A carbazole compound, intermediate, composition and organic electroluminescent device

Abstract

This invention provides a carbazole compound, an intermediate, a composition, and an organic electroluminescent device. The carbazole compound has the structure of Formula I. This invention designs the structure of the carbazole compound to make it suitable as the main material for the light-emitting layer of an organic electroluminescent device, resulting in an organic electroluminescent device with lower driving voltage, higher current efficiency, and longer lifetime.

Description

Technical Field

[0001] This invention belongs to the field of organic electroluminescent materials technology, specifically relating to a carbazole compound, intermediate, composition, and organic electroluminescent device. Background Technology

[0002] The structure of an organic light-emitting diode (OLED) device specifically consists of an anode, a cathode, and an organic layer between them. To improve the efficiency and stability of OLED devices, the organic material layer comprises multiple layers with different materials, such as a hole injection layer (HIL), a hole transport layer (HTL), a hole blocking layer, an emissive layer, an electron transport layer (ETL), and an electron injection layer (EIL). Currently, organic light emission has become a mainstream display technology, and correspondingly, various novel OLED materials have been developed.

[0003] To meet the higher demands of people for OLED devices, there is an urgent need in the field to develop more types of materials to improve the performance of OLED devices in terms of current efficiency, lifetime, and other aspects. Summary of the Invention

[0004] To address the shortcomings of existing technologies, the present invention aims to provide a carbazole compound, intermediate, composition, and organic electroluminescent device. In this invention, the structure of the carbazole compound is designed to be suitable as the main material for the phosphorescent layer of an organic electroluminescent device, resulting in an organic electroluminescent device with lower driving voltage, higher current efficiency, and longer lifespan.

[0005] To achieve this objective, the present invention adopts the following technical solution:

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

[0007]

[0008] Ar1, Ar2, and Ar3 are each independently selected from any one of C6-C40 aryl or C6-C30 heteroaryl.

[0009] A1, A2, and A3 are each independently selected from N or CR, and at least one is selected from N; R is selected from any one of H, -CN, C6-C20 aryl or C1-C12 alkyl;

[0010] In the compound of formula I, each hydrogen atom can be independently replaced by a deuterium atom.

[0011] In this invention, the structure of carbazole compounds is designed to be suitable as the main material for the phosphorescent light-emitting layer of organic electroluminescent devices, thereby enabling the organic electroluminescent devices to have lower driving voltage, higher current efficiency, and longer lifespan.

[0012] In this invention, C6-C40 can be C6, C8, C10, C12, C16, C20, C24, C28, C30, C32, C36 or C40, etc.

[0013] C6-C30 can be C6, C8, C10, C12, C16, C20, C24, C28, or C30, etc.

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

[0015] C1-C12 can be C1, C2, C3, C4, C5, C6, C7, C8, C9, C10, C11 or C12.

[0016] It should be noted that in this invention, "D" represents a deuterium atom, and the same applies below.

[0017] The following are preferred technical solutions of the present invention, but are not intended to limit the technical solutions provided by the present invention. The purpose and beneficial effects of the present invention can be better achieved and realized through the following preferred technical solutions.

[0018] As a preferred embodiment of the present invention, the compound of formula I includes a compound having the structure shown in formula I-1 as follows:

[0019]

[0020] Ar1, Ar2, Ar3, A1, A2, and A3 have the same definitions as above.

[0021] As a preferred embodiment of the present invention, the C6-C40 aryl group is selected from any one or a combination of at least two of the following: phenyl, biphenyl, terphenyl, naphthyl, anthracene, phenanthrene, fluorenyl, benzo[a]fluorenyl, dibenzo[a]fluorenyl, naphthyl, pyrene, perylene, spirofluorenyl, triphenylene, fluoranyl, hydrogenated benzo[a]anthrayl, ind[a]fluorenyl, benzo[a]ind[a]fluorenyl, dibenzo[a]ind[a]fluorenyl, naphthyl, tetraphenylmethane, or benzo[a]naphthyl.

[0022] As a preferred embodiment of the present invention, the C6-C30 heteroaryl group is selected from any one or a combination of at least two of carbazolyl, dibenzothiophenel, dibenzofuranyl, naphthobenzofuranyl, naphthobenzothiophenel, dinaphthofuranyl, and dinaphthothiophenel.

[0023] Preferably, the C6-C20 aryl group is selected from any one of phenyl, naphthyl, biphenyl, anthracene, phenanthryl, fluorenyl, triphenylene, or fluoranthracene.

[0024] Preferably, the C1-C12 alkyl group is selected from any one of methyl, ethyl, propyl, n-butyl, tert-butyl, cyclopentyl, cyclohexyl, octyl, and adamantyl.

[0025] As a preferred embodiment of the present invention, Ar1, Ar2, and Ar3 are each independently selected from at least one of phenyl, carbazolyl, naphthyl, 9,9-dimethylfluorenyl, dibenzothiophene, biphenyl, dibenzofuranyl, triphenylene, or fluoranyl.

[0026] Preferably, Ar1 is selected from any one of phenyl, naphthyl, biphenyl, dibenzofuranyl, dibenzothiophenyl or carbazoleyl.

[0027] Preferably, Ar2 and Ar3 are each independently selected from phenyl, biphenyl, naphthyl, and carbazole groups. Dashed lines indicate connection sites (the same applies below), dibenzofuranyl, phenyl-substituted carbazole group Any one or at least two of them.

[0028] Preferably, Ar1, Ar2, and Ar3 are each independently selected from any one of phenyl, biphenyl, or naphthyl.

[0029] Preferably, Ar1, Ar2, and Ar3 are all selected from phenyl groups.

[0030] Preferably, Ar1 is dibenzofuranyl.

[0031] Preferably, Ar1 is carbazole-based.

[0032] Preferably, any one of A1, A2, and A3 is selected from N, the other two are selected from CR, and R is selected from H.

[0033] Preferably, any two of A1, A2, and A3 are selected from N, the other is selected from CR, and R is selected from H.

[0034] Preferably, A1, A2, and A3 are all selected from N.

[0035] As a preferred embodiment of the present invention, the carbazole compound is selected from any one of the following substituted or unsubstituted compounds:

[0036]

[0037]

[0038] The substitution refers to the independent replacement of each hydrogen atom in the aforementioned carbazole compounds by a deuterium atom.

[0039] Preferably, the carbazole compound is selected from any one of the following compounds:

[0040]

[0041] It should be noted that the present invention does not impose any special limitations on the preparation method of the above-mentioned carbazole compounds, and commonly used preparation methods in the art are applicable.

[0042] In a second aspect, the present invention provides an intermediate comprising the following compounds:

[0043]

[0044] The intermediate is used to prepare carbazole compounds as described in the first aspect.

[0045] Thirdly, the present invention provides a composition comprising a first component and a second component;

[0046] The first component includes carbazole compounds as described in the first aspect;

[0047] The second component includes compound A;

[0048] Compound A is obtained by fusion of a group with the structure shown in Formula IA and any two adjacent carbon atoms on ring A in the group with the structure shown in Formula IB:

[0049]

[0050] Where * represents a fusion site;

[0051] X is selected from O, S, R 301 R 302 Each is independently selected from C1-C6 alkyl, C6-C30 aryl, or C6-C20 heteroaryl, and R 301 R 302 A ring can be formed by connecting with a single key, R 303 Selected from C6-C30 aryl or C6-C20 heteroaryl, with dashed lines indicating connection sites;

[0052] Ar 22 Selected from C6-C30 aryl or C6-C20 heteroaryl;

[0053] In compound A, each hydrogen atom can be independently substituted by at least one of -F, -CN, C6-C20 aryl, C1-C6 alkyl, and C1-C6 alkoxy.

[0054] In compound A, C6-C30 can be C6, C10, C12, C18, C24, or C30, etc.

[0055] The C6-C20 can be C6, C10, C12, C18, or C20, etc.

[0056] The C1-C6 can be C1, C2, C3, C4, C5 or C6.

[0057] As a preferred technical solution of the present invention, the R 303 Ar 22 Each group is independently selected from any one or a combination of at least two of the following substituted or unsubstituted groups: phenyl, biphenyl, naphthyl, anthracene, phenanthrene, fluorenyl, benzo[a]fluorenyl, dibenzo[a]fluorenyl, triphenylene, fluoranyl, pyrene, perylene, spirofluorenyl, dibenzofuranyl, dibenzothiophene, naphthobenzofuran, naphthobenzothiophene, dinaphthofuran, dinaphthothiophene, hydrogenated benzene Anthrayl, indo-carbazolyl, indo-carbazolyl, terphenyl, tetraphenyl, imidazolyl, benzimidazolyl, pyridyl, pyrimidinyl, piperazine, quinolinyl, isoquinolinyl, quinoxalinyl, quinazolinyl, benzoquinoxalinyl, benzoquinoxalinyl, N-phenanthroline, diazanthroline, carbazolyl, benzo-carbazolyl, naphtho-carbazolyl, dibenzo-carbazolyl, triazine;

[0058] The substituents are each independently selected from at least one of C1-C12 (e.g., C1, C2, C5, C6, C8, C10, or C12), C1-C12 (e.g., C1, C2, C5, C6, C8, C10, or C12), and C6-C12 (e.g., C6, C7, C8, C9, C10, C11, or C12) aryl groups.

[0059] As a preferred technical solution of the present invention, the R 303 Ar 22 Each group is independently selected from any one or a combination of at least two of the following substituted or unsubstituted groups: phenyl, biphenyl, naphthyl, phenanthryl, anthracene, 9,9-dimethylfluorenyl, 9,9-diphenylfluorenyl, spirofluorenyl, dibenzofuranyl, dibenzothiopheneyl, triphenylene, fluorenyl, benzofluorenyl, carbazoleyl;

[0060] The substituent is selected from at least one of methyl, ethyl, tert-butyl, adamantyl, cyclohexyl, cyclopentyl, 1-methylcyclopentyl, 1-methylcyclohexyl, methoxy, phenyl, biphenyl, 9,9-dimethylfluorenyl, dibenzofuranyl, dibenzothiophene, or naphthyl.

[0061] Preferably, X is selected from O and S.

[0062] Preferably, the R 301 R 302 Each is independently selected from methyl or phenyl.

[0063] Preferably, the R 303 It is selected from any one of phenyl, diphenyl, or triphenyl.

[0064] Preferably, the Ar 22 It is selected from any one of biphenyl, terphenyl, or tetraphenyl.

[0065] Preferably, the R 303 The Ar is phenyl. 22 It is selected from any one of biphenyl, terphenyl, or tetraphenyl.

[0066] Preferably, the R 303 It is a diphenyl group, and the Ar is... 22 Selected from diphenyl or triphenyl.

[0067] As a preferred embodiment of the present invention, compound A has a structure as shown in any one of formulas I-1 to I-30:

[0068]

[0069]

[0070] Among them, R 303 Ar 22 It has the same definition as above;

[0071] Each of the compounds of formulas I-1 to I-30 may be independently substituted by at least one of -F, -CN, C6-C20 (e.g., C6, C10, C12, C18 or C20), C1-C6 (e.g., C1, C2, C3, C4, C5 or C6) alkyl, or C1-C6 (e.g., C1, C2, C3, C4, C5 or C6) alkoxy.

[0072] As a preferred embodiment of the present invention, compound A is selected from any one of the following compounds:

[0073]

[0074]

[0075]

[0076]

[0077]

[0078]

[0079]

[0080]

[0081]

[0082]

[0083]

[0084]

[0085]

[0086]

[0087]

[0088] Preferably, compound A is selected from any one of the following compounds:

[0089]

[0090]

[0091]

[0092]

[0093] It should be noted that there are no special restrictions on the preparation method of the above-mentioned compound A in this invention, and commonly used preparation methods in the art are applicable.

[0094] Fourthly, 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;

[0095] The organic thin film layer material includes carbazole compounds as described in the first aspect and / or compositions as described in the third aspect.

[0096] As a preferred embodiment of the present invention, the organic thin film layer includes a light-emitting layer, and the main material of the light-emitting layer includes carbazole compounds as described in the first aspect and / or compositions as described in the third aspect.

[0097] Preferably, the light-emitting layer is a phosphorescent light-emitting layer.

[0098] As a preferred embodiment of the present invention, the organic electroluminescent device is a green organic electroluminescent device.

[0099] In this invention, the light-emitting layer comprises a host material and a dopant material, wherein the dopant material is also called a dye or a phosphorescent material. The host material of the light-emitting layer can be a single compound or a mixture of two or more compounds.

[0100] The light-emitting layer includes a phosphorescent light-emitting layer, which 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.

[0101] The volume percentage of the main material in the phosphorescent luminescent layer is 60% to 99.9% (e.g., it can be 60%, 65%, 70%, 75%, 80%, 85%, 90%, 95%, 98%, or 99.9%), preferably 70% to 99.5%, and more preferably 85% to 95%.

[0102] In this invention, the doping material of the light-emitting layer can be a phosphorescent material, also known as a triplet luminescent material, which refers to the light emitted by a substance from a triplet excited state. The specific selection of phosphorescent materials in this invention is not particularly limited; commonly used doping materials for the light-emitting layer in this field are applicable, including but not limited to compounds having the structure shown in the formula PD.

[0103]

[0104] Wherein, M is selected from any one of Ir, Pt, Pd, Os, Ti, Zr, Hf, Eu, Tb, Tm, Cu or Au;

[0105] Y1-Y4 are each independently selected from carbon or nitrogen;

[0106] Y1 and Y2 can be connected by a single key or a double key, and Y3 and Y4 can be connected by a single key or a double key.

[0107] Cy1 and Cy2 are each independently selected from any one of phenyl, naphthyl, fluorenyl, spirofluorenyl, indyl, pyrroleyl, thiopheneyl, furanyl, imidazolyl, pyrazolyl, thiazolyl, isothiazolyl, pyridinyl, pyrazinyl, pyrimidinyl, pyridazinyl, quinolinyl, isoquinolinyl, benzoquinolinyl, quinoxalinyl, quinazolinyl, carbazoleyl, benzimidazolyl, benzofuranyl, benzothiopheneyl, isobenzothiopheneyl, benzimidazolyl, benzozolyl, triazolyl, tetrazolyl, diazolyl, triazinyl, dibenzothiopheneyl, and n-hexacarbazolyl, wherein Cy1 and Cy2 may optionally be linked to each other via a single bond or an organic linking group;

[0108] Any two or more ligands of M can be connected by single or double bonds, or by O or S bridging, or by any chemical group or chemical structure to form a structure that conforms to chemical principles.

[0109] R 91 and R 92 Each group is independently selected from -H, -D, -F, -Cl, -Br, -I, hydroxyl, cyano, nitro, amino, amidine, hydrazine, hydrazone, carboxylic acid group, carboxylate group, sulfonic acid group, sulfonate group, phosphate group, phosphate group, -SF5, substituted or unsubstituted C1-C60 (e.g., can be C1, C5, C10, C15, C20, C25, C30, C35, C40, C45, C50, C55, or C60, etc.) alkyl, substituted or unsubstituted C2-C6. 0 (e.g., can be C2, C5, C10, C15, C20, C25, C30, C35, C40, C45, C50, C55, or C60, etc.) alkenyl, substituted or unsubstituted C2-C60 (e.g., can be C2, C5, C10, C15, C20, C25, C30, C35, C40, C45, C50, C55, or C60, etc.) alkynyl, substituted or unsubstituted C1-C60 (e.g., can be C1, C5, C10, C15, C20, C40, C50, C55, C60, etc.) alkyne, substituted or unsubstituted C1-C60 (e.g., can be C1, C5, C10, C15, C20, C50, C10, C15, C20, C1 ... 25. alkoxy, substituted or unsubstituted C2-C10 (e.g., C2, C3, C4, C5, C6, C7, C8, C9, or C10), heterocyclic alkyl, substituted or unsubstituted C6-C60 (e.g., C6, C12, C15, C18, C24, C30, C32, C36, C40, C42, C54, or C60), aryl, substituted or unsubstituted C6-C60 (… For example, it can be any one of the following: aryloxy group (C6, C12, C15, C18, C24, C30, C32, C36, C40, C42, C54 or C60, etc.), substituted or unsubstituted C6-C60 (e.g., it can be C6, C12, C15, C18, C24, C30, C32, C36, C40, C42, C54 or C60, etc.), substituted or unsubstituted monovalent non-aromatic fused polycyclic group, or substituted or unsubstituted monovalent non-aromatic fused heterocyclic group.

[0110] a1 and a2 are each independent integers selected from 1 to 5, for example, they can be 1, 2, 3, 4 or 5;

[0111] b is an integer selected from 0 to 4, for example, it can be 0, 1, 2, 3 or 4;

[0112] a is selected from 1, 2, or 3;

[0113] L1 can be a monovalent organic ligand, a divalent organic ligand, or a trivalent organic ligand.

[0114] Preferably, the PD compound is selected from any one of the following compounds:

[0115]

[0116]

[0117]

[0118]

[0119]

[0120]

[0121] In this invention, the organic thin film layer includes a hole layer, which comprises a hole injection layer, a hole transport layer, and an electron blocking layer.

[0122] The hole injection layer material includes a P-type dopant. A P-type dopant is a material that coexists with the hole injection layer material in the OLED device, oxidizing the hole injection layer material and thus acting as an electron acceptor to promote the movement of holes from the hole injection layer to the anode. In this 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.

[0123] The p-type dopant exists in the hole injection layer at a volume percentage of 1% to 10% (e.g., 1%, 2%, 4%, 6%, 8%, or 10%). In this invention, no particular limitation is made on the type of p-type dopant; compounds HI-1 to HI-9 as described below can be used exemplary.

[0124]

[0125] In this invention, the hole layer material (including a hole injection layer, a hole transport layer, and an electron blocking layer) has the structure shown in the following formula HT-GH4:

[0126]

[0127] Among them, L 41 Selected from single-bonded, C6-C40 (e.g., C6, C8, C10, C12, C16, C20, C24, C28, C30, C32, C36, or C40, etc.) aryl, and C6-C20 (e.g., C6, C8, C10, C12, C16, or C20, etc.) heteroaryl;

[0128] Ar 41 Ar 42Each is independently selected from C6-C40 (e.g., C6, C8, C10, C12, C16, C20, C24, C28, C30, C32, C36, or C40, etc.) aryl and C6-C20 (e.g., C6, C8, C10, C12, C16, or C20, etc.) heteroaryl;

[0129] X is selected from CR 41 R 42 Or NR 43 , where R 41 R 42 R 43 Each is independently selected from substituted or unsubstituted phenyl groups (the substituents are selected from C1-C6 (e.g., C1, C2, C3, C4, C5, or C6) alkyl, C1-C6 (e.g., C1, C2, C3, C4, C5, or C6) alkoxy, naphthyl, triphenylene, fluoranyl, 9,9-dimethylfluorenyl, biphenyl, substituted or unsubstituted group (the substituent is phenyl), substituted or unsubstituted dibenzothiophene (the substituent is phenyl), substituted thiophene, C1-C6 (e.g., C1, C2, C3, C4, C5, or C6) alkyl groups, R 41 R 42 They can be linked into rings via single bonds. Compounds of formula HT-GH4 are selected from any one of the following compounds:

[0130]

[0131]

[0132] In this invention, the hole layer material (including a hole injection layer, a hole transport layer, and an electron blocking layer) further includes a compound having a structure as shown in Formula IA or a compound having a structure as shown in Formula IB:

[0133]

[0134] Wherein, L is selected from any one of C6-C40 (e.g., it can be C6, C8, C10, C12, C16, C20, C24, C28, C30, C32, C36 or C40, etc.) arylene, dibenzofuranyl or dibenzothiophene group;

[0135] 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;

[0136] Ar is selected from any one of triphenylene, fluorene anthracene, dibenzofuranyl, or dibenzothiophene;

[0137] Ar1 and Ar2 are each independently selected from any one of aryl, dibenzofuran, or dibenzothiophene groups containing C6-C40 (e.g., C6, C8, C10, C12, C16, C20, C24, C28, C30, C32, C36, or C40, etc.);

[0138] Ar1 and Ar, Ar2 and Ar, and Ar1 and Ar2 can be independently connected or bridged by single bonds, O, S, CR1R2, NR.

[0139] R, R1, and R2 are each independently selected from any one of the following: C1-C20 (e.g., C1, C2, C4, C6, C8, C10, C12, C14, C16, C18, or C20), alkyl, C6-C40 (e.g., C6, C8, C10, C12, C16, C20, C24, C28, C30, C32, C36, or C40), aryl, dibenzofuranyl, or dibenzothiopheneyl.

[0140] In compounds of formula IB and formula IA, the H can be independently replaced by at least one of -F, -CN, -D (deuterium atom), C1-C6 alkyl, C1-C6 alkoxy, phenyl, biphenyl, naphthyl, phenanthryl, anthracene, fluorenyl, benzo[a]fluorenyl, dibenzo[a]fluorenyl, triphenylene, fluoranyl, pyrene, perylene, spirofluorenyl, indo[a]fluorenyl, or hydrogenated benzo[a]anthryl.

[0141] Preferably, the Ar is fluoreneanthracene, where m+n>1.

[0142] Preferably, the H in the compounds of formula IB and formula IA can be replaced by at least one of -F, -CN, -D, C1-C3 alkyl (e.g., methyl, ethyl, or propyl), C1-C3 alkoxy (e.g., methoxy, ethoxy, or propoxy), phenyl, biphenyl, triphenylene, and fluoranthyl.

[0143] Preferably, L, Ar1, and Ar2 are each independently selected from at least one of phenyl, biphenyl, naphthyl, phenanthryl, anthracene, fluorenyl, benzo[a]fluorenyl, dibenzo[a]fluorenyl, triphenylene, fluoranyl, pyrene, perylene, spirofluorenyl, indo[a]fluorenyl, or hydrogenated benzo[a]anthryl.

[0144] Preferably, the compound of formula IB is selected from any one of compounds 1-40:

[0145]

[0146]

[0147] In the OLED device provided by this invention, the hole layer material, in addition to the compounds described in formula HT-GH4, formula IB, and formula IA, may also include conventional hole materials in the art, without particular limitation. Exemplarily, it includes, but is not limited to, triarylamine compounds or carbazole compounds. Preferably, triarylamine compounds or carbazole compounds containing three or more nitrogen atoms are preferred because they have a higher HOMO (lower absolute value) and are more suitable as hole injection layer materials. Triarylamine compounds or carbazole compounds containing two or one nitrogen atom can be used as hole transport layer materials. Some compounds or carbazole compounds containing one nitrogen atom, if they have a high LUMO, can also be used as electron blocking layer materials.

[0148] The triaryl amine compound or carbazole compound is used as the hole layer material, and the hole layer material includes the following structure:

[0149]

[0150] Among them, Ar 601 ~Ar 609 Each is independently selected from any one of the following: substituted or unsubstituted C6-C40 (e.g., C6, C8, C10, C12, C16, C20, C24, C28, C30, C32, C36, or C40, etc.) aryl, substituted or unsubstituted dibenzothiophene, substituted or unsubstituted naphthobenzofuran, substituted or unsubstituted naphthobenzothiophene, substituted or unsubstituted dinaphthofuran, substituted or unsubstituted dinaphthothiophene;

[0151] And Ar 601 ~Ar 609 Ar atoms that are adjacent to or connected to the same N atom 601 ~Ar 609 It can be connected via a single key or via O, S, CR 701 R 702 NR 703 bridging;

[0152] R 701 R 702 R 703 Selected from C6-C40 (e.g., C6, C8, C10, C12, C16, C20, C24, C28, C30, C32, C36, or C40, etc.) aryl, C6-C20 (e.g., C6, C8, C10, C12, C16, or C20, etc.) heteroaryl, C1-C6 (e.g., C1, C2, C3, C4, C5, or C6) alkyl, and R 701 R 702It can be connected with a single button.

[0153] Hole blocking layers (HBLs) can confine holes and / or excitons within the emissive layer to improve device current efficiency and lifetime. Compared to emissive layer materials closest to the HBL interface, HBL materials exhibit lower HOMO (larger absolute values) and / or higher triplet energies.

[0154] An electron transport layer (ETL) may comprise a material capable of transporting electrons. The ETL may be intrinsic (undoped) or doped, and doping can be used to enhance conductivity. In this invention, there are no particular limitations on the ETL material; any metal complex or organic compound can be used, as long as it can transport electrons. Generally, electron transport layer materials contain at least one of the following structural segments: pyridine, pyrimidine, triazine, benzimidazole, benzoxazole, benzothiazole, N-naphthalene, N-phenanthion, N-carbazole, and N-dibenzothiophene.

[0155] In this invention, no special restrictions are placed on the electron transport layer material, which includes, but is not limited to, the following:

[0156]

[0157]

[0158] In this invention, the cathode material is a metal with low work function (e.g., alkaline earth metals, alkali metals, main group metals, or lanthanides (e.g., Ca, Ba, Mg, Al, In, Mg, Yb, Sm, etc.)), a metal alloy composed of multiple metals (an alloy composed of alkali metals or alkaline earth metals 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 function can also be used, such as Ag or Al. In this case, combinations of the metals are typically used, such as Ca / Ag, Mg / Ag, or Ba / Ag.

[0159] Alternatively, a thin interlayer of material with a high dielectric constant can be introduced 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 can be an alkali metal or alkaline earth metal fluoride, as well as the corresponding oxide or carbonate (e.g., LiF, Li2O, BaF2, MgO, NaF, CsF, Cs2CO3, etc.) or lithium quinoline (LiQ).

[0160] Compared with the prior art, the present invention has the following beneficial effects:

[0161] In this invention, the structure of carbazole compounds is designed to be suitable as the main material for the phosphorescent light-emitting layer of organic electroluminescent devices, thereby enabling the organic electroluminescent devices to have lower driving voltage, higher current efficiency, and longer lifespan. Detailed Implementation

[0162] To facilitate understanding of the present invention, the following embodiments are provided. Those skilled in the art should understand that these embodiments are merely illustrative and should not be construed as limiting the scope of the invention.

[0163] Synthesis of intermediate P1-1 in Preparation Example 1

[0164] This preparation example provides intermediate P1-1 and its synthesis method, which is as follows:

[0165]

[0166] (1) Synthesis of intermediate P1-2

[0167] Under nitrogen protection, 3.2 g of compound M1, 3.2 g of compound M0, 2.5 g of anhydrous potassium carbonate, 50 mL of o-dichlorobenzene, 10 mL of DMF, 0.1 g of cuprous oxide, and 0.2 g of o-phenanthroline were added to a three-necked flask. The mixture was first reacted at 80 °C for 4 hours, then heated to 120 °C and reacted for 8 hours. After cooling, the insoluble matter was removed by filtration, the mixture was washed with water, separated, and the organic layer was washed with water until neutral. The mixture was dried over anhydrous magnesium sulfate, and after filtering off the desiccant, it was concentrated to dryness. The mixture was crystallized in a mixed solvent of toluene and ethanol to obtain intermediate P1-2 (4.7 g).

[0168] The obtained intermediate P1-2 was analyzed by mass spectrometry, and the two largest m / z peaks were 509.04 (abundance 100%) and 507.04 (abundance 77%).

[0169] (2) Synthesis of intermediate P1-1

[0170] Under nitrogen protection, 80 mL of toluene, 40 mL of ethanol, and 20 mL of water were added sequentially to a three-necked flask. Then, 5.1 g of intermediate P1-2, 2.8 g of 4,6-diphenyl-1,3,5-triazine-2-boric acid, 2.12 g (0.02 mol) of sodium carbonate, and 0.23 g (0.0002 mol) of tetratetraphenylphosphine palladium were added. The mixture was slowly heated to reflux and reacted for 8 h. After cooling to room temperature, water was added to separate the organic layer. The organic layer was washed with water and dried with magnesium sulfate. After removing the desiccant, the mixture was concentrated to dryness and separated by silica gel column chromatography. The elution was performed with petroleum ether:dichloromethane:THF = 10:2:1 (volume ratio) to obtain intermediate P1-1 (5.6 g).

[0171] The obtained intermediate P1-1 was subjected to mass spectrometry, and the mass-to-charge ratio (m / z) was measured to be 660.21.

[0172] Synthesis of intermediate P2-1 in Preparation Example 2

[0173] This preparation example provides intermediate P2-1 and its synthesis method, which is as follows:

[0174]

[0175] (1) Synthesis of intermediate P2-2

[0176] Following the synthesis method of intermediate P1-2, intermediate P2-2 was prepared using the corresponding raw materials.

[0177] Mass spectrometry analysis of intermediate P2-2 revealed two peaks with the largest mass-to-charge ratio m / z: 585.07 (abundance 100%) and 583.07 (abundance 77%).

[0178] (2) Synthesis of intermediate P2-1

[0179] Following the synthesis method of intermediate P1-1, intermediate P2-1 was prepared using the corresponding raw materials.

[0180] Mass spectrometry analysis of intermediate P2-1 revealed a mass-to-charge ratio (m / z) of 736.24.

[0181] Synthesis of intermediate P7-1 in Preparation Example 3

[0182] This preparation example provides intermediate P7-1 and its synthesis method, which is as follows:

[0183]

[0184] Following the synthesis method of intermediate P1-1, intermediate P7-1 was prepared using the corresponding raw materials.

[0185] Mass spectrometry analysis of intermediate P7-1 revealed a mass-to-charge ratio (m / z) of 659.21.

[0186] Synthesis Example 1

[0187] This synthetic example provides compound P1 and its synthetic method, which is as follows:

[0188]

[0189] Under nitrogen protection, 100 mL of DMF, 6.6 g of intermediate P1-1, 1.3 g of phenylboronic acid, 2.12 g (0.02 mol) of sodium carbonate and 0.23 g (0.0002 mol) of tetrakis(triphenylphosphine)palladium were added sequentially to a three-necked flask. The mixture was slowly heated to reflux and reacted for 8 h. After cooling to room temperature, water and toluene were added and the mixture was separated. The organic layer was washed with water and dried with magnesium sulfate. After removing the desiccant, the mixture was concentrated to dryness and separated by silica gel column chromatography. The eluent was petroleum ether: dichloromethane: THF = 10:2:1 (volume ratio) to give compound P1 (5.9 g).

[0190] The obtained compound P1 was analyzed by mass spectrometry, and the mass-to-charge ratio (m / z) was found to be 702.28.

[0191] Synthesis Examples 2-6

[0192] Synthesis Examples 2-6 provide a compound, the specific structure of which is shown in Table 1 below. The compound is synthesized from raw material 1 and raw material 2. The synthesis method is the same as that of compound P1 in Synthesis Example 1. The obtained compound was subjected to mass spectrometry detection, and the mass-to-charge ratio (m / z) is shown in Table 1 below.

[0193] Table 1

[0194]

[0195]

[0196] Synthesis Example 7

[0197] This synthetic example provides compound P6 and its synthetic method, which is as follows:

[0198]

[0199] Under nitrogen protection, 60 mL of dry xylene, 6.6 g of intermediate P1-1, 1.7 g of carbazole, 0.0575 g of Pd(dba)2 (bis(dibenzylacetone)palladium), a 10% (w / w) solution of tri-tert-butylphosphine in toluene (0.4 g of tri-tert-butylphosphine solution and 0.0002 mol of tri-tert-butylphosphine) and 1.5 g of sodium tert-butoxide were added to a three-necked flask. The mixture was heated to reflux and reacted for 12 h. After cooling to room temperature, water was added to dissolve the mixture. The organic layer was then washed with water until neutral, dried with magnesium sulfate, filtered to remove magnesium sulfate, concentrated to dryness, and separated by silica gel column chromatography. The mixture was eluted with a solvent of petroleum ether:ethyl acetate:THF = 20:1:1 (v / v) to give compound P6 (5.0 g).

[0200] Mass spectrometry analysis of compound P6 yielded a mass-to-charge ratio (m / z) of 791.30.

[0201] For other compounds whose specific synthesis methods are not listed, they can be synthesized by referring to the above examples and combining them with common knowledge in the field.

[0202] The specific structures of some of the compounds used in the following application examples and comparative application examples of this invention are as follows:

[0203]

[0204]

[0205] Application Example 1

[0206] This application example provides a green organic electroluminescent device, using the compound provided by this invention as the host material of the light-emitting layer. The structure of the green organic electroluminescent device is as follows:

[0207] ITO / HT-1(80nm) / EB-1(20nm) / Main material: PGD-1[4%](35nm) / ETL-1(25nm) / LiF(0.5nm) / Al(150nm).

[0208] The fabrication method of the green organic electroluminescent device is as follows:

[0209] The material was placed inside a vacuum chamber, and the vacuum was evacuated to 1×10⁻⁶. -5 ~1×10 -6 Pa is sequentially vacuum-deposited onto a cleaned ITO substrate to fabricate OLED devices.

[0210] PGD-1 [4%] refers to the doping ratio of the dye, that is, the volume ratio of the host material to the dye PGD-1 is 96:4; HT-1 is the hole transport material and EB-1 is the electron blocking layer.

[0211] The main material of the light-emitting layer of the green organic electroluminescent device provided in this application example is compound P1.

[0212] Application Example 2-7, Comparison with Application Example 1-3

[0213] Application Examples 2-7 and Comparative Application Examples 1-3 each provide a green organic electroluminescent device. The only difference from Application Example 1 is that the main material of the light-emitting layer is replaced with other compounds (see Table 2 below). The other preparation steps and conditions are the same as in Application Example 1.

[0214] Performance testing

[0215] The driving voltage, luminance, current efficiency, and LT95 of the organic electroluminescent devices provided above were tested. The driving voltage and current efficiency were measured at a luminance of 1000 cd / m². 2The corresponding value, LT95, refers to maintaining an initial device current density of 10 mA / cm². 2 The time required for the device efficiency to drop to 95% of the efficiency corresponding to the initial current density, while remaining constant, is the time. The drive voltage, current efficiency, and LT95 are relative values. Specific test results are shown in Table 2 below:

[0216] Table 2

[0217]

[0218]

[0219] As can be seen from the above, the present invention designs the structure of carbazole compounds to make them suitable as the main material of the phosphorescent light-emitting layer of organic electroluminescent devices, so that the organic electroluminescent devices have lower driving voltage, higher current efficiency and longer lifespan.

[0220] As can be seen from Application Example 5, when Ar1 in Formula I is selected from dibenzofuranyl, using this carbazole compound as the main material of the organic electroluminescent device results in a lower driving voltage for the prepared organic electroluminescent device.

[0221] As can be seen from Application Example 6, when Ar1 in Formula I is selected from carbazole group, the organic electroluminescent device prepared by using this carbazole compound as the main material of the organic electroluminescent device has a high current efficiency.

[0222] Compare Application Example 8 with Application Example 4

[0223] Application Example 8 and Comparative Application Example 4 each provide a green organic electroluminescent device. The only difference from Application Example 1 is that the main material of the light-emitting layer has two components, and the volume ratio of the two components is 1:1 (see Table 3 below). The other preparation steps and conditions are the same as those in Application Example 1.

[0224] Performance testing

[0225] The luminance, current efficiency, and LT95 of the organic electroluminescent devices provided above were tested. The current efficiency is defined as the luminance at 1000 cd / m². 2 The corresponding value, LT95, refers to maintaining an initial device current density of 10 mA / cm². 2 The time required for the device efficiency to drop to 95% of the efficiency corresponding to the initial current density, while remaining constant, is used. Current efficiency and LT95 are relative values. Specific test results are shown in Table 3 below:

[0226] Table 3

[0227] Main material 1 Main material 2 <![CDATA[Brightness / (cd / m 2 )]]> Current efficiency LT95 Application Example 8 P1 H-13 1000 1 1 Comparative Application Example 4 D1 H-13 1000 0.87 0.78

[0228] As can be seen from the above, this invention designs the structure of carbazole compounds to make them suitable as one of the main materials for the phosphorescent light-emitting layer of organic electroluminescent devices, thereby enabling organic electroluminescent devices to have high current efficiency and long lifespan.

[0229] In summary, by designing the structure of carbazole compounds, this invention makes them suitable as the main material for the phosphorescent light-emitting layer of organic electroluminescent devices, thereby enabling the organic electroluminescent devices to have lower driving voltage, higher current efficiency, and longer lifespan.

[0230] The applicant declares that the detailed process flow of this invention is illustrated by the above embodiments, but this invention is not limited to the above detailed process flow, that is, it does not mean that this invention must rely on the above detailed process flow to be implemented. Those skilled in the art should understand that any improvements to this invention, equivalent substitutions of raw materials for the product of this invention, addition of auxiliary components, and selection of specific methods, etc., all fall within the protection scope and disclosure scope of this invention.

Claims

1. A carbazole-based compound, characterized by, The carbazole compound has a structure shown in formula I as follows: Ar1, Ar2, Ar3 are each independently selected from any one of C6-C40 aryl or C6-C30 heteroaryl; A1, A2, A3 are each independently selected from N or CR, and at least one is selected from N; R is selected from any one of -H, -CN, C6-C20 aryl or C1-C12 alkyl; The hydrogen atoms in the compound of formula I can each independently be substituted by deuterium atoms.

2. The carbazole compound according to claim 1, characterized by The compound of formula I includes a compound having a structure shown in formula I-1 as follows: Ar1, Ar2, Ar3, A1, A2, A3 have the same definitions as claim 1.

3. The carbazole compound according to claim 1 or 2, characterized by The C6-C40 aryl is selected from any one of phenyl, biphenyl, terphenyl, naphthyl, anthryl, phenanthryl, fluorenyl, benzofluorenyl, dibenzofluorenyl, naphthofluorenyl, pyrenyl, perylenyl, spirofluorenyl, triphenylenyl, fluoranthenyl, hydride benzanthracene, indenofluorenyl, benzindenofluorenyl, dibenzindenofluorenyl, naphthofluorenyl, tetraphenylmethane, or benzonaphthofluorenyl, or a combination of at least two thereof; Preferably, the C6-C30 heteroaryl is selected from any one of carbazolyl, dibenzothiophenyl, dibenzofuranyl, naphthobenzofuranyl, naphthobenzothiophenyl, dinaphthofuranyl, dinaphthothiophenyl, or a combination of at least two thereof; Preferably, the C6-C20 aryl is selected from any one of phenyl, naphthyl, biphenyl, anthryl, phenanthryl, fluorenyl, triphenylenyl, or fluoranthenyl; Preferably, the C1-C12 alkyl is selected from any one of methyl, ethyl, propyl, n-butyl, t-butyl, cyclopentyl, cyclohexyl, octyl, adamantyl.

4. The carbazole compound according to any one of claims 1 to 3, characterized by Ar1, Ar2, Ar3 are each independently selected from at least one of phenyl, carbazolyl, naphthyl, 9,9-dimethylfluorenyl, dibenzothiophenyl, biphenyl, dibenzofuranyl, triphenylenyl, or fluoranthenyl; Preferably, Ar1 is selected from any one of phenyl, naphthyl, biphenyl, dibenzofuranyl, dibenzothiophenyl, or carbazolyl; Preferably, Ar2, Ar3 are each independently selected from any one of phenyl, biphenyl, naphthyl, carbazolyl, dibenzofuranyl, phenyl-substituted carbazolyl, or a combination of at least two thereof; Preferably, Ar1, Ar2, Ar3 are each independently selected from any one of phenyl, bipheny, or naphthyl; Preferably, Ar1, Ar2, Ar3 are each selected from phenyl; Preferably, Ar1 is dibenzofuranyl; Preferably, Ar1 is carbazolyl; Preferably, any one of A1, A2, A3 is selected from N, and the other two are selected from CR, and R is selected from H; Preferably, any two of A1, A2, A3 are selected from N, and the other one is selected from CR, and R is selected from H; Preferably, A1, A2, A3 are each selected from N.

5. The carbazole compound according to any one of claims 1 to 4, wherein 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 compound can each independently be substituted by deuterium atoms; preferably, the carbazole compound is selected from any one of the following compounds: The substituent is that the hydrogen atom in the carbazole compound is independently substituted by deuterium atom.

6. An intermediate characterized by, The intermediate includes the following compounds: The intermediate is used for preparing the carbazole compound according to any one of claims 1-5.

7. A composition characterized in that, The composition includes a first component and a second component; The first component includes the carbazole compound according to any one of claims 1-5; The second component includes compound A; The compound A is obtained by fusing the group of structure shown in formula I-A with the group of structure shown in formula I-B at any adjacent two carbon atoms on ring A: Wherein, * represents the fusing site; X is selected from O, S, R 301 , R 302 are each independently selected from C1-C6alkyl, C6-C30aryl or C6-C20heteroaryl, and R 301 , R 302 may be linked via a single bond into a ring, R 303 is selected from C6-C30aryl or C6-C20heteroaryl, the dotted line indicates the point of attachment; Ar 22 selected from C6-C30aryl or C6-C20heteroaryl; The hydrogen atom in the compound A is independently substituted by at least one of -F, -CN, C6-C20 aryl, C1-C6 alkyl, C1-C6 alkoxy.

8. The composition of claim 7, wherein, said R 303 , Ar 22 each independently is selected from any one or a combination of at least two of the following substituted or unsubstituted groups: phenyl, biphenyl, naphthyl, anthryl, phenanthryl, fluorenyl, benzofluorenyl, dibenzofluorenyl, triphenylenyl, fluoranthenyl, pyrenyl, perylenyl, spirofluorenyl, dibenzofuranyl, dibenzothiophenyl, naphthobenzofuranyl, naphthobenzothiophenyl, dinaphthofuranyl, dinaphthothiophenyl, hydrogenated benzanthracenyl, indenofluorenyl, indolocarbazolyl, indenocarbazolyl, terphenyl, quaterphenyl, imidazolyl, benzimidazolyl, pyridyl, pyrimidyl, piperazinyl, quinolyl, isoquinolyl, quinoxalyl, quinazolyl, benzoquinoxalyl, benzoquinazolinyl, N-heterophenanthryl, diazaphenanthryl, carbazolyl, benzocarbazolyl, naphthocarbazolyl, dibenzocarbazolyl, triazinyl; The substituent is at least one of C1-C12 alkyl, C1-C12 alkoxy, C6-C12 aryl; Preferably, said R 303 , Ar 22 are each independently selected from any one or a combination of at least two of the following substituted or unsubstituted groups: phenyl, biphenyl, naphthyl, phenanthryl, anthryl, 9,9-dimethylfluorenyl, 9,9-diphenylfluorenyl, spirofluorenyl, dibenzofuranyl, dibenzothiophenyl, triphenylenyl, fluorenyl, benzofluorenyl, carbazolyl; The substituent is at least one of methyl, ethyl, tert-butyl, adamantyl, cyclohexyl, cyclopentyl, 1-methylcyclopentyl, 1-methylcyclohexyl, methoxy, phenyl, biphenyl, 9,9-dimethylfluorenyl, dibenzofuranyl, dibenzothiophenyl or naphthyl; Preferably, X is selected from O, S; Preferably, said R 301 , R 302 are each independently selected from methyl or phenyl; Preferably, said R 303 is selected from any one of phenyl, biphenyl or terphenyl; Preferably, said Ar 22 is selected from any one of a biphenyl, terphenyl or quaterphenyl group; Preferably, said R 303 is phenyl, said Ar 22 is selected from any one of biphenyl, terphenyl or quaterphenyl; Preferably, said R 303 is biphenyl, said Ar 22 is selected from biphenyl or terphenyl.

9. The composition according to claim 7 or 8, characterized in that, The compound A has a structure shown in any one of formula I-1 to I-30: wherein R 303 , Ar 22 have the same definition as in claim 7; The hydrogen atom in the compound of formula I-1 to I-30 is independently substituted by at least one of -F, -CN, C6-C20 aryl, C1-C6 alkyl, C1-C6 alkoxy; Preferably, the compound A is selected from any one of the following compounds: Preferably, the compound A is selected from any one of the following compounds:

10. An organic electroluminescent device, characterized by The organic electroluminescent device includes an anode, a cathode and an organic thin film layer disposed between the anode and the cathode; The organic thin film layer material includes the carbazole compound according to any one of claims 1-5 and / or the composition according to any one of claims 7-9; Preferably, the organic thin film layer includes an emitting layer, and the host material of the emitting layer includes the carbazole compound according to any one of claims 1-5 and / or the composition according to any one of claims 7-9; Preferably, the emitting layer is a phosphorescent emitting layer; Preferably, the organic electroluminescent device is a green organic electroluminescent device.

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