Nitrogen-containing compound, intermediate and organic electroluminescent device

Abstract

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

Description

Technical Field

[0001] The present invention belongs to the technical field of organic electroluminescent materials, and specifically relates to a nitrogen-containing compound, an intermediate, and an organic electroluminescent device, and more specifically relates to a nitrogen-containing compound, an intermediate, and an organic electroluminescent device used in an organic electroluminescent device. Background Art

[0002] The structure of an organic electroluminescent device is specifically: an anode, a cathode, and an organic layer therebetween. 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. Electron transport materials and hole injection materials, hole transport materials or hole blocking layers are major obstacles to the full practical application of OLED technology, which directly limits the luminous efficiency, service life, and operating voltage of the device.

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

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

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

[0007]

[0008] Among them, Ar 1 ,Ar 2 ,Ar 3 Each is independently selected from C6-C40 aryl or C6-C30 heteroaryl;

[0009] m and n are each independently selected from integers between 0 and 4;

[0010] X, Y, and Z are each independently selected from N or CR, and at least one of X, Y, and Z is selected from N; R is selected from any one of an H atom, a C6-C20 aryl group, or a C1-C12 alkyl group;

[0011] Ar 1 ,Ar 2 ,Ar 3 The hydrogen atoms in can each be replaced by deuterium atoms independently;

[0012] The hydrogen atoms in the compound of formula I may each independently be substituted by at least one of -F, -CN, C6-C20 aryl, C6-C30 heteroaryl, C1-C12 alkyl or C1-C12 alkoxy.

[0013] In the present invention, the structure of the nitrogen-containing 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 higher current efficiency, longer life and lower driving voltage.

[0014] In the present invention, C6-C40 can be C6, C8, C10, C12, C16, C20, C24, C28, C30, C32, C36 or C40, etc.

[0015] C6-C30 can be C6, C8, C10, C12, C16, C20, C24, C28 or C30, etc.

[0016] C6-C20 can be C6, C8, C10, C12, C16 or C20, etc.

[0017] C1-C12 (for example, may be C1, C2, C3, C4, C5, C6, C7, C8, C9, C10, C11 or C12.

[0018] It should be noted that, unless otherwise specified in the present invention, -D is a deuterium atom, and -H and hydrogen refer to protium, and the same applies hereinafter.

[0019] 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.

[0020] As a preferred technical solution of the present invention, the C6-C40 aryl group is selected from phenyl, biphenyl, terphenyl, naphthyl, anthracenyl, phenanthrenyl, fluorenyl, benzofluorenyl, dibenzofluorenyl, naphthanefluorenyl, pyrenyl, peryl, spirofluorenyl, triphenylene, fluoranthenyl, hydrogenated benzanthryl, indenofluorenyl, benzoindenofluorenyl, dibenzoindenofluorenyl, naphthanefluorenyl, tetraphenylmethane ( The dotted line indicates the connection site) or any one of benzonaphthofluorenyl or a combination of at least two thereof.

[0021] As a preferred technical solution of the present invention, the C6-C30 heteroaryl group is selected from any one of a carbazolyl group, a dibenzothiophenyl group, a naphthobenzofuranyl group, a naphthobenzothiophenyl group, a dinaphthofuranyl group, and a dinaphthothiophenyl group.

[0022] As a preferred technical solution of the present invention, the C6-C20 aryl group is selected from any one of phenyl, biphenyl, terphenyl, naphthyl, anthracenyl, phenanthryl, fluorenyl, triphenylene or fluoranthene.

[0023] As a preferred technical solution of the present invention, the C1-C12 alkyl group is selected from any one of methyl, ethyl, propyl, butyl, pentyl, hexyl, octyl, heptyl or decyl.

[0024] As a preferred technical solution of the present invention, the C1-C12 alkoxy group is selected from any one of methoxy, ethoxy, propoxy, butoxy, pentyloxy or hexyloxy.

[0025] As a preferred technical solution of the present invention, the Ar 1 ,Ar 2 ,Ar 3 Each is independently selected from any one of phenylene, carbazolylene, biphenylene, fluorenylene, naphthylene, triphenylene, fluoranthenylene, indenofluorenylene, dibenzothienylene, naphthobenzofuranylene, naphthobenzothienylene or carbazolyl;

[0026] The Ar 1 ,Ar 2 ,Ar 3 The hydrogen atoms in the ion can be replaced by deuterium atoms independently.

[0027] Preferably, the Ar 1 ,Ar 2 ,Ar 3 Each is independently selected from at least one of phenyl, carbazolyl, naphthyl, 9,9-dimethylfluorenyl, dibenzothiophenyl, dibenzofuranyl and diphenyl;

[0028] The Ar 1 ,Ar 2 ,Ar 3 The hydrogen atoms in the ion can be replaced by deuterium atoms independently.

[0029] As a preferred technical solution of the present invention, X, Y, and Z are all selected from N.

[0030] Preferably, X is selected from CR, and Y and Z are both selected from N.

[0031] Preferably, X and Y are each independently selected from CR, and Z is selected from N.

[0032] Preferably, R is selected from H.

[0033] As a preferred technical solution of the present invention, m and n are both selected from 0.

[0034] Preferably, m and n are both selected from 1.

[0035] Preferably, m+n is selected from 1.

[0036] Preferably, m is selected from 0, and n is selected from 1.

[0037] Preferably, m is selected from 0, and n is selected from 2.

[0038] 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 -F, -CN, phenyl, naphthyl, biphenyl, carbazolyl, methyl, ethyl, propyl, butyl, methoxy, ethoxy, propoxy or butoxy.

[0039] Preferably, the hydrogen atoms in the compound of formula I may be independently substituted by at least one of -F, -CN, phenyl, naphthyl, carbazolyl, methyl, ethyl, tert-butyl, triphenylmethyl, and triphenylsilyl.

[0040] As a preferred technical solution of the present invention, the nitrogen-containing compound is selected from any one of the following substituted or unsubstituted compounds:

[0041]

[0042]

[0043] Wherein, substitution refers to the corresponding Ar 1 ,Ar 2 ,Ar 3 The hydrogen atoms at the positions can be independently replaced by deuterium atoms. Preferably, the nitrogen-containing compound is selected from the following compounds:

[0044]

[0045] It should be noted that the present invention has no special restrictions on the specific synthesis method of nitrogen-containing compounds, and the commonly used synthesis methods in the art are applicable, including but not limited to: the compounds provided by the present invention can be prepared by the following general formula:

[0046]

[0047] Among them, X 1 , X 2Each is independently selected from any one of -F, -Cl, -Br, -I;

[0048] X, Y, Z, Ar 1 ,Ar 2 ,Ar 3 , m, and n have the same definitions as above.

[0049] In a second aspect, the present invention provides an intermediate, wherein the intermediate comprises a compound represented by the following formula MA:

[0050]

[0051] Among them, X 2 has the same definition as above;

[0052] The intermediate is used to prepare the nitrogen-containing compound as described in the first aspect.

[0053] Preferably, the intermediate includes the following compounds:

[0054]

[0055] 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;

[0056] The organic thin film layer material includes the nitrogen-containing compound as described in the first aspect.

[0057] 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 nitrogen-containing compound as described in the first aspect.

[0058] Preferably, the light-emitting layer is a phosphorescent light-emitting layer.

[0059] As a preferred technical solution of the present invention, the organic electroluminescent device is a blue light organic electroluminescent device.

[0060] 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.

[0061] 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, and a yellow phosphorescent light-emitting layer.

[0062] 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%.

[0063] 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:

[0064]

[0065] Wherein, M is selected from any one of Ir, Pt, Pd, Os, Ti, Zr, Hf, Eu, Tb, Tm, Cu or Au;

[0066] Y 1 -Y 4 are each independently selected from carbon or nitrogen;

[0067] Y 1 and Y 2 They can be connected by single or double bonds. 3 and Y 4 They can be connected by single or double bonds;

[0068] Cy 1 and Cy 2 Each is 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, triazinyl, dibenzothienyl, N-heterocarbazolyl, wherein Cy 1 and Cy 2 may optionally be linked to each other via a single bond or an organic linking group;

[0069] 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;

[0070] R 91 and R 92Each is independently selected from -H, -D, -F, -Cl, -Br, -I, hydroxyl, cyano, nitro, amino, amidine, hydrazine, hydrazone, carboxylic acid, carboxylate, sulfonic acid, sulfonate, phosphoric acid, phosphate, -SF 5 , substituted or unsubstituted C1-C60 (for example, C1, C5, C10, C15, C20, C25, C30, C35, C40, C45, C50, C55 or C60, etc.) alkyl, substituted or unsubstituted C2-C60 (for example, C2, C5, C10, C15, C20, C25, C30, C35, C40, C45, C50, C55 or C60, etc.) alkenyl, substituted or unsubstituted C2-C60 (e.g., C2, C5, C10, C15, C20, C25, C30, C35, C40, C45, C50, C55, or C60, etc.) alkynyl, substituted or unsubstituted C1-C60 (e.g., C1, C5, C10, C15, C20, C25, C30, C35, C40, C45, C50, C55, or C60, etc.) alkoxy, substituted or unsubstituted 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, etc.) aryl, substituted or unsubstituted C6-C60 (for example, C6, C12, C15, C18, C24, C30, C32, C36, C40, C42, C54 or C60, etc.) any one of a C24, C30, C32, C36, C40, C42, C54 or C60 (e.g., C24, C30, C32, C36, C40, C42, C54 or C60, etc.) aryloxy group, a substituted or unsubstituted C6-C60 (e.g., C6, C12, C15, C18, C24, C30, C32, C36, C40, C42, C54 or C60, etc.) arylthio group, a substituted or unsubstituted monovalent non-aromatic fused polycyclic group, and a substituted or unsubstituted monovalent non-aromatic fused heteropolycyclic group.

[0071] a 1 and a 2 Each is independently an integer selected from 1-5, for example, 1, 2, 3, 4 or 5;

[0072] b is an integer selected from 0-4, for example, 0, 1, 2, 3 or 4;

[0073] a is selected from 1, 2 or 3;

[0074] L 1 It is a monovalent organic ligand, a divalent organic ligand or a trivalent organic ligand.

[0075] Preferably, the compound of formula PD is selected from any one of the following compounds:

[0076]

[0077]

[0078]

[0079]

[0080] 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.

[0081] 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.

[0082] 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:

[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 ,Ar 42Each 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]

[0094]

[0095] 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:

[0096]

[0097] 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;

[0098] 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;

[0099] Ar is selected from any one of triphenylene, fluoranthenylene, dibenzofuranylene or dibenzothiophenylene;

[0100] Ar 1 and Ar 2 Each is 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;

[0101] Ar 1 Between Ar and Ar 2 and Ar 1 ,Ar 2 Each of them can be independently connected by a single bond, O, S, CR 1 R 2 , NR connection or bridging.

[0102] R, R 1 , R 2 Each is independently selected from any one of C1-C20 (for example, C1, C2, C4, C6, C8, C10, C12, C14, C16, C18 or C20, etc.) alkyl, C6-C40 (for example, C6, C8, C10, C12, C16, C20, C24, C28, C30, C32, C36 or C40, etc.) aryl, dibenzofuranyl or dibenzothiophenyl;

[0103] 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.

[0104] Preferably, Ar is a fluoranthenyl group, and m+n>1.

[0105] 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.

[0106] Preferably, the L, Ar 1 ,Ar 2Each is independently selected from at least one of phenyl, biphenyl, naphthyl, phenanthryl, anthracenyl, fluorenyl, benzofluorenyl, dibenzofluorenyl, triphenylene, fluoranthenyl, pyrenyl, peryl, spirofluorenyl, indenofluorenyl and hydrogenated benzanthryl.

[0107] Preferably, the compound of formula IB is selected from the following structures:

[0108]

[0109] Wherein, L is phenylene;

[0110] Ar 1 ,Ar 2 , m have the same definitions as above.

[0111] Preferably, the compound of formula IB is selected from any one of the following compounds:

[0112]

[0113]

[0114]

[0115] 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.

[0116] The triarylamine compound or the carbazole compound is used as the hole layer material, and the hole layer material includes the following structure:

[0117]

[0118] Among them, Ar 601 ~Ar 609Each 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;

[0119] 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;

[0120] 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 702 Can connect via one-touch.

[0121] 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.

[0122] 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.

[0123] In the present invention, there is no special restriction on the electron transport layer material, which exemplarily includes but is not limited to:

[0124]

[0125]

[0126]

[0127]

[0128]

[0129]

[0130] 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.

[0131] Alternatively, a thin intermediate layer of a material with a high dielectric constant may be introduced between the metal cathode and the organic semiconductor to form a multilayer structure; the material with a high dielectric constant may also be referred to as an electron injection material, and may be selected from fluorides of alkali metals or alkaline earth metals, and corresponding oxides or carbonates (e.g., LiF, Li 2 O.BaF 2 、MgO、NaF、CsF、Cs 2 CO 3 etc.) or lithium quinolate (LiQ).

[0132] Compared with the prior art, the present invention has the following beneficial effects:

[0133] In the present invention, the structure of the nitrogen-containing 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 higher current efficiency, longer life and lower driving voltage. DETAILED DESCRIPTION

[0134] 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.

[0135] Preparation Example 1 Synthesis of Intermediate M1

[0136] This preparation example provides an intermediate M1 and a synthesis method thereof, and the synthesis method is as follows:

[0137]

[0138] Under nitrogen protection, deuterated m-dibromobenzene (2.4 g) and tetrahydrofuran (60 mL) were added to a three-necked flask, and then the temperature was lowered to -78°C, and 0.01 mol of butyl lithium in n-hexane solution (concentration 1.6 M, 6.3 mL) was slowly added, and then -78°C to -60°C was maintained for 30 min, and a tetrahydrofuran solution containing 2.9 g of compound M1-1, 0.0001 mol Pd(dba)2, and 0.0001 mol of anhydrous nickel chloride were added. The temperature was slowly raised to room temperature for reaction for 2 h, and then raised to reflux for reaction for 2 h, and the temperature was lowered, and water and toluene were added for separation. The organic layer was washed with water until neutral, dried over anhydrous magnesium sulfate, and after filtering out the desiccant, it was concentrated to dryness, separated by silica gel column chromatography, and eluted with petroleum ether to obtain intermediate M1 (2.1 g).

[0139] The obtained intermediate M1 was subjected to mass spectrometry detection, and its mass-to-charge ratio m / z was tested to be 416.05.

[0140] Preparation Example 2 Synthesis of Intermediate M2

[0141] This preparation example provides an intermediate M2 and a synthesis method thereof, and the synthesis method is as follows:

[0142]

[0143] Referring to the synthesis method of intermediate M1, intermediate M2 was prepared.

[0144] The obtained intermediate M2 was subjected to mass spectrometry detection, and its mass-to-charge ratio m / z was tested to be 416.05.

[0145] Synthesis Example 1 Synthesis of Compound P1

[0146] This synthesis example provides compound P1 and its synthesis method, and its synthesis method is as follows:

[0147]

[0148] Under nitrogen protection, add intermediate M1 (4.1 g) and tetrahydrofuran (80 mL) to a three-necked flask, then cool to -78 ° C, slowly add 0.01 mol of butyl lithium in n-hexane solution (concentration 1.6 M, 6.3 mL), then keep -78 ° C to -60 ° C for 30 min, add 3.6 g of intermediate P1-1 in tetrahydrofuran solution, 0.0001 mol Pd (dba) 2, 0.0001 mol of anhydrous nickel chloride, slowly heat to room temperature to react for 2 hours, then heat to reflux to react for 4 hours, cool, add water and toluene for separation, wash the organic layer with water until neutral, dry with anhydrous magnesium sulfate, filter out the desiccant, concentrate to dryness, separate by silica gel column chromatography, and elute with petroleum ether: dichloromethane: tetrahydrofuran = 10:2:3 (volume ratio) to obtain compound P1 (2.1 g).

[0149] The obtained compound P1 was subjected to mass spectrometry detection, and its mass-to-charge ratio m / z was tested to be 663.28.

[0150] Synthesis Example 2-9

[0151] Synthesis Examples 2-9 respectively provide a compound and a synthesis method thereof. The synthesis method of the corresponding compound refers to the synthesis method of compound P1 provided in Synthesis Example 1. Raw material 1 and raw material 2 are reacted to synthesize the corresponding compound (see Table 1 below for details), and mass spectrometry is performed to measure the mass-to-charge ratio (m / z) as shown in Table 1.

[0152] Table 1

[0153]

[0154]

[0155]

[0156] 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.

[0157] The specific structures of some compounds used in the following application examples and comparative application examples of the present invention are as follows:

[0158]

[0159]

[0160] Application Example 1

[0161] This application example provides a blue 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 blue light organic electroluminescent device is:

[0162] ITO / HT-1: HI-2 [5%] (80nm) / HT-1 (30nm) / EB-1 (20nm) / host material: PBD-1 [5%] (35nm) / ETL-1 (25nm) / LiF (0.5nm) / Al (150nm).

[0163] The preparation method of the blue light organic electroluminescent device is as follows:

[0164] 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 turn to prepare an OLED device.

[0165] Among them, PBD-1[5%] refers to the doping ratio of the dye, that is, the volume ratio of the main material to the dye PBD-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.

[0166] The main material of the light-emitting layer of the blue light organic electroluminescent device provided in this application example is compound P1.

[0167] Application Example 2-4

[0168] Application Examples 2-4 respectively provide a blue light organic electroluminescent device, which differs from Application Example 1 only in that the main material of the light-emitting layer is replaced by other compounds (see Table 2 for details), and the other preparation steps and conditions are the same as those of Application Example 1.

[0169] Comparative Application Example 1-2

[0170] Comparative Application Examples 1-2 respectively provide an organic electroluminescent device, which differs from Application Example 1 only in that the main material of the light-emitting layer is different (see Table 2 for details), and the other preparation steps and conditions are the same as those of Application Example 1.

[0171] Performance Testing

[0172] The OLED-1000 multi-channel accelerated aging life and light color performance analysis system produced by Hangzhou Yuanfang was used to test the brightness, driving voltage, current efficiency and LT95 of the organic electroluminescent devices provided above. The voltage and current efficiency are based on the brightness of 1000cd / 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, where the driving voltage, current efficiency and LT95 are relative values. The specific test results are shown in Table 2:

[0173] Table 2

[0174] Main material <![CDATA[Luminance / (cd / m 2 )]]> Driving voltage Current efficiency LT95 Application Example 1 P3 1000 0.98 1.02 1.06 Application Example 2 P5 1000 1.02 1.09 1.11 Application Example 3 P6 1000 1.01 1.19 1.09 Application Example 4 P9 1000 0.87 / / Comparative application example 1 D2 1000 1 1 1 Comparative Application Example 2 D3 1000 1.01 0.98 1.05

[0175] The " / " indicates that there is no data.

[0176] Compared with the compounds D2 and D3 in the comparative application examples 1-2, the benzene ring between the triazine ring and the silicon atom is affected by the strong electron-withdrawing ability of the triazine ring. If the H atom is connected to it, the acidity of the hydrogen atom is stronger, and it is also relatively unstable when it is prepared into a device, thereby affecting the current efficiency and life of the organic electroluminescent device. After changing it to a D atom, the CD bond is more stable, which can improve the life of the organic electroluminescent device. In addition, in the compound P3, the deuterated position is in the relatively middle part of the entire molecular structure, which slightly changes the polarity of the molecule, thereby improving the film-forming property, making the charge migration ability of the compound P3 stronger, and improving the voltage and efficiency of the organic electroluminescent device.

[0177] However, in compound D3, another benzene ring connected to the silicon atom is also deuterated, which wastes deuterium atoms and increases the cost of the material. At the same time, the increase in deuterium atoms increases the driving voltage of the organic electroluminescent device, reduces the current efficiency of the organic electroluminescent device, and the lifespan is not further improved.

[0178] The deuterated position in compound D2 is located at a relatively edge of the entire molecular structure and does not improve the performance of the material when prepared into an organic electroluminescent device.

[0179] From the above content, it can be seen that the structure of the nitrogen-containing compound in the present invention 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 higher current efficiency and longer life and lower driving voltage.

[0180] Application Examples 5-8, Comparative Application Example 3

[0181] Application Examples 5-8 and Comparative Application Example 3 respectively provide an organic electroluminescent device, which differs from Application Example 1 only in that the main material of the light-emitting layer is different (see Table 3 for details), and the other preparation steps and conditions are the same as those of Application Example 1.

[0182] Performance Testing

[0183] The OLED-1000 multi-channel accelerated aging life and light color performance analysis system produced by Hangzhou Yuanfang was used to test the brightness, driving voltage, current efficiency and LT95 of the organic electroluminescent devices provided above. The voltage and current efficiency are based on the brightness of 1000cd / 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, where the driving voltage, current efficiency and LT95 are relative values. The specific test results are shown in Table 3:

[0184] Table 3

[0185] Main material <![CDATA[Brightness / (cd / m 2 )]]> Driving voltage Current efficiency LT95 Application Example 5 P1 1000 1.02 1.08 1.32 Application Example 6 P2 1000 0.98 1.02 1.09 Application Example 7 P4 1000 1.04 1.09 1.11 Application Example 8 P8 1000 0.81 1.11 1.02 Comparative Application Example 3 D1 1000 1 1 1

[0186] Compared with the compound D1 in the comparative application example 3, the benzene ring between the triazine ring and the silicon atom is affected by the strong electron-withdrawing ability of the triazine ring. If the H atom is connected to it, the acidity of the hydrogen atom is stronger, and it is also relatively unstable when it is prepared into a device, thereby affecting the current efficiency and life of the organic electroluminescent device. After changing it to a D atom, the CD bond is more stable, which can improve the life of the organic electroluminescent device. In addition, in the compound P2, the deuterated position is in the relatively middle part of the entire molecular structure, which slightly changes the polarity of the molecule, thereby improving the film-forming property, making the charge migration ability of the compound P2 stronger, and improving the voltage and efficiency of the organic electroluminescent device.

[0187] However, in compound D1, the deuterated form of another benzene ring to which the silicon atom is connected does not improve the performance of the material when prepared into an organic electroluminescent device.

[0188] From the above content, it can be seen that the structure of the nitrogen-containing compound in the present invention 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 higher current efficiency and longer life and lower driving voltage.

[0189] Application Examples 9-11

[0190] Application Examples 9-11 respectively provide an organic electroluminescent device, which differs from Application Example 1 only in that the main material of the light-emitting layer is different (see Table 4 for details), and the other preparation steps and conditions are the same as those of Application Example 1.

[0191] Performance Testing

[0192] The OLED-1000 multi-channel accelerated aging life and light color performance analysis system produced by Hangzhou Yuanfang was used to test the brightness, driving voltage, current efficiency and LT95 of the organic electroluminescent devices provided above. The voltage and current efficiency are based on the brightness of 1000cd / 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, where the driving voltage, current efficiency and LT95 are relative values. The specific test results are shown in Table 4:

[0193] Table 4

[0194] Main material <![CDATA[Luminance / (cd / m 2 )]]> Driving voltage Current efficiency LT95 Application Example 9 P7 1000 1 1 1 Application Example 10 P10 1000 1.02 1.22 0.87 Application Example 11 P11 1000 1.04 1.26 1.06

[0195] From the above content, it can be known that the structure of the 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 higher current efficiency and longer life.

[0196] In summary, the present invention designs the structure of the 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 higher current efficiency and longer life.

[0197] 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 nitrogen-containing compound, characterized in that The nitrogen-containing compound has a structure as shown in the following formula I: wherein Ar1, Ar2, and Ar3 are each independently selected from a C6-C40 aryl group or a C6-C30 heteroaryl group; m and n are each independently selected from integers between 0 and 4; X, Y, and Z are each independently selected from N or CR, and at least one of X, Y, and Z is selected from N; R is selected from any one of an H atom, a C6-C20 aryl group, or a C1-C12 alkyl group; The hydrogen atoms in Ar1, Ar2, and Ar3 can each independently be replaced by deuterium atoms; The hydrogen atoms in the compound of formula I may each independently be substituted by at least one of -F, -CN, C6-C20 aryl, C6-C30 heteroaryl, C1-C12 alkyl or C1-C12 alkoxy.

2. The nitrogen-containing compound according to claim 1, 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 of carbazolyl, dibenzothiophenyl, naphthobenzofuranyl, naphthobenzothiophenyl, dinaphthofuranyl and dinaphthothiophenyl; Preferably, the C6-C20 aryl group is selected from any one of phenyl, biphenyl, terphenyl, naphthyl, anthracenyl, phenanthryl, fluorenyl, triphenylene or fluoranthenyl; Preferably, the C1-C12 alkyl group is selected from any one of methyl, ethyl, propyl, butyl, pentyl, hexyl, octyl, heptyl or decyl; Preferably, the C1-C12 alkoxy group is selected from any one of methoxy, ethoxy, propoxy, butoxy, pentyloxy or hexyloxy.

3. The nitrogen-containing compound according to claim 1 or 2, characterized in that Ar1, Ar2, and Ar3 are each independently selected from any one of phenylene, carbazolylene, biphenylene, fluorenylene, naphthylene, triphenylene, fluoranthenylene, indenofluorenylene, dibenzothienylene, naphthobenzofuranylene, naphthobenzothienylene, or carbazolyl; The hydrogen atoms in Ar1, Ar2, and Ar3 can each independently be replaced by a deuterium atom; Preferably, Ar1, Ar2, and Ar3 are each independently selected from at least one of phenyl, carbazolyl, naphthyl, 9,9-dimethylfluorenyl, dibenzothienyl, dibenzofuranyl, and diphenyl; The hydrogen atoms in Ar1, Ar2 and Ar3 can each independently be replaced by a deuterium atom.

4. The nitrogen-containing compound according to any one of claims 1 to 3, characterized in that Said X, Y, and Z are all selected from N; Preferably, X is selected from CR, and Y and Z are both selected from N; Preferably, X and Y are each independently selected from CR, and Z is selected from N; Preferably, R is selected from H.

5. The nitrogen-containing compound according to any one of claims 1 to 4, characterized in that The m and n are both selected from 0; Preferably, said m and n are both selected from 1; Preferably, said m+n is selected from 1; Preferably, m is selected from 0, and n is selected from 1; Preferably, m is selected from 0, and n is selected from 2.

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

7. The nitrogen-containing compound according to any one of claims 1 to 6, characterized in that The nitrogen-containing compound is selected from any one of the following substituted or unsubstituted compounds: Here, substitution means that the hydrogen atoms at the positions corresponding to Ar1, Ar2, and Ar3 can be replaced by deuterium atoms independently.

8. An intermediate, comprising a compound represented by the following formula MA: in, X2 is selected from any one of -F, -Cl, -Br, -I; The intermediate is used to prepare the nitrogen-containing compound according to any one of claims 1 to 7; Preferably, the intermediate includes 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 nitrogen-containing compound according to any one of claims 1 to 7; Preferably, the organic thin film layer comprises a light-emitting layer, and a main material of the light-emitting layer comprises the nitrogen-containing compound according to any one of claims 1 to 7.

10. The organic electroluminescent device according to claim 9, characterized in that: The light-emitting layer is a phosphorescent light-emitting layer; Preferably, the organic electroluminescent device is a blue organic electroluminescent device.

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