Oxazole organic compound containing dibenzofuran and application thereof

Abstract

The invention relates to the technical field of display, in particular to an oxazole organic compound containing dibenzofuran and application of the oxazole organic compound. The oxazole organic compound containing the dibenzofuran, provided by the invention, has the following structure shown in the specification: # imgabs0 #, so that an organic electroluminescent device containing the oxazole organic compound containing the dibenzofuran has relatively low driving voltage, relatively high luminous efficiency and relatively long service life.

Description

Technical Field

[0001] The present invention relates to the field of display technologies, and particularly relates to an oxazole-based organic compound containing dibenzofuran and its applications. Background Art

[0002] An organic electroluminescent device (OLED) is a device that converts electrical energy into light by applying electricity to an organic electroluminescent material, and generally has a structure including an anode, a cathode, and an organic layer between the anode and the cathode. The organic layer of the organic EL device can be composed of a hole injection layer, a hole transport layer, an electron blocking layer, a light-emitting layer (which includes a host material and a doping material), an electron buffer layer, a hole blocking layer, an electron transport layer, an electron injection layer, etc., and the materials used for the organic layer are classified into hole injection materials, hole transport materials, electron blocking materials, light-emitting materials, electron buffer materials, hole blocking materials, electron transport materials, electron injection materials, etc. according to their functions. In the organic EL device, due to the applied voltage, holes are injected from the anode into the light-emitting layer, electrons are injected from the cathode into the light-emitting layer, and high-energy excitons are formed by the recombination of holes and electrons. Through this energy, the organic light-emitting compound reaches an excited state, and light is emitted by the energy generated when the excited state of the organic light-emitting compound returns to the ground state, thereby generating luminescence.

[0003] The most important factor determining the luminous efficiency in an organic EL device is the light-emitting material. The light-emitting material must have a high quantum efficiency, as well as high electron and hole mobilities, and the formed light-emitting material layer must be uniform and stable. The light-emitting material is classified into a blue light-emitting material, a green light-emitting material, a red light-emitting material, and additionally a yellow light-emitting material or an orange light-emitting material according to the color of the emitted light. In addition, the light-emitting material can also be classified into a host material and a doping material according to its function.

[0004] However, the existing organic electroluminescent materials have low stability, and the matching degree of HOMO and LUMO energy levels with adjacent energy levels is poor, resulting in the problem of unbalanced carrier mobilities, causing problems such as a high driving voltage, low luminous efficiency, and short lifespan of the organic electroluminescent device containing the organic electroluminescent material, which severely limits the application of the organic electroluminescent device. Summary of the Invention

[0005] The object of the present invention is to overcome the problems that the existing organic electroluminescent materials have low stability, and the matching degree of HOMO and LUMO energy levels with adjacent energy levels is poor, resulting in unbalanced carrier mobilities, and further causing a high driving voltage, low luminous efficiency, and short lifespan of the organic electroluminescent device containing the organic electroluminescent material, and thus to provide an oxazole-based organic compound containing dibenzofuran and its applications.

[0006] In the present invention, the definitions of substituent terms are as follows:

[0007] As used in the present invention, the term "halogen" may include fluorine, chlorine, bromine, or iodine.

[0008] As used in the present invention, the term "C1-C30 alkyl" refers to a monovalent substituent derived from a straight-chain or branched-chain saturated hydrocarbon having 1 to 30 carbon atoms, examples of which include, but are not limited to, methyl, ethyl, propyl, isobutyl, sec-butyl, tert-butyl, pentyl, isopentyl, and hexyl.

[0009] As used in the present invention, the term "C3-C30 cycloalkyl" refers to a monocyclic hydrocarbon or polycyclic hydrocarbon derived from a ring backbone having 1 to 30 carbon atoms, and the cycloalkanes may include cyclopropyl, cyclobutyl, adamantyl, and the like.

[0010] In the present invention, aryl and arylene include monocyclic, polycyclic, or fused-ring aryl groups, the rings of which 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, anthryl, fluorenyl, spirobifluorenyl, and the like. Arylene groups include, but are not limited to, phenylene, biphenylene, terphenylene, naphthylene, phenanthrylene, anthrylene, fluorenylene, spirobifluorenylene, and the like.

[0011] In the present invention, the heteroaryl and heteroarylene include monocyclic, polycyclic or fused-ring heteroaryl, the rings of which can be interrupted by short non-aromatic units, and the heteroatoms include nitrogen, oxygen and sulfur. The heteroaryl includes but is not limited to furyl, phenylthio, pyrrolyl, imidazolyl, pyrazolyl, thiazolyl, thiadiazolyl, isothiazolyl, isoxazolyl, oxazolyl, oxadiazolyl, triazinyl, tetrazinyl, triazolyl, tetrazolyl, furazanyl, pyridyl, pyrazinyl, pyrimidinyl, pyridazinyl, benzofuryl, benzothienyl, isobenzofuryl, dibenzofuryl, dibenzothienyl, benzimidazolyl, benzothiazolyl, benzoisothiazolyl, benzoisoxazolyl, benzoxazolyl, isoindolyl, indolyl, indazolyl, benzothiadiazolyl, quinolinyl, isoquinolinyl, cinnolinyl, quinazolinyl, quinoxalinyl, carbazolyl, phenoxazinyl, phenothiazinyl, phenanthridinyl, benzodioxolyl, dihydroacridinyl, and their derivatives, etc.; the heteroarylene includes but is not limited to furylene, phenylthionylene, pyrrolylene, imidazolylene, pyrazolylene, thiazolylene, thiadiazolylene, isothiazolylene, isoxazolylene, oxazolylene, oxadiazolylene, triazinylene, tetrazinylene, triazolylene, tetrazolylene, furazanylene, pyridinylene, pyrazinylene, pyrimidinylene, pyridazinylene, benzofurylene, benzothienylene, isobenzofurylene, dibenzofurylene, dibenzothienylene, benzimidazolylene, benzothiazolylene, benzoisothiazolylene, benzoisoxazolylene, benzoxazolylene, isoindolylene, indolylene, indazolylene, benzothiadiazolylene, quinolinylene, isoquinolinylene, cinnolinylene, quinazolinylene, quinoxalinylene, carbazolylene, phenoxazinylene, phenothiazinylene, phenanthridinylene, benzodioxolylene, dihydroacridinylene, and their derivatives, etc.

[0012] As used in the present invention, the term "substituted" means that a hydrogen atom in a compound is replaced by another substituent. The position is not limited to a specific position as long as the hydrogen at that position can be replaced by a substituent. When there are two or more substituents, the two or more substituents can be the same or different.

[0013] As used in the present invention, unless otherwise specified, the hydrogen atom includes protium, deuterium and tritium.

[0014] In the present invention, when the number of carbon atoms in a group is limited, the number of carbon atoms is any integer within the defined range. For example, C6-C30 aryl means that the number of carbon atoms in the aryl can be any integer within the range of 6-60, such as 6, 8, 10, 13, 15, 17, 20, 22, 25 or 30, etc.

[0015] In the present invention, represents a connecting bond.

[0016] The solution adopted in the present invention is as follows:

[0017] The present invention provides an oxazole-based organic compound containing dibenzofuran, which has a structure shown in the following formula (1):

[0018]

[0019] Ar is selected from substituted or unsubstituted C6-C60 aryl, substituted or unsubstituted C6-C60 arylamino, substituted or unsubstituted C3-C60 heteroarylamino, substituted or unsubstituted C3-C30 heteroaryl;

[0020] L is selected from substituted or unsubstituted C6-C30 arylene, substituted or unsubstituted C3-C30 heteroarylene;

[0021] R is selected from hydrogen, deuterium, cyano, substituted or unsubstituted C6-C60 aryl, substituted or unsubstituted C3-C30 heteroaryl;

[0022] The substituents in the substituted C6-C60 aryl, substituted C6-C60 arylamino, substituted C3-C60 heteroarylamino, substituted C3-C30 heteroaryl, substituted C6-C30 arylene, and substituted C3-C30 heteroarylene are each independently selected from one or at least two combinations of deuterium, halogen, cyano, C1-C12 alkyl, C3-C12 cycloalkyl, C6-C30 aryl, C3-C30 heteroaryl, C6-C60 arylamino, and C3-C60 heteroarylamino.

[0023] Preferably, Ar is selected from substituted or unsubstituted C6-C25 aryl, substituted or unsubstituted C6-C25 arylamino, substituted or unsubstituted C3-C25 heteroarylamino, substituted or unsubstituted C3-C20 heteroaryl;

[0024] Among them, the substituents in the substituted C6-C25 aryl, substituted C6-C25 arylamino, substituted C3-C25 heteroarylamino, and substituted C3-C20 heteroaryl are each independently selected from one or at least two combinations of deuterium, halogen, cyano, C1-C12 alkyl, C3-C12 cycloalkyl, C6-C30 aryl, C3-C30 heteroaryl, C6-C60 arylamino, and C3-C60 heteroarylamino;

[0025] Preferably, Ar is selected from substituted or unsubstituted B groups, and the B groups are selected from the following groups: phenyl, naphthyl, biphenyl, phenanthryl, fluoranthenyl, -yl, terphenyl, triphenylene, phenylnaphthyl, naphthylphenyl, dimethylfluorenyl, spirobifluorenyl, diphenylfluorenyl, dibenzofuranyl, dinaphthothiophenyl, a group having the following structure:

[0026]

[0027] Among them, the substituents in the substituted B group are 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 arylamino, and C3-C60 heteroarylamino;

[0028] Preferably, Ar is selected from phenyl, naphthyl, biphenyl, anthryl, phenanthryl, terphenyl, phenylnaphthyl, naphthylphenyl, dimethylfluorenyl, diphenylfluorenyl, spirobifluorenyl, dibenzofuranyl, benzonaphthofuranyl, diphenylaminophenyl.

[0029] Preferably, R is selected from hydrogen, substituted or unsubstituted C6-C20 aryl; among them, the substituents of the substituted C6-C20 aryl are selected from hydrogen and C1-C6 alkyl;

[0030] Preferably, R is selected from hydrogen, substituted or unsubstituted phenyl.

[0031] Preferably, L is selected from substituted or unsubstituted C6-C15 arylene; among them, the substituents in the substituted C6-C15 arylene are each independently selected from one or a combination of at least two of deuterium, halogen, and C1-C62 alkyl;

[0032] Preferably, L is selected from phenylene, biphenylene, naphthylene;

[0033] Preferably, L is selected from phenylene, naphthylene.

[0034] Preferably, the formula (1) is selected from one of the structures shown in 1-1 to 1-6 below:

[0035]

[0036] The definition of Ar is the same as above.

[0037] It can be understood that for the structures shown in 1-1 to 1-6, L is selected from phenylene, which is connected at the "*" position. Due to the steric hindrance effect, the corresponding structure is more three-dimensional, thereby improving the hole transport performance of the compound and making the organic electroluminescent device containing the corresponding structure have better performance.

[0038] Preferably, the organic compound is selected from any one of N-1 to N-127 below:

[0039]

[0040]

[0041]

[0042]

[0043]

[0044]

[0045]

[0046] The present invention provides a light-emitting host material, including the oxazole-based organic compound containing dibenzofuran as described above.

[0047] Preferably, the light-emitting host material includes a first host material and a second host material, wherein the first host material is the oxazole-based organic compound containing dibenzofuran as described above; the second host material is an organic electroluminescent compound having the following structure of formula (2):

[0048]

[0049] In the formula (2), Ar1 is selected from substituted or unsubstituted C6-C60 aryl, substituted or unsubstituted C3-C60 heteroaryl;

[0050] The substituents in the substituted C6-C60 aryl and the substituted C3-C630 heteroaryl are each independently selected from one or at least two combinations of deuterium, halogen, cyano, C1-C12 alkyl, C3-C12 cycloalkyl, C6-C30 aryl, C3-C30 heteroaryl, C6-C60 arylamino, and C3-C60 heteroarylamino;

[0051] Preferably, Ar1 is selected from substituted or unsubstituted C6-C60 non-fused aryl, substituted or unsubstituted C3-C60 non-fused heteroaryl;

[0052] The substituents in the substituted C6-C60 non-fused aryl and the substituted C3-C60 non-fused heteroaryl are each independently selected from one or at least two combinations of deuterium, halogen, cyano, C1-C12 alkyl, C3-C12 cycloalkyl, C6-C30 aryl, C3-C30 heteroaryl, C6-C60 arylamino, and C3-C60 heteroarylamino;

[0053] Preferably, Ar1 is selected from substituted or unsubstituted C6-C20 non-fused aryl, substituted or unsubstituted C3-C20 non-fused heteroaryl;

[0054] The substituents in the substituted C6-C20 non-fused aryl group and the substituted C3-C20 non-fused heteroaryl group are each independently selected from one or a combination of at least two of deuterium, halogen, cyano, C1-C12 alkyl group, C3-C12 cycloalkyl group, C6-C30 aryl group, C3-C30 heteroaryl group, C6-C60 arylamino group, and C3-C60 heteroarylamino group;

[0055] Preferably, Ar1 is selected from substituted or unsubstituted A groups, and the A group is selected from one of the following groups: phenyl, biphenyl, terphenyl;

[0056] Wherein the substituents in the substituted A group are selected from deuterium, phenyl, and naphthyl;

[0057] Preferably, Ar1 is selected from phenyl, biphenyl, terphenyl, and naphthylphenyl. Preferably, the organic electroluminescent compound having the structure of formula (2) is selected from any one of M-1 to M-104 as follows:

[0058]

[0059]

[0060]

[0061]

[0062]

[0063] Preferably, the mass ratio of the first host material to the second host material is 9:1 - 1:9;

[0064] Preferably, the mass ratio of the first host material to the second host material is 2:8 - 8:2;

[0065] More preferably, the mass ratio of the first host material to the second host material is 3:7 - 7:3;

[0066] Further preferably, the mass ratio of the first host material to the second host material is 4:6 - 6:4.

[0067] The present invention also provides an organic electroluminescent material, comprising the above-mentioned oxazole organic compound containing dibenzofuran or the above-mentioned light-emitting host material.

[0068] The present invention provides an organic electroluminescent device, which includes a cathode, an anode, and an organic layer located between the cathode and the anode, and the organic layer contains the above-mentioned oxazole organic compound containing dibenzofuran or the above-mentioned light-emitting host material or the above-mentioned organic electroluminescent material;

[0069] Preferably, the organic layer includes one or more of a hole injection layer, a hole transport layer, a light-emitting layer, an electron transport layer, and an electron injection layer.

[0070] Preferably, the hole transport layer includes the oxazole-based organic compound containing dibenzofuran, the above-mentioned light-emitting host material, or the above-mentioned organic electroluminescent material.

[0071] Preferably, the light-emitting layer includes the oxazole-based organic compound containing dibenzofuran, the above-mentioned light-emitting host material, or the above-mentioned organic electroluminescent material.

[0072] The present invention also provides the application of the above-mentioned organic electroluminescent device in an optical fiber device, a lighting device, an electrophotographic photoreceptor device, a photoelectric converter, an organic solar cell, a switching element device, an organic light-emitting field effect transistor, an image sensor, or a dye laser.

[0073] Advantages of the present invention:

[0074] The oxazole-based organic compound containing dibenzofuran provided by the present invention is based on the structure of formula (1). Further limiting the types of substituents can improve the structural stability of the compound. Moreover, the HOMO and LUMO energy levels of the oxazole-based organic compound containing dibenzofuran have a high degree of matching with adjacent energy levels, making the carrier mobility of the oxazole-based organic compound containing dibenzofuran relatively balanced. As a result, the organic electroluminescent device containing the oxazole-based organic compound containing dibenzofuran has a lower driving voltage, a higher luminous efficiency, and a longer lifespan.

[0075] Furthermore, the oxazole-based organic compound containing dibenzofuran provided by the present invention has good electron transport performance and can be used as an electron transport material or a light-emitting material.

[0076] Furthermore, an organic electroluminescent material provided by the present invention includes an oxazole-based organic compound containing dibenzofuran based on the structure of formula (1). As a result, the organic electroluminescent device containing the organic electroluminescent material has a lower driving voltage, a higher luminous efficiency, and a longer lifespan. Description of the Drawings

[0077] In order to more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the following will briefly introduce the drawings required for use in the description of the specific embodiments or the prior art. Obviously, the drawings in the following description are some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on these drawings.

[0078] Figure 1 This is the structural diagram of the organic electroluminescent device in the device embodiment of the present invention;

[0079] 1 - Substrate; 2 - Anode; 3 - Hole injection layer; 4 - Hole transport layer; 5 - Light-emitting layer; 6 - Electron transport layer; 7 - Electron injection layer; 8 - Cathode. Detailed implementation manners

[0080] The following embodiments are provided to better further understand the present invention. They are not limited to the described best implementation manners and do not limit the content and protection scope of the present invention. Any product that is the same as or similar to the present invention obtained by anyone under the inspiration of the present invention or by combining the features of the present invention with those of other existing technologies falls within the protection scope of the present invention.

[0081] For those not specifying specific experimental steps or conditions in the embodiments, operations or conditions according to the conventional experimental steps described in the literature in this field can be carried out. For reagents or instruments not indicating the manufacturer, they are all conventional reagent products that can be obtained through commercial purchase.

[0082] The term "organic electroluminescent material" in the present disclosure means a material that can be used in an organic electroluminescent device and can contain at least one compound. If necessary, the organic electroluminescent material can be included in any layer constituting the organic electroluminescent device. For example, the organic electroluminescent material can be a hole injection material, a hole transport material, a hole assisting material, a light-emitting assisting material, an electron blocking material, a light-emitting material (including a host material and a dopant material), an electron buffering material, a hole blocking material, an electron transport material, an electron injection material, etc.

[0083] The term "multiple organic electroluminescent materials" in the present disclosure means one or more combinations of organic electroluminescent materials containing at least two compounds, and the materials can be included in any layer constituting the organic electroluminescent device. It can mean both the materials before being included in the organic electroluminescent device (e.g., before vapor deposition) and the materials after being included in the organic electroluminescent device (e.g., after vapor deposition). For example, the multiple organic electroluminescent materials can be a combination of at least two compounds, and the materials can be included in at least one of the following: hole injection layer, hole transport layer, hole assisting layer, light-emitting assisting layer, electron blocking layer, light-emitting layer, electron buffering layer, hole blocking layer, electron transport layer, and electron injection layer. The at least two compounds can be included in the same layer or different layers, and can be co-evaporated or co-evaporated, or can be evaporated individually.

[0084] In the present invention, the compound having the structure of formula (1) is prepared through the following synthetic route:

[0085] 1. Synthesis of Intermediate Nn-A: The reaction raw materials Nn-1 and Nn-2 undergo a Suzuki cross-coupling reaction, and the reaction formula is as follows:

[0086]

[0087] The synthesis of Intermediate N1-A includes the following steps:

[0088]

[0089] After purging the three-neck reaction flask equipped with a mechanical stirrer, thermometer, and condenser with nitrogen, 10 g of raw material N1-1 (36.63 mmol), 5.72 g of N1-2 (36.63 mmol), 0.85 g of tetrakis(triphenylphosphine)palladium(0) (0.73 mmol), 10.11 g of potassium carbonate (73.27 mmol), 70 mL of toluene, 30 mL of ethanol, and 30 mL of water were added in sequence. And the mixture was stirred at 65 °C for 2 hours. After the reaction was completed, the organic layer was extracted with ethyl acetate (EA), and the residual moisture was removed by using anhydrous sodium sulfate. The residue was dried and purified by column chromatography to obtain 10.06 g of Intermediate N1-A (yield 90%).

[0090] The synthesis of Intermediate N2-A is the same as that of N1-A, except that N2-2 is used instead of N1-2 to obtain Intermediate N2-A with a yield of 85%. The reaction is as follows:

[0091]

[0092] The synthesis of Intermediate N3-A is the same as that of N1-A, except that N3-2 is used instead of N1-2 to obtain Intermediate N3-A with a yield of 83%. The reaction is as follows:

[0093]

[0094] The synthesis of Intermediate N4-A is the same as that of N1-A, except that N2-1 is used instead of N1-1 to obtain Intermediate N4-A with a yield of 87%. The reaction is as follows:

[0095]

[0096] The synthesis of Intermediate N5-A is the same as that of N4-A, except that N2-2 is used instead of N1-2 to obtain Intermediate N5-A with a yield of 82%. The reaction is as follows:

[0097]

[0098] The synthesis of intermediate N6-A is the same as that of N4-A, except that N3-2 is used instead of N1-2 to obtain intermediate N6-A with a yield of 78%. The reaction is as follows:

[0099]

[0100] 2. Synthesis of compound N-n: Intermediate Nn-A and Nn-B undergo Buchwald-Hartwig cross-coupling reaction. The reaction formula is as follows:

[0101]

[0102] X is a halogen.

[0103] In the present invention, the compound with the structure shown in formula (2) is prepared through the following synthetic route:

[0104]

[0105] Intermediate raw materials A-n, B-n, and C-n can all be directly purchased or synthesized through conventional reaction paths and conditions by referring to the methods reported in the existing literature.

[0106] The specific structures of the intermediate raw materials used in the examples provided by the present invention are as follows:

[0107] The specific structure of B-n is:

[0108]

[0109] The specific structure of C-n is:

[0110]

[0111] Preparation of deuterated intermediate:

[0112]

[0113] In a clean 30 mL high-pressure reaction kettle, raw material C-2 (1 mmol), platinum dioxide (20% w / w), heavy water (5 mL), and decahydroquinoline (5 mL) are added in sequence. Nitrogen is bubbled for at least 10 minutes, the temperature is raised to 180 °C and the reaction is carried out for at least 16 hours. After the reaction is completed, the temperature is lowered to room temperature, and after extraction with ethyl acetate, the organic phase is dried with anhydrous magnesium sulfate, and the solvent is removed using a rotary evaporator to obtain a crude product. The crude product is repeated at least 2 times the above reaction process to ensure that the hydrogen on the aromatic ring is all deuterated. Finally, the crude product is separated by column chromatography (ethyl acetate: n-hexane = 1:50) to obtain intermediate C-2-D (yield 13%).

[0114] Example 1

[0115] This embodiment provides an oxazole-based organic compound N-1 containing dibenzofuran. The synthesis of the oxazole-based organic compound N-1 containing dibenzofuran specifically includes the following steps:

[0116]

[0117] After replacing the nitrogen in a three-necked reaction flask equipped with a mechanical stirrer, a thermometer, and a condenser, 10 g of intermediate N1-B (29.84 mmol), 9.56 g of N3-A (31.33 mmol), 0.27 g of tris(dibenzylideneacetone)dipalladium(0) (0.3 mmol), 0.24 g of 2-dicyclohexylphosphino-2',6'-dimethoxybiphenyl (0.06 mmol), 5.74 g of sodium tert-butoxide (59.68 mmol), and 100 mL of toluene were successively added, and the mixture was refluxed and stirred at 110 °C for 3 hours. After the reaction was completed, the organic layer was extracted with ethyl acetate, and the residual moisture was removed by using anhydrous sodium sulfate. The residue was dried and purified by column chromatography to obtain 14.21 g of the oxazole-based organic compound N-1 containing dibenzofuran (yield 78.8%).

[0118] Elemental analysis: C43H28N2O2; theoretical values: C, 85.41; H, 4.67; N, 4.63; O, 5.29; measured values: C, 85.43; H, 4.68; N, 4.61; HRMS(ESI) m / z [M+H]+: theoretical value: 604.22; measured value: 605.23.

[0119] Example 2

[0120] This embodiment provides an oxazole-based organic compound N-19 containing dibenzofuran. The synthesis of the oxazole-based organic compound N-19 containing dibenzofuran specifically includes the following steps:

[0121]

[0122] The synthesis steps are the same as those of N-1 in Example 1, except that N19-A is used instead of N1-B to obtain compound N-19 with a yield of 75.8%.

[0123] Elemental analysis: C45H28N2O2; theoretical values: C, 85.97; H, 4.49; N, 4.46; O, 5.09; measured values: C, 85.99; H, 4.51; N, 4.43; HRMS(ESI) m / z [M+H]+: theoretical value: 628.22; measured value: 628.99.

[0124] The preparation methods of Examples 3-16 are similar to those of Example 1. Specifically, the raw materials used and the products obtained in Examples 3-16 are shown in Table 1 below.

[0125] Table 1

[0126]

[0127]

[0128]

[0129]

[0130] The characterization data of the products obtained from the preparations of Examples 3 - 17 are shown in Table 2 as follows:

[0131] Table 2

[0132]

[0133]

[0134] Example 17

[0135] This example provides the organic electroluminescent compound M - 3 in the light - emitting host material. The synthesis of the organic electroluminescent compound M - 3 specifically includes the following steps:

[0136]

[0137] Take a 100 - milliliter three - necked round - bottom flask, place a magnetic stirrer bar in it and connect a reflux condenser above. Under nitrogen protection, successively add raw material A - 3 (1 mmol), 2,4 - dichloro - 6 - phenyl - 1,3,5 - triazine (1.2 mmol), Pd(dppf)Cl2 (0.03 mmol), potassium carbonate (2.5 mmol), 1,4 - dioxane / water (10 mL / 2 mL). Heat the mixture to 60 °C and react for 5 hours. After the reaction is completed, cool it to room temperature, quench it with saturated ammonium chloride aqueous solution, extract with ethyl acetate, dry the organic phase with anhydrous magnesium sulfate, remove the solvent using a rotary evaporator, and separate the crude product by column chromatography (ethyl acetate:n - hexane = 1:50) to obtain intermediate M - 3 - 1 (yield 61%).

[0138] Take a 100 mL three-necked round-bottom flask, add a magnetic stir bar and connect a reflux condenser. Under nitrogen protection, sequentially add intermediate M-3-1 (1 mmol), 4,4,5,5-tetramethyl-2-(naphtho[2,1-b]benzofuran-1-yl)-1,3,2-dioxaborolane, namely C-1 (1.2 mmol), Pd(dppf)Cl2 (0.03 mmol), potassium carbonate (2.5 mmol), 1,4-dioxane / water (10 mL / 2 mL). Heat the mixture to 90 °C and react for 5 hours. After the reaction is completed, cool the reaction mixture to room temperature, filter it by suction, wash the filter cake twice with deionized water and twice with ethanol. The obtained crude product is recrystallized and purified twice with o-dichlorobenzene to obtain compound M-3 (yield 42%).

[0139] Elemental analysis: C 41 H 25 N3. Theoretical values: C, 85.54; H, 4.38; N, 7.30; O, 2.78; Found values: C, 85.48; H, 4.50; N, 7.24; HRMS(ESI) m / z [M+H] + : Theoretical value: 575.20; Found value: 576.20.

[0140] Example 18

[0141] This example provides an organic electroluminescent compound M-54 in a light-emitting host material. The synthesis of the organic electroluminescent compound M-54 specifically includes the following steps:

[0142]

[0143] Take a 100 mL three-necked round-bottom flask, add a magnetic stir bar and connect a reflux condenser. Under nitrogen protection, sequentially add raw material A-54 (1 mmol), 2,4-dichloro-6-phenyl-1,3,5-triazine (1.2 mmol), Pd(dppf)Cl2 (0.03 mmol), potassium carbonate (2.5 mmol), 1,4-dioxane / water (10 mL / 2 mL). Heat the mixture to 60 °C and react for 5 hours. After the reaction is completed, cool the reaction mixture to room temperature, quench it with a saturated ammonium chloride aqueous solution, extract it with ethyl acetate, dry the organic phase with anhydrous magnesium sulfate, remove the solvent using a rotary evaporator, and separate the crude product by column chromatography (ethyl acetate: n-hexane = 1:50) to obtain intermediate M-54-1 (yield 45%).

[0144] Take a 100 mL three-necked round-bottom flask, add a magnetic stir bar and connect a reflux condenser. Under nitrogen protection, sequentially add intermediate M-54-1 (1 mmol), 4,4,5,5-tetramethyl-2-(naphtho[2,1-b]benzofuran-5-yl)-1,3,2-dioxaborolane, namely C-4 (1.2 mmol), Pd(dppf)Cl2 (0.03 mmol), potassium carbonate (2.5 mmol), 1,4-dioxane / water (10 mL / 2 mL). Heat the mixture to 90 °C and react for 5 hours. After the reaction is completed, cool the mixture to room temperature, filter it by suction, wash the filter cake twice with deionized water and twice with ethanol. The obtained crude product is recrystallized and purified twice with ortho-dichlorobenzene to obtain compound 54 (yield 46%).

[0145] Elemental analysis: C 41 H 25 N3. Theoretical values: C, 85.54; H, 4.38; N, 7.30; O, 2.78; Found values: C, 85.44; H, 4.54; N, 7.24; HRMS(ESI) m / z [M+H] + : Theoretical value: 575.20; Found value: 576.20.

[0146] Example 19

[0147] This example provides an organic electroluminescent compound M-58 in a light-emitting host material. The synthesis of the organic electroluminescent compound M-58 specifically includes the following steps:

[0148]

[0149] Take a 100 mL three-necked round-bottom flask, add a magnetic stir bar and connect a reflux condenser. Under nitrogen protection, sequentially add raw material A-58 (1 mmol), 2-([1,1'-biphenyl]-3-yl)-4,6-dichloro-1,3,5-triazine, namely B-2 (1.2 mmol), Pd(dppf)Cl2 (0.03 mmol), potassium carbonate (2.5 mmol), 1,4-dioxane / water (10 mL / 2 mL). Heat the mixture to 60 °C and react for 5 hours. After the reaction is completed, cool the mixture to room temperature, quench it with saturated ammonium chloride aqueous solution, extract it with ethyl acetate, dry the organic phase with anhydrous magnesium sulfate, remove the solvent using a rotary evaporator, and separate the crude product by column chromatography (ethyl acetate: n-hexane = 1:50) to obtain intermediate M-59-1 (yield 54%).

[0150] Take a 100 mL three-necked round-bottom flask, place a magnetic stir bar in it and connect a reflux condenser above. Under nitrogen protection, sequentially add intermediate M-59-1 (1 mmol), 4,4,5,5-tetramethyl-2-(naphtho[2,1-b]benzofuran-2-yl)-1,3,2-dioxaborolane, namely C-3 (1.2 mmol), Pd(dppf)Cl2 (0.03 mmol), potassium carbonate (2.5 mmol), 1,4-dioxane / water (10 mL / 2 mL). Heat the mixture to 90 °C and react for 5 hours. After the reaction is completed, cool it to room temperature, filter by suction, wash the filter cake twice with deionized water and twice with ethanol. The obtained crude product is recrystallized and purified twice with o-dichlorobenzene to obtain compound M-58 (yield 71%).

[0151] Elemental analysis: C 47 H 29 N3. Theoretical values: C, 86.61; H, 4.49; N, 6.45; O, 2.45; Measured values: C, 86.53; H, 4.59; N, 6.41; HRMS(ESI) m / z [M+H] + : Theoretical value: 651.23; Measured value: 652.24.

[0152] Example 20

[0153] This example provides the organic electroluminescent compound M-66 in the light-emitting host material. The synthesis of the organic electroluminescent compound M-66 specifically includes the following steps:

[0154]

[0155] Take a 100 mL three-necked round-bottom flask, place a magnetic stir bar in it and connect a reflux condenser above. Under nitrogen protection, sequentially add raw material A-66 (1 mmol), 2-([1,1':2',1'-terphenyl]-3-yl)-4,6-dichloro-1,3,5-triazine, namely B-5 (1.2 mmol), Pd(dppf)Cl2 (0.03 mmol), potassium carbonate (2.5 mmol), 1,4-dioxane / water (10 mL / 2 mL). Heat the mixture to 60 °C and react for 5 hours. After the reaction is completed, cool it to room temperature, quench with saturated ammonium chloride aqueous solution, extract with ethyl acetate, dry the organic phase with anhydrous magnesium sulfate, remove the solvent using a rotary evaporator, and separate the crude product by column chromatography (ethyl acetate: n-hexane = 1:50) to obtain intermediate M-66-1 (yield 49%).

[0156] Take a 100 mL three-necked round-bottom flask, place a magnetic stir bar in it and connect it to a reflux condenser. Under nitrogen protection, add intermediate M-66-1 (1 mmol), 4,4,5,5-tetramethyl-2-(naphtho[2,1-b]benzofuran-2-yl)-1,3,2-dioxaborolane, i.e., C-1 (1.2 mmol), Pd(dppf)Cl2 (0.03 mmol), potassium carbonate (2.5 mmol), 1,4-dioxane / water (10 mL / 2 mL) in sequence. Heat the mixture to 90 °C and react for 5 hours. After the reaction is completed, cool it to room temperature, filter it by suction, wash the filter cake twice with deionized water and twice with ethanol. The obtained crude product is recrystallized and purified twice with ortho-dichlorobenzene to obtain compound M-66 (yield 57%).

[0157] Elemental analysis: C 53 H 33 N3O. Theoretical values: C, 87.46; H, 4.57; N, 5.77; O, 2.20; Measured values: C, 87.33; H, 4.79; N, 5.68; HRMS(ESI) m / z [M+H] + : Theoretical value: 727.26; Measured value: 728.24.

[0158] The preparation methods of Examples 21 - 28 are similar to that of Example 1. Specifically, the raw materials used in Examples 21 - 28 and the obtained products are shown in Table 3 below.

[0159] Table 3

[0160]

[0161]

[0162] The characterization data of the products obtained in the preparation of Examples 21 - 28 are shown in Table 4:[[]]

[0163] Table 4

[0164]

[0165]

[0166] Device Example

[0167] This example provides an organic electroluminescent device, as Figure 1 shown, which includes an anode 2, a hole injection layer 3, a hole transport layer 4, a light-emitting layer 5, an electron transport layer 6, an electron injection layer 7, and a cathode 8 that are sequentially stacked on a substrate 1. Its device structure is: anode (indium tin oxide (ITO) coated glass substrate) / hole injection layer (HIL) / hole transport layer (HTL) / light-emitting layer (EML) / electron transport layer (ETL) / electron injection layer (EIL) / cathode (Al).

[0168] The materials for manufacturing the organic electroluminescent device are as follows:

[0169]

[0170] The preparation of the above-mentioned organic electroluminescent device includes the following steps:

[0171] 1) Substrate cleaning:

[0172] The glass substrate coated with transparent ITO is ultrasonically treated in an aqueous cleaning agent (the composition and concentration of the aqueous cleaning agent: ethylene glycol-based solvent ≤ 10 wt%, triethanolamine ≤ 1 wt%), then rinsed in deionized water, ultrasonically degreased in a mixed solvent of acetone and ethanol (the volume ratio of acetone to ethanol is 1:1), baked in a clean environment until all moisture is removed, and then cleaned with ultraviolet light and ozone.

[0173] 2) Organic layer preparation:

[0174] Transfer the ITO transparent substrate to an evaporation device and evacuate to 1×10 -6 to 2×10 -4 Pa, and sequentially evaporate a hole injection layer (HIL) / hole transport layer (HTL) / emitting layer (EML) / electron transport layer (ETL) / 1 nm electron injection layer (EIL) / thick cathode (Al) on the anode film.

[0175] Among them:

[0176] The material of the hole injection layer (HIL) is a mixture of NDP-9 and HT, and the specific mass ratio is shown in Table 5;

[0177] The material of the hole transport layer (HTL) is shown in Table 5;

[0178] The emitting layer (EML) is vacuum-evaporated by co-evaporation. The material of the emitting layer includes a host material and a guest material, where the guest material is (piq)2Ir(acac), and the specific material of the host material and its ratio to the guest material are shown in Table 5;

[0179] The material of the electron transport layer (ETL) is shown in Table 5;

[0180] The material of the electron injection layer (EIL) is LiQ;

[0181] The cathode is aluminum;

[0182] Some layers of the organic electroluminescent device, their materials and thicknesses are shown in Table 5

[0183] Table 5

[0184]

[0185]

[0186]

[0187]

[0188] The examples in the table represent device examples, and the comparative examples in the table are device comparative examples.

[0189] Test Example

[0190] The organic light-emitting devices obtained from Device Example 1-19 and Comparative Example 1-4 in the device examples were tested.

[0191] Instrument: The characteristics of the device such as current, voltage, brightness, and emission spectrum were synchronously tested using a PR 650 spectral scanning luminance meter and a Keithley K 2400 digital source meter system;

[0192] Test conditions: Optoelectronic characteristic test conditions: The current density was 10 mA / cm2.

[0193] Lifetime test: The current density was 50 mA / cm2, and the time (in hours) was recorded when the device brightness decreased to 95% of the original brightness.

[0194] The test results of the device performance are shown in Table 6:

[0195] Table 6

[0196]

[0197]

[0198] The examples in the table represent device examples, and the comparative examples in the table are device comparative examples.

[0199] Obviously, the above examples are merely illustrations for clear explanation and not limitations on the implementation manners. For those of ordinary skill in the art, other different forms of changes or modifications can be made based on the above description. It is not necessary and impossible to list all the implementation manners here. And the obvious changes or modifications derived therefrom are still within the protection scope of the present invention.

Claims

1. An oxazole-based organic compound containing dibenzofuran, characterized in that, It has the structure shown in the following formula (1): Ar is selected from substituted or unsubstituted C6-C60 aryl, substituted or unsubstituted C6-C60 arylamino, substituted or unsubstituted C3-C60 heteroarylamino, substituted or unsubstituted C3-C30 heteroaryl; L is selected from substituted or unsubstituted C6-C30 arylene, substituted or unsubstituted C3-C30 heteroarylene; R is selected from hydrogen, deuterium, cyano, substituted or unsubstituted C6-C60 aryl, substituted or unsubstituted C3-C30 heteroaryl; The substituents in the substituted C6-C60 aryl, substituted C6-C60 arylamino, substituted C3-C60 heteroarylamino, substituted C3-C30 heteroaryl, substituted C6-C30 arylene, substituted C3-C30 heteroarylene are each independently selected from deuterium, halogen, cyano, C1-C12 alkyl, C3-C12 cycloalkyl, C6-C30 aryl, C3-C30 heteroaryl, C6-C60 arylamino, C3-C60 heteroarylamino, or a combination of one or at least two thereof.

2. The oxazole-based organic compound containing dibenzofuran according to claim 1, characterized in that, Ar is selected from substituted or unsubstituted C6-C25 aryl, substituted or unsubstituted C6-C25 arylamino, substituted or unsubstituted C3-C25 heteroarylamino, substituted or unsubstituted C3-C20 heteroaryl; Among them, the substituents in the substituted C6-C25 aryl, substituted C6-C25 arylamino, substituted C3-C25 heteroarylamino, substituted C3-C20 heteroaryl are each independently selected from deuterium, halogen, cyano, C1-C12 alkyl, C3-C12 cycloalkyl, C6-C30 aryl, C3-C30 heteroaryl, C6-C60 arylamino, C3-C60 heteroarylamino, or a combination of one or at least two thereof; Preferably, Ar is selected from substituted or unsubstituted B groups, and the B groups are selected from the following groups: phenyl, naphthyl, biphenyl, phenanthryl, fluoranthenyl, yl, terphenyl, triphenylene, phenylnaphthyl, naphthylphenyl, dimethylfluorenyl, spirobifluorenyl, diphenylfluorenyl, dibenzofuranyl, dinaphthothiophenyl, a group having the structure shown below: Among them, the substituents in the substituted B group are selected from deuterium, halogen, cyano, C1-C12 alkyl, C3-C12 cycloalkyl, C6-C30 aryl, C3-C30 heteroaryl, C6-C60 arylamino, C3-C60 heteroarylamino, or a combination of one or at least two thereof; Preferably, Ar is selected from phenyl, naphthyl, biphenyl, anthryl, phenanthryl, terphenyl, phenylnaphthyl, naphthylphenyl, dimethylfluorenyl, diphenylfluorenyl, spirobifluorenyl, dibenzofuranyl, benzonaphthofuranyl, diphenylaminophenyl.

3. The oxazole-based organic compound containing dibenzofuran according to claim 1 or 2, characterized in that, R is selected from hydrogen, substituted or unsubstituted C6-C20 aryl; among them, the substituents of the substituted C6-C20 aryl are selected from hydrogen, C1-C6 alkyl; Preferably, R is selected from hydrogen, substituted or unsubstituted phenyl.

4. The oxazole-based organic compound containing dibenzofuran according to any one of claims 1-3, characterized in that, L is selected from substituted or unsubstituted C6-C15 arylene; among them, the substituents in the substituted C6-C15 arylene are each independently selected from deuterium, halogen, C1-C62 alkyl, or a combination of one or at least two thereof; Preferably, L is selected from phenylene, biphenylene, naphthylene; Preferably, L is selected from phenylene, naphthylene.

5. The oxazole-based organic compound containing dibenzofuran according to any one of claims 1-4, characterized in that, The formula (1) is selected from one of the structures shown in the following 1-1 to 1-6: The definition of Ar is the same as that in claim 1.

6. The oxazole-based organic compound containing dibenzofuran according to any one of claims 1-5, characterized in that, The organic compound is selected from any one of the following N-1 to N-127:

7. A light-emitting host material, characterized in that, It includes the oxazole-based organic compound containing dibenzofuran according to any one of claims 1-6.

8. The light-emitting host material according to claim 7, wherein The light-emitting host material includes a first host material and a second host material, wherein the first host material is an oxazole-based organic compound containing dibenzofuran as described in any one of claims 1-6; the second host material is an organic electroluminescent compound having the structure of formula (2) as follows: In the formula (2), Ar1 is selected from substituted or unsubstituted C6-C60 aryl groups, substituted or unsubstituted C3-C60 heteroaryl groups; The substituents in the substituted C6-C60 aryl groups and the substituted C3-C630 heteroaryl groups are each independently selected from one or at least two combinations of deuterium, halogen, cyano, C1-C12 alkyl groups, C3-C12 cycloalkyl groups, C6-C30 aryl groups, C3-C30 heteroaryl groups, C6-C60 arylamino groups, and C3-C60 heteroarylamino groups; Preferably, Ar1 is selected from substituted or unsubstituted C6-C60 non-fused aryl groups, substituted or unsubstituted C3-C60 non-fused heteroaryl groups; The substituents in the substituted C6-C60 non-fused aryl groups and the substituted C3-C60 non-fused heteroaryl groups are each independently selected from one or at least two combinations of deuterium, halogen, cyano, C1-C12 alkyl groups, C3-C12 cycloalkyl groups, C6-C30 aryl groups, C3-C30 heteroaryl groups, C6-C60 arylamino groups, and C3-C60 heteroarylamino groups; Preferably, Ar1 is selected from substituted or unsubstituted C6-C20 non-fused aryl groups, substituted or unsubstituted C3-C20 non-fused heteroaryl groups; The substituents in the substituted C6-C20 non-fused aryl groups and the substituted C3-C20 non-fused heteroaryl groups are each independently selected from one or at least two combinations of deuterium, halogen, cyano, C1-C12 alkyl groups, C3-C12 cycloalkyl groups, C6-C30 aryl groups, C3-C30 heteroaryl groups, C6-C60 arylamino groups, and C3-C60 heteroarylamino groups; Preferably, Ar1 is selected from substituted or unsubstituted A groups, and the A group is selected from one of the following groups: phenyl, biphenyl, terphenyl; Wherein the substituents in the substituted A groups are selected from deuterium, phenyl, and naphthyl; Preferably, Ar1 is selected from phenyl, biphenyl, terphenyl, and naphthylphenyl.

9. The light-emitting host material according to claim 7 or 8, characterized in that, The mass ratio of the first host material to the second host material is 9:1 - 1:9; Preferably, the mass ratio of the first host material to the second host material is 2:8 - 8:2; More preferably, the mass ratio of the first host material to the second host material is 3:7 - 7:3; Further preferably, the mass ratio of the first host material to the second host material is 4:6 - 6:

4.

10. An organic electroluminescent material, characterized in that, It includes an oxazole-based organic compound containing dibenzofuran as described in any one of claims 1-6 or a light-emitting host material as described in any one of claims 7-9.

11. An organic electroluminescent device, characterized in that, The organic electroluminescent device includes a cathode, an anode, and an organic layer located between the cathode and the anode. The organic layer contains the oxazole-based organic compound containing dibenzofuran according to any one of claims 1-6, or the light-emitting host material according to any one of claims 7-9, or the organic electroluminescent material according to claim 10; Preferably, the organic layer includes one or more of a hole injection layer, a hole transport layer, a light-emitting layer, an electron transport layer, and an electron injection layer. Preferably, the hole transport layer contains the oxazole-based organic compound containing dibenzofuran according to any one of claims 1-6, or the light-emitting host material according to any one of claims 7-9, or the organic electroluminescent material according to claim 10; Preferably, the light-emitting layer contains the oxazole-based organic compound containing dibenzofuran according to any one of claims 1-6, or the light-emitting host material according to any one of claims 7-9, or the organic electroluminescent material according to claim 10.

12. Application of the organic electroluminescent device according to claim 11 in an optical fiber device, a lighting device, an electrophotographic photoreceptor device, a photoelectric converter, an organic solar cell, a switching element device, an organic light-emitting field effect transistor, an image sensor, or a dye laser.

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