. After the reaction is completed, stop the reaction, cool the reactant to room temperature, add water, concentrate the organic phase to obtain a white solid, filter, wash with water, and recrystallize and purify the obtained solid with toluene to obtain white powder M6. Among them, the addition amount of Pd(PPh3)4 is 1 mol% of 2-iodo-3-bromophenol.

[0096] Add 100 mmol of M6, 41.4 g of potassium carbonate (300 mmol), and 800 ml of N,N-dimethylformamide (DMF) into a reaction flask, and react at 120 °C for 12 h. After the reaction is completed, stop the reaction, cool the reactant to room temperature, add water, concentrate the organic phase to obtain a white solid, filter, wash with water, and recrystallize and purify the obtained solid with toluene to obtain white powder M7.

[0097] Add 100 mmol of M7, 100 mmol of phenylboronic acid, 41.4 g of potassium carbonate (300 mmol), 800 ml of tetrahydrofuran (THF) and 200 ml of water into a reaction flask, and add 1 mol% of tetrakis(triphenylphosphine)palladium (Pd(PPh3)4). React at 60 °C for 12 h. After the reaction is completed, stop the reaction, cool the reactant to room temperature, add water, concentrate the organic phase to obtain a white solid, filter, wash with water, and recrystallize and purify the obtained solid with toluene to obtain white powder M8. Among them, the addition amount of Pd(PPh3)4 is 1 mol% of M7.

[0098] Add 100 mmol of M8, 100 mmol of 2-amino-9,9-dimethylfluorene, 28.83 g of sodium tert-butoxide (300 mmol), and 800 ml of xylene into a reaction flask, and add 1 mol% of bis(dibenzylideneacetone)palladium (Pd(dba)). React at 120 °C for 12 h, where the addition amount of Pd(dba) is 1 mol% of M8. After the reaction is completed, stop the reaction, cool the reactant to room temperature, add water, filter, wash with water, and recrystallize and purify the obtained solid with toluene to obtain white powder M9.

[0099] Add 100 mmol of M5, 100 mmol of M9, 28.83 g of sodium tert-butoxide (300 mmol), 800 ml of xylene into a reaction flask, and add 1 mol% of bis(dibenzylideneacetone)palladium (Pd(dba)). React at 120 °C for 12 h, wherein the addition amount of Pd(dba) is 1 mol% of M5. After the reaction is completed, stop the reaction, cool the reactant to room temperature, add water, filter, wash with water, and recrystallize and purify the obtained solid with toluene to obtain white powder A1.

[0100] 1 H NMR (400 MHz, Chloroform) δ 8.20 (d, J = 7.6 Hz, 1H), 8.03 (s, 1H), 7.96 (d, J = 7.6 Hz, 2H), 7.80 (d, J = 8.4 Hz, 1H), 7.76 (t, J = 7.6 Hz, 3H), 7.58 (d, J = 7.2 Hz, 2H), 7.50 (d, J = 7.6 Hz, 2H), 7.46 - 7.30 (m, 14H), 7.24 (t, J = 7.2 Hz, 1H), 7.00 (d, J = 7.6 Hz, 1H), 2.00 - 1.98 (m, 9H), 1.75 - 1.68 (m, 6H), 1.65 (s, 6H).

[0101] Synthesis Example 2: Synthesis of Compound A7

[0102]

[0103] Add 108 g (0.50 mol) of 1-bromoadamantane to 188 g (2.0 mol) of phenol, heat at 120 °C for 12 hours. After the reaction is completed, let it cool to room temperature, add it to a 2 L beaker and precipitate while stirring. After filtration, wash the precipitate with hot water 3 times, and obtain M1 after sufficient vacuum drying.

[0104] Dissolve 91 g (0.40 mol) of M1 and 63 g (0.80 mol) of pyridine in 500 ml of dichloromethane, then cool the temperature to 0 °C, and slowly add 135 g (0.48 mol) of trifluoromethanesulfonic anhydride. Stir for 3 hours. After the reaction is completed, add 300 ml of hydrochloric acid, and then add 300 ml of water for extraction. Dry the organic layer with anhydrous magnesium chloride, distill the filtrate, and perform column chromatography to obtain M2.

[0105] Add 100 mmol of M2, 100 mmol of 2-chlorophenylboronic acid, 41.4 g of potassium carbonate (300 mmol), 800 ml of tetrahydrofuran (THF) and 200 ml of water into a reaction flask, and add 1 mmol of tetrakis(triphenylphosphine)palladium (Pd(PPh3)4). React at 60 °C for 12 h. After the reaction is completed, stop the reaction, cool the reactant to room temperature, add water, concentrate the organic phase to obtain a white solid, filter, wash with water, and recrystallize and purify the obtained solid with toluene to obtain a white powder M3.

[0106] Add 100 mmol of 2-iodo-5-bromophenol, 100 mmol of 4-chloro-2-fluorophenylboronic acid, 41.4 g of potassium carbonate (300 mmol), 800 ml of tetrahydrofuran (THF) and 200 ml of water into a reaction flask, and add 1 mol% of tetrakis(triphenylphosphine)palladium (Pd(PPh3)4). React at 60 °C for 12 h. After the reaction is completed, stop the reaction, cool the reactant to room temperature, add water, concentrate the organic phase to obtain a white solid, filter, wash with water, and recrystallize and purify the obtained solid with toluene to obtain a white powder M4. Among them, the addition amount of Pd(PPh3)4 is 1 mol% of 2-iodo-5-bromophenol.

[0107] Add 100 mmol of M4, 41.4 g of potassium carbonate (300 mmol), and 800 ml of DMF into a reaction flask, and react at 120 °C for 12 h. After the reaction is completed, stop the reaction, cool the reactant to room temperature, add water, concentrate the organic phase to obtain a white solid, filter, wash with water, and recrystallize and purify the obtained solid with toluene to obtain a white powder M5.

[0108] Add 100 mmol of M5, 100 mmol of phenylboronic acid, 41.4 g of potassium carbonate (300 mmol), 800 ml of tetrahydrofuran (THF) and 200 ml of water into a reaction flask, and add 1 mol% of tetrakis(triphenylphosphine)palladium (Pd(PPh3)4). React at 60 °C for 12 h. After the reaction is completed, stop the reaction, cool the reactant to room temperature, add water, concentrate the organic phase to obtain a white solid, filter, wash with water, and recrystallize and purify the obtained solid with toluene to obtain a white powder M6. Among them, the addition amount of Pd(PPh3)4 is 1 mol% of M5.

[0109] 100 mmol of M6, 100 mmol of 2-amino-9,9-dimethylfluorene, 28.83 g of sodium tert-butoxide (300 mmol), 800 ml of xylene were added to a reaction flask, and 1 mol% of bis(dibenzylideneacetone)palladium (Pd(dba)) was added. The reaction was carried out at 120 °C for 12 h, where the addition amount of Pd(dba) was 1 mol% of M6. After the reaction was completed, the reaction was stopped, and the reactant was cooled to room temperature, water was added, filtered, washed with water, and the obtained solid was purified by recrystallization with toluene to obtain white powder M7.

[0110] 100 mmol of M3, 100 mmol of M7, 28.83 g of sodium tert-butoxide (300 mmol), 800 ml of xylene were added to a reaction flask, and 1 mol% of bis(dibenzylideneacetone)palladium (Pd(dba)) was added. The reaction was carried out at 120 °C for 12 h, where the addition amount of Pd(dba) was 1 mol% of M3. After the reaction was completed, the reaction was stopped, and the reactant was cooled to room temperature, water was added, filtered, washed with water, and the obtained solid was purified by recrystallization with toluene to obtain white powder A7.

[0111] 1 H NMR (400 MHz, Chloroform) δ 8.10 (d, J = 7.6 Hz, 1H), 8.03 (s, 1H), 7.96 (s, 1H), 7.90 (d, J = 8.0 Hz, 1H), 7.85 (d, J = 8.8 Hz, 1H), 7.75 (t, J = 7.6 Hz, 3H), 7.56 (d, J = 7.6 Hz, 3H), 7.52 - 7.40 (m, 6H), 7.39 - 7.26 (m, 5H), 7.22 (d, J = 6.8 Hz, 2H), 7.17 (d, J = 7.6 Hz, 2H), 2.00 - 1.98 (m, 9H), 1.75 - 1.68 (m, 6H), 1.66 (s, 6H).

[0112] Synthesis Example 3: Synthesis of Compound A13

[0113]

[0114] After adding 108 g (0.50 mol) of 1-bromoadamantane to 188 g (2.0 mol) of phenol and heating at 120 °C for 12 h until the reaction was completed, it was left to room temperature and then added to a 2 L beaker and precipitated with stirring. After filtration, the precipitate was washed 3 times with hot water and dried thoroughly under vacuum to obtain M1.

[0115] After dissolving 91 g (0.40 mol) of M1 and 63 g (0.80 mol) of pyridine in 500 ml of dichloromethane, the temperature was lowered to 0 °C, and 135 g (0.48 mol) of trifluoromethanesulfonic anhydride was slowly added. After stirring for 3 hours, 300 ml of hydrochloric acid was added after the reaction ended, and then 300 ml of water was added for extraction. The organic layer was dried with anhydrous magnesium chloride, and after distilling the filtrate, column chromatography was carried out to obtain M2.

[0116] 100 mmol of M2, 100 mmol of 2-chlorophenylboronic acid, 41.4 g of potassium carbonate (300 mmol), 800 ml of tetrahydrofuran (THF) and 200 ml of water were added to a reaction flask, and 1 mmol of tetrakis(triphenylphosphine)palladium (Pd(PPh3)4) was added. The reaction was carried out at 60 °C for 12 h. After the reaction was completed, the reaction was stopped, and the reactant was cooled to room temperature. Water was added, and the organic phase was concentrated to obtain a white solid. After filtration and washing with water, the obtained solid was purified by recrystallization with toluene to obtain a white powder M3.

[0117] 100 mmol of 2-iodo-5-bromophenol, 100 mmol of 5-chloro-2-fluorophenylboronic acid, 41.4 g of potassium carbonate (300 mmol), 800 ml of tetrahydrofuran (THF) and 200 ml of water were added to a reaction flask, and 1 mol% of tetrakis(triphenylphosphine)palladium (Pd(PPh3)4) was added. The reaction was carried out at 60 °C for 12 h. After the reaction was completed, the reaction was stopped, and the reactant was cooled to room temperature. Water was added, and the organic phase was concentrated to obtain a white solid. After filtration and washing with water, the obtained solid was purified by recrystallization with toluene to obtain a white powder M4. Among them, the addition amount of Pd(PPh3)4 was 1 mol% of 2-iodo-5-bromophenol.

[0118] 100 mmol of M4, 41.4 g of potassium carbonate (300 mmol), and 800 ml of DMF were added to a reaction flask, and the reaction was carried out at 120 °C for 12 h. After the reaction was completed, the reaction was stopped, and the reactant was cooled to room temperature. Water was added, and the organic phase was concentrated to obtain a white solid. After filtration and washing with water, the obtained solid was purified by recrystallization with toluene to obtain a white powder M5.

[0119] 100 mmol of M5, 100 mmol of diphenylamine, 28.83 g of sodium tert-butoxide (300 mmol), 800 ml of xylene were added to a reaction flask, and 1 mol% of bis(dibenzylideneacetone)palladium (Pd(dba)) was added. The reaction was carried out at 120 °C for 12 h, where the addition amount of Pd(dba) was 1 mol% of M5. After the reaction was completed, the reaction was stopped, and the reactant was cooled to room temperature. Water was added, and after filtration and washing with water, the obtained solid was purified by recrystallization with toluene to obtain a white powder M6.

[0120] Add 100 mmol of M6, 100 mmol of 2-amino-9,9-dimethylfluorene, 28.83 g of sodium tert-butoxide (300 mmol), 800 ml of xylene into a reaction flask, and add 1 mol% of bis(dibenzylideneacetone)palladium (Pd(dba)). React at 120 °C for 12 h, wherein the addition amount of Pd(dba) is 1 mol% of M6. After the reaction is completed, stop the reaction, cool the reactant to room temperature, add water, filter, wash with water, and recrystallize and purify the obtained solid with toluene to obtain white powder M7.

[0121] Add 100 mmol of M3, 100 mmol of M7, 28.83 g of sodium tert-butoxide (300 mmol), 800 ml of xylene into a reaction flask, and add 1 mol% of bis(dibenzylideneacetone)palladium (Pd(dba)). React at 120 °C for 12 h, wherein the addition amount of Pd(dba) is 1 mol% of M3. After the reaction is completed, stop the reaction, cool the reactant to room temperature, add water, filter, wash with water, and recrystallize and purify the obtained solid with toluene to obtain white powder A13.

[0122] 1 H NMR (400 MHz, Chloroform) δ8.22 (s, 1H), 8.10 (d, J = 7.2 Hz, 1H), 8.04 (s, 1H), 7.92 (d, J = 7.2 Hz, 1H), 7.85 (d, J = 8.4 Hz, 1H), 7.55 (d, J = 8.0 Hz, 1H), 7.52 (d, J = 7.6 Hz, 2H), 7.43 (d, J = 9.2 Hz, 3H), 7.39 - 7.12 (m, 14H), 7.08 (d, J = 7.2 Hz, 4H), 7.00 (t, J = 7.2 Hz, 2H), 2.00 - 1.98 (m, 9H), 1.75 - 1.68 (m, 6H), 1.66 (s, 6H).

[0123] Other compounds of the present invention can be synthesized by selecting appropriate raw materials according to the ideas of the above Synthesis Examples 1 - 3, or any other appropriate methods and raw materials can be selected for synthesis.

[0124] Example 1

[0125] Ultrasonically treat the glass plate coated with the ITO transparent conductive layer in a commercial cleaning agent, rinse it in deionized water, ultrasonically degrease it in an acetone-ethanol mixed solvent, bake it in a clean environment until all moisture is completely removed, clean it with ultraviolet light and ozone, and bombard the surface with a low-energy cation beam;

[0126] Place the above-mentioned glass substrate with the anode in a vacuum chamber, evacuate to less than 10 -5Torr. On the above-mentioned anode layer film, Al material was vacuum-evaporated as the hole injection layer at an evaporation rate of 0.1 nm / s, and the evaporated film thickness was 10 nm;

[0127] On the hole injection layer, Al material was vacuum-evaporated as the hole transport layer at an evaporation rate of 0.1 nm / s, and the evaporated film thickness was 80 nm;

[0128] On the hole transport layer, a light-emitting layer was vacuum-evaporated. The light-emitting layer included a host material BH-1 and a dye material BD-1, and the co-evaporation method with multiple sources was used for evaporation. The evaporation rate of the host material BH-1 was adjusted to 0.1 nm / s, and the evaporation rate of the dye BD-1 was 3% of the evaporation rate of the host material. The total evaporated film thickness was 30 nm;

[0129] On the light-emitting layer, an electron transport layer was vacuum-evaporated. The material ET-42 was selected as the electron transport material, and its evaporation rate was 0.1 nm / s, and the evaporated film thickness was 30 nm;

[0130] On the electron transport layer (ETL), LiF with a thickness of 0.5 nm was vacuum-evaporated as the electron injection layer at an evaporation rate of 0.1 nm / s;

[0131] Finally, on the electron injection layer, an aluminum layer with a thickness of 150 nm was evaporated as the cathode of the organic electroluminescent device at an evaporation rate of 0.1 nm / s.

[0132] Example 2-3

[0133] Except that A7 and A13 were used to replace A1 respectively, the rest was the same as in Example 1.

[0134] Comparative Example 1

[0135] Except that HT-29 was used to replace A1, the rest was the same as in Example 1.

[0136] The following performance measurements were carried out on the organic electroluminescent devices prepared by the above process, and the test results are shown in Table 1:

[0137] At the same brightness, a digital source meter and a luminance meter were used to measure the driving voltage, current efficiency and device lifetime of the organic electroluminescent devices prepared in the examples and comparative examples. Specifically, the voltage was increased at a rate of 0.1 V per second, and the voltage when the brightness of the organic electroluminescent device reached 1000 cd / m 2 was measured as the driving voltage, and the current density at this time was also measured; the ratio of brightness to current density was the current efficiency; the LT95 lifetime test was as follows: using a luminance meter at 1000 cd / m 2 brightness, keeping a constant current, measuring the time when the brightness of the organic electroluminescent device dropped to 950 cd / m 2 in hours.

[0138] Table 1. Performance Results of Organic Electroluminescent Devices

[0139]

[0140] As can be seen from the data in the above table, the compound prepared by the present invention is used as a hole transport material for organic electroluminescent devices, which can effectively reduce the driving voltage, improve the current efficiency, and extend the device life, and is a hole transport material with good performance.

[0141] Example 4

[0142] The glass plate coated with the ITO transparent conductive layer was ultrasonically treated in a commercial cleaning agent, rinsed in deionized water, ultrasonically degreased in an acetone-ethanol mixed solvent, baked in a clean environment until all moisture was removed, cleaned with ultraviolet light and ozone, and bombarded with a low-energy cation beam on the surface;

[0143] The above glass substrate with the anode was placed in a vacuum chamber, and the vacuum was pumped to less than 10 -5 Torr, and HT27 was vacuum-evaporated on the above anode layer film as the hole injection layer at a evaporation rate of 0.1 nm / s and a evaporation film thickness of 10 nm;

[0144] HT27 was vacuum-evaporated on the hole injection layer as the hole transport layer at a evaporation rate of 0.1 nm / s and a evaporation film thickness of 100 nm;

[0145] Al was vacuum-evaporated on the hole transport layer as the auxiliary light-emitting layer at a evaporation rate of 0.1 nm / s and a evaporation film thickness of 80 nm;

[0146] The light-emitting layer was vacuum-evaporated on the hole transport layer. The light-emitting layer includes the host material RH-12 and the dye material RPD-10, and the evaporation was carried out by the method of multi-source co-evaporation. The evaporation rate of the host material RH-12 was adjusted to 0.1 nm / s, and the evaporation rate of the dye RPD-10 was 5% of the evaporation rate of the host material, and the total evaporation film thickness was 30 nm;

[0147] The electron transport layer was vacuum-evaporated on the light-emitting layer. The material ET-42 was selected as the electron transport material, and its evaporation rate was 0.1 nm / s and the evaporation film thickness was 30 nm;

[0148] LiF with a thickness of 0.5 nm was vacuum-evaporated on the electron transport layer (ETL) as the electron injection layer at a evaporation rate of 0.1 nm / s;

[0149] Finally, an aluminum layer with a thickness of 150 nm was evaporated on the electron injection layer as the cathode of the organic electroluminescent device at a evaporation rate of 0.1 nm / s.

[0150] Examples 5 - 8

[0151] Except for replacing A1 with A7, A13, A18, and A22 respectively, the rest is the same as in Example 4.

[0152] Comparative Example 2

[0153] Except for replacing A1 with R1, the rest is the same as in Example 4.

[0154]

[0155] The following performance measurements were carried out on the organic electroluminescent devices prepared by the above process, and the test results are shown in Table 2:

[0156] At the same brightness, a digital source meter and a luminance meter were used to measure the driving voltage, current efficiency, and device lifetime of the organic electroluminescent devices prepared in the examples and comparative examples. Specifically, the voltage was increased at a rate of 0.1 V per second, and the voltage when the brightness of the organic electroluminescent device reached 5000 cd / m 2 was measured as the driving voltage, and the current density at this time was also measured; the ratio of brightness to current density was the current efficiency; the LT95 lifetime test was as follows: using a luminance meter at 5000 cd / m 2 brightness, keeping a constant current, and measuring the time when the brightness of the organic electroluminescent device dropped to 4750 cd / m 2 , with the unit of hours.

[0157] Table 2. Performance Results of Organic Electroluminescent Devices

[0158] Auxiliary light-emitting layer material <![CDATA[Required luminance cd / m 2 > Voltage V Current efficiency cd / A Lifetime (LT95) h Example 4 A1 5000.00 3.52 67.1 177 Example 5 A7 5000.00 3.57 67.0 170 Example 6 A13 5000.00 3.59 67.3 169 Example 7 A18 5000.00 3.61 67.5 180 Example 8 A22 5000.00 3.55 67.3 176 Comparative Example 2 R1 5000.00 3.75 66.0 152

[0159] As can be seen from the data in the above table, the compound prepared by the present invention is used as a light-emitting auxiliary layer material for organic electroluminescent devices, which can effectively reduce the driving voltage, improve the current efficiency, and extend the device lifetime, and is a hole transport material with good performance.

[0160] The above are only the preferred embodiments of the present invention and are not intended to limit the protection scope of the present invention. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present invention are included in the protection scope of the present invention.

Claims

1. An alkane-substituted compound, characterized in that, It has the structure shown in formula (Ⅰ): Among them, L 1 , L 2 are each independently selected from a chemical bond, a substituted or unsubstituted C6-C 30 aryl group, and a substituted or unsubstituted C5-C 30 heteroaryl group; R 1 、R 2 are each independently selected from C1-C4 alkyl, C3-C6 cycloalkane, substituted or unsubstituted C6-C 30 aryl, substituted or unsubstituted C5-C 30 heteroaryl, and adjacent substituents can be connected to form a ring; R and R' are each independently selected from hydrogen, a substituted or unsubstituted C6-C 30 aryl group, a substituted or unsubstituted C5-C 30 heteroaryl group; m, n, and o are each independently selected from 0, 1, 2, 3, 4; X is selected from O, S, N; Ar is selected from a substituted or unsubstituted C6-C 30 aryl group, a substituted or unsubstituted C5-C 30 heteroaryl group; A is selected from the following fragments: The heteroatoms on the heteroaryl are each independently selected from O, S, or N; The hydrogen atoms on the aryl group and heteroaryl group may each independently be replaced by Ra, and Ra are each independently selected from deuterium, halogen, nitro, cyano, C1-C4 alkyl, C5-C 20 cycloalkyl, phenyl, biphenyl, terphenyl or naphthyl.

2. The compound according to claim 1, wherein Ar is selected from a substituted or unsubstituted C6-C 24 aryl group, a substituted or unsubstituted C5-C 18 heteroaryl group.

3. The compound according to claim 1, wherein Said R 1 , R 2 are each independently selected from methyl, ethyl, isopropyl, tert-butyl, cyclopentyl, cyclohexyl, and the following groups which are unsubstituted or substituted by Ra: phenyl, biphenyl, naphthyl, fluorenyl, dibenzofuranyl, dibenzothiophenyl, carbazolyl.

4. The compound according to claim 1, wherein R and R' are each independently selected from hydrogen and the following groups which are unsubstituted or substituted by Ra: phenyl, biphenyl, terphenyl, naphthyl, phenanthryl, triphenylene, fluorenyl, dibenzofuranyl, dibenzothiophenyl, 9,9-dimethylfluorenyl, spirofluorenyl, arylamino group.

5. The compound according to claim 1, characterized in that, Ar is selected from the following groups which are unsubstituted or substituted by Ra: phenyl, biphenyl, terphenyl, naphthyl, phenanthryl, triphenylene, fluorenyl, benzofuranyl, dibenzofuranyl, benzothiophenyl, dibenzothiophenyl, 9,9-dimethylfluorenyl, spirofluorenyl, arylamino group, carbazolyl.

6. The compound according to claim 1, wherein Selected from the compounds shown in A1 - A20:

7. A hole transporting material, characterized in that, Comprising at least one of the compounds described in any one of claims 1 - 6.

8. An organic electroluminescent device, characterized in that, Comprising at least one of the hole transport materials of claim 7.

9. A display device, characterized in that, An organic electroluminescent device comprising the compound of claim 8.

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