Cyanosubstituted aryl ring connected triazine compounds and uses thereof

Abstract

The application relates to the technical field of organic light-emitting display, and discloses a cyano-substituted aryl ring-connected triazine compound and application thereof. The cyano-substituted aryl ring-connected triazine compound has a structure as shown in formula (I), the compound provided by the application has high bond energy between atoms, good thermal stability, is conducive to solid-state stacking between molecules, is conducive to injection and migration of excitons, can effectively reduce the driving voltage of an organic electroluminescent device when used as an electron transport material, improves the light-emitting efficiency of the organic electroluminescent device, and prolongs the service life of the organic electroluminescent device. Meanwhile, the cyano substitution can adjust the energy level of the compound, the HOMO and LUMO energy levels are deepened, the compound is more matched with adjacent layers, and the device voltage is reduced. The application further provides an organic electroluminescent device and a display device containing the compound of formula (I).

Description

Technical Field

[0001] This invention relates to the field of organic light-emitting display technology, and in particular to a cyano-substituted aromatic triazine compound and its applications. Background Technology

[0002] Electroluminescence (EL) refers to the phenomenon where a luminescent material emits light when excited by an electric field and subjected to current and voltage. 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 the fields of lighting and display, people are paying more attention to the research on high-efficiency organic materials that affect the performance of OLED devices. An efficient and long-life organic electroluminescent device is usually the result of the optimized combination of device structure and various organic materials, which provides great opportunities and challenges for those skilled in the art to design and develop functional materials with various structures.

[0004] Compared to inorganic light-emitting materials, organic electroluminescent materials have many advantages, such as: good processing performance (they can be deposited on any substrate through evaporation or spin coating), the ability to achieve flexible and large-area displays, and the ability to adjust the optical, electrical, and stability properties of the materials by modifying their molecular structure, offering a wide range of material choices. The most common OLED device structures typically include the following types of organic materials: hole injection materials, hole transport materials, electron transport materials, and light-emitting materials (including host and guest materials). Currently, electron transport materials, as an important functional material, directly affect electron mobility and ultimately the luminous efficiency of OLEDs. The low mobility of currently commercially available electron transport materials is a significant limiting factor in the development of device performance, and further exploration is warranted to develop materials with higher mobility. Summary of the Invention

[0005] The purpose of this invention is to provide a compound that, when used as an electron transport material, can improve the working efficiency and extend the lifespan of organic electroluminescent devices.

[0006] The first aspect of this invention aims to provide a cyano-substituted aromatic ring triazine compound having the structure shown in formula (I):

[0007]

[0008] Ar1 and Ar2 are each independently selected from unsubstituted or Rc-substituted C6-C. 30 Aryl, unsubstituted or Rc-substituted C3-C 30 Mixed aromatics;

[0009] L is selected from chemical bonds, unsubstituted or Rc-substituted C6-C. 30 aryl, unsubstituted or Rc-substituted C3-C 30 heteroaryl;

[0010] A is selected from the following structures that are unsubstituted or substituted by Rc:

[0011]

[0012] The heteroatoms on the heteroaryl group or the heteroaryl group are each independently selected from O, S, and N;

[0013] The substituents Rc of each group are independently selected from deuterium, halogen, nitro, cyano, C1-C4 alkyl, phenyl, biphenyl, terphenyl or naphthyl.

[0014] Preferably, the cyano-substituted aromatic ring triazine compound is selected from the following general formula structures:

[0015]

[0016] Preferably, Ar1 and Ar2 are each independently selected from the subunits of the following compounds that are unsubstituted or Rc-substituted: benzene, biphenyl, terphenyl, naphthalene, phenanthrene, triphenylene, fluorene, pyridine, pyridazine, pyrimidine, pyrazine, quinoline, isoquinoline, quinazoline, quinoxaline, cyclophosphine, triazine, pyridopyrazine, benzofuran, dibenzofuran, aza-dibenzofuran, dibenzothiophene, aza-dibenzothiophene, 9,9-dimethylfluorene, and spirofluorene.

[0017] Preferably, L is selected from the subunits of the following compounds that are chemically bonded, unsubstituted, or Rc-substituted: benzene, biphenyl, terphenyl, naphthalene, phenanthrene, triphenylene, fluorene, pyridine, pyridazine, pyrimidine, pyrazine, quinoline, isoquinoline, quinazoline, quinoxaline, cyclophosphine, triazine, pyridopyrazine, benzofuran, dibenzofuran, aza-dibenzofuran, benzothiophene, dibenzothiophene, aza-dibenzothiophene, 9,9-dimethylfluorene, spirofluorene, and phenylcyano.

[0018] More preferably, the cyano-substituted aryl triazine compound is selected from the compounds shown in A1 to A32 below:

[0019]

[0020]

[0021]

[0022] A second aspect of the present invention aims to provide an electron transport material comprising at least one of the compounds provided in the first aspect of the present invention.

[0023] A third aspect of the present invention aims to provide an organic electroluminescent device comprising at least one of the electron transport materials provided in the second aspect of the present invention.

[0024] A fourth aspect of the present invention is to provide a display device comprising the organic electroluminescent device provided in the third aspect of the present invention.

[0025] Compared with existing technologies, the beneficial effects of this invention are as follows: The compound provided by this invention has a parent structure of cyano-substituted triazine, with high interatomic bond energy, good thermal stability, and favorable solid-state packing between molecules. When used as an electron transport material, the introduction of the cyano group can deepen the HOMO energy level of the material, achieving a suitable energy level with the adjacent cathode, which is beneficial for the injection and migration of electrons from the cathode to the electron transport layer, effectively reducing the driving voltage. Simultaneously, it exhibits a high electron mobility rate, enabling good luminous efficiency and lifespan in organic electroluminescent devices. Furthermore, the introduction of the cyano group in the compound enhances the binding force between electrons and the material, increasing electron affinity and ultimately improving efficiency in the device. The compound of this invention possesses a large conjugated plane, which is beneficial for molecular packing, exhibiting good thermodynamic stability and long lifespan in the device. The organic electroluminescent device of this invention, containing the compound as an electron transport material, can effectively reduce the driving voltage, improve luminous efficiency, and extend the lifespan of the organic electroluminescent device. The display device provided by this invention has excellent display effects.

[0026] Of course, implementing any product or method of the present invention does not necessarily require achieving all of the advantages described above at the same time. Attached Figure Description

[0027] To more clearly illustrate the technical solutions in this invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this invention. For those skilled in the art, other embodiments can be obtained based on these drawings.

[0028] Figure 1This is a schematic diagram of a typical organic electroluminescent device. Reference numerals: 1. Substrate; 2. Reflective anode electrode; 3. Hole injection layer; 4. Hole transport layer; 5. Emitting layer; 6. Electron transport layer; 7. Electron injection layer; 8. Cathode electrode. Detailed Implementation

[0029] The technical solutions of this invention will now be clearly and completely described with reference to the accompanying drawings. Obviously, the described embodiments are merely a part of the embodiments of this invention, and not all of them. All other embodiments obtained by those skilled in the art based on the embodiments of this invention are within the scope of protection of this invention.

[0030] The first aspect of this invention provides a cyano-substituted aromatic ring triazine compound having the structure shown in formula (I):

[0031]

[0032] Ar1 and Ar2 are each independently selected from unsubstituted or Rc-substituted C6-C. 30 Aryl, unsubstituted or Rc-substituted C3-C 30 Mixed aromatics;

[0033] L is selected from chemical bonds, unsubstituted or Rc-substituted C6-C. 30 aryl, unsubstituted or Rc-substituted C3-C 30 heteroaryl;

[0034] A is selected from the following structures that are unsubstituted or substituted by Rc:

[0035]

[0036] The heteroatoms on the heteroaryl group or the heteroaryl group are each independently selected from O, S, and N;

[0037] The substituents Rc of each group are independently selected from deuterium, halogen, nitro, cyano, C1-C4 alkyl, phenyl, biphenyl, terphenyl or naphthyl.

[0038] Preferably, the cyano-substituted aromatic ring triazine compound is selected from the following general formula structures:

[0039]

[0040] In a preferred embodiment, Ar1 and Ar2 are each independently selected from the subunits of the following compounds that are unsubstituted or Rc-substituted: benzene, biphenyl, terphenyl, naphthalene, phenanthrene, triphenylene, fluorene, pyridine, pyridazine, pyrimidine, pyrazine, quinoline, isoquinoline, quinazoline, quinoxaline, cyclophosphine, triazine, pyridopyrazine, benzofuran, dibenzofuran, aza-dibenzofuran, dibenzothiophene, aza-dibenzothiophene, 9,9-dimethylfluorene, and spirofluorene.

[0041] In a preferred embodiment, L is selected from the subunits of the following compounds that are chemically bonded, unsubstituted, or Rc-substituted: benzene, biphenyl, terphenyl, naphthalene, phenanthrene, triphenylene, fluorene, pyridine, pyridazine, pyrimidine, pyrazine, quinoline, isoquinoline, quinazoline, quinoxaline, naphthidine, triazine, pyridopyrazine, benzofuran, dibenzofuran, aza-dibenzofuran, benzothiophene, dibenzothiophene, aza-dibenzothiophene, 9,9-dimethylfluorene, spirofluorene, and phenylcyano.

[0042] As a preferred embodiment, the cyano-substituted aromatic ring triazine compound is selected from the compounds shown in A1 to A32 below:

[0043]

[0044]

[0045] A second aspect of the present invention provides an electron transport material comprising at least one of the compounds provided in the first aspect of the present invention.

[0046] A third aspect of the present invention aims to provide an organic electroluminescent device comprising at least one of the electron transport materials provided in the second aspect of the present invention.

[0047] In this invention, there are no particular limitations 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 electron transport material provided by this invention can be used.

[0048] The organic electroluminescent device of the present invention can be a top-emitting structure, which can sequentially include an anode, a hole injection layer, a hole transport layer, an emitting layer, an electron transport layer, an electron injection layer, and a transparent or semi-transparent cathode on a substrate.

[0049] The organic electroluminescent device of the present invention can also be a bottom-emitting device, which can sequentially include 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 on a substrate.

[0050] The organic electroluminescent device of the present invention can also be a light-emitting device with a dual-sided light-emitting structure, which can be exemplified by 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 sequentially included on a substrate.

[0051] In addition, an electron blocking layer may be provided between the hole transport layer and the light-emitting layer, and a hole blocking layer may be provided between the light-emitting layer and the electron transport layer. A light extraction layer may be provided on the transparent electrode on the light-emitting side. However, the structure of the organic electroluminescent device of the present invention is not limited to the specific structure described above. If necessary, the above-mentioned layers may be omitted or added. The present invention does not impose any particular limitation on the thickness of the above-mentioned layers, as long as the purpose of the present invention can be achieved. For example, the organic electroluminescent device may sequentially include an anode made of metal, 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 (150nm to 400nm), a hole blocking layer (5nm to 20nm), an electron transport layer (300nm to 800nm), an electron injection layer (5nm to 20nm), a transparent or semi-transparent cathode, and a light extraction layer (50nm to 90nm) on a substrate.

[0052] 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.

[0053] Understandable. Figure 1 The structure of a typical organic electroluminescent device is shown only schematically. The present invention is not limited to this structure, and the electron transport material of the present invention can be used in any type of organic electroluminescent device.

[0054] For convenience, the following references Figure 1 The organic electroluminescent device of the present invention will be described, but this does not imply any limitation on the scope of protection of the present invention. It is understood that all organic electroluminescent devices that can use the electron transport material of the present invention are within the scope of protection of the present invention.

[0055] In this invention, the substrate 1 is not particularly limited and can be a 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.

[0056] In this invention, the reflective anode material 2 is not particularly limited and 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), and zinc oxide (ZnO), or metallic materials such as silver and its alloys, aluminum and its alloys, or organic conductive materials such as poly(3,4-ethylenedioxythiophene) (PEDOT), or multilayer structures of the above materials.

[0057] In this invention, the material of the hole injection layer 3 is not particularly limited and can be made of hole injection layer materials known in the art. For example, at least one of the known hole transport materials (HTM) can be selected as the hole injection material.

[0058] In this invention, 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, but is not limited to, at least one of the following p-1 to p-3 compounds:

[0059]

[0060] In this invention, the amount of p-type dopant used is not particularly limited and can be any amount known to those skilled in the art.

[0061] In this invention, the material of the hole transport layer 4 is not particularly limited and can be made of hole transport materials (HTM) known in the art. The number of layers of the hole transport layer 4 is not particularly limited and can be adjusted according to actual needs, as long as the purpose of this invention is met, for example, 1 layer, 2 layers, 3 layers, 4 layers or more.

[0062] For example, HTM for hole injection layer materials and HTM for hole transport layer materials can be selected from, but are not limited to, at least one of the following HT-1 to HT-31 compounds:

[0063]

[0064]

[0065] In this invention, the light-emitting layer 5 may include a blue light-emitting layer, a green light-emitting layer, or a red light-emitting layer. There are no particular limitations on the light-emitting material in the light-emitting layer 5, and various light-emitting materials known to those skilled in the art can be used. For example, the material of the light-emitting layer 5 may include a host material and a guest material.

[0066] In this invention, the host material may be selected from, but is not limited to, at least one of the following BH-1 to BH-10 compounds:

[0067]

[0068] In this invention, the guest material is not particularly limited, 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:

[0069]

[0070] In this invention, there is no particular limitation on the amount of guest material used in the light-emitting layer, and it can be any amount known to those skilled in the art.

[0071] In this invention, the electron transport layer 6 comprises at least one of the electron transport materials of this invention, or it may comprise a combination of at least one of the electron transport materials of this invention and at least one of known electron transport materials. The number of layers in the electron transport layer 6 is not particularly limited and can be adjusted according to actual needs, as long as the purpose of this invention is met; for example, one, two, three, four, or more layers.

[0072] For example, it is known that electron transport materials can be selected from, but are not limited to, at least one of the following ET-1 to ET-57 compounds:

[0073]

[0074]

[0075]

[0076] In this invention, 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, such as the following n-type dopants:

[0077]

[0078] In this invention, the amount of the n-type dopant is not particularly limited and can be any amount known to those skilled in the art.

[0079] In this invention, the material of the electron injection layer 7 is not particularly limited, and electron injection materials known in the art can be used. For example, it can include, but is not limited to, at least one of the following materials in the prior art: LiQ, LiF, NaCl, CsF, Li2O, Cs2CO3, BaO, Na, Li, Ca, etc.

[0080] In this invention, the material of the cathode electrode 8 is not particularly limited and 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.

[0081] A fourth aspect of the present invention provides a display device comprising the organic electroluminescent device provided in the third aspect of the present invention. The display device includes, but is not limited to, a monitor, a television, a tablet computer, a mobile communication terminal, etc.

[0082] There are no particular limitations on the method for preparing the organic electroluminescent device of the present invention, and any method known in the art can be used. For example, the present invention can be prepared by the following method:

[0083] (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.

[0084] (2) Hole injection material is vacuum-deposited on the reflective anode electrode 2 as a hole injection layer 3;

[0085] (3) Hole transport material is vacuum-deposited on hole injection layer 3 as hole transport layer 4;

[0086] (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;

[0087] (5) Electron transport material is vacuum-deposited on the light-emitting layer 5 as electron transport layer 6;

[0088] (6) Vacuum evaporation of electron injection material on electron transport layer 6 to serve as electron injection layer 7;

[0089] (7) Vacuum evaporation of cathode material on electron injection layer 7 as cathode electrode 8.

[0090] The above describes only a typical structure and fabrication method of an organic electroluminescent device. It should be understood that the present invention is not limited to this structure. The electron transport material of the present invention 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.

[0091] The synthesis method of the compounds 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 examples illustrate the synthesis process of the compounds of the present invention.

[0092] Synthesis Example 1: Synthesis of Compound A2:

[0093]

[0094] 100 mmol of 3-bromo-6-chlorobenzonitrile, 100 mmol of 1-naphthylboronic 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, along with 1 mol% of tetra(triphenylphosphine)palladium (Pd(PPh3)4). The reaction was carried out at 60 °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(PPh3)4 added was 1 mol% of 3-bromo-6-chlorobenzonitrile.

[0095] 100 mmol of M1, 100 mmol of pinacol diborate, 41.4 g of potassium carbonate (300 mmol), and 800 ml of dioxane were added to a reaction flask, along with 1 mol% of tetra(triphenylphosphine)palladium (Pd(PPh3)4). The reaction was carried out at 100 °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(PPh3)4 added was 1 mol% of M1.

[0096] 100 mmol of p-chlorobromobenzene, 100 mmol of 2-naphthylboronic 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, along with 1 mol% of tetra(triphenylphosphine)palladium (Pd(PPh3)4). The reaction was carried out at 60 °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(PPh3)4 added was 1 mol% of the p-chlorobromobenzene.

[0097] 100 mmol of M3, 100 mmol of pinacol diborate, 41.4 g of potassium carbonate (300 mmol), and 800 ml of dioxane were added to a reaction flask, along with 1 mol% of tetra(triphenylphosphine)palladium (Pd(PPh3)4). The reaction was carried out at 100 °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(PPh3)4 added was 1 mol% of M3.

[0098] 100 mmol of 2,4-dichloro-6-phenyltriazine, 100 mmol of M4, 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 mol% of tetra(triphenylphosphine)palladium (Pd(PPh3)4). The reaction was carried out at 60 °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(PPh3)4 added was 1 mol% of 2,4-dichloro-6-phenyltriazine.

[0099] 100 mmol of M2, 100 mmol of M5, 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 mol% of tetra(triphenylphosphine)palladium (Pd(PPh3)4). The reaction was carried out at 60 °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(PPh3)4 added was 1 mol% of M2.

[0100] 1 H NMR (400MHz, Chloroform) δ8.94(d,J=7.2Hz,1H),8.52(d,J=7.2Hz,1H),8.36(d,J=7.6Hz,2H),8.24(s,1H),8.14(d,J=8.0Hz,1H),8.06(t,J=7.6Hz,2H) ,8.00(d,J=7.2Hz,1H),7.92(d,J=8.4Hz,2H),7.84(d,J=7.2Hz,1H),7.76(d ,J=7.6Hz,2H),7.65-7.48(m,7H),7.45-7.30(m,3H),7.20(d,J=8.4Hz,2H).

[0101] Synthesis Example 2: Synthesis of Compound A3:

[0102]

[0103] 100 mmol of 2,4-dichloro-6-phenyltriazine, 100 mmol of 4-biphenylboronic 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, along with 1 mol% of tetra(triphenylphosphine)palladium (Pd(PPh3)4). The reaction was carried out at 60 °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(PPh3)4 added was 1 mol% of 2,4-dichloro-6-phenyltriazine.

[0104] 100 mmol of 4-bromo-5-chlorobenzonitrile, 100 mmol of 2-naphthylboronic 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, along with 1 mol% of tetra(triphenylphosphine)palladium (Pd(PPh3)4). The reaction was carried out at 60 °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(PPh3)4 added was 1 mol% of 4-bromo-5-chlorobenzonitrile.

[0105] 100 mmol of M2, 100 mmol of pinacol diborate, 41.4 g of potassium carbonate (300 mmol), and 800 ml of dioxane were added to a reaction flask, along with 1 mol% 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, 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(PPh3)4 added was 1 mol% of M2.

[0106] 100 mmol of M1, 100 mmol of M3, 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 mol% of tetra(triphenylphosphine)palladium (Pd(PPh3)4). The reaction was carried out at 60 °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 A3. The amount of Pd(PPh3)4 added was 1 mol% of M1.

[0107] 1H NMR (400MHz, Chloroform) δ8.40-8.32(m,3H),8.14(d,J=8.8Hz,1H),8.10(d,J=7.2Hz,1H),8.06(d,J=6.8Hz,1H),8.00(t,J=7.2Hz,2H ),7.92(d,J=8.8Hz,2H),7.76(d,J=8.0Hz,2H),7.64-7.46(m,8H),7.42(d,J=6.8Hz,1H),7.36(d,J=6.8Hz,1H),7.24(d,J=8.8Hz,2H).

[0108] Synthesis Example 3: Synthesis of Compound A12:

[0109]

[0110] 100 mmol of 2,4-dichloro-6-phenyltriazine, 100 mmol of 9-phenanthroline, 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 mol% of tetra(triphenylphosphine)palladium (Pd(PPh3)4). The reaction was carried out at 60 °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(PPh3)4 added was 1 mol% of 2,4-dichloro-6-phenyltriazine.

[0111] 100 mmol of M1, 100 mmol of p-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, along with 1 mol% of tetra(triphenylphosphine)palladium (Pd(PPh3)4). The reaction was carried out at 60 °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(PPh3)4 added was 1 mol% of M1.

[0112] 100 mmol of 3-bromo-5-chlorobenzonitrile, 100 mmol of 2-naphthylboronic 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, along with 1 mol% of tetra(triphenylphosphine)palladium (Pd(PPh3)4). The reaction was carried out at 60 °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(PPh3)4 added was 1 mol% of 3-bromo-5-chlorobenzonitrile.

[0113] 100 mmol of M3, 100 mmol of pinacol diborate, 41.4 g of potassium carbonate (300 mmol), and 800 ml of dioxane were added to a reaction flask, along with 1 mol% of tetra(triphenylphosphine)palladium (Pd(PPh3)4). The reaction was carried out at 100 °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(PPh3)4 added was 1 mol% of M3.

[0114] 100 mmol of M2, 100 mmol of M4, 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 mol% of tetra(triphenylphosphine)palladium (Pd(PPh3)4). The reaction was carried out at 60 °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(PPh3)4 added was 1 mol% of M2.

[0115] 1 H NMR (400MHz, Chloroform) δ9.08(d,J=7.2Hz,1H),8.84(d,J=7.2Hz,1H),8.42-8.35(m,4H),8.20(d,J=6.8Hz,2H),8.14(d,J=7.2Hz,2H),8.08(t,J =7.2Hz,1H),8.00(d,J=6.8Hz,1H),7.92(d,J=8.8Hz,2H),7.84(d,J=6.8 Hz,1H),7.74-7.46(m,10H),7.36(d,J=6.8Hz,1H),7.24(d,J=8.8Hz,2H).

[0116] Synthesis Example 4: Synthesis of Compound A17:

[0117]

[0118] 100 mmol of 2-(3-bromophenyl)-4,6-diphenyltriazine, 100 mmol of pinacol diborate, 41.4 g of potassium carbonate (300 mmol), and 800 ml of dioxane were added to a reaction flask, along with 1 mol% 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, 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(PPh3)4 added was 1 mol% of 2-(3-bromophenyl)-4,6-diphenyltriazine.

[0119] 100 mmol of 1,3-dibromo-5-chlorobenzene, 200 mmol of pyridine-3-boric 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, along with 2 mol% tetra(triphenylphosphine)palladium (Pd(PPh3)4). The reaction was carried out at 60 °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(PPh3)4 added was 2 mol% of 1,3-dibromo-5-chlorobenzene.

[0120] 100 mmol of M2, 100 mmol of pinacol diborate, 41.4 g of potassium carbonate (300 mmol), and 800 ml of dioxane were added to a reaction flask, along with 1 mol% 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, 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(PPh3)4 added was 1 mol% of M2.

[0121] 100 mmol of 2-bromo-5-chlorobenzonitrile, 100 mmol of M3, 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 mol% of tetra(triphenylphosphine)palladium (Pd(PPh3)4). The reaction was carried out at 60 °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(PPh3)4 added was 1 mol% of 2-bromo-5-chlorobenzonitrile.

[0122] 100 mmol of M1, 100 mmol of M4, 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 mol% of tetra(triphenylphosphine)palladium (Pd(PPh3)4). The reaction was carried out at 60 °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(PPh3)4 added was 1 mol% of M1.

[0123] 1 H NMR (400MHz, Chloroform) δ9.24 (s, 2H), 8.70 (d, J = 7.2Hz, 2H), 8.41-8.30 (m, 8H), 8.26 (d, J = 8. 0Hz,1H),8.14(t,J=7.2Hz,4H),7.72(t,J=2.6Hz,1H),7.60(d,J=6.8Hz,1H),7.58-7.42(m,9H).

[0124] Synthesis Example 5: Synthesis of Compound A27:

[0125]

[0126] 100 mmol of 3,5-dicyanobromobenzene, 100 mmol of pinacol diborate, 41.4 g of potassium carbonate (300 mmol), and 800 ml of dioxane were added to a reaction flask, along with 1 mol% 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, 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(PPh3)4 added was 1 mol% of 3,5-dicyanobromobenzene.

[0127] 100 mmol of 2,4-dichloro-6-phenyltriazine, 100 mmol of M1, 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 mol% of tetra(triphenylphosphine)palladium (Pd(PPh3)4). The reaction was carried out at 60 °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(PPh3)4 added was 1 mol% of 2,4-dichloro-6-phenyltriazine.

[0128] 100 mmol of M2, 100 mmol of 3-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, along with 1 mol% of tetra(triphenylphosphine)palladium (Pd(PPh3)4). The reaction was carried out at 60 °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(PPh3)4 added was 1 mol% of M2.

[0129] 100 mmol of 4-bromo-5-chlorobenzonitrile, 100 mmol of 1-naphthylboronic 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, along with 1 mol% of tetra(triphenylphosphine)palladium (Pd(PPh3)4). The reaction was carried out at 60 °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(PPh3)4 added was 1 mol% of 4-bromo-5-chlorobenzonitrile.

[0130] 100 mmol of M4, 100 mmol of pinacol diborate, 41.4 g of potassium carbonate (300 mmol), and 800 ml of dioxane were added to a reaction flask, along with 1 mol% of tetra(triphenylphosphine)palladium (Pd(PPh3)4). The reaction was carried out at 100 °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(PPh3)4 added was 1 mol% of M4.

[0131] 100 mmol of M3, 100 mmol of M5, 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 mol% of tetra(triphenylphosphine)palladium (Pd(PPh3)4). The reaction was carried out at 60 °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, A27. The amount of Pd(PPh3)4 added was 1 mol% of M3.

[0132] 1H NMR(400MHz,Chloroform)δ8.94(d,J=7.2Hz,1H),8.58(s,2H),8.50(d,J=7.2H z,1H),8.42-8.33(m,3H),8.22(d,J=7.2Hz,2H),8.14(d,J=8.0Hz,1H),8.08(s, 1H),8.04(d,J=7.2Hz,1H),7.92(d,J=7.2Hz,1H),7.80(d,J=7.2Hz,2H),7.70(t ,J=7.2Hz,1H),7.64(d,J=7.2Hz,1H),7.54-7.46(m,3H),7.36(t,J=7.2Hz,2H).

[0133] Other compounds of the present invention can be synthesized by selecting suitable raw materials according to the ideas of the above-described synthesis examples 1-5, or by selecting any other suitable methods and raw materials.

[0134] Example 1

[0135] The glass substrate 1 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.

[0136] Then, the glass substrate 1 with the reflective anode electrode 2 is placed in a vacuum chamber and evacuated to a vacuum level of less than 10. -5 A hole injection layer 3 is vacuum-deposited on the aforementioned anolyte film. The hole injection layer 3 is made of hole injection layer material HT-11 and p-type dopant p-1. The deposition is performed using a multi-source co-evaporation method. The deposition rate of hole injection layer material HT-11 is adjusted to 0.1 nm / s, and the deposition rate of p-type dopant p-1 is 3% of the deposition rate of hole injection layer material HT-11. The deposited film thickness is 10 nm. The hole injection layer material HT-11 and p-type dopant p-1 are as follows:

[0137]

[0138] Then, hole transport material HT-3 is vacuum-deposited on hole injection layer 3 as hole transport layer 4, wherein the deposition rate is 0.1 nm / s, the deposition film thickness is 80 nm, and the hole transport material HT-3 is as follows:

[0139]

[0140] Then, a light-emitting layer 5 is vacuum-deposited on the hole transport layer 4. The light-emitting layer 5 includes a host material BH-6 and a fluorescent dopant BD-6, and is deposited using a multi-source co-evaporation method. The evaporation rate of the host material BH-2 is adjusted to 0.1 nm / s, and the evaporation rate of the fluorescent dopant BD-6 is 3% of the evaporation rate of the host material BH-6. The deposited film thickness is 30 nm. The host material BH-6 and the fluorescent dopant BD-6 are as follows:

[0141]

[0142] Then, an electron transport layer 6 is vacuum-deposited on top of the light-emitting layer 5. The electron transport material is compound A2, with a deposition rate of 0.1 nm / s and a film thickness of 30 nm. The electron transport material A2 is as follows:

[0143]

[0144] Then, a 0.5 nm thick LiF layer is vacuum-deposited on the electron transport layer 6 as an electron injection layer 7, wherein the deposition rate is 0.1 nm / s;

[0145] Finally, an Al layer with a thickness of 150 nm is vacuum-deposited on the electron injection layer 7 as the cathode electrode 8 of the organic electroluminescent device, wherein the deposition rate is 0.1 nm / s.

[0146] Examples 2-5

[0147] Except that the electron transport materials are replaced by A3, A12, A17, and A27 respectively instead of A2, everything else is the same as in Example 1.

[0148] Comparative Example 1

[0149] Except for the use of ET-14 as the electron transport material, everything else is the same as in Example 1; ET-14 is as follows:

[0150]

[0151] Comparative Example 2

[0152] Except for the use of ET-R as the electron transport material, everything else is the same as in Example 1; ET-R is as follows:

[0153]

[0154] The organic electroluminescent devices prepared by the above process were subjected to the following performance measurements:

[0155] Under the same brightness, the driving voltage, current efficiency, and lifetime of the organic electroluminescent devices prepared in Examples 1-5 and Comparative Examples 1-2 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 life test of LT95 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 expressed in hours. The results are shown in Table 1.

[0156] Table 1. Performance results of organic electroluminescent devices

[0157]

[0158]

[0159] As can be seen from Table 1, the compounds A2, A3, A12, A17, and A27 prepared in this invention, when used as electron transport materials in organic electroluminescent devices, can effectively reduce driving voltage, improve current efficiency, and extend device lifespan. The materials of this invention have significant performance improvements, especially in improving efficiency and extending lifespan, and are high-performance electron transport materials.

[0160] The above description is merely a preferred embodiment of the present invention and is not intended to limit the scope of protection of the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention are included within the scope of protection of the present invention.

Claims

1. A cyano-substituted aromatic ring triazine compound, characterized in that, It has a structure as shown in equation (I): Ar1 and Ar2 are each independently selected from unsubstituted or Rc-substituted C6-C. 30 Aryl, unsubstituted or Rc-substituted C3-C 30 Mixed aromatics; L is selected from chemical bonds, unsubstituted or Rc-substituted C6-C. 30 aryl, unsubstituted or Rc-substituted C3-C 30 heteroaryl; A is selected from the following structures that are unsubstituted or substituted by Rc: The heteroatoms on the heteroaryl group or the heteroaryl group are each independently selected from O, S, and N; The substituents Rc of each group are independently selected from deuterium, halogen, nitro, cyano, C1-C4 alkyl, phenyl, biphenyl, terphenyl or naphthyl.

2. The cyano-substituted aromatic ring triazine compound according to claim 1, characterized in that, Selected from the following general formula structures:

3. The cyano-substituted aromatic ring triazine compound according to claim 1, characterized in that, Ar1 and Ar2 are each independently selected from the subunits of the following compounds that are unsubstituted or Rc-substituted: benzene, biphenyl, terphenyl, naphthalene, phenanthrene, triphenylene, fluorene, pyridine, pyridazine, pyrimidine, pyrazine, quinoline, isoquinoline, quinazoline, quinoxaline, cyclophosphine, triazine, pyridopyrazine, benzofuran, dibenzofuran, aza-dibenzofuran, dibenzothiophene, aza-dibenzothiophene, 9,9-dimethylfluorene, and spirofluorene.

4. The cyano-substituted aromatic ring triazine compound according to claim 1, characterized in that, The L is selected from the subunits of the following compounds that are chemically bonded, unsubstituted, or Rc-substituted: benzene, biphenyl, terphenyl, naphthalene, phenanthrene, triphenylene, fluorene, pyridine, pyridazine, pyrimidine, pyrazine, quinoline, isoquinoline, quinazoline, quinoxaline, naphthidine, triazine, pyridopyrazine, benzofuran, dibenzofuran, aza-dibenzofuran, benzothiophene, dibenzothiophene, aza-dibenzothiophene, 9,9-dimethylfluorene, spirofluorene, and phenylcyano.

5. The cyano-substituted aromatic ring triazine compound according to any one of claims 1-4, characterized in that, The compounds are selected from those shown in A1 to A32 below:

6. An electron transport material, characterized in that, It includes at least one of the cyano-substituted aromatic triazine compounds according to any one of claims 1-5.

7. An organic electroluminescent device, characterized in that, It includes at least one of the electron transport materials described in claim 6.

8. A display device, characterized in that, It includes the organic electroluminescent device as described in claim 7.

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