A silicon-based substituted compound, a hole transport material and an organic electroluminescence device

Abstract

The application provides a silicon-based substituted compound of a general formula (I). The compound has a 1-dibenzofuran-substituted and phenyl-silicon-substituted arylamine parent structure, high bond energy between atoms, a large conjugated plane, is beneficial to solid-state stacking between molecules, and exhibits good thermodynamic stability. When used as a hole transport material, the compound has strong hole transition ability, can effectively reduce a device driving voltage, and improves a service life of the device. The application also provides a hole transport material containing the silicon-based substituted compound of the general formula (I), an organic electroluminescent device, and a display device.

Description

Technical Field

[0001] This application relates to the field of organic light-emitting display technology, and in particular to a silicon-based substituted compound, a hole transport material, and an organic electroluminescent device. Background Technology

[0002] Electroluminescence (EL) refers to the phenomenon where luminescent materials emit light when excited by an electric field and current. It is a process that directly converts electrical energy into light energy. Organic electroluminescent displays (OLEDs) possess a series of advantages, including self-illumination, low-voltage DC drive, all-solid-state operation, wide viewing angle, light weight, and simple composition and manufacturing process. Compared to liquid crystal displays (LCDs), OLEDs do not require a backlight, have a wider viewing angle, lower power consumption, and a response speed up to 1000 times faster than LCDs, while their manufacturing cost is lower than that of LCDs with equivalent resolution. Therefore, organic electroluminescent devices have a very broad application prospect.

[0003] With the continuous advancement of OLED technology in both lighting and display fields, research on organic materials that influence the performance of OLED devices has become increasingly focused. Typically, OLED device structures include the following types of organic materials: hole injection materials, hole transport materials, electron transport materials, and various luminescent materials (dyes or doped guest materials) and corresponding host materials. Among these, hole transport materials, as crucial functional materials, directly impact hole mobility, ultimately affecting the luminous efficiency of OLEDs. However, currently used hole transport materials in OLEDs exhibit low hole mobility, poor energy level matching with adjacent layers, and cannot simultaneously achieve both efficiency and lifetime, severely hindering the display functionality and development of OLED display devices. Summary of the Invention

[0004] The purpose of this application is to provide a hole transport material to reduce the driving voltage, improve the luminous efficiency, and extend the lifespan of organic electroluminescent devices. The specific technical solution is as follows:

[0005] The first aspect of this application provides a silicon-based substituted compound, the structural formula of which is shown in general formula (I):

[0006]

[0007] in,

[0008] R1-R2 are independently selected from C1-C4 alkyl, C3-C6 cycloalkyl, unsubstituted or Ra-substituted groups of the following: C6-C30 aromatic groups or C5-C30 heteroaryl groups;

[0009] R3 -R 6 The R group is independently selected from hydrogen, C1-C4 alkyl, C3-C5 cycloalkyl, C2-C6 alkenyl, hydroxyl, aniline, and the following groups, either unsubstituted or substituted with Ra: amino, C6-C30 aromatic, or C5-C30 heteroaryl, wherein the R group is... 3 -R 6 Two adjacent groups can connect to form a ring;

[0010] R 7 -R 9 The R group is independently selected from hydrogen, C1-C4 alkyl, C3-C5 cycloalkyl, C2-C6 alkenyl, unsubstituted or Ra-substituted groups of the following: amino, C6-C30 aryl, or C5-C30 heteroaryl, wherein the R group is... 7 -R 9 Two adjacent groups can connect to form a ring;

[0011] L1 is selected from chemical bonds, C6-C30 aromatic alkyl groups, or C5-C30 heteroaryl groups;

[0012] L2 is selected from chemical bonds, C6-C30 aromatic alkyl groups, or C5-C30 heteroaryl groups;

[0013] Ar is selected from the following groups, either unsubstituted or substituted by Ra: aromatic groups of C6-C30, heteroaryl groups of C5-C30, or aromatic amino groups;

[0014] The heteroatoms on the heteroaryl group or the heteroaryl group are each independently selected from O, S or N;

[0015] The Ra is independently selected from deuterium, halogen, nitro, cyano, C1-C4 alkyl, C5-C20 cycloalkyl, phenyl, biphenyl, terphenyl, naphthyl, phenylsilyl or benzocyclohexyl.

[0016] A second aspect of this application provides a hole transport material comprising at least one of the silicon-based substituted compounds provided in the first aspect of this application.

[0017] A third aspect of this application provides an organic electroluminescent device comprising at least one of the hole transport materials provided in the second aspect of this application.

[0018] A fourth aspect of this application provides a display device that includes the organic electroluminescent device provided in the third aspect of this application.

[0019] The beneficial effects of this application are:

[0020] This application provides a silicon-based substituted compound of general formula (I), which has a parent structure of 1-dibenzofuran-substituted and phenylsilane-substituted aromatic amines. It exhibits high interatomic bond energy, a large conjugated plane, which facilitates solid-state packing and demonstrates good thermodynamic stability. When used as a hole transport material, it exhibits strong hole transition capability, effectively reducing device driving voltage and improving device lifespan. As a hole transport material, the compound of this application enables the organic electroluminescent device provided by this application to have a lower device driving voltage, higher luminous efficiency, and longer lifespan. The display device provided by this application has excellent display performance. Attached Figure Description

[0021] To more clearly illustrate the technical solutions in the embodiments of this application, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of this application. For those skilled in the art, other embodiments can be obtained based on these accompanying drawings.

[0022] Figure 1 This is a schematic diagram of a typical organic electroluminescent device. Detailed Implementation

[0023] The technical solutions of this application will be clearly and completely described below with reference to the embodiments and accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. All other embodiments obtained by those skilled in the art based on this application are within the scope of protection of this application.

[0024] The first aspect of this application provides a silicon-based substituted compound, the structural formula of which is shown in general formula (I):

[0025]

[0026] in,

[0027] R1-R2 are independently selected from C1-C4 alkyl, C3-C6 cycloalkyl, unsubstituted or Ra-substituted groups of the following: C6-C30 aromatic groups or C5-C30 heteroaryl groups;

[0028] R 3 -R 6 The R group is independently selected from hydrogen, C1-C4 alkyl, C3-C5 cycloalkyl, C2-C6 alkenyl, hydroxyl, aniline, and the following groups, either unsubstituted or substituted with Ra: amino, C6-C30 aromatic, or C5-C30 heteroaryl, wherein the R group is... 3 -R 6 Two adjacent groups can connect to form a ring;

[0029] R 7 -R 9 The R group is independently selected from hydrogen, C1-C4 alkyl, C3-C5 cycloalkyl, C2-C6 alkenyl, unsubstituted or Ra-substituted groups of the following: amino, C6-C30 aryl, or C5-C30 heteroaryl, wherein the R group is... 7 -R 9 Two adjacent groups can connect to form a ring;

[0030] L1 is selected from chemical bonds, C6-C30 aromatic alkyl groups, or C5-C30 heteroaryl groups;

[0031] L2 is selected from chemical bonds, C6-C30 aromatic alkyl groups, or C5-C30 heteroaryl groups;

[0032] Ar is selected from the following groups, either unsubstituted or substituted by Ra: aromatic groups of C6-C30, heteroaryl groups of C5-C30, or aromatic amino groups;

[0033] The heteroatoms on the heteroaryl group or the heteroaryl group are each independently selected from O, S or N;

[0034] The Ra is independently selected from deuterium, halogen, nitro, cyano, C1-C4 alkyl, C5-C20 cycloalkyl, phenyl, biphenyl, terphenyl, naphthyl, phenylsilyl or benzocyclohexyl.

[0035] Preferably, R1-R2 are independently selected from C1-C4 alkyl, C3-C6 cycloalkyl, unsubstituted or Ra-substituted groups of the following: C6-C18 aromatic groups or C5-C18 heteroaryl groups;

[0036] Preferably, R 3 -R 6 The R group is independently selected from hydrogen, C1-C4 alkyl, C3-C5 cycloalkyl, C2-C6 alkenyl, hydroxyl, aniline, and the following groups, either unsubstituted or substituted with Ra: amino, C6-C18 aryl, or C6-18 heteroaryl, wherein the R group is... 3 -R 6 Two adjacent groups can connect to form a ring;

[0037] Preferably, R 7 -R 9 The R group is independently selected from hydrogen, C1-C4 alkyl, C3-C5 cycloalkyl, C2-C6 alkenyl, unsubstituted or Ra-substituted groups of the following: amino, C6-C18 aryl or C5-C18 heteroaryl, wherein the R group is... 7 -R 9 Two adjacent groups can connect to form a ring;

[0038] Preferably, Ar is selected from the following groups, either unsubstituted or substituted by Ra: C6-C18 aromatic groups, C5-C18 heteroaryl groups, or aromatic amino groups;

[0039] Preferably, the Ra is independently selected from deuterium, halogen, C1-C4 alkyl, C5-C20 cycloalkyl, phenyl, biphenyl, terphenyl or naphthyl.

[0040] More preferably, R1-R2 are independently selected from methyl, ethyl, isopropyl, tert-butyl, cyclopentyl, cyclohexyl, unsubstituted or Ra-substituted groups of the following: phenyl, biphenyl, naphthyl, phenanthrene, fluorenyl, dibenzofuranyl, dibenzothiopheneyl or carbazoyl.

[0041] More preferably, R 3 -R 6 The R group is independently selected from hydrogen, methyl, ethyl, isopropyl, tert-butyl, cyclopropyl, cyclopentyl, vinyl, hydroxyl, aniline, and the following groups, either unsubstituted or substituted with Ra: amino, phenyl, biphenyl, terphenyl, naphthyl, phenanthrene, triphenylene, fluorenyl, dibenzofuranyl, dibenzothiophene, 9,9-dimethylfluorenyl, or spirofluorenyl. 3 -R 6 Two adjacent groups can connect to form a ring.

[0042] More preferably, R 7 -R 9 The R group is independently selected from hydrogen, methyl, ethyl, isopropyl, tert-butyl, cyclopropyl, cyclopentyl, vinyl, unsubstituted or Ra-substituted groups of the following: amino, phenyl, biphenyl, terphenyl, naphthyl, phenanthrene, triphenylene, fluorenyl, dibenzofuranyl, dibenzothiophene, 9,9-dimethylfluorenyl or spirofluorenyl, wherein the R group is... 7 -R 9 Two adjacent groups can connect to form a ring.

[0043] More preferably, Ar is selected from the following groups, either unsubstituted or substituted by Ra: phenyl, biphenyl, terphenyl, naphthyl, phenanthrene, triphenylene, fluorenyl, biphenylamino, benzofuranyl, dibenzofuranyl, benzothiophene, dibenzothiophene, 9,9-dimethylfluorenyl, phenylfluorenyl, spirofluorenyl, aromatic amino, carbazole, or fluoranthene.

[0044] More preferably, L1 is selected from chemical bonds, phenylene, biphenylene, terphenylene, naphthylene, phenanthrene, terphenylene, fluorene, benzofuranyl or dibenzofuranyl.

[0045] More preferably, L2 is selected from chemical bonds, phenylene, biphenylene, terphenylene, naphthylene, phenanthrene, terphenylene, fluorene, benzofuranyl or dibenzofuranyl.

[0046] In some embodiments, the silicon-based substituted compound is selected from the compounds shown in A1-A55 below:

[0047]

[0048]

[0049]

[0050]

[0051] The inventors discovered that the silicon-based substituted compound provided in this application has a parent structure of 1-dibenzofuran-substituted and phenylsilane-substituted aromatic amines. It exhibits high interatomic bond energy, good thermal stability, and facilitates solid-state molecular stacking. Its strong hole transition capability allows it to be used as a hole transport layer material, effectively reducing the device's driving voltage and extending its lifespan. Simultaneously, the substitution sites of the 1-dibenzofuran provide significant steric hindrance, deepening the Highest Occupied Molecular Orbital (HOMO) level. The introduction of the phenylsilane fragment stabilizes the compound, improving its thermal stability and thus extending the lifespan of organic electroluminescent devices. Furthermore, the introduction of the phenylsilane fragment reduces the refractive index of the hole transport layer material, improving light transmittance and reducing losses, thereby increasing the luminous efficiency of the organic electroluminescent device.

[0052] The second aspect of this application provides a hole transport material comprising at least one of the silicon-based substituted compounds provided in the first aspect of this application.

[0053] When the silicon-based substituted compound provided in this application is used as a hole transport material, it has a suitable energy level with adjacent layers, which is conducive to hole injection and migration. It can effectively reduce the driving voltage of organic electroluminescent devices, while having a high hole migration rate. As a light-emitting auxiliary layer material, it enables organic electroluminescent devices to achieve good luminous efficiency. It also has a large conjugated plane, which is conducive to molecular stacking and exhibits good thermodynamic stability, making organic electroluminescent devices exhibit long lifetime.

[0054] A third aspect of this application provides an organic electroluminescent device comprising at least one of the hole transport materials provided in the second aspect of this application. The organic electroluminescent device provided in this application has a lower driving voltage, higher luminous efficiency, and longer lifespan.

[0055] In this application, there are no particular restrictions on the type and structure of organic electroluminescent devices. They can be organic electroluminescent devices of different types and structures known in the art, as long as the hole transport material provided in this application can be used.

[0056] The organic electroluminescent device of this application can be a top-emitting structure, for example, comprising an anode, a hole injection layer, a hole transport layer, an emitting layer, an electron transport layer (ETL), an electron injection layer, and a transparent or semi-transparent cathode in sequence on a substrate.

[0057] The organic electroluminescent device of this application can also be a bottom-emitting device, for example, comprising a transparent or semi-transparent anode, a hole injection layer, a hole transport layer, an emitting layer, an electron transport layer, an electron injection layer and a cathode structure in sequence on a substrate.

[0058] The organic electroluminescent device of this application can also be a light-emitting device with a dual-sided light-emitting structure, for example, comprising 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 in sequence on a substrate.

[0059] In the organic electroluminescent device of this application, except for the hole transport layer which contains the hole transport material provided in this application, other layers can use any material used for the layers in the prior art.

[0060] Furthermore, the organic electroluminescent device of this application may have an electron blocking layer between the hole transport layer and the light-emitting layer, and a hole blocking layer between the light-emitting layer and the electron transport layer. A light extraction layer may be disposed on the transparent electrode on the light-emitting side. However, the structure of the organic electroluminescent device of this application is not limited to the specific structure described above. If necessary, the above layers may be omitted or added. This application does not impose any particular limitation on the thickness of the above layers, as long as the purpose of this application can be achieved. For example, the organic electroluminescent device may sequentially include an anode (100nm to 150nm), a hole injection layer (5nm to 20nm), a hole transport layer (80nm to 140nm), an electron blocking layer (5nm to 20nm), a light-emitting layer (20nm to 45nm), a hole blocking layer (5nm to 20nm), an electron transport layer (30nm to 40nm), an electron injection layer (0.5nm to 20nm), a transparent or semi-transparent cathode (100nm to 200nm), and a light extraction layer (50nm to 90nm) on a substrate.

[0061] Figure 1 A schematic diagram of a typical organic electroluminescent device is shown, 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 arranged sequentially.

[0062] Understandable. Figure 1 The diagram only schematically illustrates the structure of a typical organic electroluminescent device. This application is not limited to this structure, and the hole transport material of this application can be used in any type of organic electroluminescent device. For example, organic electroluminescent devices may also include an electron blocking layer, a hole blocking layer, a light extraction layer, etc. In practical applications, these layers can be added or omitted depending on the specific circumstances.

[0063] For convenience, the following references Figure 1 The organic electroluminescent device described in this application is not intended to limit the scope of protection of this application. It is understood that all organic electroluminescent devices capable of using the hole transport material of this application are within the scope of protection of this application.

[0064] In this application, substrate 1 is not particularly limited and can be any conventional substrate used in organic electroluminescent devices in the prior art, such as glass, polymer materials, and glass and polymer materials with thin-film transistor (TFT) components.

[0065] In this application, the material of the reflective anode electrode 2 is not particularly limited. 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), and low-temperature polycrystalline silicon (LTPS). It can also be metallic materials such as silver and its alloys, aluminum and its alloys, or organic conductive materials such as poly(3,4-ethylenedioxythiophene) (PEDOT). Alternatively, it can be a multilayer structure formed from the above materials. This application does not particularly limit the number of layers in its multilayer structure. It can be selected according to actual needs, as long as it can achieve the purpose of this application. For example, one layer, two layers, three layers, or more layers.

[0066] In this application, there are no particular restrictions on the material of the hole injection layer 3. Hole injection materials known in the art or hole transport materials provided in this application can be selected as hole injection materials.

[0067] For example, the material of the hole injection layer 3 may be selected from at least one of the following HT-1 to HT-31 compounds:

[0068]

[0069]

[0070] In this application, the hole injection layer 3 may further include a p-type dopant. The type of 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 may be selected from at least one of the following compounds:

[0071]

[0072] In this application, the amount of p-type dopant used is not particularly limited and can be any amount known to those skilled in the art.

[0073] In this application, hole transport layer 4 comprises at least one of the hole transport materials described herein. Hole transport layer 4 may also comprise any combination of at least one of the hole transport materials described herein and known hole transport materials. Currently known hole transport materials may be selected from at least one of the compounds listed above, from HT-1 to HT-31, but are not limited to the compounds listed above. The number of layers in hole transport layer 4 is not particularly limited and can be adjusted according to actual needs, as long as it meets the purpose of this application; for example, 1 layer, 2 layers, 3 layers, 4 layers, or more.

[0074] In this application, the luminescent material of the luminescent 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 comprise a host material and a guest material. For instance, known host materials for the luminescent layer may be selected from, but are not limited to, at least one of the following compounds: BH-1 to BH-10.

[0075]

[0076] In this application, there is no particular limitation on the amount of the main material of the light-emitting layer, and it can be any amount known to those skilled in the art.

[0077] In this application, there are no particular limitations on the guest material of the luminescent layer, and at least one of the luminescent layer guest materials known in the art can be used. For example, the luminescent layer guest material can be selected from, but is not limited to, at least one of the following BD-1 to BD-9 compounds:

[0078]

[0079] In this application, the material of the electron transport layer 6 is not particularly limited and can be made of electron transport materials known in the art. For example, the electron transport layer material can be selected from at least one of the following ET-1 to ET-57 compounds:

[0080]

[0081]

[0082]

[0083]

[0084] In this application, the electron transport layer 6 may further include an n-type dopant. The type of 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 may be a compound represented by the following formula:

[0085]

[0086] In this application, there is no particular limitation on the amount of the n-type dopant, and it can be any amount known to those skilled in the art.

[0087] In this application, there are no particular limitations on the material of the electron injection layer 7. Electron injection materials known in the art can be used, such as at least one of the following materials in the prior art: LiQ (lithium 8-hydroxyquinoline), LiF, NaCl, CsF, Li2O, Cs2CO3, BaO, Na, Li, Ca, etc.

[0088] In this application, the material of the cathode electrode 8 is not particularly limited. For example, it can be selected from, but is not limited to, magnesium-silver mixtures, LiF / Al, ITO, Al and other metals, metal mixtures, oxides and the like.

[0089] There are no particular limitations on the method for preparing the organic electroluminescent device of this application; any method known in the art can be used. For example, this application can be prepared using the following method:

[0090] (1) Clean the reflective anode electrode 2 on the substrate 1 of the top-emitting OLED device. In the cleaning machine, the electrode is cleaned by chemical washing, water washing, brushing, high-pressure water washing, air knife and other steps, and then heated.

[0091] (2) Hole injection material is vacuum-deposited on the reflective anode electrode 2 as a hole injection layer 3;

[0092] (3) Hole transport material is vacuum-deposited on hole injection layer 3 as hole transport layer 4;

[0093] (4) A light-emitting layer 5 is vacuum-deposited on the hole transport layer 4, the light-emitting layer 5 containing a host material and a guest material;

[0094] (5) Electron transport material is vacuum-deposited on the light-emitting layer 5 as electron transport layer 6;

[0095] (6) Vacuum evaporation of electron injection material on electron transport layer 6 to form electron injection layer 7. 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, and Ca.

[0096] (7) Vacuum evaporation of cathode material on electron injection layer 7 as cathode electrode 8.

[0097] The above describes only a typical structure and fabrication method of an organic electroluminescent device. It should be understood that this application is not limited to this structure. The hole transport material of this application can be used in organic electroluminescent devices of any structure, and the organic electroluminescent device can be fabricated using any fabrication method known in the art.

[0098] A fourth aspect of this application provides a display device comprising the organic electroluminescent device provided in this application. The display device includes, but is not limited to, a monitor, a television, a tablet computer, a mobile communication terminal, etc.

[0099] There are no particular limitations on the synthesis method of the compounds in this application; any method known to those skilled in the art can be used for synthesis. The following examples illustrate the synthesis process of the compounds in this application. As used herein, room temperature refers to 25±5℃.

[0100] Synthesis example

[0101] Synthesis Example 1: Synthesis of Compound A1

[0102]

[0103] 100 mmol of aniline, 100 mmol of 1-bromo-dibenzofuran, 28.83 g of sodium tert-butoxide (300 mmol), and 800 mL of xylene were added to a reaction flask, along with 1 mol% of bis(dba)2-dibenzylacetone palladium (Pd(dba)2). The reaction was carried out at 120 °C for 12 h. After the reaction was completed, the reaction was stopped, and the reactants were cooled to room temperature. Water was added, the mixture was filtered, washed with water, and the resulting solid was purified by recrystallization from toluene to obtain a white powder M1. The amount of Pd(dba)2 added was 1 mol% of aniline.

[0104] 100 mmol of M1, 100 mmol of 4-bromo-tetraphenylsilane, 28.83 g of sodium tert-butoxide (300 mmol), and 800 ml of xylene were added to a reaction flask, along with 1 mol% of Pd(dba)2. The reaction was carried out at 120 °C for 12 h. After the reaction was complete, the reaction was stopped, and the reactants were cooled to room temperature. Water was added, the mixture was filtered, washed with water, and the resulting solid was purified by recrystallization from toluene to obtain a white powder, Al. The amount of Pd(dba)2 added was 1 mol% of M1.

[0105] 1H NMR(400MHz,Chloroform)δ7.98(d,J=8.0Hz,1H),7.56(d,J=8.0Hz,1H),7.50–7.42(m,7 H),7.40–7.34(m,11H),7.30–7.14(m,8H),7.08(d,J=13.2Hz,2H),7.00(t,J=7.2Hz,1H).

[0106] Synthesis Example 2: Synthesis of Compound A2

[0107]

[0108] 100 mmol of 4-aminobiphenyl, 100 mmol of 1-bromo-dibenzofuran, 28.83 g of sodium tert-butoxide (300 mmol), and 800 mL of xylene were added to a reaction flask, along with 1 mol% of Pd(dba)₂. The reaction was carried out at 120 °C for 12 h. After the reaction was completed, the reaction was stopped, and the reactants were cooled to room temperature. Water was added, the mixture was filtered, washed with water, and the resulting solid was purified by recrystallization from toluene to obtain a white powder M1. The amount of Pd(dba)₂ added was 1 mol% of 4-aminobiphenyl.

[0109] 100 mmol of M1, 100 mmol of 4-bromo-tetraphenylsilane, 28.83 g of sodium tert-butoxide (300 mmol), and 800 ml of xylene were added to a reaction flask, along with 1 mol% of Pd(dba)2. The reaction was carried out at 120 °C for 12 h. After the reaction was complete, the reaction was stopped, and the reactants were cooled to room temperature. Water was added, the mixture was filtered, washed with water, and the resulting solid was purified by recrystallization from toluene to obtain a white powder A2. The amount of Pd(dba)2 added was 1 mol% of M1.

[0110] 1 H NMR(400MHz,Chloroform)δ7.98(d,J=7.2Hz,1H),7.76(d,J=7.6Hz,2H),7.56(d,J=7.2Hz,3H),7.5 0-7.40(m,9H),7.38–7.32(m,14H),7.30–7.20(m,4H),7.20(d,J=7.2Hz,1H),7.14(t,J=7.2Hz,1H).

[0111] Synthesis Example 3: Synthesis of Compound A6

[0112]

[0113] 100 mmol of aniline, 100 mmol of 1-bromo-dibenzofuran, 28.83 g of sodium tert-butoxide (300 mmol), and 800 ml of xylene were added to a reaction flask, along with 1 mol% of Pd(dba)₂. The reaction was carried out at 120 °C for 12 h. After the reaction was complete, the reaction was stopped, and the reactants were cooled to room temperature. Water was added, the mixture was filtered, washed with water, and the resulting solid was purified by recrystallization from toluene to obtain a white powder M1. The amount of Pd(dba)₂ added was 1 mol% of aniline.

[0114] 100 mmol of 4-bromo-tetraphenylsilane, 100 mmol of pinacol diborate, 41.4 g of potassium carbonate (300 mmol), and 800 ml of toluene were added to a reaction flask, along with 1 mmol of tetra(triphenylphosphine)palladium (Pd(PPh3)4). The reaction was carried out at 100 °C for 12 h. After the reaction was completed, the reaction was stopped, and the reactants were cooled to room temperature. Water was added, and the mixture was separated. The organic phase was concentrated to obtain a white solid, which was filtered, washed with water, and the solid was purified by recrystallization from toluene to obtain a white powder M2.

[0115] 100 mmol of 1,4-dibromonaphthalene, 100 mmol of M2, 41.4 g of potassium carbonate (300 mmol), 800 mL of tetrahydrofuran (THF), and 200 mL of water were added to a reaction flask, along with 1 mmol of Pd(PPh3)4. The reaction was carried out at 60 °C for 12 h. After the reaction was completed, the reaction was stopped, and the reactants were cooled to room temperature. Water was added, the mixture was separated, and the organic phase was concentrated to obtain a white solid. The solid was filtered, washed with water, and purified by recrystallization from toluene to obtain a white powder M3.

[0116] 100 mmol of M1, 100 mmol of M3, 28.83 g of sodium tert-butoxide (300 mmol), and 800 ml of xylene were added to a reaction flask, along with 1 mol% of Pd(dba)2. The reaction was carried out at 120 °C for 12 h. After the reaction was complete, the reaction was stopped, and the reactants were cooled to room temperature. Water was added, the mixture was filtered, washed with water, and the resulting solid was purified by recrystallization from toluene to obtain a white powder A6. The amount of Pd(dba)2 added was 1 mol% of M1.

[0117] 1H NMR (400MHz, Chloroform) δ8.95(d,J=7.6Hz,1H),8.28(d,J=7.6Hz,1H),7.98(d,J=7.6Hz,1H),7.88(d,J=8.4Hz,2H),7.66( d,J=8.4Hz,2H),7.54(d,J=8.0Hz,2H),7.50–7.40(m,7H),7.38–7.18(m,18H),7.10(d,J=7.6Hz,2H),7.02(t,J=7.6Hz,1H).

[0118] Synthesis Example 4: Synthesis of Compound A7

[0119]

[0120] 100 mmol of carbazole, 100 mmol of 4-fluoronitrobenzene, 41.4 g of potassium carbonate (300 mmol), and 800 ml of N,N-dimethylformamide (DMF) were added to a reaction flask, and the mixture was reacted at 120 °C for 12 h. After the reaction was completed, the reaction was stopped, and the reactants were cooled to room temperature. Water was added, the mixture was filtered, washed with water, and the resulting solid was purified by recrystallization from toluene to obtain a white powder M1.

[0121] 100 mmol of M1, 200 mmol of stannous chloride, 400 mL of ethanol, and 400 mL of ethyl acetate were added to a reaction flask, and the mixture was reacted at 70 °C for 8 h. After the reaction was completed, the reaction was stopped, and the reactants were cooled to room temperature. A 30 wt% potassium carbonate aqueous solution was added, the mixture was filtered, washed with water, and the filtrate was separated. The organic phase was concentrated, and the resulting solid was purified by recrystallization from toluene to obtain a white powder, M2.

[0122] 100 mmol of M2, 100 mmol of 1-bromo-dibenzofuran, 28.83 g of sodium tert-butoxide (300 mmol), and 800 ml of xylene were added to a reaction flask, along with 1 mol% of Pd(dba)2. The reaction was carried out at 120 °C for 12 h. After the reaction was complete, the reaction was stopped, and the reactants were cooled to room temperature. Water was added, the mixture was filtered, washed with water, and the resulting solid was purified by recrystallization from toluene to obtain a white powder, M3. The amount of Pd(dba)2 added was 1 mol% of M2.

[0123] 100 mmol of M3, 100 mmol of 4-bromo-tetraphenylsilane, 28.83 g of sodium tert-butoxide (300 mmol), and 800 ml of xylene were added to a reaction flask, along with 1 mol% of Pd(dba)2. The reaction was carried out at 120 °C for 12 h. After the reaction was complete, the reaction was stopped, and the reactants were cooled to room temperature. Water was added, the mixture was filtered, washed with water, and the resulting solid was purified by recrystallization from toluene to obtain a white powder A7. The amount of Pd(dba)2 added was 1 mol% of M3.

[0124] 1 H NMR (400MHz, Chloroform) δ8.55(d,J=7.2Hz,1H),8.18(d,J=7.6Hz,1H),7.98(d,J=8.0Hz,1H),7.68(d,J=8. 8Hz,2H),7.54(t,J=7.2Hz,2H),7.48–7.40(m,7H),7.39–7.30(m,14H),7.28-7.21(m,5H),7.17-7.08(m,5H).

[0125] Synthesis Example 5: Synthesis of Compound A9

[0126]

[0127] 100 mmol of 3-aminodibenzofuran, 100 mmol of 4-bromo-tetraphenylsilane, 28.83 g of sodium tert-butoxide (300 mmol), and 800 ml of xylene were added to a reaction flask, along with 1 mol% of Pd(dba)₂. The reaction was carried out at 120 °C for 12 h. After the reaction was complete, the reaction was stopped, and the reactants were cooled to room temperature. Water was added, the mixture was filtered, washed with water, and the resulting solid was purified by recrystallization from toluene to obtain a white powder M1. The amount of Pd(dba)₂ added was 1 mol% of 3-aminodibenzofuran.

[0128] 100 mmol of 2-bromo-5-chlorofluorobenzene, 100 mmol of pinacol diborate, 28.83 g of sodium tert-butoxide (300 mmol), and 800 ml of xylene were added to a reaction flask, along with 1 mol% of Pd(dba)₂. The reaction was carried out at 120 °C for 12 h. After the reaction was complete, the reaction was stopped, and the reactants were cooled to room temperature. Water was added, the mixture was filtered, washed with water, and the resulting solid was purified by recrystallization from toluene to obtain a white powder M₂. The amount of Pd(dba)₂ added was 1 mol% of 2-bromo-5-chlorofluorobenzene.

[0129] 100 mmol of M2, 100 mmol of 2,6-dihydroxybromobenzene, 41.4 g of potassium carbonate (300 mmol), 800 ml of THF, and 200 ml of water were added to a reaction flask, along with 1 mmol of Pd(PPh3)4. The reaction was carried out at 60 °C for 12 h. After the reaction was completed, the reaction was stopped, and the reactants were cooled to room temperature. Water was added, the mixture was separated, and the organic phase was concentrated to obtain a white solid. The solid was filtered, washed with water, and purified by recrystallization from toluene to obtain a white powder, M3.

[0130] 100 mmol of M3, 41.4 g of potassium carbonate (300 mmol), and 800 ml of DMF were added to a reaction flask. The reaction was carried out at 120 °C for 12 h. After the reaction was completed, the reaction was stopped, and the reactants were cooled to room temperature. Water was added, the mixture was separated, and the organic phase was concentrated to obtain a white solid. The solid was filtered, washed with water, and the obtained solid was purified by recrystallization from toluene to obtain a white powder M4.

[0131] 100 mmol of M4, 100 mmol of phenylboronic acid, 41.4 g of potassium carbonate (300 mmol), 800 ml of THF, and 200 ml of water were added to a reaction flask, along with 1 mmol of Pd(PPh3)4. The reaction was carried out at 60 °C for 12 h. After the reaction was completed, the reaction was stopped, and the reactants were cooled to room temperature. Water was added, the mixture was separated, and the organic phase was concentrated to obtain a white solid. The solid was filtered, washed with water, and then purified by recrystallization from toluene to obtain a white powder, M5.

[0132] 100 mmol of M5, 800 mL of dichloromethane, and 20 mL of triethylamine were added to a reaction flask. 150 mmol of trifluoromethanesulfonate was added dropwise at 0 °C, and the reaction was allowed to proceed for 12 h. After the reaction was complete, the reaction was stopped, and the reactants were added to water. The mixture was separated, and the organic phase was concentrated to obtain a white solid. The solid was filtered, washed with water, and then recrystallized from toluene to obtain a white powder, M6.

[0133] 100 mmol of M1, 100 mmol of M6, 28.83 g of sodium tert-butoxide (300 mmol), and 800 ml of xylene were added to a reaction flask, along with 1 mol% of Pd(dba)2. The reaction was carried out at 120 °C for 12 h. After the reaction was complete, the reaction was stopped, and the reactants were cooled to room temperature. Water was added, the mixture was filtered, washed with water, and the resulting solid was purified by recrystallization from toluene to obtain a white powder A9. The amount of Pd(dba)2 added was 1 mol% of M1.

[0134] 1H NMR (400MHz, Chloroform) δ8.08(s,1H),8.02(s,1H),7.96(d,J=7.2Hz,1H),7.76(t,J=7.2Hz,3H),7. 58(d,J=7.6Hz,3H),7.50–7.41(m,9H),7.38–7.30(m,12H),7.27–7.11(m,6H),7.16(d,J=7.2Hz,1H).

[0135] Synthesis Example 6: Synthesis of Compound A10

[0136]

[0137] 100 mmol of 3-aminodibenzothiophene, 100 mmol of 1-bromo-dibenzofuran, 28.83 g of sodium tert-butoxide (300 mmol), and 800 mL of xylene were added to a reaction flask, along with 1 mol% of Pd(dba)₂. The reaction was carried out at 120 °C for 12 h. After the reaction was complete, the reaction was stopped, and the reactants were cooled to room temperature. Water was added, the mixture was filtered, washed with water, and the resulting solid was purified by recrystallization from toluene to obtain a white powder M1. The amount of Pd(dba)₂ added was 1 mol% of 3-aminodibenzothiophene.

[0138] 100 mmol of M1, 100 mmol of 4-bromo-tetraphenylsilane, 28.83 g of sodium tert-butoxide (300 mmol), and 800 ml of xylene were added to a reaction flask, along with 1 mol% of Pd(dba)2. The reaction was carried out at 120 °C for 12 h. After the reaction was complete, the reaction was stopped, and the reactants were cooled to room temperature. Water was added, the mixture was filtered, washed with water, and the resulting solid was purified by recrystallization from toluene to obtain a white powder, Al0. The amount of Pd(dba)2 added was 1 mol% of M1.

[0139] 1 H NMR (400MHz, Chloroform) δ8.46(d,J=6.8Hz,1H),7.98(d,J=6.8Hz,2H),7.86(d,J=6.8Hz,1H),7.74(d,J=7.2Hz,1H),7.56(t,J=7.2H z,2H),7.50-7.45(m,6H),7.42(d,J=7.6Hz,2H),7.40-7.35(m,10H),7.33–7.21(m,6H),7.16(d,J=7.2Hz,1H),7.04(d,J=6.8Hz,1H).

[0140] Synthesis Example 7: Synthesis of Compound A12

[0141]

[0142] 100 mmol of 2-bromophenol, 100 mmol of pinacol diborate, 41.4 g of potassium carbonate (300 mmol), and 800 mL of toluene were added to a reaction flask, along with 1 mmol of Pd(PPh3)4. The reaction was carried out at 100 °C for 12 h. After the reaction was completed, the reaction was stopped, and the reactants were cooled to room temperature. Water was added, and the organic phase was concentrated to obtain a white solid. The solid was filtered, washed with water, and then purified by recrystallization from toluene to obtain a white powder M1.

[0143] 100 mmol of M1, 100 mmol of 2-bromo-3-chlorofluorobenzene, 41.4 g of potassium carbonate (300 mmol), 800 ml of THF, and 200 ml of water were added to a reaction flask, along with 1 mmol of Pd(PPh3)4. The reaction was carried out at 60 °C for 12 h. After the reaction was completed, the reaction was stopped, and the reactants were cooled to room temperature. Water was added, the mixture was separated, and the organic phase was concentrated to obtain a white solid. The solid was filtered, washed with water, and the obtained solid was purified by recrystallization from toluene to obtain a white powder M2.

[0144] 100 mmol of M2, 41.4 g of potassium carbonate (300 mmol), and 800 ml of DMF were added to a reaction flask. The reaction was carried out at 120 °C for 12 h. After the reaction was completed, the reaction was stopped, and the reactants were cooled to room temperature. Water was added, the mixture was separated, and the organic phase was concentrated to obtain a white solid. The solid was filtered, washed with water, and the obtained solid was purified by recrystallization from toluene to obtain a white powder M3.

[0145] 100 mmol of M3, 100 mmol of aniline, 28.83 g of sodium tert-butoxide (300 mmol), and 800 ml of xylene were added to a reaction flask, along with 1 mol% of Pd(dba)2. The reaction was carried out at 120 °C for 12 h. After the reaction was complete, the reaction was stopped, and the reactants were cooled to room temperature. Water was added, the mixture was filtered, washed with water, and the resulting solid was purified by recrystallization from toluene to obtain a white powder, M4. The amount of Pd(dba)2 added was 1 mol% of M3.

[0146] 100 mmol of M4, 100 mmol of 4-bromo-tetraphenylsilane, 28.83 g of sodium tert-butoxide (300 mmol), and 800 ml of xylene were added to a reaction flask, along with 1 mol% of Pd(dba)2. The reaction was carried out at 120 °C for 12 h. After the reaction was complete, the reaction was stopped, and the reactants were cooled to room temperature. Water was added, the mixture was filtered, washed with water, and the resulting solid was purified by recrystallization from toluene to obtain a white powder, Al2. The amount of Pd(dba)2 added was 1 mol% of M4.

[0147] 1H NMR(400MHz,Chloroform)δ7.84(d,J=6.8Hz,2H),7.60(d,J=7.2Hz,1H),7.50-7.42(m,9 H),7.40-7.31(m,10H),7.29–7.16(m,8H),7.10(d,J=7.6Hz,2H),7.04(t,J=7.2Hz,1H).

[0148] Synthesis Example 8: Synthesis of Compound A14

[0149]

[0150] 100 mmol of 1-aminodibenzofuran, 100 mmol of 2-bromo-9,9-diphenylfluorene, 28.83 g of sodium tert-butoxide (300 mmol), and 800 ml of xylene were added to a reaction flask, along with 1 mol% of Pd(dba)₂. The reaction was carried out at 120 °C for 12 h. After the reaction was complete, the reaction was stopped, and the reactants were cooled to room temperature. Water was added, the mixture was filtered, washed with water, and the resulting solid was purified by recrystallization from toluene to obtain a white powder M1. The amount of Pd(dba)₂ added was 1 mol% of 1-aminodibenzofuran.

[0151] 100 mmol of M1, 100 mmol of 4-bromo-tetraphenylsilane, 28.83 g of sodium tert-butoxide (300 mmol), and 800 ml of xylene were added to a reaction flask, along with 1 mol% of Pd(dba)2. The reaction was carried out at 120 °C for 12 h. After the reaction was complete, the reaction was stopped, and the reactants were cooled to room temperature. Water was added, the mixture was filtered, washed with water, and the resulting solid was purified by recrystallization from toluene to obtain a white powder, Al4. The amount of Pd(dba)2 added was 1 mol% of M1.

[0152] 1 H NMR (400MHz, Chloroform) δ8.04(d,J=6.8Hz,1H),7.96(d,J=6.8Hz,1H),7.90(d,J=6.8Hz,1H),7.84(d,J=8.0Hz,1H),7.76(s, 1H),7.55(d,J=6.8Hz,1H),7.50–7.42(m,7H),7.40–7.34(m,13H),7.30–7.25(m,10H),7.22–7.10(m,3H),7.06(d,J=8.0Hz,4H)

[0153] Synthesis Example 9: Synthesis of Compound A15

[0154]

[0155] 100 mmol of 2,5-dibromocatechol, 100 mmol of 2-fluorophenylboronic acid, 41.4 g of potassium carbonate (300 mmol), 800 mL of THF, and 200 mL of water were added to a reaction flask, along with 1 mmol of Pd(PPh3)4. The reaction was carried out at 60 °C for 12 h. After the reaction was completed, the reaction was stopped, and the reactants were cooled to room temperature. Water was added, and the mixture was separated. The organic phase was concentrated to obtain a white solid, which was filtered, washed with water, and the solid was purified by recrystallization from toluene to obtain a white powder M1.

[0156] 100 mmol of M1, 100 mmol of 2-chloro-6-fluorophenylboronic acid, 41.4 g of potassium carbonate (300 mmol), 800 ml of THF, and 200 ml of water were added to a reaction flask, along with 1 mmol of Pd(PPh3)4. The reaction was carried out at 60 °C for 12 h. After the reaction was completed, the reaction was stopped, and the reactants were cooled to room temperature. Water was added, the mixture was separated, and the organic phase was concentrated to obtain a white solid. The solid was filtered, washed with water, and purified by recrystallization from toluene to obtain a white powder, M2.

[0157] 100 mmol of M2, 41.4 g of potassium carbonate (300 mmol), and 800 ml of DMF were added to a reaction flask. The reaction was carried out at 120 °C for 12 h. After the reaction was completed, the reaction was stopped, and the reactants were cooled to room temperature. Water was added, the mixture was separated, and the organic phase was concentrated to obtain a white solid. The solid was filtered, washed with water, and the obtained solid was purified by recrystallization from toluene to obtain a white powder M3.

[0158] 100 mmol of M3, 100 mmol of aniline, 28.83 g of sodium tert-butoxide (300 mmol), and 800 ml of xylene were added to a reaction flask, along with 1 mol% of Pd(dba)2. The reaction was carried out at 120 °C for 12 h. After the reaction was complete, the reaction was stopped, and the reactants were cooled to room temperature. Water was added, the mixture was filtered, washed with water, and the resulting solid was purified by recrystallization from toluene to obtain a white powder, M4. The amount of Pd(dba)2 added was 1 mol% of M3.

[0159] 100 mmol of M4, 100 mmol of 4-bromo-tetraphenylsilane, 28.83 g of sodium tert-butoxide (300 mmol), and 800 ml of xylene were added to a reaction flask, along with 1 mol% of Pd(dba)2. The reaction was carried out at 120 °C for 12 h. After the reaction was complete, the reaction was stopped, and the reactants were cooled to room temperature. Water was added, the mixture was filtered, washed with water, and the resulting solid was purified by recrystallization from toluene to obtain a white powder, A15. The amount of Pd(dba)2 added was 1 mol% of M4.

[0160] 1H NMR(400MHz,Chloroform)δ7.98(d,J=7.2Hz,1H),7.62(d,J=8.0Hz,1H),7.54(d,J=6.8Hz,1H),7.50–7.42(m,7H),7.39–7.3 0(m,12H),7.30(d,J=7.2Hz,2H),7.23(d,J=7.6Hz,4H),7.18(d,J=6.8Hz,2H),7.08(d,J=7.2Hz,2H),7.00(t,J=7.2Hz,1H).

[0161] Synthesis Example 10: Synthesis of Compound A17

[0162]

[0163] 100 mmol of p-chlorobromobenzene, 100 mmol of diphenylmethylsilane, 41.4 g of potassium carbonate (300 mmol), and 800 ml of toluene were added to a reaction flask, along with 1 mmol of Pd(PPh3)4. The reaction was carried out at 100 °C for 12 h. After the reaction was completed, the reaction was stopped, and the reactants were cooled to room temperature. Water was added, and the mixture was separated. The organic phase was concentrated to obtain a white solid, which was filtered, washed with water, and the solid was purified by recrystallization from toluene to obtain a white powder M1.

[0164] 100 mmol of M1, 100 mmol of aniline, 28.83 g of sodium tert-butoxide (300 mmol), and 800 ml of xylene were added to a reaction flask, along with 1 mol% of Pd(dba)2. The reaction was carried out at 120 °C for 12 h. After the reaction was complete, the reaction was stopped, and the reactants were cooled to room temperature. Water was added, the mixture was filtered, washed with water, and the resulting solid was purified by recrystallization from toluene to obtain a white powder, M2. The amount of Pd(dba)2 added was 1 mol% of M1.

[0165] 100 mmol of 2-bromo-5-chlorofluorobenzene, 100 mmol of pinacol diborate, 28.83 g of sodium tert-butoxide (300 mmol), and 800 ml of xylene were added to a reaction flask, along with 1 mol% of Pd(dba)₂. The reaction was carried out at 120 °C for 12 h. After the reaction was complete, the reaction was stopped, and the reactants were cooled to room temperature. Water was added, the mixture was filtered, washed with water, and the resulting solid was purified by recrystallization from toluene to obtain a white powder M₃. The amount of Pd(dba)₂ added was 1 mol% of 2-bromo-5-chlorofluorobenzene.

[0166] 100 mmol of M3, 100 mmol of 2,6-dihydroxybromobenzene, 41.4 g of potassium carbonate (300 mmol), 800 mL of THF, and 200 mL of water were added to a reaction flask, along with 1 mmol of Pd(PPh3)4. The reaction was carried out at 60 °C for 12 h. After the reaction was completed, the reaction was stopped, and the reactants were cooled to room temperature. Water was added, the mixture was separated, and the organic phase was concentrated to obtain a white solid. The solid was filtered, washed with water, and purified by recrystallization from toluene to obtain a white powder, M4.

[0167] 100 mmol of M4, 41.4 g of potassium carbonate (300 mmol), and 800 ml of DMF were added to a reaction flask. The reaction was carried out at 120 °C for 12 h. After the reaction was completed, the reaction was stopped, and the reactants were cooled to room temperature. Water was added, the mixture was separated, and the organic phase was concentrated to obtain a white solid. The solid was filtered, washed with water, and the obtained solid was purified by recrystallization from toluene to obtain a white powder M5.

[0168] 100 mmol of M5, 100 mmol of phenylboronic acid, 41.4 g of potassium carbonate (300 mmol), 800 ml of THF, and 200 ml of water were added to a reaction flask, along with 1 mmol of Pd(PPh3)4. The reaction was carried out at 60 °C for 12 h. After the reaction was completed, the reaction was stopped, and the reactants were cooled to room temperature. Water was added, the mixture was separated, and the organic phase was concentrated to obtain a white solid. The solid was filtered, washed with water, and then purified by recrystallization from toluene to obtain a white powder, M6.

[0169] 100 mmol of M6, 800 mL of dichloromethane, and 20 mL of triethylamine were added to a reaction flask. 150 mmol of trifluoromethanesulfonate was then added dropwise at 0 °C, and the reaction was allowed to proceed for 12 h. After the reaction was complete, the reaction was stopped, and the reactants were added to water. The mixture was separated, and the organic phase was concentrated to obtain a white solid. The solid was filtered, washed with water, and then recrystallized from toluene to obtain a white powder, M7.

[0170] 100 mmol of M2, 100 mmol of M7, 28.83 g of sodium tert-butoxide (300 mmol), and 800 ml of xylene were added to a reaction flask, along with 1 mol% of Pd(dba)2. The reaction was carried out at 120 °C for 12 h. After the reaction was complete, the reaction was stopped, and the reactants were cooled to room temperature. Water was added, the mixture was filtered, washed with water, and the resulting solid was purified by recrystallization from toluene to obtain a white powder, A17. The amount of Pd(dba)2 added was 1 mol% of M2.

[0171] 1H NMR(400MHz,Chloroform)δ7.93(s,1H),7.78(d,J=7.2Hz,1H),7.70(d,J=8.0Hz,2H),7.58(d,J=7.2Hz ,1H),7.50–7.34(m,15H),7.30–7.12(m,7H),7.08(d,J=7.6Hz,2H),7.02(t,J=7.2Hz,1H),0.66(s,3H).

[0172] Synthesis Example 11: Synthesis of Compound A23

[0173]

[0174] 100 mmol of aniline, 100 mmol of 1-bromo-dibenzofuran, 28.83 g of sodium tert-butoxide (300 mmol), and 800 mL of xylene were added to a reaction flask, along with 1 mol% of Pd(dba)₂. The reaction was carried out at 120 °C for 12 h. After the reaction was complete, the reaction was stopped, and the reactants were cooled to room temperature. Water was added, the mixture was filtered, washed with water, and the resulting solid was purified by recrystallization from toluene to obtain a white powder M1. The amount of Pd(dba)₂ added was 1 mol% of aniline.

[0175] 100 mmol of M1, 100 mmol of 1-hydroxy-7-bromodibenzofuran, 28.83 g of sodium tert-butoxide (300 mmol), and 800 ml of xylene were added to a reaction flask, along with 1 mol% of Pd(dba)2. The reaction was carried out at 120 °C for 12 h. After the reaction was complete, the reaction was stopped, and the reactants were cooled to room temperature. Water was added, the mixture was filtered, washed with water, and the resulting solid was purified by recrystallization from toluene to obtain a white powder, M2. The amount of Pd(dba)2 added was 1 mol% of M1.

[0176] 100 mmol of M2, 800 ml of dichloromethane, and 20 ml of triethylamine were added to a reaction flask. 150 mmol of trifluoromethanesulfonate was then added dropwise at 0 °C, and the reaction was allowed to proceed for 12 h. After the reaction was complete, water was added to the reactants, and the mixture was separated. The organic phase was concentrated to obtain a white solid, which was filtered, washed with water, and the solid was purified by recrystallization from toluene to obtain a white powder, M3.

[0177] 100 mmol of M3, 100 mmol of pinacol diborate, 28.83 g of sodium tert-butoxide (300 mmol), and 800 ml of xylene were added to a reaction flask, along with 1 mol% of Pd(dba)2. The reaction was carried out at 120 °C for 12 h. After the reaction was complete, the reaction was stopped, and the reactants were cooled to room temperature. Water was added, the mixture was filtered, washed with water, and the resulting solid was purified by recrystallization from toluene to obtain a white powder, M4. The amount of Pd(dba)2 added was 1 mol% of M3.

[0178] 100 mmol of M4, 100 mmol of 4-bromo-tetraphenylsilane, 28.83 g of sodium tert-butoxide (300 mmol), and 800 ml of xylene were added to a reaction flask, along with 1 mol% of Pd(dba)2. The reaction was carried out at 120 °C for 12 h. After the reaction was complete, the reaction was stopped, and the reactants were cooled to room temperature. Water was added, the mixture was filtered, washed with water, and the resulting solid was purified by recrystallization from toluene to obtain a white powder, A23. The amount of Pd(dba)2 added was 1 mol% of M4.

[0179] 1 H NMR (400MHz, Chloroform) δ8.06(s,1H),8.00(d,J=7.6Hz,1H),7.88(d,J=7.6Hz,2H),7.64(d,J=7.6Hz,2H),7.55(t,J= 7.6Hz,4H),7.50–7.38(m,8H),7.35–7.26(m,10H),7.25(t,J=7.6Hz,4H),7.06(d,J=7.2Hz,4H),7.00(t,J=7.6Hz,1H).

[0180] Synthesis Example 12: Synthesis of Compound A32

[0181]

[0182] 100 mmol of 4-bromo-tetraphenylsilane, 100 mmol of 1-amino-dibenzofuran, 28.83 g of sodium tert-butoxide (300 mmol), and 800 ml of xylene were added to a reaction flask, along with 1 mol% of Pd(dba)₂. The reaction was carried out at 120 °C for 12 h. After the reaction was complete, the reaction was stopped, and the reactants were cooled to room temperature. Water was added, the mixture was filtered, washed with water, and the resulting solid was purified by recrystallization from toluene to obtain a white powder M1. The amount of Pd(dba)₂ added was 1 mol% of 4-bromo-tetraphenylsilane.

[0183] 100 mmol of 4-bromo-tetraphenylsilane, 100 mmol of 4-chlorophenylboronic acid, 41.4 g of potassium carbonate (300 mmol), 800 ml of THF, and 200 ml of water were added to a reaction flask, along with 1 mmol of Pd(PPh3)4. The reaction was carried out at 60 °C for 12 h. After the reaction was completed, the reaction was stopped, and the reactants were cooled to room temperature. Water was added, the mixture was separated, and the organic phase was concentrated to obtain a white solid. The solid was filtered, washed with water, and purified by recrystallization from toluene to obtain a white powder M2.

[0184] 100 mmol of M1, 100 mmol of M2, 28.83 g of sodium tert-butoxide (300 mmol), and 800 ml of xylene were added to a reaction flask, along with 1 mol% of Pd(dba)2. The reaction was carried out at 120 °C for 12 h. After the reaction was complete, the reaction was stopped, and the reactants were cooled to room temperature. Water was added, the mixture was filtered, washed with water, and the resulting solid was purified by recrystallization from toluene to obtain a white powder, A32. The amount of Pd(dba)2 added was 1 mol% of M1.

[0185] 1 H NMR (400MHz, Chloroform) δ7.98(d,J=8.0Hz,1H),7.86(d,J=7.6Hz,2H),7.65(d,J=7.6Hz,2H),7.55( d,J=8.0Hz,3H),7.50–7.40(m,13H),7.38-7.26(m,23H),7.25(d,J=7.2Hz,4H),7.15(d,J=7.2Hz,1H).

[0186] Synthesis Example 13: Synthesis of Compound A42

[0187]

[0188] 100 mmol of p-chlorobromobenzene, 100 mmol of dimethylphenylsilane, 41.4 g of potassium carbonate (300 mmol), and 800 ml of toluene were added to a reaction flask, along with 1 mmol of Pd(PPh3)4. The reaction was carried out at 100 °C for 12 h. After the reaction was completed, the reaction was stopped, and the reactants were cooled to room temperature. Water was added, and the mixture was separated. The organic phase was concentrated to obtain a white solid, which was filtered, washed with water, and the solid was purified by recrystallization from toluene to obtain a white powder M1.

[0189] 100 mmol of p-chlorobromobenzene, 100 mmol of N-phenyl-1-naphthylamine, 28.83 g of sodium tert-butoxide (300 mmol), and 800 ml of xylene were added to a reaction flask, along with 1 mol% of Pd(dba)₂. The reaction was carried out at 120 °C for 12 h. After the reaction was complete, the reaction was stopped, and the reactants were cooled to room temperature. Water was added, the mixture was filtered, washed with water, and the resulting solid was purified by recrystallization from toluene to obtain a white powder M₂. The amount of Pd(dba)₂ added was 1 mol% of p-chlorobromobenzene.

[0190] 100 mmol of p-bromoaniline, 100 mmol of pinacol diborate, 28.83 g of sodium tert-butoxide (300 mmol), and 800 ml of xylene were added to a reaction flask, along with 1 mol% of Pd(dba)₂. The reaction was carried out at 120 °C for 12 h. After the reaction was complete, the reaction was stopped, and the reactants were cooled to room temperature. Water was added, the mixture was filtered, washed with water, and the resulting solid was purified by recrystallization from toluene to obtain a white powder M₃. The amount of Pd(dba)₂ added was 1 mol% of p-bromoaniline.

[0191] 100 mmol of M2, 100 mmol of M3, 41.4 g of potassium carbonate (300 mmol), 800 ml of THF, and 200 ml of water were added to a reaction flask, along with 1 mmol of Pd(PPh3)4. The reaction was carried out at 60 °C for 12 h. After the reaction was completed, the reaction was stopped, and the reactants were cooled to room temperature. Water was added, the mixture was separated, and the organic phase was concentrated to obtain a white solid. The solid was filtered, washed with water, and the obtained solid was purified by recrystallization from toluene to obtain a white powder, M4.

[0192] 100 mmol of M1, 100 mmol of M4, 28.83 g of sodium tert-butoxide (300 mmol), and 800 ml of xylene were added to a reaction flask, along with 1 mol% of Pd(dba)2. The reaction was carried out at 120 °C for 12 h. After the reaction was complete, the reaction was stopped, and the reactants were cooled to room temperature. Water was added, the mixture was filtered, washed with water, and the resulting solid was purified by recrystallization from toluene to obtain a white powder, M5. The amount of Pd(dba)2 added was 1 mol% of M1.

[0193] 100 mmol of M5, 100 mmol of 1-bromodibenzofuran, 28.83 g of sodium tert-butoxide (300 mmol), and 800 ml of xylene were added to a reaction flask, along with 1 mol% of Pd(dba)2. The reaction was carried out at 120 °C for 12 h. After the reaction was complete, the reaction was stopped, and the reactants were cooled to room temperature. Water was added, the mixture was filtered, washed with water, and the resulting solid was purified by recrystallization from toluene to obtain a white powder, A42. The amount of Pd(dba)2 added was 1 mol% of M5.

[0194] 1 H NMR(400MHz,Chloroform)δ8.24(d,J=7.2Hz,1H),7.98(d,J=7.2Hz,1H),7.86(d,J=6.8Hz,1H),7.60–7.52 (m,7H),7.48–7.32(m,15H),7.33–7.12(m,8H),7.06(d,J=7.6Hz,2H),7.00(d,J=7.2Hz,1H),0.66(s,6H).

[0195] Synthesis Example 14: Synthesis of Compound A47

[0196]

[0197] 100 mmol of diphenylamine, 100 mmol of 1-hydroxy-7-bromodibenzofuran, 28.83 g of sodium tert-butoxide (300 mmol), and 800 ml of xylene were added to a reaction flask, along with 1 mol% of Pd(dba)₂. The reaction was carried out at 120 °C for 12 h. After the reaction was complete, the reaction was stopped, and the reactants were cooled to room temperature. Water was added, the mixture was filtered, washed with water, and the resulting solid was purified by recrystallization from toluene to obtain a white powder M1. The amount of Pd(dba)₂ added was 1 mol% of diphenylamine.

[0198] 100 mmol of M1, 800 mL of dichloromethane, and 20 mL of triethylamine were added to a reaction flask. 150 mmol of trifluoromethanesulfonate was added dropwise at 0 °C, and the reaction was allowed to proceed for 12 h. After the reaction was complete, the reaction was stopped, and the reactants were added to water. The mixture was separated, and the organic phase was concentrated to obtain a white solid. The solid was filtered, washed with water, and then recrystallized from toluene to obtain a white powder, M2.

[0199] 100 mmol of M2, 100 mmol of aniline, 28.83 g of sodium tert-butoxide (300 mmol), and 800 ml of xylene were added to a reaction flask, along with 1 mol% of Pd(dba)2. The reaction was carried out at 120 °C for 12 h. After the reaction was complete, the reaction was stopped, and the reactants were cooled to room temperature. Water was added, the mixture was filtered, washed with water, and the resulting solid was purified by recrystallization from toluene to obtain a white powder, M3. The amount of Pd(dba)2 added was 1 mol% of M2.

[0200] 100 mmol of M3, 100 mmol of 4-bromo-tetraphenylsilane, 28.83 g of sodium tert-butoxide (300 mmol), and 800 ml of xylene were added to a reaction flask, along with 1 mol% of Pd(dba)2. The reaction was carried out at 120 °C for 12 h. After the reaction was complete, the reaction was stopped, and the reactants were cooled to room temperature. Water was added, the mixture was filtered, washed with water, and the resulting solid was purified by recrystallization from toluene to obtain a white powder, A47. The amount of Pd(dba)2 added was 1 mol% of M3.

[0201] 1 H NMR(400MHz,Chloroform)δ8.05(s,1H),7.56(d,J=8.0Hz,1H),7.50–7.44(m,7H),7.42–7.29 (m,10H),7.30–7.20(m,9H),7.18–7.10(m,3H),7.10(d,J=7.2Hz,6H),7.01(t,J=7.2Hz,3H).

[0202] Other compounds in this application can be synthesized by selecting suitable starting materials according to the above synthetic examples, or by selecting any other suitable method and starting materials.

[0203] Example 1

[0204] A glass plate coated with a 150nm thick 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 to obtain a glass substrate with an anode.

[0205] The glass substrate with the anode was placed in a vacuum chamber and evacuated to a vacuum level of less than 10. -5 HT-11 was vacuum-deposited as a hole injection layer on the aforementioned anolyte film at a deposition rate of 0.1 nm / s, resulting in a film thickness of 10 nm. The hole injection material HT-11 is as follows:

[0206]

[0207] Compound A1 of this application was vacuum-deposited as a hole transport layer on top of the hole injection layer at a deposition rate of 0.1 nm / s and a film thickness of 80 nm. The hole transport material compound A1 is as follows:

[0208]

[0209] A light-emitting layer is vacuum-deposited on top of the hole transport layer. The light-emitting layer comprises a host material BH-2 and a guest material BD-3. The deposition is performed using a multi-source co-evaporation method. The deposition rate of the host material BH-2 is adjusted to 0.1 nm / s, and the deposition rate of the guest material BD-3 is 3% of the deposition rate of the host material. The total film thickness is 30 nm. The host material BH-2 and the guest material BD-3 are as follows:

[0210]

[0211] ET-27 was vacuum-deposited on top of the luminescent layer as an electron transport layer at a deposition rate of 0.1 nm / s and a film thickness of 30 nm. The electron transport material ET-27 is as follows:

[0212]

[0213] A 0.5 nm thick LiF layer was vacuum-deposited on the electron transport layer as an electron injection layer at a deposition rate of 0.1 nm / s.

[0214] Finally, an aluminum layer with a thickness of 150 nm was deposited on the electron injection layer as the cathode of the organic electroluminescent device at a deposition rate of 0.1 nm / s.

[0215] Examples 2 to 15

[0216] Except that the hole transport material is replaced by compounds A2, A6, A7, A9, A12, A14, A15, A16, A17, A23, A32, A42, and A47 respectively, the rest is the same as in Example 1.

[0217] Comparative Example 1

[0218] Except for replacing A1 with HT-27 as the hole transport material, everything else is the same as in Example 1; HT-27 is as follows:

[0219]

[0220] Comparative Example 2

[0221] Except for replacing A1 with HT-R as the hole transport material, everything else is the same as in Example 1; HT-R is as follows:

[0222]

[0223] The organic electroluminescent devices prepared by the above process were subjected to the following performance measurements:

[0224] Under the same brightness, the driving voltage, current efficiency, and lifetime of the organic electroluminescent devices prepared in the examples and comparative examples were measured using a digital source meter and a luminance meter. Specifically, the voltage was increased at a rate of 0.1V per second, and the measurement was performed when the brightness of the organic electroluminescent device reached 1000 cd / m². 2 The voltage at that time is the driving voltage, and the current density at that time is measured simultaneously; the ratio of brightness to current density is the current efficiency; the LT95 life test is as follows: using a luminance meter at 1000 cd / m² 2 At a constant current, the brightness of the organic electroluminescent device decreased to 950 cd / m² under the specified brightness. 2 The time is in hours. The test results are shown in Table 1.

[0225] Table 1 Performance results of organic electroluminescent devices

[0226] / Hole transport materials <![CDATA[require brightness cd / m 2 > Drive voltage V Current efficiency cd / A Lifespan (LT95)h Example 1 A1 1000.00 3.42 7.82 141 Example 2 A2 1000.00 3.44 7.79 143 Example 3 A6 1000.00 3.51 7.77 140 Example 4 A7 1000.00 3.47 7.80 143 Example 5 A9 1000.00 3.46 7.81 140 Example 6 A10 1000.00 3.47 7.76 142 Example 7 A12 1000.00 3.46 7.75 138 Example 8 A14 1000.00 3.44 7.76 143 Example 9 A15 1000.00 3.45 7.80 141 Example 10 A16 1000.00 3.44 7.75 140 Example 11 A17 1000.00 3.50 7.72 143 Example 12 A23 1000.00 3.48 7.72 145 Example 13 A32 1000.00 3.47 7.79 144 Example 14 A42 1000.00 3.45 7.78 145 Example 15 A47 1000.00 3.42 7.76 139 Comparative Example 1 HT-27 1000.00 3.62 7.58 118 Comparative Example 2 HT-R 1000.00 3.60 7.60 120

[0227] As shown in Table 1, compared with Comparative Examples 1-2, using the compounds of this application as hole transport materials in organic electroluminescent devices results in significantly lower driving voltage, significantly higher current efficiency, and significantly longer LT95 lifetime. Specifically, as shown in Example 2 and Comparative Example 2, the positions of the dibenzofuran linked to the aromatic amine differ between the two structures. The organic electroluminescent device using the compound of general formula I of this application, as shown in Example 2, exhibits significantly better driving voltage, current efficiency, and lifetime than that of Comparative Example 2.

[0228] The above results indicate that the compound provided in this application, when used as a hole transport material in organic electroluminescent devices, can effectively reduce the driving voltage, improve current efficiency, and extend device life, making it a high-performance hole transport material.

[0229] The above description is only a preferred embodiment of this application and is not intended to limit this application. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application should be included within the scope of protection of this application.

Claims

1. A silicon-based substituted compound, the structural formula of which is shown in general formula (Ⅰ): in, R1-R2 are independently selected from C1-C4 alkyl, C3-C6 cycloalkyl, unsubstituted or Ra-substituted groups of the following: C6-C30 aromatic groups or C5-C30 heteroaryl groups; R 3 -R 6 The R group is independently selected from hydrogen, C1-C4 alkyl, C3-C5 cycloalkyl, C2-C6 alkenyl, hydroxyl, aniline, and the following groups, either unsubstituted or substituted with Ra: amino, C6-C30 aromatic, or C5-C30 heteroaryl, wherein the R group is... 3 -R 6 Two adjacent groups can connect to form a ring; R 7 -R 9 The R group is independently selected from hydrogen, C1-C4 alkyl, C3-C5 cycloalkyl, C2-C6 alkenyl, unsubstituted or Ra-substituted groups of the following: amino, C6-C30 aryl, or C5-C30 heteroaryl, wherein the R group is... 7 -R 9 Two adjacent groups can connect to form a ring; L1 is selected from chemical bonds, C6-C30 aromatic groups, or C5-C30 heteroaryl groups; L2 is selected from chemical bonds, C6-C30 aromatic alkyl groups, or C5-C30 heteroaryl groups; Ar is selected from the following groups, either unsubstituted or substituted by Ra: aromatic groups of C6-C30, heteroaryl groups of C5-C30, or aromatic amino groups; The heteroatoms on the heteroaryl group or the heteroalkylene group are each independently selected from O, S or N; The Ra is independently selected from deuterium, nitro, cyano, C1-C4 alkyl, C5-C20 cycloalkyl, phenyl, biphenyl, terphenyl, naphthyl, phenylsilyl or benzocyclohexyl.

2. The silicon-based substituted compound according to claim 1, wherein, R1-R2 are independently selected from C1-C4 alkyl, C3-C6 cycloalkyl, unsubstituted or Ra-substituted groups of the following: C6-C18 aromatic or C5-C18 heteroaryl; R 3 -R 6 The R group is independently selected from hydrogen, C1-C4 alkyl, C3-C5 cycloalkyl, C2-C6 alkenyl, hydroxyl, aniline, and the following groups, either unsubstituted or substituted with Ra: amino, C6-C18 aryl, or C6-18 heteroaryl, wherein the R group is... 3 -R 6 Two adjacent groups can connect to form a ring; R 7 -R 9 The R group is independently selected from hydrogen, C1-C4 alkyl, C3-C5 cycloalkyl, C2-C6 alkenyl, unsubstituted or Ra-substituted groups of the following: amino, C6-C18 aryl or C5-C18 heteroaryl, wherein the R group is... 7 -R 9 Two adjacent groups can connect to form a ring; Ar is selected from the following groups, either unsubstituted or substituted by Ra: C6-C18 aromatic groups, C5-C18 heteroaryl groups, or aromatic amino groups; The Ra is independently selected from deuterium, halogen, C1-C4 alkyl, C5-C20 cycloalkyl, phenyl, biphenyl, terphenyl or naphthyl.

3. The silicon-based substituted compound according to claim 1, wherein, R1-R2 are independently selected from methyl, ethyl, isopropyl, tert-butyl, cyclopentyl, cyclohexyl, unsubstituted or Ra-substituted groups of the following: phenyl, biphenyl, naphthyl, phenanthryl, fluorenyl, dibenzofuranyl, dibenzothiopheneyl or carbazoleyl.

4. The silicon-based substituted compound according to claim 1, wherein, R 3 -R 6 The R group is independently selected from hydrogen, methyl, ethyl, isopropyl, tert-butyl, cyclopropyl, cyclopentyl, vinyl, hydroxyl, aniline, and the following groups, either unsubstituted or substituted with Ra: amino, phenyl, biphenyl, terphenyl, naphthyl, phenanthrene, triphenylene, fluorenyl, dibenzofuranyl, dibenzothiophene, 9,9-dimethylfluorenyl, or spirofluorenyl. 3 -R 6 Two adjacent groups can connect to form a ring.

5. The silicon-based substituted compound according to claim 1, wherein, R 7 -R 9 The R group is independently selected from hydrogen, methyl, ethyl, isopropyl, tert-butyl, cyclopropyl, cyclopentyl, vinyl, unsubstituted or Ra-substituted groups of the following: amino, phenyl, biphenyl, terphenyl, naphthyl, phenanthrene, triphenylene, fluorenyl, dibenzofuranyl, dibenzothiophene, 9,9-dimethylfluorenyl or spirofluorenyl, wherein the R group is... 7 -R 9 Two adjacent groups can connect to form a ring.

6. The silicon-based substituted compound according to claim 1, wherein, Ar is selected from the following groups, either unsubstituted or substituted by Ra: phenyl, biphenyl, terphenyl, naphthyl, phenanthrene, triphenylene, fluorenyl, biphenylamino, benzofuranyl, dibenzofuranyl, benzothiophene, dibenzothiophene, 9,9-dimethylfluorenyl, phenylfluorenyl, spirofluorenyl, aromatic amino, carbazole, or fluoranthene.

7. The silicon-based substituted compound according to claim 1, wherein, L1 is selected from chemical bonds, phenylene, biphenylene, terphenylene, naphthylene, phenanthrene, terphenylene, fluorene, benzofuranyl, or dibenzofuranyl.

8. The silicon-based substituted compound according to claim 1, wherein, L2 is selected from chemical bonds, phenylene, biphenylene, terphenylene, naphthylene, phenanthroline, terphenylene, fluorene, benzofuranyl, or dibenzofuranyl.

9. The silicon-based substituted compound according to claim 1, wherein, The silicon-based substituted compound is selected from the compounds shown in A1-A55 below:

10. A hole transport material comprising at least one of the silicon-based substituted compounds according to any one of claims 1-9.

11. An organic electroluminescent device comprising at least one of the hole transport materials of claim 10.

12. A display device comprising the organic electroluminescent device of claim 11.

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