Carbazole compound, intermediate and organic electroluminescent device

Abstract

The invention provides a carbazole compound, an intermediate and an organic electroluminescent device. The carbazole compound has a structure as shown in a formula I. The structure of the carbazole compound is designed, so that the carbazole compound is suitable for being used as a main body material of a light-emitting layer of the organic light-emitting device, and the organic light-emitting device has relatively high current efficiency and relatively long service life.

Description

Technical Field

[0001] The invention belongs to the technical field of organic electroluminescent materials, and in particular relates to a carbazole compound, an intermediate and an organic electroluminescent device. Background Art

[0002] The structure of an organic electroluminescent device is specifically: an anode, a cathode, and an organic layer between the two. In order to improve the efficiency and stability of an organic electroluminescent element, the organic material layer includes multiple layers with different materials, such as a hole injection layer (HIL), a hole transport layer (HTL), a hole blocking layer, a light-emitting layer, an electron transport layer (ETL), and an electron injection layer (EIL). Currently, organic electroluminescence has become a mainstream display technology, and accordingly, various new OLED materials have also been developed.

[0003] In order to meet people's higher requirements for OLED devices, the field is in urgent need of developing more types of materials to improve the performance of OLED devices in terms of current efficiency, life span, etc. Summary of the invention

[0004] In view of the shortcomings of the prior art, the present invention aims to provide a carbazole compound, an intermediate and an organic electroluminescent device. In the present invention, the structure of the carbazole compound is designed to make it suitable for use as a host material of the phosphorescent light-emitting layer of the organic electroluminescent device, so that the organic electroluminescent device has a lower driving voltage, a higher current efficiency and a longer life.

[0005] To achieve this object, the present invention adopts the following technical solutions:

[0006] In a first aspect, the present invention provides a carbazole compound having a structure shown in the following formula I:

[0007]

[0008] Ar1 and Ar2 are each independently selected from any one of a C6-C40 aryl group or a C6-C30 heteroaryl group;

[0009] The hydrogen atoms in the compound of formula I may each independently be substituted by at least one of a deuterium atom (-D), -F, -CN, a C6-C20 aryl group, a triphenylmethyl group, a triphenylsilyl group, a C1-C12 alkyl group or a C1-C12 alkoxy group.

[0010] In the compound of formula I provided by the present invention, Ar2 and the carbazole ring on the triphenylene group are in ortho-substituted positions, the two rings are in an approximately parallel state, the spatial structure is more regular, the charge transfer performance is better, and it is more suitable for use as a main material for the light-emitting layer of an organic electroluminescent device.

[0011] In the present invention, the structure of the carbazole compound is designed to make it suitable as the main material of the phosphorescent light-emitting layer of the organic electroluminescent device, so that the organic electroluminescent device has a lower driving voltage, a higher current efficiency and a longer life.

[0012] The compound of the present invention connects Ar2 and carbazole groups to the triphenylene group at the same time, and the two groups are in a nearly parallel state, the spatial structure is more regular, and the charge transfer performance is better. The group increases the thermal stability of the molecule, improves the state after film formation, and is more suitable for use as the main material of the light-emitting layer of an organic electroluminescent device. The resulting organic electroluminescent device has higher current efficiency, longer life and lower voltage.

[0013] In the present invention, C6-C40 can be C6, C8, C10, C12, C16, C20, C24, C28, C30, C32, C36 or C40, etc.

[0014] C6-C30 can be C6, C8, C10, C12, C16, C20, C24, C28 or C30, etc.

[0015] C6-C20 can be C6, C8, C10, C12, C16 or C20, etc.

[0016] C1-C12 can be C1, C2, C3, C4, C5, C6, C7, C8, C9, C10, C11 or C12.

[0017] It should be noted that, in the present invention, "-D" represents a deuterium atom, and the same applies hereinafter.

[0018] The following are preferred technical solutions of the present invention, but are not intended to limit the technical solutions provided by the present invention. Through the following preferred technical solutions, the objectives and beneficial effects of the present invention can be better achieved and realized.

[0019] As a preferred technical solution of the present invention, the carbazole compound has any one of the structures shown in the following formula I-1, formula I-2 or formula I-3:

[0020]

[0021] Wherein, Ar1 and Ar2 in the compound of formula I-1, the compound of formula I-2 or the compound of formula I-3 are each independently selected from any one of C6-C40 aryl or C6-C30 heteroaryl;

[0022] The hydrogen atoms in the compound of formula I-1, the compound of formula I-2 or the compound of formula I-3 can each independently be substituted by at least one of a deuterium atom (-D), -F, -CN, a C6-C20 aryl group, a triphenylmethyl group, a triphenylsilyl group, a C1-C12 alkyl group or a C1-C12 alkoxy group.

[0023] As a preferred technical solution of the present invention, the C6-C40 aromatic group is selected from any one or a combination of at least two of phenyl, biphenyl, terphenyl, naphthyl, anthracenyl, phenanthryl, fluorenyl, benzofluorenyl, dibenzofluorenyl, naphthfluoroenyl, pyrene, peryl, spirofluorenyl, triphenylene, fluoranthenyl, hydrogenated benzanthryl, indenofluorenyl, benzoindenofluorenyl, dibenzoindenofluorenyl, naphthfluoroenyl, tetraphenylmethane or benzonaphthofluorenyl.

[0024] As a preferred technical solution of the present invention, the C6-C30 heteroaryl group is selected from any one of carbazolyl, dibenzothiophenyl, dibenzofuranyl, naphthiobenzofuranyl, naphthiobenzothiophenyl, dinaphthofuranyl, and dinaphthothiophenyl, or a combination of at least two thereof.

[0025] Preferably, the C6-C20 aryl group is selected from any one of phenyl, naphthyl, biphenyl, anthracenyl, phenanthryl, fluorenyl, triphenylene or fluoranthene.

[0026] Preferably, the C1-C12 alkyl group is selected from any one of methyl, ethyl, propyl, n-butyl, tert-butyl, cyclopentyl, cyclohexyl, octyl and adamantyl.

[0027] Preferably, the C1-C12 alkoxy group is selected from any one of methoxy, ethoxy, propoxy, butoxy, pentyloxy, hexyloxy and octyloxy.

[0028] As a preferred technical solution of the present invention, Ar1 and Ar2 are each independently selected from any one or a combination of at least two of phenyl, carbazolyl, biphenyl, 9,9-dimethylfluorenyl, naphthyl, triphenylene, fluoranthene, indenofluorenyl, dibenzofuranyl, dibenzothienyl, naphthiobenzofuranyl or naphthiobenzothienyl.

[0029] Preferably, Ar1 and Ar2 are each independently selected from at least one of phenyl, carbazolyl, naphthyl, 9,9-dimethylfluorenyl, dibenzothiophenyl, biphenyl, dibenzofuranyl, triphenylene or fluoranthene.

[0030] Preferably, Ar1 and Ar2 are each independently selected from at least one of phenyl, naphthyl, biphenyl, dibenzofuranyl, dibenzothiophenyl and carbazole.

[0031] As a preferred technical solution of the present invention, the hydrogen atoms in the compound of formula I can be independently replaced by at least one of -D, -F, -CN, phenyl, naphthyl, biphenyl, triphenylmethyl, triphenylsilyl, methyl, ethyl, propyl, butyl, methoxy, ethoxy, propoxy or butoxy.

[0032] Preferably, the hydrogen atoms in the compound of formula I can be independently substituted by at least one of -D, -F, -CN, phenyl, naphthyl, methyl, ethyl, tert-butyl, methoxy, ethoxy and propoxy.

[0033] As a preferred technical solution of the present invention, the carbazole compound is selected from any one of the following substituted or unsubstituted compounds:

[0034]

[0035]

[0036]

[0037] The substitution means that the hydrogen atoms in the above carbazole compounds can be independently replaced by deuterium atoms. Preferably, the carbazole compound is selected from any one of the following compounds:

[0038]

[0039]

[0040] It should be noted that the present invention does not have any special restrictions on the preparation method of the above-mentioned carbazole compounds, and the commonly used preparation methods in the art are applicable. The preparation method of the compound of formula I provided by the present invention is illustrated as follows:

[0041]

[0042] Ar1 and Ar2 have the same meanings as above;

[0043] X1 and X2 are each independently selected from any one of -F, -Cl, -Br or -I;

[0044] The hydrogen atoms in the compound of formula MA-1, the compound of formula MA-2, the compound of formula MA-3, the compound of formula MA, and the compound of formula I can each independently be substituted by at least one of -D, -CN, -F, C6-C20 aryl, C6-C30 heteroaryl, C1-C12 alkyl, or C1-C12 alkoxy.

[0045] In a second aspect, the present invention provides an intermediate, wherein the intermediate comprises a compound having a structure shown in the following formula MA:

[0046]

[0047] Wherein, Ar2 has the same definition as above;

[0048] X1 is selected from any one of -F, -Cl, -Br or -I;

[0049] The hydrogen atoms in the compound of formula MA may each independently be substituted by at least one of -D, -CN, -F, C6-C20 aryl, C6-C30 heteroaryl, C1-C12 alkyl or C1-C12 alkoxy.

[0050] Preferably, the intermediate includes the following compounds:

[0051]

[0052] In a third aspect, the present invention provides an organic electroluminescent device, the organic electroluminescent device comprising an anode, a cathode and an organic thin film layer disposed between the anode and the cathode;

[0053] The organic thin film layer material includes the carbazole compound as described in the first aspect.

[0054] As a preferred technical solution of the present invention, the organic thin film layer includes a light-emitting layer, and the main material of the light-emitting layer includes the carbazole compound as described in the first aspect.

[0055] Preferably, the light-emitting layer is a phosphorescent light-emitting layer.

[0056] As a preferred technical solution of the present invention, the organic electroluminescent device is a green organic electroluminescent device.

[0057] The luminescent layer in the present invention includes a luminescent layer main material and a doping material, wherein the doping material is also called a dye or a phosphorescent luminescent material. The luminescent layer main material can be a single compound or a mixture of two or more compounds.

[0058] The light-emitting layer includes a phosphorescent light-emitting layer, and the phosphorescent light-emitting layer includes a green phosphorescent light-emitting layer, a red phosphorescent light-emitting layer, a yellow phosphorescent light-emitting layer, and a blue phosphorescent light-emitting layer.

[0059] The volume percentage of the main material in the phosphorescent layer is 60% to 99.9% (for example, it can be 60%, 65%, 70%, 75%, 80%, 85%, 90%, 95%, 98% or 99.9%, etc.), preferably 70% to 99.5%, and more preferably 85% to 95%.

[0060] In the present invention, the doping material of the light-emitting layer may be a phosphorescent material, which is also called a triplet light-emitting material, and refers to the light emitted by a substance from a triplet excited state. The specific selection of the phosphorescent material in the present invention is not particularly limited, and the doping materials of the light-emitting layer commonly used in the art are applicable, including but not limited to: a compound having a structure shown in the following formula PD:

[0061]

[0062] Wherein, M is selected from any one of Ir, Pt, Pd, Os, Ti, Zr, Hf, Eu, Tb, Tm, Cu or Au;

[0063] Y1-Y4 are each independently selected from carbon or nitrogen;

[0064] Y1 and Y2 can be connected by a single bond or a double bond, and Y3 and Y4 can be connected by a single bond or a double bond;

[0065] Cy1 and Cy2 are each independently selected from phenyl, naphthyl, fluorenyl, spirofluorenyl, indenyl, pyrrolyl, thienyl, furanyl, imidazolyl, pyrazolyl, thiazolyl, isothiazolyl, pyridyl, pyrazinyl, pyrimidinyl, pyridazinyl, quinolyl, isoquinolyl, benzoquinolyl, quinoxalinyl, quinazolinyl, carbazolyl, benzimidazolyl, benzofuranyl, benzothienyl, isobenzothienyl, benzimidazolyl, benzoxazolyl, triazolyl, tetrazolyl, oxadiazolyl, triazine, dibenzothienyl, N-heterocarbazolyl, wherein Cy1 and Cy2 may be optionally linked to each other via a single bond or an organic linking group;

[0066] Any two ligands of M, or more than two ligands, may be connected by a single bond or a double bond, or may be bridged by O or S, or may be connected by any chemical group or chemical structure to form a structural form that conforms to chemical principles;

[0067] R 91 and R 92each independently selected from -H, -D, -F, -Cl, -Br, -I, hydroxyl, cyano, nitro, amino, amidino, hydrazine, hydrazone, carboxylic acid, carboxylate, sulfonic acid, sulfonate, phosphoric acid, phosphate, -SF5, substituted or unsubstituted C1-C60 (e.g., C1, C5, C10, C15, C20, C25, C30, C35, C40, C45, C50, C55 or C60, etc.) alkyl, substituted or unsubstituted C2-C6 C2-C60 (for example, C2, C5, C10, C15, C20, C25, C30, C35, C40, C45, C50, C55 or C60, etc.) alkynyl, substituted or unsubstituted C1-C60 (for example, C1, C5, C10, C15, C20, C25, C30, C35, C40, C45, C50, C55 or C60, etc.) C2-C10 (for example, C2, C3, C4, C5, C6, C7, C8, C9 or C10) heterocycloalkyl, substituted or unsubstituted C6-C60 (for example, C6, C12, C15, C18, C24, C30, C32, C36, C40, C42, C54 or C60) aryl, substituted or unsubstituted C6-C60 (for example, C2, C3, C4, C5, C6, C7, C8, C9 or C10) For example, it can be any one of C6, C12, C15, C18, C24, C30, C32, C36, C40, C42, C54 or C60) aryloxy, substituted or unsubstituted C6-C60 (for example, it can be C6, C12, C15, C18, C24, C30, C32, C36, C40, C42, C54 or C60) arylthio, substituted or unsubstituted monovalent non-aromatic fused polycyclic group, and substituted or unsubstituted monovalent non-aromatic fused heteropolycyclic group.

[0068] a1 and a2 are each independently an integer selected from 1-5, for example, 1, 2, 3, 4 or 5;

[0069] b is an integer selected from 0-4, for example, 0, 1, 2, 3 or 4;

[0070] a is selected from 1, 2 or 3;

[0071] L1 is a monovalent organic ligand, a divalent organic ligand or a trivalent organic ligand.

[0072] Preferably, the compound of formula PD is selected from any one of the following compounds:

[0073]

[0074]

[0075]

[0076]

[0077]

[0078]

[0079] In the present invention, the organic thin film layer includes a hole layer, and the hole layer includes a hole injection layer, a hole transport layer and an electron blocking layer.

[0080] The hole injection layer material includes a P-type dopant. The P-type dopant refers to a dopant that coexists with the hole injection layer material in the OLED device and can oxidize the hole injection layer material, thereby acting as an electron acceptor and promoting the movement of holes in the hole injection layer to the anode. In the present invention, the difference between the absolute value of the LUMO of the P-type dopant and the absolute value of the HOMO of the hole layer material is greater than -0.2V, preferably greater than -0.1eV, more preferably greater than 0eV, more preferably greater than 0.1eV, and more preferably greater than 0.2eV.

[0081] The P-type dopant is present in the hole injection layer in a volume percentage of 1% to 10% (e.g., 1%, 2%, 4%, 6%, 8% or 10%). In the present invention, there is no particular limitation on the type of the P-type dopant, and illustratively, the compounds D-1 to D-13 disclosed in CN113728453A or the compounds HI-1 to HI-9 described below can be selected:

[0082]

[0083]

[0084] In the present invention, the hole layer material (including the hole injection layer, the hole transport layer and the electron blocking layer) has a structure shown in the following formula HT-GH4:

[0085]

[0086] Among them, L 41 is selected from a single bond, a C6-C40 (e.g., C6, C8, C10, C12, C16, C20, C24, C28, C30, C32, C36, or C40, etc.) aryl, or a C6-C20 (e.g., C6, C8, C10, C12, C16, or C20, etc.) heteroaryl;

[0087] Ar 41 ,Ar42 Each is independently selected from C6-C40 (for example, C6, C8, C10, C12, C16, C20, C24, C28, C30, C32, C36 or C40, etc.) aryl, C6-C20 (for example, C6, C8, C10, C12, C16 or C20, etc.) heteroaryl;

[0088] X is selected from CR 41 R 42 or NR 43 , where R 41 , R 42 , R 43 are each independently selected from substituted or unsubstituted phenyl (the substituted substituent is selected from C1-C6 (for example, C1, C2, C3, C4, C5 or C6) alkyl, C1-C6 (for example, C1, C2, C3, C4, C5 or C6) alkoxy, naphthyl, triphenylene, fluoranthene, 9,9-dimethylfluorenyl, biphenyl, substituted or unsubstituted group (the substituted substituent is phenyl), substituted or unsubstituted dibenzothienyl (the substituted substituent is phenyl), substituted thienyl, C1-C6 (for example, C1, C2, C3, C4, C5 or C6) alkyl, any one of R 41 , R 42 They can be linked to form rings via single bonds.

[0089] The compound of formula HT-GH4 is selected from any one of the following compounds:

[0090]

[0091]

[0092]

[0093] In the present invention, the hole layer material (including the hole injection layer, the hole transport layer and the electron blocking layer) also includes a compound having a structure shown in the following formula IA or a compound having a structure shown in the following formula IB:

[0094]

[0095] Wherein, L is selected from any one of C6-C40 (for example, C6, C8, C10, C12, C16, C20, C24, C28, C30, C32, C36 or C40, etc.) arylene, dibenzofuranyl or dibenzothiophenyl;

[0096] m is selected from an integer between 0 and 4 (for example, it can be 0, 1, 2, 3 or 4), and n is selected from 0 or 1;

[0097] Ar is selected from any one of triphenylene, fluoranthenylene, dibenzofuranylene or dibenzothiophenylene;

[0098] Ar1 and Ar2 are each independently selected from any one of a C6-C40 (e.g., C6, C8, C10, C12, C16, C20, C24, C28, C30, C32, C36 or C40, etc.) aryl group, dibenzofuran or dibenzothiophenyl group;

[0099] Ar1 and Ar, Ar2 and Ar, and Ar1 and Ar2 can each independently be connected or bridged by a single bond, O, S, CR1R2, or NR.

[0100] R, R1, and R2 are each independently selected from any one of a C1-C20 (e.g., C1, C2, C4, C6, C8, C10, C12, C14, C16, C18, or C20, etc.) alkyl group, a C6-C40 (e.g., C6, C8, C10, C12, C16, C20, C24, C28, C30, C32, C36, or C40, etc.) aryl group, a dibenzofuranyl group, or a dibenzothiophenyl group;

[0101] H in the compound of formula IB and the compound of formula IA can each independently be replaced by at least one of -F, -CN, -D (deuterium atom), C1-C6 alkyl, C1-C6 alkoxy, phenyl, biphenyl, naphthyl, phenanthryl, anthracenyl, fluorenyl, benzofluorenyl, dibenzofluorenyl, triphenylene, fluoranthenyl, pyrenyl, perylenyl, spirofluorenyl, indenofluorenyl or hydrogenated benzanthryl.

[0102] Preferably, Ar is a fluoranthenyl group, and m+n>1.

[0103] Preferably, H in the compound of formula IB and the compound of formula IA can be replaced by at least one of -F, -CN, -D, C1-C3 alkyl (for example, methyl, ethyl or propyl), C1-C3 alkoxy (for example, methoxy, ethoxy or propoxy), phenyl, biphenyl, triphenylene, and fluoranthene.

[0104] Preferably, L, Ar1, Ar2 are each independently selected from at least one of phenyl, biphenyl, naphthyl, phenanthryl, anthracenyl, fluorenyl, benzofluorenyl, dibenzofluorenyl, triphenylene, fluoranthenyl, pyrene, perylenyl, spirofluorenyl, indenofluorenyl or hydrogenated benzanthryl.

[0105] Preferably, the compound of formula IB is selected from any one of the following compounds 1-112:

[0106]

[0107] In the OLED device provided by the present invention, the hole layer material may include conventional hole materials in the art in addition to the compound described in formula HT-GH4, the compound of formula IB, and the compound of formula IA, without special restrictions. Exemplary includes but is not limited to: triarylamine compounds or carbazole compounds. Triarylamine compounds or carbazole compounds containing more than 3 N atoms are preferred, because the HOMO of triarylamine compounds or carbazole compounds containing more than 3 N atoms is higher (smaller absolute value), and is more suitable for use as hole injection layer materials. Triarylamine compounds or carbazole compounds containing 2 or 1 N atoms can be used as hole transport layer materials. Some compounds or carbazole compounds containing 1 N atom, if they have a higher LUMO, can also be used as electron blocking layer materials.

[0108] The triarylamine compound or the carbazole compound is used as the hole layer material, and the hole layer material includes the following structure:

[0109]

[0110] Among them, Ar 601 ~Ar 609 Each independently selected from a substituted or unsubstituted C6-C40 (for example, C6, C8, C10, C12, C16, C20, C24, C28, C30, C32, C36 or C40, etc.) aryl, a substituted or unsubstituted dibenzothienyl, a substituted or unsubstituted naphthobenzofuranyl, a substituted or unsubstituted naphthobenzothienyl, a substituted or unsubstituted dinaphthofuranyl, a substituted or unsubstituted dinaphthothienyl;

[0111] And Ar 601 ~Ar 609 Ar atoms adjacent to or connected to the same N atom 601 ~Ar 609 , can be connected by single key or through O, S, CR 701 R 702 NR 703 bridging;

[0112] R 701 , R 702 , R 703 is selected from C6-C40 (e.g., C6, C8, C10, C12, C16, C20, C24, C28, C30, C32, C36, or C40, etc.) aromatic groups, C6-C20 (e.g., C6, C8, C10, C12, C16, or C20, etc.) heteroaryl groups, C1-C6 (e.g., C1, C2, C3, C4, C5, or C6) alkyl groups, and R 701 , R 702Can connect via one-touch.

[0113] The hole blocking layer (HBL) can confine holes and / or excitons within the EL to improve the current efficiency and lifetime of the device. Compared with the EL material closest to the HBL interface, the HBL material has a lower HOMO (larger absolute value) and / or higher triplet energy.

[0114] The electron transport layer (ETL) may include a material capable of transporting electrons. The electron transport layer may be intrinsic (undoped) or doped, and doping may be used to enhance conductivity. In the present invention, there is no particular restriction on the ETL material, and any metal complex or organic compound may be used as long as it can transport electrons. The general electron transport layer material contains the following structural fragments: at least one of a pyridine structure, a pyrimidine structure, a triazine structure, a benzimidazole structure, a benzoxazole structure, a benzothiazole structure, an N-naphthalene structure, an N-coffee structure, an N-carbazole structure, and an N-dibenzothiophene structure.

[0115] In the present invention, there is no special restriction on the electron transport layer material, which exemplarily includes but is not limited to:

[0116]

[0117] In the present invention, the material of the cathode is a metal with a low work function (e.g., alkaline earth metal, alkali metal, main group metal or lanthanide element (e.g., Ca, Ba, Mg, Al, In, Mg, Yb, Sm, etc.)), a metal alloy composed of multiple metals (alloy composed of alkali metal or alkaline earth metal and silver, such as an alloy composed of magnesium and silver) or a multilayer structure. If the cathode material is a multilayer structure, in addition to the metals mentioned above, other metals with relatively high work functions, such as Ag or Al, can also be used. In this case, a combination of the metals is usually used, such as Ca / Ag, Mg / Ag or Ba / Ag.

[0118] It is also possible to introduce a thin intermediate layer of a material with a high dielectric constant between the metal cathode and the organic semiconductor to form a multilayer structure; the material with a high dielectric constant can also be called an electron injection material, and fluorides of alkali metals or alkaline earth metals, and corresponding oxides or carbonates (such as LiF, Li2O, BaF2, MgO, NaF, CsF, Cs2CO3, etc.) or lithium quinoline (LiQ) can be selected.

[0119] Compared with the prior art, the present invention has the following beneficial effects:

[0120] In the present invention, the structure of the carbazole compound is designed to make it suitable as the main material of the phosphorescent light-emitting layer of the organic electroluminescent device, so that the organic electroluminescent device has a lower driving voltage, a higher current efficiency and a longer life. DETAILED DESCRIPTION

[0121] For the convenience of understanding the present invention, the present invention lists the following embodiments. It should be understood by those skilled in the art that the embodiments are only to help understand the present invention and should not be regarded as specific limitations of the present invention.

[0122] Preparation Example 1

[0123] This preparation example provides an intermediate P1-1, the synthesis method of which is as follows:

[0124]

[0125] Under nitrogen protection, 30 mL of toluene, 10 mL of ethanol and 10 mL of water were added to a three-necked flask in sequence, and then 3.8 g of 2,3-dibromotriphenylene, 1.2 g of phenylboric acid, 2.12 g (0.02 mol) of sodium carbonate and 0.23 g (0.0002 mol) of tetrakistriphenylphosphine palladium were added thereto. The temperature was slowly raised to 60°C for reaction for 4 hours, then raised to 80°C for reaction for 2 hours, cooled to room temperature, and water was added to separate the mixture. The organic layer was washed with water, dried with magnesium sulfate, the desiccant was removed, and the mixture was concentrated to dryness and crystallized with ethanol to obtain 2.1 g of intermediate P1-1.

[0126] The obtained intermediate P1-1 was subjected to mass spectrometry detection, and the mass-to-charge ratio (m / z) was measured to be 382.04.

[0127] Preparation Example 2-6

[0128] Preparation Examples 2-6 respectively provide an intermediate. The synthesis method of the intermediate can refer to the synthesis method of intermediate P1-1 provided in Preparation 1. The corresponding raw materials are used to react to prepare the corresponding intermediates, as shown in Table 1 below.

[0129] The obtained intermediates were subjected to mass spectrometry detection, and the mass-to-charge ratio (m / z) data are shown in Table 1 below.

[0130] Table 1

[0131]

[0132]

[0133] Synthesis Example 1

[0134] This synthesis example provides compound P1 and its synthesis method, the synthesis method is as follows:

[0135]

[0136] Under a nitrogen atmosphere, dry toluene (120 mL), intermediate P1-1 (3.8 g), intermediate P1-2 (4.1 g), Pd(dba)2 (bis(dibenzylideneacetonepalladium, 0.1 g), 10% tri-tert-butylphosphine toluene solution (the mass of tri-tert-butylphosphine solution is 0.8 g) and sodium tert-butoxide (1.2 g) were added to a three-necked flask, and the reaction was heated to reflux for 8 h. The mixture was cooled to room temperature, and water was added to separate the mixture. The organic layer was then washed with water until it was neutral, dried over magnesium sulfate, filtered to remove the magnesium sulfate, and concentrated to dryness. The mixture was separated by silica gel column chromatography and eluted with petroleum ether:ethyl acetate = 10:0.5 (volume ratio) to obtain compound P1 (5.1 g).

[0137] The mass spectrometry detection of compound P1 was performed: the mass-to-charge ratio (m / z) was measured to be 710.27.

[0138] Synthesis Example 2-8

[0139] Synthesis Examples 2-8 respectively provide a compound, the specific structure of the compound is shown in Table 2, the compound is synthesized by referring to the synthesis method in Synthesis Example 1, and the obtained compound is subjected to mass spectrometry detection, and the mass-to-charge ratio (m / z) is measured and shown in Table 2 below.

[0140] Table 2

[0141]

[0142]

[0143]

[0144]

[0145] Other compounds whose specific synthesis methods are not listed can be synthesized by referring to the above embodiments in combination with common knowledge in the art.

[0146] The specific structures of some compounds used in the following application examples and comparative application examples of the present invention are as follows:

[0147]

[0148]

[0149] Application Example 1

[0150] This application example provides a green light organic electroluminescent device, using the compound provided by the present invention as a main material of the light-emitting layer, and the structure of the green light organic electroluminescent device is:

[0151] ITO / HT-1: HI-2[5%](80nm) / HT-1(30nm) / EB-1(20nm) / host material: PGD-1[5%](35nm) / ETL-1(25nm) / LiF(0.5nm) / Al(150nm).

[0152] The preparation method of the green organic electroluminescent device is as follows:

[0153] The material was placed in a vacuum chamber and evacuated to 1×10 -5 ~1×10 -6 Pa was vacuum evaporated onto the cleaned ITO substrate in sequence to prepare an OLED device.

[0154] PGD-1[5%] refers to the doping ratio of the dye, that is, the volume ratio of the main material to the dye PGD-1 is 95:5; HT-1:HI-2[5%] refers to the ratio of the P-type dopant, that is, the volume ratio of the hole material HT-1 and the P-type dopant HI-2 is 95:5. HT-1 is a hole transport material; HT-1:HI-2[5%] is used as a hole injection layer, and EB-1 is an electron blocking layer.

[0155] The main material of the light-emitting layer of the green organic electroluminescent device provided in this application example is compound P1.

[0156] Application Example 2-15, Comparative Application Example 1-3

[0157] Application Examples 2-15 and Comparative Application Examples 1-3 respectively provide a green light organic electroluminescent device, which differs from Application Example 1 only in that the main material of the light-emitting layer is replaced with other compounds (see Table 3 below for details), and the other preparation steps and conditions are the same as those of Application Example 1.

[0158] Performance Testing

[0159] The brightness, voltage, current efficiency and LT95 of the organic electroluminescent device provided above were tested, wherein the voltage and current efficiency were the brightness of 1000 cd / m 2 The corresponding value, LT95, refers to maintaining the initial current density of the device at 10mA / cm 2 The time required for the device efficiency to drop to 95% of the efficiency corresponding to the initial current density is constant. The voltage, current efficiency and LT95 are relative values. The specific test results are shown in Table 3 below:

[0160] Table 3

[0161] Main material <![CDATA[Luminance / (cd / m 2 )]]> Voltage Current efficiency LT95 Application Example 1 P1 1000 0.96 1.20 1.18 Application Example 2 P2 1000 0.95 1.16 1.12 Application Example 3 P3 1000 0.95 1.15 1.23 Application Example 4 P4 1000 0.80 1.18 1.02 Application Example 5 P5 1000 0.92 1.31 1.17 Application Example 6 P6 1000 0.82 1.02 1.13 Application Example 7 P7 1000 0.92 1.21 1.16 Application Example 8 P8 1000 0.97 1.17 1.19 Application Example 9 P9 1000 0.89 1.18 1.32 Application Example 10 P10 1000 0.89 1.02 1.01 Application Example 11 P11 1000 0.99 1.21 1.28 Application Example 12 P12 1000 0.97 1.36 1.12 Comparative application example 1 D1 1000 1 1 1

[0162] From the above content, it can be seen that the present invention designs the structure of the carbazole compound to make it suitable as the main material of the phosphorescent light-emitting layer of the organic electroluminescent device, so that the organic electroluminescent device has a lower driving voltage, higher current efficiency and longer life.

[0163] From the comparison between Application Example 1 and Application Example 11, it can be seen that the organic electroluminescent device prepared by using the carbazole compound having the structure shown in Formula I-2 as the main material of the light-emitting layer of the organic electroluminescent device has a better lifespan.

[0164] From the comparison between Application Example 1 and Application Example 12, it can be seen that the organic electroluminescent device prepared by using the carbazole compound having the structure shown in Formula I-3 as the main material of the light-emitting layer of the organic electroluminescent device has a better current efficiency.

[0165] In summary, the structure of the carbazole compound is designed in the present invention to make it suitable as the main material of the phosphorescent light-emitting layer of the organic electroluminescent device, so that the organic electroluminescent device has a lower driving voltage, higher current efficiency and longer life.

[0166] The applicant declares that the present invention illustrates the detailed process flow of the present invention through the above-mentioned embodiments, but the present invention is not limited to the above-mentioned detailed process flow, that is, it does not mean that the present invention must rely on the above-mentioned detailed process flow to be implemented. Those skilled in the art should understand that any improvement of the present invention, equivalent replacement of various raw materials of the product of the present invention, addition of auxiliary components, selection of specific methods, etc., all fall within the protection scope and disclosure scope of the present invention.

Claims

1. A carbazole compound, characterized in that: The carbazole compound has a structure shown in the following formula I: Ar1 and Ar2 are each independently selected from any one of a C6-C40 aryl group or a C6-C30 heteroaryl group; The hydrogen atoms in the compound of formula I may each independently be substituted by at least one of a deuterium atom, -F, -CN, a C6-C20 aryl group, a triphenylmethyl group, a triphenylsilyl group, a C1-C12 alkyl group or a C1-C12 alkoxy group.

2. The carbazole compound according to claim 1, characterized in that The carbazole compound has any one of the structures shown in the following formula I-1, formula I-2 or formula I-3: Wherein, Ar1 and Ar2 in the compound of formula I-1, the compound of formula I-2 or the compound of formula I-3 are each independently selected from any one of C6-C40 aryl or C6-C30 heteroaryl; The hydrogen atoms in the compound of formula I-1, the compound of formula I-2 or the compound of formula I-3 may each independently be substituted by at least one of a deuterium atom, -F, -CN, a C6-C20 aryl group, a triphenylmethyl group, a triphenylsilyl group, a C1-C12 alkyl group or a C1-C12 alkoxy group.

3. The carbazole compound according to claim 1 or 2, characterized in that The C6-C40 aryl group is selected from any one or a combination of at least two of phenyl, biphenyl, terphenyl, naphthyl, anthracenyl, phenanthrenyl, fluorenyl, benzofluorenyl, dibenzofluorenyl, naphthfluoroenyl, pyrenyl, peryl, spirofluorenyl, triphenylene, fluoranthenyl, hydrogenated benzanthryl, indenofluorenyl, benzoindenofluorenyl, dibenzoindenofluorenyl, naphthfluoroenyl, tetraphenylmethane or benzonaphthfluoroenyl; Preferably, the C6-C30 heteroaryl group is selected from any one or a combination of at least two of carbazolyl, dibenzothiophenyl, dibenzofuranyl, naphthobenzofuranyl, naphthobenzothiophenyl, dinaphthofuranyl and dinaphthothiophenyl; Preferably, the C6-C20 aryl group is selected from any one of phenyl, naphthyl, biphenyl, anthracenyl, phenanthryl, fluorenyl, triphenylene or fluoranthenyl; Preferably, the C1-C12 alkyl group is selected from any one of methyl, ethyl, propyl, n-butyl, tert-butyl, cyclopentyl, cyclohexyl, octyl and adamantyl; Preferably, the C1-C12 alkoxy group is selected from any one of methoxy, ethoxy, propoxy, butoxy, pentyloxy, hexyloxy and octyloxy.

4. The carbazole compound according to any one of claims 1 to 3, characterized in that Ar1 and Ar2 are each independently selected from any one or a combination of at least two of phenyl, carbazolyl, biphenyl, 9,9-dimethylfluorenyl, naphthyl, triphenylene, fluoranthenyl, indenofluorenyl, dibenzofuranyl, dibenzothienyl, naphthobenzofuranyl or naphthobenzothienyl; Preferably, Ar1 and Ar2 are each independently selected from at least one of phenyl, carbazolyl, naphthyl, 9,9-dimethylfluorenyl, dibenzothiophenyl, biphenyl, dibenzofuranyl, triphenylene or fluoranthene; Preferably, Ar1 and Ar2 are each independently selected from at least one of phenyl, naphthyl, biphenyl, dibenzofuranyl, dibenzothiophenyl and carbazole.

5. The carbazole compound according to any one of claims 1 to 4, characterized in that The hydrogen atoms in the compound of formula I may be independently substituted by at least one of -D, -F, -CN, phenyl, naphthyl, biphenyl, triphenylmethyl, triphenylsilyl, methyl, ethyl, propyl, butyl, methoxy, ethoxy, propoxy or butoxy; Preferably, the hydrogen atoms in the compound of formula I can be independently substituted by at least one of -D, -F, -CN, phenyl, naphthyl, methyl, ethyl, tert-butyl, methoxy, ethoxy and propoxy.

6. The carbazole compound according to any one of claims 1 to 5, characterized in that: The carbazole compound is selected from any one of the following substituted or unsubstituted compounds: The substitution means that the hydrogen atoms in the above carbazole compounds can be independently replaced by deuterium atoms; preferably, the carbazole compounds are selected from any one of the following compounds:

7. An intermediate, characterized in that The intermediate includes a compound having a structure shown in the following formula MA: Wherein, Ar2 has the same definition as in claim 1; X1 is selected from any one of -F, -Cl, -Br or -I; The hydrogen atoms in the compound of formula MA may each independently be substituted by at least one of -D, -CN, -F, C6-C20 aryl, C6-C30 heteroaryl, C1-C12 alkyl or C1-C12 alkoxy.

8. The intermediate according to claim 7, characterized in that The intermediates include the following compounds:

9. An organic electroluminescent device, characterized in that: The organic electroluminescent device comprises an anode, a cathode and an organic thin film layer arranged between the anode and the cathode; The organic thin film layer material comprises the carbazole compound according to any one of claims 1 to 6.

10. The organic electroluminescent device according to claim 9, characterized in that: The organic thin film layer comprises a light-emitting layer, and a main material of the light-emitting layer comprises the carbazole compound according to any one of claims 1 to 6.

Images