Heterocyclic substituted phenanthroline compound, organic electroluminescent device and display device

Abstract

The invention relates to the technical field of organic light-emitting display, in particular to a heterocyclic substituted phenanthroline compound, an organic light-emitting device and a display device. The invention discloses a heterocyclic ring substituted phenanthroline compound with a structure as shown in a formula (I), and provides an organic electroluminescent device which comprises a charge generation layer, and the material of the charge generation layer comprises the compound as shown in the formula (I). According to the organic light-emitting device provided by the invention, the material of the charge generation layer is the heterocycle-substituted phenanthroline compound, has efficient charge generation capability, can effectively improve the light-emitting efficiency of the organic light-emitting device, has a relatively shallow energy level, and can be better matched with the material of the adjacent layer for use, so that the light-emitting efficiency of the organic light-emitting device is improved. According to the invention, the charge transmission performance of the organic electroluminescent device can be effectively improved, the luminous efficiency of the organic electroluminescent device is improved, the driving voltage of the organic electroluminescent device is reduced, and the service life of the organic electroluminescent device is prolonged.

Description

Technical Field

[0001] The present invention relates to the technical field of organic light-emitting display, and in particular to a heterocyclic substituted phenanthroline compound, an organic electroluminescent device and a display apparatus. Background Art

[0002] Electroluminescence (EL) refers to the phenomenon in which a luminescent material emits light when stimulated by an electric field, current, and voltage. It is a luminescence process that directly converts electrical energy into light. Organic electroluminescent displays (OLEDs) offer a range of advantages, including autonomous illumination, low-voltage DC drive, full solid-state technology, wide viewing angles, lightweight, and simple components and manufacturing processes. Compared to liquid crystal displays (LCDs), OLEDs do not require a backlight, offer a wide viewing angle, and require less power. Their response speed can be up to 1,000 times that of LCDs, yet their manufacturing cost is lower than that of LCDs with equivalent resolution. Therefore, OLEDs hold a broad potential for application.

[0003] With the continuous advancement of OLED technology in the fields of lighting and display, people are paying more attention to the research of high-efficiency organic materials that affect the performance of OLED devices. A high-efficiency and long-life organic electroluminescent device is usually the result of an optimized combination of device structure and various organic materials. This presents great opportunities and challenges for those skilled in the art to design and develop functional materials with various structures. Laminated devices can effectively extend the operating life of devices and have therefore become a research hotspot in recent years. How to develop high-efficiency charge generation layer materials and select matching light-emitting units to improve the luminous efficiency and extend the service life of organic electroluminescent devices has become a technical problem that those skilled in the art need to solve urgently. Summary of the Invention

[0004] The object of the present invention is to provide a heterocyclic substituted phenanthroline compound, an organic electroluminescent device and a display device, so as to improve the luminous efficiency of the organic electroluminescent device and prolong its service life.

[0005] The first aspect of the present invention is to provide a heterocyclic substituted phenanthroline compound having a structure as shown in formula (I):

[0006]

[0007] in,

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

[0009] L1 and L2 are each independently selected from a chemical bond, a C6-C 30 Arylene, unsubstituted or Rc-substituted C3-C 30 heteroarylene;

[0010] X1-X4, Y1-Y4 are each independently selected from N or C, and at least one is N;

[0011] The heteroatoms on the heteroaryl group and the heteroarylene group are each independently selected from O, S or N;

[0012] The substituents Rc of each group are each independently selected from hydrogen, deuterium, halogen, nitro, cyano, C1-C4 alkyl, phenyl, biphenyl, terphenyl, pyridyl, pyrimidinyl or naphthyl.

[0013] Preferably, Ar1 and Ar2 are each independently selected from C6-C 18 Aryl, unsubstituted or Rc-substituted C3-C 18 heteroaryl; and / or,

[0014] L1 and L2 are each independently selected from a chemical bond, a C6-C 18 Arylene, unsubstituted or Rc-substituted C3-C 30 Heteroarylene.

[0015] Preferably, Ar1 and Ar2 are each independently selected from the following groups which are unsubstituted or substituted by Ra: phenyl, biphenyl, terphenyl, naphthyl, phenanthrenyl, triphenylene, fluorenyl, benzofuranyl, dibenzofuranyl, benzothienyl, dibenzothienyl, 9,9-dimethylfluorenyl, 9,9-diphenylfluorenyl, spirofluorenyl, aromatic amine, and carbazolyl.

[0016] Preferably, L1 and L2 are each independently selected from the group of the following compounds which are chemically bonded, unsubstituted or substituted by Rc: phenyl, pyridyl, pyrimidinyl, quinoxalinyl, quinazoline, biphenyl, terphenyl, naphthyl, phenanthrenyl, triphenylene, fluorenyl, anthracenyl, dibenzofuranyl, dibenzothiophenyl, 9,9-dimethylfluorenyl, 9,9-diphenylfluorenyl, spirofluorenyl.

[0017] More preferably, the heterocyclic substituted phenanthroline compound is selected from the compounds shown in A1-A25:

[0018]

[0019]

[0020] A second object of the present invention is to provide an organic electroluminescent device comprising a charge generation layer and an electron transport layer, wherein the charge generation layer comprises at least one of the compounds of formula (I) above.

[0021] Preferably, the charge generation layer comprises metal Li or Yb, and the mass percentage of the metal Li or Yb is 0.5%-15% based on the mass of the charge generation layer.

[0022] Preferably, the charge generation layer has a thickness of 10 nm to 30 nm.

[0023] Preferably, the thickness of the electron transport layer is 10 nm-40 nm.

[0024] More preferably, the electron transport layer material includes LiQ, and the mass percentage of the LiQ is 30%-70% based on the mass of the electron transport layer.

[0025] A third object of the present invention is to provide a display device comprising the above-mentioned organic electroluminescent device.

[0026] Compared with the prior art, the present invention has the following beneficial effects:

[0027] The organic electroluminescent device provided by the present invention has a charge generation layer material made of a heterocyclic substituted phenanthroline compound. This compound exhibits efficient charge generation, effectively improving the luminous efficiency of the device. Furthermore, it has a shallow energy level, allowing it to be used in conjunction with adjacent layer materials. This effectively enhances the charge transport performance of the device, improving its luminous efficiency, reducing its driving voltage, and extending its service life. The display device provided by the present invention exhibits excellent display effects.

[0028] It should be noted that implementing any product or method of the present invention does not necessarily need to achieve all of the advantages described above at the same time. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] In order to more clearly illustrate the technical solutions of the present invention, the following briefly introduces the drawings required for use in the description of the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other embodiments can also be obtained based on these drawings.

[0030] Figure 1This is a schematic diagram of the structure of a typical organic electroluminescent device. Reference numerals: 20, organic electroluminescent device; 21, substrate; 22, reflective anode; 231, first hole injection layer; 241, first hole transport layer; 251, first light-emitting layer; 261, first electron transport layer; 27, charge generation layer; 232, second hole injection layer; 242, second hole transport layer; 252, second light-emitting layer; 262, second electron transport layer; 28, electron injection layer; 29, cathode. DETAILED DESCRIPTION

[0031] The following will be combined with the accompanying drawings to clearly and completely describe the technical solutions of the present invention. Obviously, the embodiments described are only some embodiments of the present invention, rather than all embodiments. All other embodiments obtained by ordinary technicians in this field based on the present invention are within the scope of protection of the present invention.

[0032] In the present invention, there is no particular limitation on the type and structure of the organic electroluminescent device. It can be any organic electroluminescent device of different types and structures known in the art, as long as at least one of the charge generating materials and at least one of the electron transport materials provided by the present invention can be used.

[0033] In one embodiment of the present invention, an organic electroluminescent device includes an anode and a cathode, m number of light-emitting units stacked between the anode and the cathode, and m-1 number of charge generation layers, wherein the charge generation layer is between two adjacent light-emitting units, and each charge generation layer includes an n-type charge generation layer and a p-type charge generation layer, wherein m is an integer ≥ 2; each light-emitting unit includes at least one light-emitting layer, and the maximum emission wavelength of light emitted in different light-emitting units is different; at least one of the n-type charge generation layers includes at least one of the compounds represented by formula (I) and a metal-containing material, and the metal-containing material includes a metal, a metal complex, or a combination thereof;

[0034] In one embodiment of the present invention, the light-emitting unit in the organic electroluminescent device may include a first light-emitting unit and a second light-emitting unit, and the two light-emitting units may be the same or different; the charge generation layer may be arranged between the first light-emitting unit and the second light-emitting unit, the first light-emitting unit may be arranged between the anode and the charge generation layer, and the second light-emitting unit may be arranged between the charge generation layer and the cathode, the n-type charge generation layer of the charge generation layer may include at least one of the compounds represented by formula (I) and a metal-containing material, and the second light-emitting unit may further include an electron transport layer between the light-emitting layer of the second light-emitting unit and the cathode.

[0035] In one embodiment of the present invention, in an organic electroluminescent device having two light-emitting units, the first light-emitting unit may further include an HT-light-emitting auxiliary layer between the light-emitting layer of the first light-emitting unit and the anode, and the first light-emitting unit may include an electron transport layer.

[0036] In other embodiments of the present invention, the organic electroluminescent device of the present invention may be a light-emitting device with a top-emitting structure, which may include an anode, a first light-emitting unit, a charge generation layer, a second light-emitting unit, an electron injection layer, and a transparent or semi-transparent cathode in sequence on a substrate.

[0037] The organic electroluminescent device of the present invention may also be a bottom-emitting structure light-emitting device, which may include a transparent or semi-transparent anode, a first light-emitting unit, a charge generation layer, a second light-emitting unit, an electron injection layer, and a cathode in sequence on a substrate.

[0038] The organic electroluminescent device of the present invention can also be a light-emitting device with a double-sided light-emitting structure, which can include a transparent or semi-transparent anode, a first light-emitting unit, a charge generation layer, a second light-emitting unit, an electron injection layer, and a transparent or semi-transparent cathode in sequence on a substrate.

[0039] The first light-emitting unit includes a first hole injection layer, a first hole transport layer, a first light-emitting layer and a first electron transport layer arranged in sequence, and the second light-emitting unit includes a second hole injection layer, a second hole transport layer, a second light-emitting layer and a second electron transport layer arranged in sequence.

[0040] In addition, the organic electroluminescent device of the present invention may have an electron blocking layer between the hole transport layer and the light-emitting layer, a hole blocking layer between the light-emitting layer and the electron transport layer, and 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 above-mentioned specific structure. If necessary, the above-mentioned layers can be omitted or added. The present invention has no particular restrictions on the thickness of the above-mentioned anode, hole injection layer, hole transport layer, electron blocking layer, light-emitting layer, hole blocking layer, electron injection layer, cathode and light extraction layer, as long as the purpose of the present invention can be achieved. For example, an organic electroluminescent device may include, on a substrate, an anode (100 nm to 150 nm) made of a metal, a first hole injection layer (5 nm to 20 nm), a first hole transport layer (80 nm to 140 nm), an electron blocking layer (5 nm to 20 nm), a first light-emitting layer (15 nm to 40 nm), a hole blocking layer (5 nm to 20 nm), a first electron transport layer (10 nm to 40 nm), a charge generation layer (10 nm to 30 nm), a second hole injection layer (5 nm to 20 nm), a second hole transport layer (80 nm to 140 nm), a second light-emitting layer (15 nm to 40 nm), a second electron transport layer (10 nm to 40 nm), an electron injection layer (5 nm to 20 nm), a transparent or semi-transparent cathode, and a light extraction layer (50 nm to 90 nm). For example, Figure 1 A schematic diagram of a typical organic electroluminescent device 20 is shown, wherein, from bottom to top, a substrate 21, a reflective anode 22, a first hole injection layer 231, a first hole transport layer 241, a first light-emitting layer 251, a first electron transport layer 261, a charge generation layer 27, a second hole injection layer 232, a second hole transport layer 242, a second light-emitting layer 252, a second electron transport layer 262, an electron injection layer 28, and a cathode electrode 29 are sequentially arranged. It can be understood that Figure 1 The structure of a typical organic electroluminescent device is schematically shown, and the present invention is not limited to this structure. The charge generation layer material or electron transport layer material of the present invention can be used in any type of organic electroluminescent device.

[0041] For convenience, the organic electroluminescent device of the present invention is described below, but this does not mean any limitation on the scope of protection of the present invention. It is understood that all organic electroluminescent devices using the charge generation layer material or electron transport layer material of the present invention are within the scope of protection of the present invention.

[0042] In some embodiments of the present invention, the charge generation layer includes metal Li or Yb, and the mass percentage of the metal Li or Yb is 0.5%-15% based on the mass of the charge generation layer.

[0043] In some embodiments of the present invention, the charge generation layer has a thickness of 10 nm to 30 nm.

[0044] In some embodiments of the present invention, the thickness of the electron transport layer is 10 nm to 40 nm.

[0045] In some embodiments of the present invention, the electron transport layer comprises LiQ, and the mass percentage of the LiQ is 30%-70% based on the mass of the electron transport layer.

[0046] In the present invention, there is no particular limitation on the substrate 21 , and conventional substrates used in organic electroluminescent devices in the prior art may be used, such as glass, polymer materials, and glass and polymer materials with thin film transistor (TFT) components.

[0047] In the present invention, there is no particular restriction on the material of the reflective anode 22. The reflective anode 22 may be selected from transparent conductive materials such as indium tin oxide (ITO), indium zinc oxide (IZO), tin dioxide (SnO2), and zinc oxide (ZnO) known in the prior art, or from metal materials such as silver and its alloys, aluminum and its alloys, or from organic conductive materials such as poly (3,4-ethylenedioxythiophene) (PEDOT), or the reflective anode 22 may be a multilayer structure formed of the above materials. The present invention does not particularly limit the number of layers of the multilayer structure, and the number may be selected according to actual needs, as long as the purpose of the present invention can be met, for example, 1 layer, 2 layers, 3 layers, or more layers.

[0048] In the present invention, there is no particular limitation on the materials of the first hole injection layer 231 and the second hole injection layer 232. Hole injection layer materials known in the art or hole transport layer materials (HTM) known in the art may be used. For example, at least one of the known hole transport layer materials (HTM) may be selected as the hole injection layer material.

[0049] In the present invention, the first hole injection layer 231 and the second hole injection layer 232 may further include a p-type dopant. The present invention has no particular limitation on the type of the p-type dopant, and various p-type dopants known in the art may be used. For example, the p-type dopant may be selected from, but not limited to, at least one of the following compounds p-1 to p-3:

[0050]

[0051] In the present invention, there is no particular limitation on the amount of the p-type dopant, which may be an amount known to those skilled in the art.

[0052] In the present invention, there is no particular limitation on the materials of the first hole transport layer 241 and the second hole transport layer 242, and they can be made of hole transport layer materials (HTM) known in the art. The present invention does not particularly limit the number of hole transport layers and can be adjusted according to actual needs as long as the purpose of the present invention is met, for example, one, two, three, four, or more layers.

[0053] For example, the HTM used as the hole injection layer material and the HTM used as the hole transport layer material may be selected from, but not limited to, at least one of the following HT-1 to HT-31 compounds:

[0054]

[0055]

[0056]

[0057] In the present invention, there is no particular restriction on the materials of the first light-emitting layer 251 and the second light-emitting layer 252, and they may each contain a light-emitting layer host material and a light-emitting layer guest material. There is no particular restriction on the amount of the light-emitting layer host material and the light-emitting layer guest material, and they may be amounts known to those skilled in the art.

[0058] In the present invention, the light-emitting layer may include a blue light-emitting layer, a green light-emitting layer or a red light-emitting layer. The light-emitting material in the light-emitting layer is not particularly limited, and various light-emitting materials known to those skilled in the art can be used.

[0059] In the present invention, there is no particular limitation on the host material of the light-emitting layer, and at least one of the light-emitting layer host materials known in the art can be used. For example, it can be selected from, but not limited to, at least one of the following compounds BH-1 to BH-10:

[0060]

[0061] In the present invention, there is no particular limitation on the guest material for the light-emitting layer, and at least one of the light-emitting layer guest materials known in the art can be used. For example, the light-emitting layer guest material can be selected from, but not limited to, at least one of the following compounds BD-1 to BD-9:

[0062]

[0063] In the present invention, the first electron transport layer 261 and the second electron transport layer 262 comprise at least one of the electron transport layer materials of the present invention, or may comprise a combination of at least one of the electron transport layer materials of the present invention and at least one of known electron transport materials. The number of electron transport layers is not particularly limited and may be adjusted as needed to meet the objectives of the present invention, for example, one, two, three, four, or more layers.

[0064] For example, known electron transport materials may be selected from, but not limited to, at least one of the following ET-1 to ET-57 compounds:

[0065]

[0066]

[0067]

[0068] In the present invention, the first electron transport layer 261 and the second electron transport layer 262 may each further include an n-type dopant. There is no particular limitation on the type of the n-type dopant, and various n-type dopants known in the art may be used. For example, the following n-type dopant, 8-hydroxyquinoline lithium (LiQ), may be used:

[0069]

[0070] In the present invention, there is no particular limitation on the amount of the n-type dopant, which may be an amount known to those skilled in the art.

[0071] In the present invention, the charge generation layer 27 may include at least one of the charge generation layer materials of the present invention, or may include a combination of at least one of the charge generation layer materials of the present invention and at least one of known charge generation materials.

[0072] For example, known charge generating materials may be selected from, but not limited to, at least one of the following CGL00R1 to CGL00R5 compounds:

[0073]

[0074] In the present invention, there is no particular limitation on the material of the electron injection layer 28, and any electron injection layer material known in the art may be used, for example, including but not limited to at least one of the materials in the prior art such as 8-hydroxyquinoline lithium (LiQ), LiF, NaCl, CsF, Li2O, Cs2CO3, BaO, Na, Li, and Ca.

[0075] In the present invention, there is no particular limitation on the material of the cathode electrode 29 , and the material may be selected from, but not limited to, a magnesium-silver mixture, LiF / Al, ITO, Al, or other metals, metal mixtures, oxides, and the like.

[0076] The method for preparing the organic electroluminescent device of the present invention is not particularly limited, and any method known in the art may be used. For example, the present invention may be prepared by the following preparation method:

[0077] The method for preparing the organic electroluminescent device of the present invention may further include but is not limited to the following steps:

[0078] (1) Cleaning the reflective anode 22 on the top-emitting organic electroluminescent device substrate 21 by using a cleaning machine through steps such as chemical cleaning, water cleaning, brush cleaning, high-pressure water cleaning, and air knife cleaning, and then heating treatment;

[0079] (2) vacuum evaporating a hole injection material on the reflective anode 22 to form a first hole injection layer 231;

[0080] (3) vacuum evaporating a hole transport layer material on the first hole injection layer 231 to form the first hole transport layer 241;

[0081] (4) vacuum evaporating a first light-emitting layer 251 on the first hole transport layer 241, wherein the light-emitting layer includes a light-emitting layer host material and a light-emitting layer guest material;

[0082] (5) vacuum evaporating an electron transport material on the first light-emitting layer 251 to form a first electron transport layer 261;

[0083] (6) vacuum evaporating a charge generating material on the first electron transport layer 261 to form the charge generating layer 27;

[0084] (7) vacuum evaporating a hole injection material on the charge generation layer 27 to form the second hole injection layer 232;

[0085] (8) vacuum evaporating a hole transport layer material on the second hole injection layer 232 to form a second hole transport layer 242;

[0086] (9) vacuum evaporating a second light-emitting layer 252 on the second hole transport layer 242, wherein the light-emitting layer includes a light-emitting layer host material and a light-emitting layer guest material;

[0087] (10) vacuum evaporating an electron transport material on the second light-emitting layer 252 to form a second electron transport layer 262;

[0088] (11) vacuum evaporating an electron injection material on the second electron transport layer 262 to form the electron injection layer 28;

[0089] (12) A cathode material is vacuum-evaporated on the electron injection layer 28 to form the cathode 29 .

[0090] The above description only describes the structure of a typical organic electroluminescent device and its preparation method. It should be understood that the present invention is not limited to this structure. The charge generation layer material or electron transport layer material of the present invention can be used in organic electroluminescent devices of any structure and can be prepared using any preparation method known in the art.

[0091] The present invention provides a display device comprising the organic electroluminescent device of the present invention, including but not limited to a display, a television, a tablet computer, a mobile communication terminal, and the like.

[0092] The synthesis method of the compound of the present invention is not particularly limited and can be synthesized by any method known to those skilled in the art. The following examples illustrate the synthesis process of the compound of the present invention.

[0093] Synthesis example 1

[0094] Synthesis of compound A1:

[0095]

[0096] 100 mmol of 2-bromo-5-chloropyridine, 100 mmol of p-chlorophenylboronic acid, 41.4 g of potassium carbonate (300 mmol), 800 mL of toluene, 200 mL of water, and 1 mol% of tetrakis(triphenylphosphine)palladium (Pd(PPh3)4) were added to a reaction flask and reacted at 80°C for 12 hours. After completion of the reaction, the reaction was stopped and the reactants were cooled to room temperature, water was added, filtered, and washed with water. The resulting solid was recrystallized and purified from toluene to obtain a white powder M1. The amount of Pd(PPh3)4 added was 1 mol% of the 2-bromo-5-chloropyridine.

[0097] 100 mmol of M1, 100 mmol of 2-nitrobenzeneboric acid, 41.4 g of potassium carbonate (300 mmol), 800 mL of toluene, 200 mL of water, and 1 mol% of tetrakis(triphenylphosphine)palladium (Pd(PPh3)4) were added to a reaction flask and reacted at 80°C for 12 hours. After the reaction was completed, the reaction was stopped and the reactants were cooled to room temperature, water was added, filtered, and washed with water. The resulting solid was recrystallized and purified from toluene to obtain a white powder M2. The amount of Pd(PPh3)4 added was 1 mol% of M1.

[0098] Add 100 mmol of M2, 41.4 g of potassium carbonate (300 mmol), and 800 mL of N,N-dimethylformamide (DMF) to a reaction flask and react at 120°C for 12 hours. After completion, the reaction was stopped and the reaction mixture was cooled to room temperature, added with water, filtered, and washed with water. The resulting solid was recrystallized from toluene to obtain a white powder, M3.

[0099] 100 mmol of M3, 100 mmol of bromobenzene, 41.4 g of potassium carbonate (300 mmol), 800 mL of xylene were added to a reaction flask, and 1 mol% of tetrakis(triphenylphosphine)palladium (Pd(PPh3)4) was added, and the reaction was carried out at 120°C for 12 hours. After the reaction was completed, the reaction was stopped, and the reactants were cooled to room temperature, added with water, filtered, and washed with water. The resulting solid was recrystallized and purified with toluene to obtain a white powder M4. The amount of Pd(PPh3)4 added was 1 mol% of M3.

[0100] To a reaction flask, 100 mmol of M4, 100 mmol of pinacol diboronate, 41.4 g of potassium carbonate (300 mmol), and 800 mL of dioxane were added, along with 1 mol% of Pd(PPh3)4. The mixture was reacted at 100°C for 12 h. After completion, the reaction was stopped and the product was cooled to room temperature, water was added, filtered, and washed. The resulting solid was recrystallized from toluene to obtain a white powder, M5. The amount of Pd(PPh3)4 added was 1 mol% of M4.

[0101] To a reaction flask, 100 mmol of 2,9-dichloro-1,10-phenanthroline, 100 mmol of phenylboronic acid, 41.4 g of potassium carbonate (300 mmol), 800 mL of THF, and 200 mL of water were added. 1 mol% of Pd(PPh3)4 was also added, and the mixture was reacted at 60°C for 12 hours. After completion, the reaction was stopped, and the reactants were cooled to room temperature, added with water, filtered, and washed with water. The resulting solid was recrystallized and purified from toluene to obtain a white powder M6. The amount of Pd(PPh3)4 added was 1 mol% of the 2,9-dichloro-1,10-phenanthroline.

[0102] To a reaction flask were added 100 mmol of M5, 100 mmol of M6, 41.4 g of potassium carbonate (300 mmol), 800 mL of tetrahydrofuran (THF), and 200 mL of water. 1 mol% of tetrakis(triphenylphosphine)palladium (Pd(PPh3)4) was also added, and the mixture was reacted at 60°C for 12 h. After completion of the reaction, the reaction was stopped, and the reactants were cooled to room temperature, added with water, filtered, and washed with water. The resulting solid was recrystallized and purified from toluene to obtain a white powder, A1. The amount of Pd(PPh3)4 added was 1 mol% of M5.

[0103] 1 H NMR (400MHz, Chloroform) δ8.79(d,J=8.0Hz,1H),8.75(d,J=8.0Hz,4H),8.55((d,J=7.2Hz,1H),8.41(d,J=7.6Hz,2H),8.32(d ,J=7.2Hz,2H),7.85(d,J=6.8Hz,1H),7.80(d,J=8.0Hz,1H),7.66-7.45(m,10H),7.34(d,J=8.0Hz,2H),7.10(t,J=7.2Hz,2H).

[0104] Synthesis example 2

[0105] Synthesis of compound A6:

[0106]

[0107] 100 mmol of 2-bromo-5-chloropyridine, 100 mmol of phenylboric acid, 41.4 g of potassium carbonate (300 mmol), 800 mL of toluene were added to a reaction flask, and 1 mol% of tetrakis(triphenylphosphine)palladium (Pd(PPh3)4) was added, and the reaction was carried out at 80°C for 12 hours. After the reaction was completed, the reaction was stopped, and the reactants were cooled to room temperature, added with water, filtered, and washed with water. The resulting solid was recrystallized and purified from toluene to obtain a white powder M1. The amount of Pd(PPh3)4 added was 1 mol% of the 2-bromo-5-chloropyridine.

[0108] To a reaction flask, 100 mmol of M1, 100 mmol of pinacol diboronate, 41.4 g of potassium carbonate (300 mmol), 800 mL of dioxane, and 1 mol% of Pd(PPh3)4 were added, and the mixture was reacted at 100°C for 12 hours. After completion, the reaction was stopped, and the reactants were cooled to room temperature, added with water, filtered, and washed with water. The resulting solid was recrystallized and purified from toluene to obtain a white powder, M2. The amount of Pd(PPh3)4 added was 1 mol% of M1.

[0109] 100 mmol of p-chlorobromobenzene, 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. 1 mol% of tetrakis(triphenylphosphine)palladium (Pd(PPh3)4) was also added, and the mixture was reacted 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, filtered, and washed with water. The resulting solid was recrystallized and purified from toluene to obtain a white powder M3. The amount of Pd(PPh3)4 added was 1 mol% of p-chlorobromobenzene.

[0110] To a reaction flask, 100 mmol of M3, 100 mmol of pinacol diboronate, 41.4 g of potassium carbonate (300 mmol), 800 mL of dioxane, and 1 mol% of Pd(PPh3)4 were added, and the mixture was reacted at 100°C for 12 hours. After completion, the reaction was stopped, and the reactants were cooled to room temperature, added with water, filtered, and washed with water. The resulting solid was recrystallized and purified from toluene to obtain a white powder, M4. The amount of Pd(PPh3)4 added was 1 mol% of M3.

[0111] To a reaction flask, 100 mmol of 2,9-dichloro-1,10-phenanthroline, 100 mmol of M4, 41.4 g of potassium carbonate (300 mmol), 800 mL of tetrahydrofuran (THF), and 200 mL of water were added. 1 mol% of Pd(PPh3)4 was also added, and the mixture was reacted at 60°C for 12 hours. After completion of the reaction, the reaction was stopped, and the reactants were cooled to room temperature, added with water, filtered, and washed with water. The resulting solid was recrystallized and purified from toluene to obtain a white powder, M5. The amount of Pd(PPh3)4 added was 1 mol% of the 2,9-dichloro-1,10-phenanthroline.

[0112] 100 mmol of 4-bromo-2-chloropyridine, 100 mmol of 2-nitrobenzeneboric acid, 41.4 g of potassium carbonate (300 mmol), 800 mL of toluene, 200 mL of water, and 1 mol% of tetrakis(triphenylphosphine)palladium (Pd(PPh3)4) were added to a reaction flask and reacted at 80°C for 12 hours. After completion of the reaction, the reaction was stopped and the reactants were cooled to room temperature, water was added, filtered, and washed with water. The resulting solid was recrystallized and purified from toluene to obtain a white powder M6. The amount of Pd(PPh3)4 added was 1 mol% of the 4-bromo-2-chloropyridine.

[0113] Add 100 mmol of M6, 41.4 g of potassium carbonate (300 mmol), and 800 mL of DMF to a reaction flask and react at 120°C for 12 h. After completion, the reaction was stopped and the product was cooled to room temperature, added with water, filtered, and washed with water. The resulting solid was recrystallized from toluene to obtain M7, a white powder.

[0114] To a reaction flask, 100 mmol of M7, 100 mmol of bromobenzene, 41.4 g of potassium carbonate (300 mmol), and 800 mL of xylene were added, along with 1 mol% of tetrakis(triphenylphosphine)palladium (Pd(PPh3)4), and the mixture was reacted at 120°C for 12 hours. After completion of the reaction, the reaction was stopped, and the reactants were cooled to room temperature, water was added, filtered, and washed with water. The resulting solid was recrystallized and purified from toluene to obtain a white powder, M8. The amount of Pd(PPh3)4 added was 1 mol% of M7.

[0115] 100 mmol of M8, 100 mmol of 4-chlorophenylboronic acid, 41.4 g of potassium carbonate (300 mmol), 800 mL of toluene, 200 mL of water, and 1 mol% of tetrakis(triphenylphosphine)palladium (Pd(PPh3)4) were added to a reaction flask and reacted at 80°C for 12 hours. After the reaction was completed, the reaction was stopped and the reactants were cooled to room temperature, water was added, filtered, and washed with water. The resulting solid was recrystallized and purified from toluene to obtain a white powder M9. The amount of Pd(PPh3)4 added was 1 mol% of M8.

[0116] To a reaction flask, 100 mmol of M9, 100 mmol of pinacol diboronate, 41.4 g of potassium carbonate (300 mmol), and 800 mL of dioxane were added, along with 1 mol% of Pd(PPh3)4. The mixture was reacted at 100°C for 12 h. After completion, the reaction was stopped and the product was cooled to room temperature, water was added, filtered, and washed. The resulting solid was recrystallized from toluene to obtain a white powder, M10. The amount of Pd(PPh3)4 added was 1 mol% of M9.

[0117] To a reaction flask were added 100 mmol of M5, 100 mmol of M10, 41.4 g of potassium carbonate (300 mmol), 800 mL of tetrahydrofuran (THF), and 200 mL of water. 1 mol% of tetrakis(triphenylphosphine)palladium (Pd(PPh3)4) was also added, and the mixture was reacted at 60°C for 12 h. After completion of the reaction, the reaction was stopped, and the reactants were cooled to room temperature, added with water, filtered, and washed with water. The resulting solid was recrystallized and purified from toluene to obtain a white powder, A6. The amount of Pd(PPh3)4 added was 1 mol% of M5.

[0118] 1H NMR (400MHz, Chloroform) δ8.94(s,1H),8.69(d,J=8.0Hz,6H),8.55(d,J=7.2Hz,1H),8.49(d,J=7.6Hz,1H),8.41(d,J=7.6Hz,2H),8.33(d,J=7.6Hz,2H),8 .01(d,J=8.0Hz,1H),7.93(d,J=7.6Hz,1H),7.87(d,J=7.2Hz,1H),7.68-7.45 (m,11H),7.34(d,J=7.6Hz,2H),7.25(d,J=7.6Hz,2H),7.14(t,J=7.2Hz,2H).

[0119] Synthesis example 3

[0120] Synthesis of compound A10:

[0121]

[0122] 100 mmol of p-chlorobromobenzene, 100 mmol of diphenylphosphine oxide, 41.4 g of potassium carbonate (300 mmol), 800 mL of toluene were added to a reaction flask, and 1 mol% of tetrakis(triphenylphosphine)palladium (Pd(PPh3)4) was added, and the reaction was carried out at 80°C for 12 hours. After the reaction was completed, the reaction was stopped, and the reactants were cooled to room temperature, added with water, filtered, and washed with water. The resulting solid was recrystallized and purified from toluene to obtain a white powder M1. The amount of Pd(PPh3)4 added was 1 mol% of p-chlorobromobenzene.

[0123] To a reaction flask, 100 mmol of M1, 100 mmol of pinacol diboronate, 41.4 g of potassium carbonate (300 mmol), 800 mL of dioxane, and 1 mol% of Pd(PPh3)4 were added, and the mixture was reacted at 100°C for 12 hours. After completion, the reaction was stopped, and the reactants were cooled to room temperature, added with water, filtered, and washed with water. The resulting solid was recrystallized and purified from toluene to obtain a white powder, M2. The amount of Pd(PPh3)4 added was 1 mol% of M1.

[0124] 100 mmol of 2,9-dichloro-1,10-phenanthroline, 100 mmol of M2, 41.4 g of potassium carbonate (300 mmol), 800 mL of THF, and 200 mL of water were added to a reaction flask. 1 mol% of Pd(PPh3)4 was also added, and the mixture was reacted at 60°C for 12 hours. After completion of the reaction, the reaction was stopped, and the reactants were cooled to room temperature, added with water, filtered, and washed with water. The resulting solid was recrystallized and purified from toluene to obtain a white powder, M3. The amount of Pd(PPh3)4 added was 1 mol% of the 2,9-dichloro-1,10-phenanthroline.

[0125] 100 mmol of 5-bromo-2-chloropyridine, 100 mmol of 2-nitrobenzeneboric acid, 41.4 g of potassium carbonate (300 mmol), 800 mL of toluene, 200 ml of water, and 1 mol% of tetrakis(triphenylphosphine)palladium (Pd(PPh3)4) were added to a reaction flask and reacted at 80°C for 12 hours. After completion of the reaction, the reaction was stopped and the reactants were cooled to room temperature, water was added, filtered, and washed with water. The resulting solid was recrystallized and purified from toluene to obtain a white powder M4. The amount of Pd(PPh3)4 added was 1 mol% of the 5-bromo-2-chloropyridine.

[0126] To a reaction flask, add 100 mmol of M4, 41.4 g of potassium carbonate (300 mmol), and 800 mL of DMF. The mixture was reacted at 120°C for 12 h. After completion, the reaction was stopped and the product was cooled to room temperature, added with water, filtered, and washed with water. The resulting solid was purified by recrystallization from toluene to obtain M5, a white powder.

[0127] To a reaction flask, 100 mmol of M5, 100 mmol of bromobenzene, 41.4 g of potassium carbonate (300 mmol), and 800 mL of xylene were added, along with 1 mol% of tetrakis(triphenylphosphine)palladium (Pd(PPh3)4), and the mixture was reacted at 120°C for 12 hours. After completion of the reaction, the reaction was stopped, and the reactants were cooled to room temperature, added with water, filtered, and washed with water. The resulting solid was recrystallized and purified from toluene to obtain a white powder, M6. The amount of Pd(PPh3)4 added was 1 mol% of M5.

[0128] 100 mmol of M6, 100 mmol of 4-chlorophenylboronic acid, 41.4 g of potassium carbonate (300 mmol), 800 mL of toluene, 200 mL of water, and 1 mol% of tetrakis(triphenylphosphine)palladium (Pd(PPh3)4) were added to a reaction flask and reacted at 80°C for 12 hours. After the reaction was completed, the reaction was stopped and the reactants were cooled to room temperature, water was added, filtered, and washed with water. The resulting solid was recrystallized and purified from toluene to obtain a white powder M7. The amount of Pd(PPh3)4 added was 1 mol% of M6.

[0129] To a reaction flask, 100 mmol of M7, 100 mmol of pinacol diboronate, 41.4 g of potassium carbonate (300 mmol), and 800 mL of dioxane were added, along with 1 mol% of Pd(PPh3)4. The mixture was reacted at 100°C for 12 h. After completion, the reaction was stopped and the product was cooled to room temperature, water was added, filtered, and washed. The resulting solid was recrystallized from toluene to obtain M8, a white powder. The amount of Pd(PPh3)4 added was 1 mol% of M7.

[0130] To a reaction flask were added 100 mmol of M3, 100 mmol of M8, 41.4 g of potassium carbonate (300 mmol), 800 mL of tetrahydrofuran (THF), and 200 mL of water. 1 mol% of tetrakis(triphenylphosphine)palladium (Pd(PPh3)4) was also added, and the mixture was reacted at 60°C for 12 h. After completion of the reaction, the reaction was stopped, and the reactants were cooled to room temperature, water was added, filtered, and washed with water. The resulting solid was purified by recrystallization from toluene to obtain a white powder A10. The amount of Pd(PPh3)4 added was 1 mol% of M3.

[0131] 1 H NMR (400MHz, Chloroform) δ9.31(s,1H),8.69(d,J=8.0Hz,4H),8.58(d,J=6.8Hz,1H),8.41(d,J=7.6Hz,2H),8.36(d,J=7.2Hz,2H),8.11(s ,1H),7.97(d,J=8.0Hz,2H),7.88(d,J=7.2Hz,1H),7.75(d,J=8.0Hz,4H),7.65-7.46(m,13H),7.35(d,J=8.0Hz,2H),7.12(t,J=7.6Hz,2H).

[0132] Other compounds of the present invention can be synthesized by selecting appropriate raw materials according to the ideas of the above synthesis examples, or by selecting any other appropriate methods and raw materials.

[0133] Example 1

[0134] A glass substrate coated with a 150nm thick ITO transparent conductive layer was ultrasonically treated in a commercial detergent, rinsed in deionized water, ultrasonically degreased in an acetone-ethanol mixed solvent, baked in a clean environment to completely remove moisture, cleaned with ultraviolet light and ozone, and bombarded with a low-energy cation beam to obtain a glass substrate with an anode.

[0135] Then, the glass substrate with the anode is placed in a vacuum chamber and evacuated to less than 10 -5 A first hole injection layer is vacuum-deposited on the anode layer film of the glass substrate with an anode. The materials of the first hole injection layer include hole injection layer material HT-11 and p-type dopant p-1. The deposition is performed by a multi-source co-evaporation method. The deposition rate of the hole injection layer material HT-11 is adjusted to 0.1 nm / s, and the deposition rate of the p-type dopant p-1 is adjusted to 3% of the deposition rate of the hole injection layer material HT-11. The total deposition thickness is 10 nm. The hole injection layer material HT-11 and the p-type dopant p-1 are as follows:

[0136]

[0137] Then, a hole transport layer material HT-3 was vacuum evaporated on the first hole injection layer to form a first hole transport layer. The evaporation rate was 0.1 nm / s and the evaporation film thickness was 80 nm. The structure of the hole transport layer material HT-3 was as follows:

[0138]

[0139] Then, a first light-emitting layer was vacuum-deposited on the first hole transport layer. The first light-emitting layer included a light-emitting layer host material BH-2 and a light-emitting layer guest material BD-1. The deposition was performed using a multi-source co-evaporation method. The deposition rate of the light-emitting layer host material BH-2 was adjusted to 0.1 nm / s, and the deposition rate of the light-emitting layer guest material BD-1 was adjusted to 3% of the deposition rate of the light-emitting layer host material BH-2. The deposition thickness was 30 nm. The compositions of the light-emitting layer host material BH-2 and the light-emitting layer guest material BD-1 were as follows:

[0140]

[0141] Then, a first electron transport layer was vacuum-deposited on the first light-emitting layer. The materials of the first electron transport layer were compound ET-30 and LiQ. The deposition rate of compound ET-30 was 0.1 nm / s, the deposition rate ratio of compound ET-30 to LiQ was 7:3, and the total deposition film thickness was 30 nm. The compounds ET-30 and LiQ were as follows:

[0142]

[0143] The first hole injection layer, the first hole transport layer, the first light-emitting layer and the first electron transport layer together constitute a first light-emitting unit;

[0144] Compound A1 provided by the present invention and metal ytterbium (Yb) were evaporated on the topmost first electron transport layer of the first light-emitting unit to form a charge generation layer. The evaporation rate of compound A1 was 0.01 nm / s, the evaporation rate ratio of compound A1 to Yb was 98:2, and the total film thickness was 10 nm.

[0145] A second hole injection layer is evaporated on the charge generation layer. The materials of the second hole injection layer include hole injection layer material HT-11 and p-type dopant p-1. The evaporation rate of the hole injection layer material HT-11 is adjusted to 0.1 nm / s, the evaporation rate ratio of the hole injection layer material HT-11 to the p-type dopant p-1 is 97:3, and the total evaporated film thickness is 10 nm.

[0146] Then, a hole transport layer material HT-3 was vacuum evaporated on the second hole injection layer to form a second hole transport layer, wherein the evaporation rate was 0.1 nm / s and the evaporation film thickness was 80 nm;

[0147] Then, a second light-emitting layer was vacuum-deposited on the second hole transport layer. The second light-emitting layer included a light-emitting layer host material BH-2 and a light-emitting layer guest material BD-1. The deposition was performed using a multi-source co-evaporation method. The deposition rate of the light-emitting layer host material BH-2 was adjusted to 0.1 nm / s, and the deposition rate of the light-emitting layer guest material BD-1 was adjusted to 3% of the deposition rate of the light-emitting layer host material BH-2. The total deposition thickness was 30 nm.

[0148] Then, a second electron transport layer was vacuum evaporated on the second light-emitting layer. The electron transport materials were compound ET-30 and LiQ. The evaporation rate of compound ET-30 was 0.1 nm / s, the evaporation rate ratio of compound ET-30 and LiQ was 7:3, and the total film thickness of the evaporation was 30 nm.

[0149] The second hole injection layer, the second hole transport layer, the second light-emitting layer and the second electron transport layer together constitute a second light-emitting unit;

[0150] Then, LiF with a thickness of 0.5 nm was vacuum-evaporated on the second electron transport layer at the top of the second light-emitting unit as an electron injection layer, wherein the evaporation rate was 0.1 nm / s;

[0151] Finally, an Al layer with a thickness of 150 nm was vacuum evaporated on the electron injection layer as a cathode electrode of the organic electroluminescent device, wherein the evaporation rate was 0.1 nm / s.

[0152] Example 2-3

[0153] The process is the same as that of Example 1 except that A6 and A10 are used as materials for the charge generation layer instead of A1.

[0154] Comparative Example 1

[0155] Except that the charge generation layer material is CGL00R1 instead of A1, the rest is the same as Example 1;

[0156]

[0157] Comparative Example 2

[0158] Except that CGL00R5 is used as the material of the charge generation layer instead of A1, the rest is the same as in Example 1;

[0159]

[0160] The organic electroluminescent device prepared by the above process was subjected to the following performance tests:

[0161] At the same brightness, a digital source meter and a luminance meter were used to measure the driving voltage, current efficiency, and device life of the organic electroluminescent devices prepared in Examples 1 to 3 and Comparative Examples 1 to 2. Specifically, the voltage was increased at a rate of 0.1 V per second, and the driving voltage, current efficiency, and device life of the organic electroluminescent devices were measured when the brightness of the organic electroluminescent devices reached 1000 cd / m 2 The voltage at this time is the driving voltage, and the current density at this time is measured at the same time; the ratio of brightness to current density is the current efficiency; the life test of LT95 is as follows: use a luminance meter at 1000cd / m 2 Under the same brightness, the current is kept constant and the brightness of the organic electroluminescent device is measured to be reduced to 950cd / m 2 The time is in hours. The results are shown in Table 1.

[0162] Table 1. Performance results of organic electroluminescent devices in Examples 1 to 3 and Comparative Examples 1 to 2

[0163]

[0164] As can be seen from Table 1, the organic electroluminescent devices prepared in Examples 1 to 3 employ Compounds A1, A6, and A10 provided herein as charge generation layer materials. Compared to Comparative Examples 1 and 2 employing materials known in the prior art as charge generation layer materials for the organic electroluminescent devices, the organic electroluminescent devices of the present invention exhibit lower driving voltages, higher current efficiency, and longer LT95 lifetimes. This demonstrates that the present invention, when employing the compound of formula (I) as a charge generation material in an organic electroluminescent device, can effectively reduce driving voltages, improve current efficiency, and extend device service life. The materials of the present invention exhibit significant performance improvements, particularly in terms of increasing the efficiency and extending the life of organic electroluminescent devices, enabling the production of high-performance organic electroluminescent devices.

[0165] The above description is only a preferred embodiment of the present invention and is not intended to limit the scope of protection of the present invention. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of the present invention are included in the scope of protection of the present invention.

Claims

1. A heterocyclic substituted phenanthroline compound, characterized in that: Having the structure shown in formula (I): in, Ar1 and Ar2 are each independently selected from C6-C 30 Aryl, unsubstituted or Rc-substituted C3-C 30 heteroaryl; L1 and L2 are each independently selected from a chemical bond, a C6-C 30 Arylene, unsubstituted or Rc-substituted C3-C 30 heteroarylene; X1-X4, Y1-Y4 are each independently selected from N or C, and at least one is N; The heteroatoms on the heteroaryl group and the heteroarylene group are each independently selected from O, S or N; The substituents Rc of each group are each independently selected from hydrogen, deuterium, halogen, nitro, cyano, C1-C4 alkyl, phenyl, biphenyl, terphenyl, pyridyl, pyrimidinyl or naphthyl.

2. The heterocyclic substituted phenanthroline compound according to claim 1, wherein Ar1 and Ar2 are each independently selected from C6-C 18 Aryl, unsubstituted or Rc-substituted C3-C 18 heteroaryl; and / or, L1 and L2 are each independently selected from a chemical bond, a C6-C 18 Arylene, unsubstituted or Rc-substituted C3-C 30 Heteroarylene.

3. The heterocyclic substituted phenanthroline compound according to claim 1, wherein Ar1 and Ar2 are each independently selected from the following groups which are unsubstituted or substituted by Ra: phenyl, biphenyl, terphenyl, naphthyl, phenanthrenyl, triphenylene, fluorenyl, benzofuranyl, dibenzofuranyl, benzothienyl, dibenzothienyl, 9,9-dimethylfluorenyl, 9,9-diphenylfluorenyl, spirofluorenyl, aromatic amino, and carbazolyl.

4. The heterocyclic substituted phenanthroline compound according to claim 1, wherein L1 and L2 are each independently selected from the following compounds which are chemically bonded, unsubstituted or substituted by Rc: phenyl, pyridyl, pyrimidinyl, quinoxalinyl, quinazoline, biphenyl, terphenyl, naphthyl, phenanthrenyl, triphenylene, fluorenyl, anthracenyl, dibenzofuranyl, dibenzothiophenyl, 9,9-dimethylfluorenyl, 9,9-diphenylfluorenyl, and spirofluorenyl.

5. The heterocyclic substituted phenanthroline compound according to claim 1, wherein A compound selected from A1-A25:

6. An organic electroluminescent device comprising a charge generation layer and an electron transport layer, characterized in that: The charge generation layer comprises at least one compound of formula (I) according to any one of claims 1 to 5.

7. The organic electroluminescent device according to claim 6, characterized in that: The charge generation layer includes metal Li or Yb, and the mass percentage of the metal Li or Yb is 0.5%-15% based on the mass of the charge generation layer.

8. The organic electroluminescent device according to claim 6, characterized in that: The charge generation layer has a thickness of 10 nm to 30 nm.

9. A display device, characterized in that: An organic electroluminescent device comprising the organic electroluminescent device according to any one of claims 6 to 8.

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