Organic electroluminescent compound and organic electroluminescent device containing same

Abstract

The present invention relates to an organic electroluminescent compound and an organic electroluminescent device comprising the same, the organic electroluminescent compound contains an oxazole organic compound of benzonaphthofuran, the HOMO and LUMO energy levels of the organic compound containing benzonaphthofuran have a high degree of matching with the adjacent energy levels, and the organic electroluminescent device has a high degree of matching with the adjacent energy levels. According to the organic compound containing the benzofuran, the carrier mobility of the organic compound containing the benzofuran is relatively balanced, so that the organic electroluminescent device containing the organic compound containing the benzofuran has relatively low driving voltage, relatively high luminous efficiency and relatively long service life; the organic light-emitting device can effectively reduce the driving voltage and prolong the service life.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of organic electroluminescence, in particular to an organic electroluminescence compound and an organic electroluminescence device comprising the same. BACKGROUND

[0002] An organic electroluminescence device (OLED) converts electric energy into light by applying electric power to an organic electroluminescence material, and generally comprises an anode, a cathode, and an organic layer formed between the two electrodes. The organic layer of the organic electroluminescence device can comprise a hole injection layer, a hole transport layer, a hole auxiliary layer, a light-emitting auxiliary layer, an electron blocking layer, a light-emitting layer (containing a host material and a dopant material), an electron buffer layer, a hole blocking layer, an electron transport layer, an electron injection layer, etc. The various materials used in the organic layer are classified as hole injection materials, hole transport materials, hole auxiliary materials, light-emitting auxiliary materials, electron blocking materials, light-emitting materials, electron buffer materials, hole blocking materials, electron transport materials, electron injection materials, etc. based on the functions achieved by each layer. In the organic electroluminescence device, holes from the anode and electrons from the cathode are injected into the light-emitting layer by applying a voltage, and excitons with high energy are generated by the recombination of holes and electrons. The organic light-emitting compound moves to the excited state by energy and emits light by the energy when the organic light-emitting compound returns from the excited state to the ground state.

[0003] The existing organic electroluminescence material has poor structural stability, and the HOMO and LUMO energy levels of the existing organic electroluminescence material have poor matching degree with adjacent energy levels, resulting in low stability and unbalanced carrier mobility of the organic electroluminescence material, which causes high driving voltage, low luminous efficiency, and short service life of the organic electroluminescence device containing the organic electroluminescence material, which seriously limits the application of the organic electroluminescence device. SUMMARY

[0004] The present application aims to overcome the problems of poor structural stability of the existing organic electroluminescence material, and poor matching degree of the HOMO and LUMO energy levels of the existing organic electroluminescence material with adjacent energy levels, which results in low stability and unbalanced carrier mobility of the organic electroluminescence material, causing high driving voltage, low luminous efficiency, and short service life of the organic electroluminescence device containing the organic electroluminescence material, which seriously limits the application of the organic electroluminescence device, and to provide an organic electroluminescence compound and its application.

[0005] The technical scheme adopted by the present application to solve at least one of the above technical problems is as follows: an organic electroluminescence compound, the structural formula of which is as follows:

[0006]

[0007] wherein L is selected from a bond, a substituted or unsubstituted C6-C60 aryl, and a substituted or unsubstituted C3-C60 heteroaryl; R 1 selected from halogen, cyano, a substituted or unsubstituted C6-C60 aryl, and a substituted or unsubstituted C3-C60 heteroaryl;

[0008] each of the substituents of the substituted C6-C60 aryl, the substituted C3-C60 heteroaryl is independently selected from one or a combination of at least two of deuterium, halogen, cyano, C1-C12 alkyl, C3-C12 cycloalkyl, C6-C30 aryl, C3-C30 heteroaryl, C6-C60 arylamine, C3-C60 heteroarylamine.

[0009] Preferably, the formula I is selected from one of the following 1-1 to 1-10 structures:

[0010]

[0011] Preferably, the R 1 selected from a substituted or unsubstituted phenyl, naphthyl, biphenyl, terphenyl, triphenylene, dimethylfluorenyl, diphenylfluorenyl, dibenzofuranyl, dibenzothiophenyl, benzonaphthofuranyl, benzonaphthothiophenyl;

[0012] each of the substituents of the substituted group is independently selected from one or a combination of at least two of deuterium, halogen, cyano, C1-C12 alkyl, C3-C12 cycloalkyl, C6-C30 aryl, C3-C30 heteroaryl, C6-C60 arylamine, C3-C60 heteroarylamine.

[0013] Preferably, the L is selected from a bond, a substituted or unsubstituted phenylene, a substituted or unsubstituted naphthylene, a substituted or unsubstituted biphenylene, a substituted or unsubstituted phenanthrylene, a substituted or unsubstituted anthrylene;

[0014] each of the substituents of the substituted group is independently selected from one or a combination of at least two of deuterium, halogen, cyano, C1-C12 alkyl, C3-C12 cycloalkyl, C6-C30 aryl, C3-C30 heteroaryl, C6-C60 arylamine, C3-C60 heteroarylamine.

[0015] Preferably, the formula I is selected from one of the following 1 to 365 structures:

[0016]

[0017]

[0018]

[0019]

[0020]

[0021]

[0022]

[0023]

[0024]

[0025]

[0026] An organic electroluminescent material comprising the aforementioned organic electroluminescent compound.

[0027] An organic electroluminescent device includes a cathode, an anode, and an organic layer located between the cathode and the anode, characterized in that: the organic layer includes the aforementioned organic electroluminescent compound or the aforementioned organic electroluminescent material.

[0028] Preferably, the organic layer includes an electron transport layer, which includes the aforementioned organic electroluminescent compound or the aforementioned organic electroluminescent material.

[0029] Preferably, the organic layer includes a light-emitting layer, and the material of the light-emitting layer comprises a host material and a guest material; the host material comprises the aforementioned organic electroluminescent material.

[0030] Preferably, the guest material comprises a phosphorescent dopant or a thermally activated delayed fluorescence compound, wherein the phosphorescent dopant comprises a transition metal complex.

[0031] An application of the above-mentioned organic electroluminescent device, wherein the organic electroluminescent device is used in optoelectronics, medicine, biotechnology, optical fiber, lighting equipment, electrophotographic photosensitive material, photoelectric converter, organic solar cell, switching element, organic light-emitting field-effect transistor, image sensor or dye laser.

[0032] Compared with the prior art, the advantages of the present invention are as follows:

[0033] The oxazole-based organic compounds containing benzonaphthylfuran provided by this invention, based on the structure of Formula I, further limit the types of substituents to improve the structural stability of the compounds, and the HOMO and LUMO energy levels of the organic compounds containing benzonaphthylfuran have a high degree of matching with adjacent energy levels, so that the carrier mobility of the organic compounds containing benzonaphthylfuran is more balanced, thereby enabling the organic electroluminescent devices containing the organic compounds containing benzonaphthylfuran to have a lower driving voltage, higher luminous efficiency and longer lifetime.

[0034] The organic compounds containing benzonaphthofuran provided by this invention have good electron transport properties and can be used as electron transport materials or luminescent materials.

[0035] The organic electroluminescent material of the present invention includes an oxazole-based organic compound containing benzonaphthene furan based on the structure of Formula I, thereby enabling the organic electroluminescent device containing the organic electroluminescent material to have a lower driving voltage, higher luminous efficiency and longer lifetime. Attached Figure Description

[0036] Figure 1 This is a schematic diagram of the structure of the organic electroluminescent device in an embodiment of the present invention;

[0037] In this design, 1 is the substrate, 2 is the anode, 3 is the hole injection layer, 4 is the hole transport layer, 5 is the light-emitting layer, 6 is the electron transport layer, 7 is the electron injection layer, and 8 is the cathode. Detailed Implementation

[0038] The present invention will be further described in detail below with reference to the accompanying drawings and embodiments.

[0039] As used in this invention, the term "organic electroluminescent material" refers to a material that can be used in an organic electroluminescent element and may include at least one compound. If desired, the organic electroluminescent material may be included in any layer constituting the organic electroluminescent element. For example, the organic electroluminescent material may be a hole injection material, a hole transport material, an electron blocking material, a light-emitting auxiliary material, a light-emitting layer material (including a host material and a dopant material), an electron buffer material, a hole blocking material, an electron transport material, an electron injection material, etc.

[0040] As used in this invention, the term "halogen" may include fluorine, chlorine, bromine, or iodine.

[0041] As used in this invention, the term "C1-C30 alkyl" refers to a monovalent substituent derived from a straight-chain or branched saturated hydrocarbon having 1 to 30 carbon atoms, and "C1-C30 alkyl" includes, but is not limited to, methyl, ethyl, propyl, isobutyl, sec-butyl, tert-butyl, pentyl, isopentyl, and hexyl.

[0042] As used in this invention, the term "C3-C30 cycloalkyl" refers to a monovalent substituent derived from a monocyclic or polycyclic hydrocarbon having 1 to 30 carbon atoms in its main ring chain, and "C3-C30 cycloalkyl" includes, but is not limited to, cyclopropyl, cyclobutyl, and adamantyl.

[0043] In this invention, aryl and arylene groups include monocyclic, polycyclic, or fused-ring aryl groups, and the rings may be interrupted by short non-aromatic units and may include spiro structures; aryl groups include, but are not limited to, phenyl, biphenyl, terphenyl, naphthyl, phenanthryl, anthracene, fluorenyl, and spirodifluorenyl.

[0044] In this invention, heteroaryl and hypoaryl groups include monocyclic, polycyclic, or fused-ring heteroaryl groups, wherein the rings can be interrupted by short non-aromatic units, and the heteroatoms include nitrogen, oxygen, and sulfur; heteroaryl groups include, but are not limited to, furanyl, phenylthio, pyrroleyl, imidazolyl, pyrazolyl, thiazolyl, thiadiazolyl, isothiazolyl, isoxazolyl, oxazolyl, oxadiazolyl, triazinyl, tetraazinyl, triazolyl, tetraazolyl, furazolidyl, pyridyl, pyrazinyl, pyrimidinyl, and pyridyl. Azinyl, benzofuranyl, benzothiophenyl, isobenzofuranyl, dibenzofuranyl, dibenzothiophenyl, benzimidazolyl, benzothiazolyl, benzoisothiazolyl, benzoisooxazolyl, benzooxazolyl, isoindolyl, indolyl, inzolyl, benzothiadiazolyl, quinolinyl, isoquinolinyl, cenolinyl, quinazolinyl, quinoxalolinyl, carbazoleyl, phenoxazinyl, phenthiazinyl, phenanthidyl, benzo-m-dioxacyclopentenyl, dihydroacridyl, and their derivatives.

[0045] As used in this invention, the term "substituted" means that a hydrogen atom in a compound is replaced by another substituent. This position is not limited to a specific position, as long as the hydrogen at that position can be replaced by a substituent. When two or more substituents are present, the two or more substituents can be the same or different.

[0046] As used in this invention, unless otherwise stated, a hydrogen atom includes protium, deuterium, and tritium.

[0047] In this invention, the definition of a group specifies a range of carbon atoms, and the number of carbon atoms is any integer within the defined range, such as C6-C60 aryl. The number of carbon atoms representing an aryl group can be any integer within the range of 6-60, such as 6, 8, 10, 15, 20, 30, 35, 40, 45, 50, 55 or 60, etc.

[0048] In this invention, the general formula for synthesizing the compound represented by Formula I is as follows:

[0049] 1. When L is a substituted or unsubstituted C6-C60 aryl group, or a substituted or unsubstituted C3-C60 heteroaryl group:

[0050]

[0051] 2. When L is the connection key:

[0052]

[0053] Example 1

[0054] This embodiment provides a method for preparing compound 2, comprising the following steps:

[0055]

[0056] Synthesis of intermediate 2-1: A 100 mL three-necked round-bottom flask was placed with a stir bar and a reflux tube attached. Under nitrogen protection, the starting materials benzoxazole (1 mmol), m-chlorobromobenzene (1.2 mmol), palladium acetate (0.05 mmol), cesium carbonate (2 mmol), and DMSO (10 mL) were added sequentially. The mixture was cooled to 0°C, and then n-butyllithium (0.05 mmol) was slowly added dropwise. After the addition was complete, the temperature was slowly raised to 50°C and reacted for 14 hours. After the reaction was completed, the mixture was cooled to room temperature, quenched with saturated ammonium chloride aqueous solution, extracted with ethyl acetate, washed with saturated sodium chloride, and the organic phase was dried over anhydrous magnesium sulfate. The solvent was removed using a rotary evaporator, and the crude product was separated by column chromatography (ethyl acetate: n-hexane = 1:50) to obtain intermediate 2-1 (yield 73%).

[0057] Synthesis of intermediate 2-2: A 100 mL three-necked round-bottom flask was placed with a stir bar and a reflux tube attached. Under nitrogen protection, intermediate 2-1 (1 mmol), diboronate (1.1 mmol), 1,4-dioxane (10 mL), Pd(dppf)Cl2 (0.03 mmol), and potassium acetate (2.5 mmol) were added sequentially. The mixture was heated to 100 °C and reacted for 5 hours. After the reaction was completed, the mixture was cooled to room temperature and extracted with ethyl acetate. The organic phase was dried over anhydrous magnesium sulfate, and the solvent was removed using a rotary evaporator. The crude product was separated by column chromatography (ethyl acetate: n-hexane = 1:50) to obtain intermediate 2-2 (yield 81%).

[0058] Synthesis of intermediate 2-A: Take a 100 mL three-necked round-bottom flask and place a stir bar and a reflux tube on top. Under nitrogen protection, add intermediate 2-2 (1 mmol), 2,4-dichloro-6-phenyl-[1,3,5]triazine (0.9 mmol), Pd(dppf)Cl2 (0.03 mmol), potassium carbonate (2.5 mmol), and 1,4-dioxane / water (10 mL / 2 mL). Heat to 90 °C and react for 5 hours. After the reaction is complete, cool to room temperature, filter, wash the filter cake twice with deionized water, and wash twice with tetrahydrofuran to obtain intermediate 2-A (yield 86%).

[0059] Synthesis of Compound 2: A 100 mL three-necked round-bottom flask was placed with a stir bar and a reflux tube attached. Under nitrogen protection, intermediate 2-A (1 mmol), intermediate 2-B (1.1 mmol), Pd(dppf)Cl2 (0.03 mmol), potassium carbonate (2.5 mmol), and 1,4-dioxane / water (10 mL / 2 mL) were added sequentially. The mixture was heated to 90 °C and reacted for 5 hours. After the reaction was completed, the mixture was cooled to room temperature, filtered, and the filter cake was washed twice with deionized water and twice with ethanol. The crude product was then purified twice by recrystallization from o-dichlorobenzene to obtain Compound 2 (yield 49%).

[0060] Elemental analysis: C 38 H 22 Theoretical N4O2 values: C, 80.55; H, 3.91; N, 9.89; O, 5.65; Measured values: C, 80.58; H, 3.90; N, 9.87; HRMS(ESI) m / z [M+H]+: Theoretical value: 566.1743; Measured value: 567.0263.

[0061] Example 2

[0062] This embodiment provides a method for preparing compound 24. The basic steps are the same as in Example 1, and the specific preparation process is as follows:

[0063]

[0064] Synthesis of intermediate 24-1: A 100 mL three-necked round-bottom flask was placed with a stir bar and a reflux tube attached. Under nitrogen protection, the following starting materials were added sequentially: benzoxazole (1 mmol), 2-bromo-6-chloronaphthalene (1.2 mmol), palladium acetate (0.05 mmol), cesium carbonate (2 mmol), and DMSO (10 mL). The mixture was cooled to 0°C, and then n-butyllithium (0.05 mmol) was slowly added dropwise. After the addition was complete, the mixture was slowly heated to 50°C and reacted for 14 hours. After the reaction was completed, the mixture was cooled to room temperature, quenched with saturated ammonium chloride aqueous solution, extracted with ethyl acetate, washed with saturated sodium chloride, and the organic phase was dried over anhydrous magnesium sulfate. The solvent was removed using a rotary evaporator. The crude product was separated by column chromatography (ethyl acetate: n-hexane = 1:50) to obtain intermediate 24-1 (yield 83%).

[0065] Synthesis of intermediate 24-2: A 100 mL three-necked round-bottom flask was placed with a stir bar and a reflux tube attached. Under nitrogen protection, intermediate 24-1 (1 mmol), diboronate (1.1 mmol), 1,4-dioxane (10 mL), Pd(dppf)Cl2 (0.03 mmol), and potassium acetate (2.5 mmol) were added sequentially. The mixture was heated to 100 °C and reacted for 5 hours. After the reaction was completed, the mixture was cooled to room temperature and extracted with ethyl acetate. The organic phase was dried over anhydrous magnesium sulfate, and the solvent was removed using a rotary evaporator. The crude product was separated by column chromatography (ethyl acetate: n-hexane = 1:50) to obtain intermediate 24-2 (yield 79%).

[0066] Synthesis of intermediate 24-A: A 100 mL three-necked round-bottom flask was placed with a stir bar and a reflux tube attached. Under nitrogen protection, intermediate 24-2 (1 mmol), 2,4-dichloro-6-phenyl-[1,3,5]triazine (0.9 mmol), Pd(dppf)Cl2 (0.03 mmol), potassium carbonate (2.5 mmol), and 1,4-dioxane / water (10 mL / 2 mL) were added sequentially. The mixture was heated to 90 °C and reacted for 5 hours. After the reaction was completed, the mixture was cooled to room temperature, filtered, and the filter cake was washed twice with deionized water and twice with tetrahydrofuran to obtain intermediate 24-A (yield 86%).

[0067] Synthesis of compound 24: A 100 mL three-necked round-bottom flask was placed with a stir bar and a reflux tube attached. Under nitrogen protection, intermediate 24-A (1 mmol), intermediate 1-B (1.1 mmol), Pd(dppf)Cl2 (0.03 mmol), potassium carbonate (2.5 mmol), and 1,4-dioxane / water (10 mL / 2 mL) were added sequentially. The mixture was heated to 90 °C and reacted for 5 hours. After the reaction was completed, the mixture was cooled to room temperature, filtered, and the filter cake was washed twice with deionized water and twice with ethanol. The crude product was then purified twice by recrystallization from o-dichlorobenzene to obtain compound 24 (yield 49%).

[0068] Elemental analysis: C 42 H 24 Theoretical values ​​for N4O2: C, 81.80; H, 3.92; N, 9.09; O, 5.19; Measured values: C, 81.83; H, 3.91; N, 9.07; HRMS(ESI) m / z [M+H]+: Theoretical value: 616.1899; Measured value: 617.1389.

[0069] Example 3

[0070] This embodiment provides a method for preparing compound 75. The basic steps are the same as in Example 1, and the specific preparation process is as follows:

[0071]

[0072] Synthesis of intermediate 75-1: A 100 mL three-necked round-bottom flask was placed with a stir bar and a reflux tube attached. Under nitrogen protection, the following ingredients were added sequentially: benzoxazole (1 mmol), 3-bromo-5-chloro-1,1'-biphenyl (1.2 mmol), palladium acetate (0.05 mmol), cesium carbonate (2 mmol), and DMSO (10 mL). The mixture was cooled to 0°C, and then n-butyllithium (0.05 mmol) was slowly added dropwise. After the addition was complete, the mixture was slowly heated to 50°C and reacted for 14 hours. After the reaction was completed, the mixture was cooled to room temperature, quenched with saturated ammonium chloride aqueous solution, extracted with ethyl acetate, washed with saturated sodium chloride, and the organic phase was dried over anhydrous magnesium sulfate. The solvent was removed using a rotary evaporator. The crude product was separated by column chromatography (ethyl acetate: n-hexane = 1:50) to obtain intermediate 75-1 (yield 80%).

[0073] Synthesis of intermediate 75-2: A 100 mL three-necked round-bottom flask was placed with a stir bar and a reflux tube attached. Under nitrogen protection, intermediate 75-1 (1 mmol), diboronate (1.1 mmol), 1,4-dioxane (10 mL), Pd(dppf)Cl2 (0.03 mmol), and potassium acetate (2.5 mmol) were added sequentially. The mixture was heated to 100 °C and reacted for 5 hours. After the reaction was completed, the mixture was cooled to room temperature and extracted with ethyl acetate. The organic phase was dried over anhydrous magnesium sulfate, and the solvent was removed using a rotary evaporator. The crude product was separated by column chromatography (ethyl acetate: n-hexane = 1:50) to obtain intermediate 75-2 (yield 72%).

[0074] Synthesis of intermediate 75-A: A 100 mL three-necked round-bottom flask was placed with a stir bar and a reflux tube attached. Under nitrogen protection, intermediate 75-2 (1 mmol), 2,4-dichloro-6-phenyl-[1,3,5]triazine (0.9 mmol), Pd(dppf)Cl2 (0.03 mmol), potassium carbonate (2.5 mmol), and 1,4-dioxane / water (10 mL / 2 mL) were added sequentially. The mixture was heated to 90 °C and reacted for 5 hours. After the reaction was completed, the mixture was cooled to room temperature, filtered, and the filter cake was washed twice with deionized water and twice with tetrahydrofuran to obtain intermediate 75-A (yield 86%).

[0075] Synthesis of compound 75: A 100 mL three-necked round-bottom flask was placed with a stir bar and a reflux tube attached. Under nitrogen protection, intermediates 75-A (1 mmol), 3-B (1.1 mmol), Pd(dppf)Cl2 (0.03 mmol), potassium carbonate (2.5 mmol), and 1,4-dioxane / water (10 mL / 2 mL) were added sequentially. The mixture was heated to 90 °C and reacted for 5 hours. After the reaction was completed, the mixture was cooled to room temperature, filtered, and the filter cake was washed twice with deionized water and twice with ethanol. The crude product was then purified twice by recrystallization from o-dichlorobenzene to obtain compound 75 (yield 52%).

[0076] Elemental analysis: C 44 H 26 Theoretical values ​​for N4O2: C, 82.23; H, 4.08; N, 8.72; O, 4.98; Measured values: C, 82.26; H, 4.07; N, 8.70; HRMS(ESI) m / z [M+H]+: Theoretical value: 642.2056; Measured value: 643.1563.

[0077] Example 4

[0078] This embodiment provides a method for preparing compound 152. The basic steps are the same as in Example 1, and the specific preparation process is as follows:

[0079]

[0080] Synthesis of intermediate 152-1: A 100 mL three-necked round-bottom flask was placed with a stir bar and a reflux tube attached. Under nitrogen protection, the starting materials benzoxazole (1 mmol), m-chlorobromobenzene (1.2 mmol), palladium acetate (0.05 mmol), cesium carbonate (2 mmol), and DMSO (10 mL) were added sequentially. The mixture was cooled to 0°C, and then n-butyllithium (0.05 mmol) was slowly added dropwise. After the addition was complete, the temperature was slowly raised to 50°C and reacted for 14 hours. After the reaction was completed, the mixture was cooled to room temperature, quenched with saturated ammonium chloride aqueous solution, extracted with ethyl acetate, washed with saturated sodium chloride, and the organic phase was dried with anhydrous magnesium sulfate. The solvent was removed using a rotary evaporator. The crude product was separated by column chromatography (ethyl acetate: n-hexane = 1:50) to obtain intermediate 152-1 (yield 83%).

[0081] Synthesis of intermediate 152-2: A 100 mL three-necked round-bottom flask was placed with a stir bar and a reflux tube attached. Under nitrogen protection, intermediate 152-1 (1 mmol), diboronate (1.1 mmol), 1,4-dioxane (10 mL), Pd(dppf)Cl2 (0.03 mmol), and potassium acetate (2.5 mmol) were added sequentially. The mixture was heated to 100 °C and reacted for 5 hours. After the reaction was completed, the mixture was cooled to room temperature and extracted with ethyl acetate. The organic phase was dried over anhydrous magnesium sulfate and the solvent was removed using a rotary evaporator. The crude product was separated by column chromatography (ethyl acetate: n-hexane = 1:50) to obtain intermediate 152-2 (yield 72%).

[0082] Synthesis of intermediate 152-A: Take a 100 mL three-necked round-bottom flask and place a stir bar and a reflux tube on top. Under nitrogen protection, add intermediate 152-2 (1 mmol), 2,4-dichloro-6-naphth-1-yl-[1,3,5]triazine (0.9 mmol), Pd(dppf)Cl2 (0.03 mmol), potassium carbonate (2.5 mmol), and 1,4-dioxane / water (10 mL / 2 mL). Heat to 90 °C and react for 5 hours. After the reaction is complete, cool to room temperature, filter, wash the filter cake twice with deionized water, and wash twice with tetrahydrofuran to obtain intermediate 152-A (yield 86%).

[0083] Synthesis of compound 152: A 100 mL three-necked round-bottom flask was placed with a stir bar and a reflux tube attached. Under nitrogen protection, intermediate 152-A (1 mmol), intermediate 3-B (1.1 mmol), Pd(dppf)Cl2 (0.03 mmol), potassium carbonate (2.5 mmol), and 1,4-dioxane / water (10 mL / 2 mL) were added sequentially. The mixture was heated to 90 °C and reacted for 5 hours. After the reaction was completed, the mixture was cooled to room temperature, filtered, and the filter cake was washed twice with deionized water and twice with ethanol. The crude product was then purified twice by recrystallization from o-dichlorobenzene to obtain compound 152 (yield 57%).

[0084] Elemental analysis: C 42 H 24 Theoretical values ​​for N4O2: C, 81.80; H, 3.92; N, 9.09; O, 5.19; Measured values: C, 81.83; H, 3.91; N, 9.07; HRMS(ESI) m / z [M+H]+: Theoretical value: 616.1899; Measured value: 617.1389.

[0085] Example 5

[0086] This embodiment provides a method for preparing compound 204. The basic steps are the same as in Example 1, and the specific preparation process is as follows:

[0087]

[0088] Synthesis of intermediate 204-1: A 100 mL three-necked round-bottom flask was placed with a stir bar and a reflux tube attached. Under nitrogen protection, the following ingredients were added sequentially: benzoxazole (1 mmol), 2-bromo-5-chloro-1,1'-biphenyl (1.2 mmol), palladium acetate (0.05 mmol), cesium carbonate (2 mmol), and DMSO (10 mL). The mixture was cooled to 0°C, and then n-butyllithium (0.05 mmol) was slowly added dropwise. After the addition was complete, the mixture was slowly heated to 50°C and reacted for 14 hours. After the reaction was completed, the mixture was cooled to room temperature, quenched with saturated ammonium chloride aqueous solution, extracted with ethyl acetate, washed with saturated sodium chloride, and the organic phase was dried over anhydrous magnesium sulfate. The solvent was removed using a rotary evaporator. The crude product was separated by column chromatography (ethyl acetate: n-hexane = 1:50) to obtain intermediate 204-1 (yield 77%).

[0089] Synthesis of intermediate 204-2: A 100 mL three-necked round-bottom flask was placed with a stir bar and a reflux tube attached. Under nitrogen protection, intermediate 204-1 (1 mmol), diboronate (1.1 mmol), 1,4-dioxane (10 mL), Pd(dppf)Cl2 (0.03 mmol), and potassium acetate (2.5 mmol) were added sequentially. The mixture was heated to 100 °C and reacted for 5 hours. After the reaction was completed, the mixture was cooled to room temperature and extracted with ethyl acetate. The organic phase was dried over anhydrous magnesium sulfate, and the solvent was removed using a rotary evaporator. The crude product was separated by column chromatography (ethyl acetate: n-hexane = 1:50) to obtain intermediate 204-2 (yield 84%).

[0090] Synthesis of intermediate 204-A: Take a 100 mL three-necked round-bottom flask and place a stir bar and a reflux tube on top. Under nitrogen protection, add intermediate 204-2 (1 mmol), 2,4-dichloro-6-naphth-1-yl-[1,3,5]triazine (0.9 mmol), Pd(dppf)Cl2 (0.03 mmol), potassium carbonate (2.5 mmol), and 1,4-dioxane / water (10 mL / 2 mL). Heat to 90 °C and react for 5 hours. After the reaction is complete, cool to room temperature, filter, wash the filter cake twice with deionized water, and wash twice with tetrahydrofuran to obtain intermediate 204-A (yield 74%).

[0091] Synthesis of compound 204: A 100 mL three-necked round-bottom flask was placed with a stir bar and a reflux tube attached. Under nitrogen protection, intermediate 204-A (1 mmol), intermediate 4-B (1.1 mmol), Pd(dppf)Cl2 (0.03 mmol), potassium carbonate (2.5 mmol), and 1,4-dioxane / water (10 mL / 2 mL) were added sequentially. The mixture was heated to 90 °C and reacted for 5 hours. After the reaction was completed, the mixture was cooled to room temperature, filtered, and the filter cake was washed twice with deionized water and twice with ethanol. The crude product was then purified twice by recrystallization from o-dichlorobenzene to obtain compound 204 (60% yield).

[0092] Elemental analysis: C 48 H 28 Theoretical values ​​for N4O2: C, 83.22; H, 4.07; N, 8.09; O, 4.62; Measured values: C, 83.25; H, 4.06; N, 8.07; HRMS(ESI) m / z [M+H]+: Theoretical value: 692.2212; Measured value: 693.1755.

[0093] Example 6

[0094] This embodiment provides a method for preparing compound 230. The basic steps are the same as in Example 1, and the specific preparation process is as follows:

[0095]

[0096] Synthesis of intermediate 230-1: A 100 mL three-necked round-bottom flask was placed with a stir bar and a reflux tube attached. Under nitrogen protection, the following starting materials were added sequentially: benzoxazole (1 mmol), p-chlorobromobenzene (1.2 mmol), palladium acetate (0.05 mmol), cesium carbonate (2 mmol), and DMSO (10 mL). The mixture was cooled to 0°C, and then n-butyllithium (0.05 mmol) was slowly added dropwise. After the addition was complete, the temperature was slowly raised to 50°C and the reaction was carried out for 14 hours. After the reaction was completed, the mixture was cooled to room temperature, quenched with saturated ammonium chloride aqueous solution, extracted with ethyl acetate, washed with saturated sodium chloride, and the organic phase was dried with anhydrous magnesium sulfate. The solvent was removed using a rotary evaporator. The crude product was separated by column chromatography (ethyl acetate: n-hexane = 1:50) to obtain intermediate 230-1 (yield 82%).

[0097] Synthesis of intermediate 230-2: A 100 mL three-necked round-bottom flask was placed with a stir bar and a reflux tube attached. Under nitrogen protection, intermediate 230-1 (1 mmol), diboronate (1.1 mmol), 1,4-dioxane (10 mL), Pd(dppf)Cl2 (0.03 mmol), and potassium acetate (2.5 mmol) were added sequentially. The mixture was heated to 100 °C and reacted for 5 hours. After the reaction was completed, the mixture was cooled to room temperature and extracted with ethyl acetate. The organic phase was dried over anhydrous magnesium sulfate, and the solvent was removed using a rotary evaporator. The crude product was separated by column chromatography (ethyl acetate: n-hexane = 1:50) to obtain intermediate 230-2 (yield 75%).

[0098] Synthesis of intermediate 230-A: A 100 mL three-necked round-bottom flask was placed with a stir bar and a reflux tube attached. Under nitrogen protection, intermediate 230-2 (1 mmol), 2-(4-biphenyl)-4,6-dichloro-1,3,5-triazine (0.9 mmol), Pd(dppf)Cl2 (0.03 mmol), potassium carbonate (2.5 mmol), and 1,4-dioxane / water (10 mL / 2 mL) were added sequentially. The mixture was heated to 90 °C and reacted for 5 hours. After the reaction was completed, the mixture was cooled to room temperature, filtered, and the filter cake was washed twice with deionized water and twice with tetrahydrofuran to obtain intermediate 230-A (yield 63%).

[0099] Synthesis of compound 230: A 100 mL three-necked round-bottom flask was placed with a stir bar and a reflux tube attached. Under nitrogen protection, intermediate 230-A (1 mmol), intermediate 2-B (1.1 mmol), Pd(dppf)Cl2 (0.03 mmol), potassium carbonate (2.5 mmol), and 1,4-dioxane / water (10 mL / 2 mL) were added sequentially. The mixture was heated to 90 °C and reacted for 5 hours. After the reaction was completed, the mixture was cooled to room temperature, filtered, and the filter cake was washed twice with deionized water and twice with ethanol. The crude product was then purified twice by recrystallization from o-dichlorobenzene to obtain compound 230 (yield 55%).

[0100] Elemental analysis: C 44 H 26 Theoretical values ​​for N4O2: C, 82.23; H, 4.08; N, 8.72; O, 4.98; Measured values: C, 82.26; H, 4.07; N, 8.70; HRMS(ESI) m / z [M+H]+: Theoretical value: 642.2056; Measured value: 643.1563.

[0101] Example 7

[0102] This embodiment provides a method for preparing compound 306. The basic steps are the same as in Example 1, and the specific preparation process is as follows:

[0103]

[0104] Synthesis of intermediate 306-1: A 100 mL three-necked round-bottom flask was placed with a stir bar and a reflux tube attached. Under nitrogen protection, the starting materials benzoxazole (1 mmol), 2-bromo-6-chlorophenanthrene (1.2 mmol), palladium acetate (0.05 mmol), cesium carbonate (2 mmol), and DMSO (10 mL) were added sequentially. The mixture was cooled to 0°C, and then n-butyllithium (0.05 mmol) was slowly added dropwise. After the addition was complete, the temperature was slowly raised to 50°C and reacted for 14 hours. After the reaction was completed, the mixture was cooled to room temperature, quenched with saturated ammonium chloride aqueous solution, extracted with ethyl acetate, washed with saturated sodium chloride, and the organic phase was dried with anhydrous magnesium sulfate. The solvent was removed using a rotary evaporator. The crude product was separated by column chromatography (ethyl acetate: n-hexane = 1:50) to obtain intermediate 306-1 (yield 73%).

[0105] Synthesis of intermediate 306-2: A 100 mL three-necked round-bottom flask was placed with a stir bar and a reflux tube attached. Under nitrogen protection, intermediate 306-1 (1 mmol), diboronate (1.1 mmol), 1,4-dioxane (10 mL), Pd(dppf)Cl2 (0.03 mmol), and potassium acetate (2.5 mmol) were added sequentially. The mixture was heated to 100 °C and reacted for 5 hours. After the reaction was completed, the mixture was cooled to room temperature and extracted with ethyl acetate. The organic phase was dried over anhydrous magnesium sulfate, and the solvent was removed using a rotary evaporator. The crude product was separated by column chromatography (ethyl acetate: n-hexane = 1:50) to obtain intermediate 306-2 (yield 82%).

[0106] Synthesis of intermediate 306-A: A 100 mL three-necked round-bottom flask was placed with a stir bar and a reflux tube attached. Under nitrogen protection, intermediate 306-2 (1 mmol), 2,4-dichloro-6-phenyl-[1,3,5]triazine (0.9 mmol), Pd(dppf)Cl2 (0.03 mmol), potassium carbonate (2.5 mmol), and 1,4-dioxane / water (10 mL / 2 mL) were added sequentially. The mixture was heated to 90 °C and reacted for 5 hours. After the reaction was completed, the mixture was cooled to room temperature, filtered, and the filter cake was washed twice with deionized water and twice with tetrahydrofuran to obtain intermediate 306-A (yield 53%).

[0107] Synthesis of compound 306: A 100 mL three-necked round-bottom flask was placed with a stir bar and a reflux tube attached. Under nitrogen protection, intermediates 306-A (1 mmol), 1-B (1.1 mmol), Pd(dppf)Cl2 (0.03 mmol), potassium carbonate (2.5 mmol), and 1,4-dioxane / water (10 mL / 2 mL) were added sequentially. The mixture was heated to 90 °C and reacted for 5 hours. After the reaction was completed, the mixture was cooled to room temperature, filtered, and the filter cake was washed twice with deionized water and twice with ethanol. The crude product was then purified twice by recrystallization from o-dichlorobenzene to obtain compound 306 (yield 62%).

[0108] Elemental analysis: C 46 H 26 Theoretical values ​​for N4O2: C, 82.87; H, 3.93; N, 8.40; O, 4.80; Measured values: C, 82.90; H, 3.92; N, 8.38; HRMS(ESI) m / z [M+H]+: Theoretical value: 666.2056; Measured value: 667.1572.

[0109] Example 8

[0110] This embodiment provides a method for preparing compound 344. The basic steps are the same as in Example 1, and the specific preparation process is as follows:

[0111]

[0112] Synthesis of intermediate 344-1: A 100 mL three-necked round-bottom flask was placed with a stir bar and a reflux tube attached. Under nitrogen protection, the following starting materials were added sequentially: benzoxazole (1 mmol), 9-bromo-10-chloroanthracene (1.2 mmol), palladium acetate (0.05 mmol), cesium carbonate (2 mmol), and DMSO (10 mL). The mixture was cooled to 0°C, and then n-butyllithium (0.05 mmol) was slowly added dropwise. After the addition was complete, the mixture was slowly heated to 50°C and reacted for 14 hours. After the reaction was completed, the mixture was cooled to room temperature, quenched with saturated ammonium chloride aqueous solution, extracted with ethyl acetate, washed with saturated sodium chloride, and the organic phase was dried over anhydrous magnesium sulfate. The solvent was removed using a rotary evaporator. The crude product was separated by column chromatography (ethyl acetate: n-hexane = 1:50) to obtain intermediate 344-1 (yield 82%).

[0113] Synthesis of intermediate 344-2: A 100 mL three-necked round-bottom flask was placed with a stir bar and a reflux tube attached. Under nitrogen protection, intermediate 344-1 (1 mmol), diboronate (1.1 mmol), 1,4-dioxane (10 mL), Pd(dppf)Cl2 (0.03 mmol), and potassium acetate (2.5 mmol) were added sequentially. The mixture was heated to 100 °C and reacted for 5 hours. After the reaction was completed, the mixture was cooled to room temperature and extracted with ethyl acetate. The organic phase was dried over anhydrous magnesium sulfate, and the solvent was removed using a rotary evaporator. The crude product was separated by column chromatography (ethyl acetate: n-hexane = 1:50) to obtain intermediate 344-2 (yield 78%).

[0114] Synthesis of intermediate 344-A: A 100 mL three-necked round-bottom flask was placed with a stir bar and a reflux tube attached. Under nitrogen protection, intermediate 344-2 (1 mmol), 2,4-dichloro-6-phenyl-[1,3,5]triazine (0.9 mmol), Pd(dppf)Cl2 (0.03 mmol), potassium carbonate (2.5 mmol), and 1,4-dioxane / water (10 mL / 2 mL) were added sequentially. The mixture was heated to 90 °C and reacted for 5 hours. After the reaction was completed, the mixture was cooled to room temperature, filtered, and the filter cake was washed twice with deionized water and twice with tetrahydrofuran to obtain intermediate 344-A (yield 67%).

[0115] Synthesis of compound 344: A 100 mL three-necked round-bottom flask was placed with a stir bar and a reflux tube attached. Under nitrogen protection, intermediates 344-A (1 mmol), 2-B (1.1 mmol), Pd(dppf)Cl2 (0.03 mmol), potassium carbonate (2.5 mmol), and 1,4-dioxane / water (10 mL / 2 mL) were added sequentially. The mixture was heated to 90 °C and reacted for 5 hours. After the reaction was completed, the mixture was cooled to room temperature, filtered, and the filter cake was washed twice with deionized water and twice with ethanol. The crude product was then purified twice by recrystallization from o-dichlorobenzene to obtain compound 344 (yield 58%).

[0116] Elemental analysis: C 46 H 26 Theoretical values ​​for N4O2: C, 82.87; H, 3.93; N, 8.40; O, 4.80; Measured values: C, 82.90; H, 3.92; N, 8.38; HRMS(ESI) m / z [M+H]+: Theoretical value: 666.2056; Measured value: 667.1572.

[0117] Examples 9-12

[0118] The intermediates 247-A and 255-A in Examples 9 and 10 below were prepared in the same manner as 2-A above, except that the raw materials were different; the intermediates 289-A and 297-A in Examples 11 and 12 below can be prepared by conventional methods using the chemical formula in the general formula.

[0119] The preparation of the product in the following examples is the same as that of compound 2 above, except that the intermediate nA and the raw material B are different. The structure and yield of the raw material nA, B and the product are shown in Table 1 below; the elemental analysis results of the prepared compound are shown in Table 2.

[0120] Table 1

[0121]

[0122] Table 2

[0123]

[0124] Device Examples 1-14 and Device Comparative Examples 1-4

[0125] The organic electroluminescent devices in the device embodiments and device comparison examples have similar structures, such as... Figure 1 As shown, the organic electroluminescent device has the following layered structure stacked in sequence: substrate 1 / anode 2 / hole injection layer 3 (HIL) / hole transport layer 4 (HTL) / light-emitting layer 5 (EML) / electron transport layer 6 (ETL) / electron injection layer 7 (EIL), and finally cathode 8. The materials used to manufacture the organic electroluminescent device are as follows:

[0126]

[0127] The fabrication of the organic electroluminescent devices in Device Examples 1-14 and Device Comparative Examples 1-4 includes the following steps:

[0128] 1) Substrate cleaning:

[0129] The glass substrate coated with transparent ITO was ultrasonically treated in an aqueous cleaning agent (the composition and concentration of the aqueous cleaning agent: ethylene glycol solvent ≤10wt%, triethanolamine ≤1wt%), rinsed in deionized water, ultrasonically degreased in an acetone:ethanol mixed solvent (volume ratio 1:1), baked in a clean environment until all moisture was removed, and then cleaned with ultraviolet light and ozone.

[0130] 2) Evaporation of organic light-emitting functional layer:

[0131] The glass substrate with the anode layer was placed in a vacuum chamber and evacuated to a vacuum level of 1×10⁻⁶. -6 Up to 2×10 -4Pa, a mixture of NDP-9 and HT is vacuum-deposited on the above-mentioned anodic layer film, wherein the mass ratio of NDP-9 to HT is 3:97, as a hole injection layer, and the deposition thickness is 10 nm.

[0132] A hole transport layer (material HT) is deposited on the hole injection layer, with a film thickness of 80 nm.

[0133] The light-emitting layer is deposited on the hole transport layer. The specific preparation method is as follows: the light-emitting host material (the materials are shown in Table 1) and the guest material (piq)2Ir(acac) are vacuum deposited by co-evaporation, and the total film thickness is 38nm.

[0134] An electron transport layer is deposited on the light-emitting layer. The specific preparation method is as follows: the electron transport layer material is vacuum deposited by co-evaporation (the material is shown in Table 1), and the total film thickness is 30 nm.

[0135] An electron injection layer (LiQ material) was vacuum-deposited on the electron transport layer, with a total film thickness of 1 nm.

[0136] Al was deposited on the electron injection layer, with a total film thickness of 80 nm.

[0137] The parameters of each layer in the device, including its material and thickness, are shown in Table 3.

[0138] Table 3

[0139]

[0140]

[0141] The organic electroluminescent devices obtained in Device Examples 1-14 and Device Comparative Examples 1-4 were tested.

[0142] Test instruments: The current, voltage, brightness, emission spectrum and other characteristics of the device were tested simultaneously using a PR 650 spectral scanning luminance meter and a Keithley K 2400 digital source meter system;

[0143] Test conditions: Photoelectric property test conditions: current density 10 mA / cm² 2 .

[0144] Lifetime test: Current density 50mA / cm 2 The recording time (in hours) is recorded when the device brightness drops to 95% of its original brightness.

[0145] The device performance test results are shown in Table 4:

[0146] Table 4

[0147]

[0148]

[0149] As shown in Table 4, the compounds developed in this invention can significantly improve carrier injection efficiency, reduce interlayer energy level differences, and balance electron and hole transport rates, effectively improving the efficiency and extending the lifetime of organic light-emitting diodes (OLEDs). When organic electroluminescent materials are used as electron transport layer materials, the devices can exhibit lower driving voltage (below 4.5V), higher current efficiency (above 17Cd / A), and higher lifetime (above 100h); when organic electroluminescent materials are used as light-emitting layer materials, the devices can exhibit lower driving voltage (below 3.9V), higher current efficiency (above 20Cd / A), and higher lifetime (above 105h).

Claims

1. An organic electroluminescent compound, characterized by: having the structure: wherein L is selected from a direct bond, substituted or unsubstituted C6-C60aryl, and substituted or unsubstituted C3-C60heteroaryl; R 1 selected from halogen, cyano, substituted or unsubstituted C6-C60aryl, and substituted or unsubstituted C3-C60heteroaryl; each of the substituents of the substituted C6-C60 aryl, the substituted C3-C60 heteroaryl is independently selected from one or a combination of at least two of deuterium, halogen, cyano, C1-C12 alkyl, C3-C12 cycloalkyl, C6-C30 aryl, C3-C30 heteroaryl, C6-C60 arylamine, C3-C60 heteroarylamine.

2. The organic electroluminescence compound according to claim 1, characterized by: the formula I is selected from one of the following 1-1 to 1-10 structures:

3. The organic electroluminescence compound according to claim 1 or 2, characterized by: said R 1 selected from the group consisting of substituted or unsubstituted groups: phenyl, naphthyl, biphenyl, terphenyl, triphenylenyl, dimethylfluorenyl, diphenylfluorenyl, dibenzofuranyl, dibenzothiophenyl, benzonaphthofuranyl, benzonaphthothiophenyl; each of the substituents of the above-mentioned substituted groups is independently selected from one or a combination of at least two of deuterium, halogen, cyano, C1-C12 alkyl, C3-C12 cycloalkyl, C6-C30 aryl, C3-C30 heteroaryl, C6-C60 arylamine, C3-C60 heteroarylamine.

4. The organic electroluminescence compound according to claim 3, characterized by: the L is selected from a bond, substituted or unsubstituted phenylene, substituted or unsubstituted naphthylene, substituted or unsubstituted biphenylene, substituted or unsubstituted phenanthrylene, substituted or unsubstituted anthrylene; each of the substituents of the above-mentioned substituted groups is independently selected from one or a combination of at least two of deuterium, halogen, cyano, C1-C12 alkyl, C3-C12 cycloalkyl, C6-C30 aryl, C3-C30 heteroaryl, C6-C60 arylamine, C3-C60 heteroarylamine.

5. The organic electroluminescence compound according to claim 4, characterized by the formula I is selected from one of the following 1 to 365 structures:

6. An organic electroluminescent material, characterized by: The organic electroluminescence compound according to any one of claims 1 to 5.

7. An organic electroluminescent device comprising a cathode, an anode and an organic layer between the cathode and the anode, characterized in that: The organic layer comprises the organic electroluminescence compound according to any one of claims 1 to 5 or the organic electroluminescence material according to claim 6.

8. The organic electroluminescent device according to claim 7, characterized in that: The organic layer comprises an electron transport layer, the electron transport layer comprises the organic electroluminescence compound according to any one of claims 1 to 5 or the organic electroluminescence material according to any one of claim 6.

9. The organic electroluminescent device according to claim 7, characterized in that: The organic layer comprises a light-emitting layer, the material of the light-emitting layer comprises a host material and a guest material; the host material comprises the organic electroluminescence material as described in claim 6.

10. The organic electroluminescent device according to claim 9, characterized in that: The guest material comprises a phosphorescent dopant or a thermally activated delayed fluorescence compound, the phosphorescent dopant comprises a complex of a transition metal.

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