An organic electroluminescent material and its application

Abstract

The present invention relates to the field of display technologies, and particularly relates to an organic electroluminescent material and its application. The organic electroluminescent material provided by the present invention comprises a first host material and a second host material. The first host material comprises a compound represented by formula (I): #imgabs0# The second host material is a compound represented by formula (2): HAr-(L 1 -Ar 3 ) d , which can endow the organic electroluminescent device containing this material with more excellent lifespan, and also has a lower driving voltage and higher efficiency.

Description

Technical Field

[0001] The present invention relates to the field of display technology, and in particular to an organic electroluminescent material and application thereof. Background Art

[0002] Organic electroluminescent devices (OLEDs) convert electrical energy into light by applying power to organic electroluminescent materials, and generally include an anode, a cathode, and an organic layer formed between the two electrodes. The organic layer of an organic EL device may include a hole injection layer, a hole transport layer, a hole auxiliary layer, a luminescent auxiliary layer, an electron blocking layer, a luminescent layer (containing a host material and a dopant material), an electron buffer layer, a hole blocking layer, an electron transport layer, an electron injection layer, etc. The materials used in the organic layer may be divided into hole injection materials, hole transport materials, hole auxiliary materials, luminescent auxiliary materials, electron blocking materials, luminescent materials, electron buffer materials, hole blocking materials, electron transport materials, electron injection materials, etc. depending on their functions. In an organic EL device, holes from the anode and electrons from the cathode are injected into the luminescent layer by applying a voltage, and excitons with high energy are generated by the recombination of holes and electrons. The organic light-emitting compound moves to an excited state by energy and emits light by the energy when the organic light-emitting compound returns to the ground state from the excited state.

[0003] In the prior art, 4,4-N,N′-dicarbazolylbiphenyl (CBP) as an organic functional material has poor electron transport energy relative to its hole transport capacity, so the charge balance in the light-emitting layer is destroyed, and excess holes flow out to the cathode side, causing a decrease in the recombination probability in the light-emitting layer, thereby reducing the luminous efficiency. In the case of 8-hydroxyquinoline aluminum (Alq3) as an organic functional material, which is an electron transport material with a lower energy level of the lowest triplet excited state than Ir(ppy)3 (green light doping material-organic phosphorescent doping material), the luminous efficiency may also be reduced due to the transfer of triplet excitation energy from the dopant to the electron transport material.

[0004] In summary, due to the low stability of existing organic functional materials and unbalanced carrier mobility, the organic light-emitting diodes have the problems of high driving voltage and short life, which seriously limits the application of organic light-emitting diodes. Summary of the invention

[0005] The purpose of the present invention is to overcome the defects of organic electroluminescent diodes such as high driving voltage and short life caused by low stability and unbalanced carrier mobility of existing organic electroluminescent materials, and further provide an organic electroluminescent material and its application.

[0006] Definitions of substituent terms in this invention:

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

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

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

[0010] In the present invention, aryl and arylene groups include monocyclic, polycyclic or condensed-ring aromatic groups, the rings may be interrupted by short non-aromatic units, and may contain spiro structures. Aryl groups include but are not limited to phenyl, biphenyl, terphenyl, naphthyl, phenanthryl, anthracenyl, fluorenyl, spirobifluorenyl, etc., and arylene groups include but are not limited to phenylene, biphenylene, terphenylene, naphthyl, phenanthryl, anthracenyl, fluorenyl, spirobifluorenyl, etc.

[0011] In the present invention, heteroaryl and heteroarylide include monocyclic, polycyclic or condensed ring heteroaryl, and the rings may be interrupted by short non-aromatic units, and the heteroatoms include nitrogen, oxygen and sulfur. Heteroaryl includes, but is not limited to, furanyl, phenylthio, pyrrolyl, imidazolyl, pyrazolyl, thiazolyl, thiadiazolyl, isothiazolyl, isoxazolyl, oxazolyl, oxadiazolyl, triazinyl, tetrazinyl, triazolyl, tetrazolyl, furazolyl, pyridyl, pyrazinyl, pyrimidinyl, pyridazinyl, benzofuranyl, benzothiophenyl, isobenzofuranyl, dibenzofuranyl, dibenzothiophenyl, benzimidazolyl, benzo thiazolyl, benzisothiazolyl, benzisoxazolyl, benzoxazolyl, isoindolyl, indolyl, indazolyl, benzothiadiazolyl, quinolyl, isoquinolyl, cinnolinyl, quinazolinyl, quinoxalinyl, carbazolyl, phenoxazinyl, phenothiazinyl, phenanthridinyl, benzodioxolyl, dihydroacridinyl, and derivatives thereof; heteroarylene includes but is not limited to furanyl, phenylene thio, pyrroleyl yl, imidazolyl, pyrazolyl, thiazolyl, thiadiazolyl, isothiazolyl, isoxazolyl, oxazolyl, oxadiazolyl, triazinyl, tetrazinyl, triazolyl, tetrazolyl, furazolyl, pyridyl, pyrazinyl, pyrimidyl, pyridazinyl, benzofuranyl, benzothiophenylene, isobenzofuranyl, dibenzofuranyl, dibenzothiophenylene, benzimidazolyl, oxazolyl, benzothiazolyl, benzoisothiazolyl, benzoisoxazolyl, benzoxazolyl, isoindolyl, indolyl, indazolyl, benzothiadiazolyl, quinolyl, isoquinolyl, cinnolinyl, quinazolinyl, quinoxalinyl, carbazolyl, phenoxazinyl, phenothiazinyl, phenanthridinyl, benzodioxolyl, acridinyl, and derivatives thereof.

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

[0013] As used herein, unless otherwise specified, hydrogen atoms include protium, deuterium and tritium.

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

[0015] The scheme adopted by the present invention is as follows:

[0016] An organic electroluminescent material, comprising a first host material and a second host material, wherein the first host material comprises a compound represented by formula (1):

[0017]

[0018] Among them, R 1 -R 12 Each is independently selected from hydrogen, deuterium, halogen, cyano, substituted or unsubstituted C1-C30 alkyl, substituted or unsubstituted C3-C30 cycloalkyl, substituted or unsubstituted C5-C30 aryl, substituted or unsubstituted C3-C30 heteroaryl, substituted or unsubstituted C6-C30 arylamine;

[0019] R 13 , R 14 Each is independently selected from hydrogen, deuterium, substituted or unsubstituted C6-C30 aryl or substituted or unsubstituted C1-C20 alkyl;

[0020] The second host material comprises a compound represented by formula (2):

[0021] HAr-(L 1 -Ar 3 ) d Formula (2)

[0022] HAr is a substituted or unsubstituted C3-C30 heteroaryl group;

[0023] L 1 represents a single bond, a substituted or unsubstituted C6-C30 arylene group, or a substituted or unsubstituted C3-C30 heteroarylene group;

[0024] Ar 3 A substituted or unsubstituted C6-C30 aryl group, a substituted or unsubstituted C3-C30 heteroaryl group;

[0025] d is an integer from 1 to 3;

[0026] The substituents in the substituted C1-C30 alkyl, substituted C3-C30 cycloalkyl, substituted C3-C60 heteroaryl, substituted C6-C30 aromatic amino, substituted C6-C30 aryl, substituted C1-C20 alkyl, substituted C5-C30 aryl, substituted C6-C30 arylene and substituted C3-C30 heteroarylene are selected from one or a combination of two of deuterium, halogen, cyano, C1-C6 alkyl, C3-C30 cycloalkyl, C5-C12 aryl and C3-C12 heteroaryl.

[0027] Preferably, R 1 -R 12At least one of them is of the following formula (I) or formula (II):

[0028]

[0029] L1 and L2 are each independently selected from a single bond, a substituted or unsubstituted C6-C30 arylene group, or a substituted or unsubstituted C3-C30 heteroarylene group;

[0030] n is an integer from 0 to 5;

[0031] Ar 1 -Ar 2 Each is independently selected from hydrogen, deuterium, protium, tritium, halogen, cyano, substituted or unsubstituted C6-C30 arylamine, substituted or unsubstituted C3-C30 heteroarylamine, substituted or unsubstituted C6-C30 aryl, and substituted or unsubstituted C3-C30 heteroaryl;

[0032] Preferably, RT1-RT8 are each independently selected from hydrogen, deuterium, tritium, halogen, cyano, substituted or unsubstituted C1-C30 alkyl, substituted or unsubstituted C7-C30 aralkyl, substituted or unsubstituted C6-C30 aryl, substituted or unsubstituted C3-C30 heteroaryl, substituted or unsubstituted C4-C30 heteroaralkyl, substituted or unsubstituted C3-C30 cycloalkyl, substituted or unsubstituted C3-C30 heterocycloalkyl, substituted or unsubstituted C3-C30 cycloalkenyl, substituted or unsubstituted C1-C30 alkoxy, and substituted or unsubstituted C6-C30 aryloxy;

[0033] RT1-RT8 exist independently or are connected to form ring B, and ring B is a substituted or unsubstituted C6-C30 aromatic ring or a substituted or unsubstituted C3-C30 heteroaromatic ring;

[0034] The substituted C6-C30 arylene group, substituted C3-C30 heteroarylene group, substituted C6-C30 arylamine group, substituted C3-C30 heteroarylamine group, substituted C6-C30 aryl group, substituted C3-C30 heteroaryl group, substituted C1-C30 alkyl group, substituted C7-C30 aralkyl group, substituted C4-C30 heteroaralkyl group, substituted C3-C30 cycloalkyl group, substituted C The substituents in the C3-C30 heterocycloalkyl, substituted C3-C30 cycloalkenyl, substituted C1-C30 alkoxy, substituted C6-C30 aryloxy, substituted C6-C30 aromatic ring, substituted C3-C30 heteroaromatic ring are selected from one or a combination of two of deuterium, halogen, cyano, C1-C6 alkyl, C3-C30 cycloalkyl, C5-C12 aryl, C3-C12 heteroaryl.

[0035] Optionally, the substituted C1-C30 alkyl group is a C1-C30 alkyl group in which one or more methylene groups are substituted with -O- and / or -S- in a manner in which the O atoms and / or S atoms are not adjacent.

[0036] Preferably, R 1 -R 12 One of them has the structure represented by formula (I), and the other is hydrogen; L1 is selected from substituted or unsubstituted phenylene, substituted or unsubstituted biphenylene, substituted or unsubstituted terphenylene, substituted or unsubstituted naphthylene;

[0037] Preferably, R 1 -R 12 One of them has the structure represented by formula (II), and the other is hydrogen; L2 is selected from substituted or unsubstituted phenylene, substituted or unsubstituted biphenylene, substituted or unsubstituted terphenylene, substituted or unsubstituted naphthylene;

[0038] The substituted phenylene, substituted biphenylene, substituted terphenylene, and substituted naphthylene are selected from one or a combination of two of deuterium, halogen, cyano, C1-C6 alkyl, C3-C30 cycloalkyl, C5-C12 aryl, and C3-C12 heteroaryl;

[0039] Preferably, L1 is selected from phenylene, biphenylene, naphthylene; n is 0 or 1;

[0040] Preferably, L2 is selected from phenylene, biphenylene, and naphthylene.

[0041] Preferably, Ar 1 -Ar 2 Each is independently selected from substituted or unsubstituted A groups:

[0042] Wherein the A group is selected from one of the following groups:

[0043] phenyl, biphenyl, terphenyl, naphthyl, phenanthryl, anthracenyl, triphenylene, pyrenyl, phenylnaphthyl, naphthylphenyl, pyridyl, pyridyl, dibenzofuranyl, dibenzothiophenyl, benzonaphthofuranyl, dinaphthothiophenyl, dinaphthofuranyl, dinaphthothiophenyl, dibenzofuranylphenyl, dibenzothiophenylphenyl, phenyldibenzocarbazolyl, phenylbenzocarbazolyl, phenylcarbazolyl, dibenzocarbazolylphenyl, dimethylfluorenyl, benzodimethylfluorenyl, diphenylfluorenyl, spirobifluorenyl, and dimethylfluorenylphenyl;

[0044] The substituent of the substituted A group is selected from one or a combination of two of hydrogen, C1-C6 alkyl, C3-C30 cycloalkyl, C5-C12 aryl, and C3-C12 heteroaryl.

[0045] Preferably, Ar 1-Ar 2 Each is independently selected from phenyl, biphenyl, dibenzofuranyl, dibenzothiophenyl, benzonaphthofuranyl, dimethylfluorenyl, diphenylfluorenyl, and phenyldibenzocarbazolyl.

[0046] Preferably, formula (II) is selected from one of the following structures c-1, c-2, c-3, c-4, c-5, c-6 and c-7:

[0047]

[0048] Among them, R T1 -R T8 are each independently selected from hydrogen, deuterium, tritium, and substituted or unsubstituted D groups,

[0049] Wherein the D group is selected from one of the following groups:

[0050] methyl, ethyl, tert-butyl, adamantyl, phenyl, biphenyl, terphenyl, naphthyl, phenanthryl, anthracenyl, triphenylene, phenylnaphthyl, naphthylphenyl, pyridyl, bipyridyl, dibenzofuranyl, dibenzothiophenyl, benzonaphthofuranyl, benzonaphthothiophenyl, dinaphthofuranyl, dinaphthothiophenyl, dibenzofuranylphenyl, dibenzothiophenylphenyl, dimethylfluorenyl, benzodimethylfluorenyl, diphenylfluorenyl, spirobifluorenyl, and dimethylfluorenylphenyl;

[0051] The substituent of the substituted D group is selected from one or a combination of two of hydrogen, deuterium, halogen, cyano, C1-C6 alkyl, C3-C30 cycloalkyl, C5-C12 aryl, and C3-C12 heteroaryl.

[0052] Preferably, R 1 -R 12 One of them has the structure of formula c-4, and the other is hydrogen; wherein R T1 , R T2 , R T7 , R T8 All are hydrogen.

[0053] Preferably, R 13 , R 14 Each is independently selected from hydrogen, deuterium, and C1-C6 alkyl.

[0054] Preferably, R 13 , R 14 Each is independently selected from hydrogen, deuterium, methyl, ethyl, phenyl, naphthyl, and biphenyl.

[0055] Preferably, the formula (1) is selected from one of the following structures:

[0056]

[0057] Preferably, in the first host material, the compound represented by formula (1) has any of the following structures:

[0058]

[0059]

[0060]

[0061]

[0062]

[0063]

[0064]

[0065]

[0066]

[0067]

[0068] Where D stands for deuterium.

[0069] Preferably, the formula (2) is selected from the following structures:

[0070]

[0071] X 1 To X 6 are each independently selected from CR or N, and X 1 To X 4 At least one of represents N;

[0072] R is independently selected from hydrogen, substituted or unsubstituted C6-C30 aryl, substituted or unsubstituted C2-C30 alkenyl, substituted or unsubstituted C1-C30 alkyl; or R exists independently or two adjacent Rs are connected to form a ring C, which is a substituted or unsubstituted C6-C30 aromatic ring, a substituted or unsubstituted C3-C30 heteroaromatic ring; the ring C is a monocyclic or polycyclic ring;

[0073] Among them, L 1 ,Ar 3 and d is as defined above;

[0074] The substituents of the substituted C6-C30 aryl, substituted C2-C30 alkenyl, substituted C1-C30 alkyl, substituted C6-C30 aromatic ring, substituted C3-C30 heteroaromatic ring are selected from tritium, halogen, cyano, carboxyl, nitro, hydroxyl, C1-C30 alkyl, halogenated C1-C30 alkyl, C2-C30 alkenyl, C2-C30 alkynyl, C1-C30 alkoxy, C1-C30 alkylthio, C3-C30 cycloalkyl, C3-C30 cycloalkenyl, 3- to 7-membered heterocycloalkyl, C6-C30 aryloxy, C6-C30 arylthio, 5- to 30-membered heteroaryl, C6-C30 aryl, tri(C1-C30)alkylsilyl, tri(C6-C30)arylsilyl, di(C The invention also includes a (C1-C30)alkyl(C6-C30)arylsilyl group, a (C1-C30)alkyldi(C6-C30)arylsilyl group, an amino group, a mono- or di-(C1-C30)alkylamino group, a mono- or di-(C6-C30)arylamino group, a (C1-C30)alkyl(C6-C30)arylamino group, a (C1-C30)alkylcarbonyl group, a (C1-C30)alkoxycarbonyl group, a (C6-C30)arylcarbonyl group, a di(C6-C30)arylborylcarbonyl group, a di(C1-C30)alkylborylcarbonyl group, a (C1-C30)alkyl(C6-C30)arylborylcarbonyl group, a (C6-C30)aryl(C1-C30)alkyl(C6-C30)arylborylcarbonyl group, a (C6-C30)aryl(C1-C30)alkylgroup, and a (C1-C30)alkyl(C6-C30)aryl group.

[0075] Preferably, the formula (2) is selected from one of the following structures:

[0076]

[0077] Among them, X1 ’ -X 12 ’ Each is independently selected from N or CR', and R' is selected from hydrogen or deuterium;

[0078] L' is selected from a connecting bond, a substituted or unsubstituted C6-C30 arylene group, and a substituted or unsubstituted C3-C30 heteroarylene group;

[0079] R 16 , R 17 Each is independently selected from a substituted or unsubstituted C6-C30 aryl group, a substituted or unsubstituted C3-C30 heteroaryl group;

[0080] The substituents in the substituted C6-C30 arylene group, substituted C3-C30 heteroarylene group, substituted C6-C30 aryl group and substituted C3-C30 heteroaryl group are selected from one or a combination of two of deuterium, halogen, cyano, C1-C6 alkyl group, C3-C30 cycloalkyl group, C6-C30 aryl group and C3-C30 heteroaryl group.

[0081] Preferably, L' is selected from a linking bond, a substituted or unsubstituted C6-C12 arylene group, a substituted or unsubstituted C3-C12 heteroarylene group;

[0082] R 16 , R 17 are each independently selected from substituted or unsubstituted E groups,

[0083] The E group is selected from one of the following groups: phenyl, naphthyl, anthracenyl, biphenyl, terphenyl, phenanthryl, triphenylene, fluorenyl, dimethylfluorenyl, spirobifluorenyl, fluoranthenyl, diphenylfluorenyl, benzodimethylfluorenyl, benzodiphenylfluorenyl, benzospirobifluorenyl, dibenzofuranyl, dibenzothiophenyl, carbazolyl, phenylcarbazolyl, dipyridyl, pyrimidinyl, triazine;

[0084] The substituents of the substituted C6-C12 arylene group, the substituted C3-C12 heteroarylene group, and the substituted E group are selected from one or a combination of two of hydrogen, deuterium, halogen, cyano, C1-C6 alkyl, C3-C30 cycloalkyl, C5-C12 aryl, and C3-C12 heteroaryl.

[0085] Preferably, L' is selected from a linking bond;

[0086] R 16 , R 17 Each is independently selected from phenyl, naphthyl, anthracenyl, biphenyl, dimethylfluorenyl, spirobifluorenyl, diphenylfluorenyl, dibenzofuranyl, and dibenzothiophenyl.

[0087] The connecting bond in the present invention may be a single bond.

[0088]

[0089] As can be understood from Formula 2-3, in the present invention, L' can be connected to Ring H or Ring I, and R can be connected to Ring G or Ring K;

[0090] Formula 2-4 and Formula 2-5 are similar to the above explanations.

[0091] Preferably, X1 ’ -X 12 ’ 0-2 of them are selected from N, the others are independently selected from CR', and R' is selected from hydrogen or deuterium.

[0092] Preferably, X1 ’ -X 12 ’ Each is independently selected from CR', R' is selected from hydrogen or deuterium;

[0093] or, X1 ’ -X 12 ’ Medium X2 ’ is selected from N, the others are each independently selected from CR', R' is selected from hydrogen or deuterium;

[0094] or, X1 ’ -X 12 ’ Medium X5 ’ is selected from N, the others are each independently selected from CR', R' is selected from hydrogen or deuterium;

[0095] or, X1 ’ -X 12 ’ Medium X6 ’ is selected from N, the others are each independently selected from CR', R' is selected from hydrogen or deuterium;

[0096] or, X1 ’ -X 12 ’ Medium X7 ’ is selected from N, the others are each independently selected from CR', R' is selected from hydrogen or deuterium;

[0097] or, X1 ’ -X 12 ’ Medium X8 ’ is selected from N, the others are each independently selected from CR', R' is selected from hydrogen or deuterium;

[0098] or, X1 ’ -X 12 ’ Medium X9 ’ is selected from N, the others are each independently selected from CR', R' is selected from hydrogen or deuterium;

[0099] or, X1 ’ -X 12 ’ Medium X5 ’ 、X7 ’ is selected from N, the others are independently selected from CR', and R' is selected from hydrogen or deuterium. Preferably, in the second host material, the compound represented by formula (2) has any of the following structures:

[0100]

[0101]

[0102]

[0103]

[0104]

[0105]

[0106]

[0107]

[0108] Preferably, the mass ratio of the compound represented by formula (1) to the compound represented by formula (2) is 1:9-9:1;

[0109] Preferably, the mass ratio of the compound represented by formula (1) to the compound represented by formula (2) is 2:8-8:2;

[0110] More preferably, the mass ratio of the compound represented by formula (1) to the compound represented by formula (2) is 3:7-7:3;

[0111] More preferably, the mass ratio of the compound represented by formula (1) to the compound represented by formula (2) is 4:6-6:4.

[0112] The present invention provides the use of the above-mentioned organic electroluminescent material in the preparation of optical devices.

[0113] Preferably, the optical device comprises any one of an organic electroluminescent device, an organic field effect transistor, an organic thin film transistor, an organic light emitting transistor, an organic integrated circuit, an organic solar cell, an organic field quenching device, a light emitting electrochemical cell, an organic laser diode or an organic photoreceptor.

[0114] The present invention provides an organic electroluminescent device, which comprises an anode and a cathode, and an organic layer arranged between the anode and the cathode, wherein the organic layer comprises the organic electroluminescent material as described above, and preferably, the light-emitting layer in the organic layer comprises the organic electroluminescent material as described above.

[0115] Preferably, the organic layer comprises a hole injection layer, a hole transport layer, an electron blocking layer, a light emitting layer, a hole blocking layer, an electron transport layer and an electron injection layer stacked in sequence from the anode side to the cathode side;

[0116] Preferably, the material of the light-emitting layer comprises a host material and a guest material, and the host material comprises the organic electroluminescent material as described above.

[0117] Preferably, the guest material comprises a phosphorescent dopant, and the phosphorescent dopant comprises a complex containing a transition metal.

[0118] The present invention also provides an organic electroluminescent device, which includes the organic electroluminescent device described above.

[0119] In the present invention, the synthesis path of the first host material includes the following method:

[0120] 1. When n = 0,

[0121] (1) Compound Nn-A reacts with compound Nn-B to obtain intermediate Nn-1:

[0122]

[0123] Wherein Hal represents halogen;

[0124] (2) Compound Nn-1 reacts with diarylamine Nn-C to obtain compound Nn:

[0125]

[0126] 2. When n is not 0 and L1 is not a connecting key,

[0127] (1) Compound Nn-1 reacts with bipyralidone to obtain intermediate Nn-2:

[0128]

[0129] Bpin is pinacol borate.

[0130] (2) Compound Nn-2 is subjected to coupling reaction with aromatic amine Nn-DSuzuki to obtain compound Nn:

[0131]

[0132] Hal 1 Represents halogen.

[0133] 3. When L2 is not a connection key,

[0134] (1) Compound Nn-1 reacts with bipyralidone to obtain intermediate Nn-2:

[0135]

[0136] (2) Compound Nn-2 reacts with Nn-D to obtain compound Nn:

[0137]

[0138] Hal 1 Represents halogen.

[0139] Beneficial effects of the present invention:

[0140] The organic electroluminescent material of the present invention comprises a first host material comprising a compound represented by formula (I), and a second host material comprising a compound represented by formula (2). The compound represented by formula (I) and the compound represented by formula (2) cooperate with each other, which is beneficial for matching HOMO and LUMO energy levels with adjacent energy levels, so that the organic electroluminescent compound obtains higher stability and more balanced carrier mobility, thereby making the organic electroluminescent device comprising the material have a better lifespan, lower driving voltage and higher efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0141] In order to more clearly illustrate the specific implementation methods of the present invention or the technical solutions in the prior art, the drawings required for use in the specific implementation methods or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some implementation methods of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0142] Figure 1 A structural diagram of an organic electroluminescent device in an embodiment of the device of the present invention;

[0143] Among them, 1-substrate; 2-anode; 3-hole injection layer; 4-hole transport layer; 5-light-emitting layer; 6-electron transport layer; 7-electron injection layer; 8-cathode. DETAILED DESCRIPTION

[0144] The following examples are provided for a better understanding of the present invention, but are not intended to limit the best mode of implementation, nor to limit the content and protection scope of the present invention. Any product identical or similar to the present invention obtained by anyone under the inspiration of the present invention or by combining the features of the present invention with other prior arts shall fall within the protection scope of the present invention.

[0145] If no specific experimental steps or conditions are specified in the examples, the conventional experimental steps or conditions described in the literature in the field can be used. If no manufacturer is specified for the reagents or instruments used, they are all conventional reagent products that can be purchased commercially.

[0146] Example 1

[0147] This embodiment provides a method for preparing a compound having an N-1 structure in an organic electroluminescent material, comprising the following steps:

[0148]

[0149] Synthesis of N1-1: Take a 1-liter four-mouth round-bottom flask and put in a stirrer and a reflux tube. After drying, fill with nitrogen. Take 10g N1-A (48.4mmol, CAS: 781-43-1) and add it to the flask. Dissolve it with 168mL of anhydrous dichloromethane (DCM) and heat it to reflux. Dissolve 20.9g N1-B (96.9mmol, CAS: 20776-48-1) in 140mL of anhydrous tetrahydrofuran (THF) to prepare N1-B / THF solution, and dissolve 14.2g of isoamyl nitrite in 126mL of anhydrous DCE to prepare isoamyl nitrite / DCE solution. Add N1-B / THF and isoamyl nitrite / DCE solution dropwise at the same time, and keep the content of isoamyl nitrite in the system always greater than the content of N1-B in the system. The addition time is controlled to be about 4h. After the addition was completed, the mixture was stirred and reacted for 12 hours under reflux. The target product, compound N1-1 (7 g, yield: 42%), was obtained by purification by column chromatography.

[0150] Synthesis of N-1: 7 g of the above-obtained compound N1-1 (19.33 mmol), 3.43 g of compound N1-C (20.3 mmol, CAS: 122-39-4), 354 mg of Pd2(dba)3 (0.386 mmol) (dba is distyryl acetone), 396 mg of S-Phos (0.966 mmol) (S-Phos is 2-dicyclohexylphosphine-2', 6'-dimethoxybiphenyl), 7.4 g of t-BuONa (38.6 mmol) were added to a 500 mL four-necked flask, 70 mL of toluene was added thereto, and the mixture was stirred at 110° C. for 5 hours. After the reaction was completed, the obtained solid was purified by column chromatography to obtain compound N-1 (6 g, yield: 70%).

[0151] Elemental analysis: C 34 H 27 N theoretical value: C, 90.83; H, 6.05; N, 3.12; found value: C, 90.80; H, 6.06; N, 3.14; HRMS (ESI) m / z [M+H] +: theoretical value: 449.21; found value: 450.59.

[0152] Example 2

[0153] This embodiment provides a method for preparing a compound having an N-37 structure in an organic electroluminescent material, comprising the following steps:

[0154]

[0155] Synthesis of N37-C: 7 g of compound N37-A (21 mmol, CAS: 1268519-74-9), 5.45 g of compound N37-B (20 mmol, CAS: 28320-31-2), 354 mg of Pd2(dba)3 (0.386 mmol), 396 mg of S-Phos (0.966 mmol), 7.4 g of t-BuONa (386.44 mmol) were added to a 500 mL four-necked flask, 70 mL of toluene was added thereto, and the mixture was stirred at 110° C. for 5 hours. After the reaction was completed, the solid was purified by column chromatography to obtain compound N37-C (9 g, yield: 81.8%).

[0156] Synthesis of N-37: 9 g of the compound N37-C (17 mmol) obtained above, 6.17 g of the compound N1-1 (17.1 mmol), 269 mg of Pd2(dba)3 (0.29 mmol), 301 mg of S-Phos (0.734 mmol), and 2.82 g of t-BuONa (29.36 mmol) were added to a 500 mL four-necked flask, 90 mL of toluene was added thereto, and the mixture was stirred at 110° C. for 5 hours. After the reaction was completed, the solid obtained was purified by column chromatography to obtain compound N-37 (10 g, yield: 72%).

[0157] Elemental analysis: C 62 H 47 N theoretical value: C, 92.38; H, 5.88; N, 1.74; found value: C, 92.35; H, 5.87; N, 1.78; HRMS (ESI) m / z [M+H]+: theoretical value: 805.37; found value: 806.15.

[0158] Example 3

[0159] This embodiment provides a method for preparing a compound having an N-71 structure in an organic electroluminescent material, comprising the following steps:

[0160]

[0161] Synthesis of N71-1: Take a 1-liter four-mouth round-bottom flask and put in a stirrer and a reflux tube. After drying, fill with nitrogen. Take 10gN1-A (48.4mmol, CAS: 781-43-1) and add it to the flask. Dissolve it with 168mL of anhydrous DCM and heat it to reflux. Dissolve 20.9g N71-B (96.9mmol, CAS: 5794-88-7) in 140mL of anhydrous THF to prepare N71-B / THF solution, and dissolve 14.2g of isoamyl nitrite in 126mL of anhydrous DCE to prepare isoamyl nitrite / DCE solution. Add N71-B / THF and isoamyl nitrite / DCE solution dropwise at the same time, and keep the content of isoamyl nitrite in the system always greater than the content of N71-B in the system. The addition time is controlled to be about 4h. After the addition is completed, stir the reaction under reflux for 12h. Purification by column chromatography gave the target product, compound N71-1 (7 g, yield: 42%).

[0162] Synthesis of N-71: 7 g of the above-obtained compound N71-1 (19.33 mmol), 3.43 g of compound N1-C (20.3 mmol, CAS: 122-39-4), 354 mg of Pd2(dba)3 (0.386 mmol), 396 mg of S-Phos (0.966 mmol), and 7.4 g of t-BuONa (38.6 mmol) were added to a 500 mL four-necked flask, 70 mL of toluene was added thereto, and the mixture was stirred at 110° C. for 5 hours. After the reaction was completed, the obtained solid was purified by column chromatography to obtain compound N-71 (6 g, yield: 70%).

[0163] Elemental analysis: C 34 H 27 N theoretical value: C, 90.83; H, 6.05; N, 3.12; found value: C, 90.81; H, 6.05; N, 3.14; HRMS (ESI) m / z [M+H]+: theoretical value: 449.21; found value: 449.07.

[0164] Example 4

[0165] This embodiment provides a method for preparing a compound having an N-141 structure in an organic electroluminescent material, comprising the following steps:

[0166]

[0167] Synthesis of N141-b: Take a 1-liter four-necked round-bottom flask and put in a stirrer and a reflux tube. After drying, fill it with nitrogen. Take 10g N141-a (48.07mmol, CAS: 84-65-1) and add it to the flask. Cool it to -70~-80℃, and drop 144mL ethyl lithium (144.23mmol, 1.0mol / L in Diethyl ether) into the system. After 2h of dropwise addition, pour the system into 1L ammonium chloride aqueous solution, extract, and purify it by column chromatography to obtain the target product, compound N141-b (10g, yield: 78%)

[0168] Synthesis of N141-A: Add 10g N141-b (37.3mmol) obtained above into a 250mL four-necked round-bottom flask, fill with nitrogen after drying, cool the system to 0°C, and simultaneously add 15.6g triethylsilane (134.32mmol, CAS: 617-86-7) and 42.8g boron trifluoride ether solution (141.79mmol, 47%, CAS: 109-63-7) dropwise. Add after 2h, transfer to room temperature and stir for 2h, after the reaction is complete, add 100mL water to quench the reaction, extract, and purify by column chromatography to obtain the target product, compound N141-A (6g, yield: 69%)

[0169] Synthesis of N141-1: Take a 1-liter four-mouth round-bottom flask and put it in a stirrer and a reflux tube. After drying, fill it with nitrogen. Take 6g N141-A (25.6mmol) and add it to the flask. Dissolve it with 100mL of anhydrous DCM and heat it to reflux. Dissolve 11.08g N1-B (51.28mmol, CAS: 20776-48-1) in 84mL of anhydrous THF to prepare N1-B / THF solution, and dissolve 7.5g of isoamyl nitrite (64.1mmol, CAS: 110-46-3) in 76mL of anhydrous DCE to prepare isoamyl nitrite / DCE solution. Add N1-B / THF and isoamyl nitrite / DCE solution dropwise at the same time, and keep the content of isoamyl nitrite in the system always greater than the content of N1-B in the system. The addition time is controlled to be about 4h. After the addition is completed, stir the reaction under reflux for 12h. Purification by column chromatography gave the target product, compound N141-1 (6 g, yield: 60%).

[0170] Synthesis of N-141: 6 g of compound N141-1 (15.42 mmol), 3.98 g of compound N141-C (16.24 mmol, CAS: 32228-99-2), 282 mg of Pd2(dba)3 (0.308 mmol), 316 mg of S-Phos (0.77 mmol), and 2.96 g of t-BuONa (30.8 mmol) were added to a 250 mL four-necked flask, 60 mL of toluene was added thereto, and the mixture was stirred at 110° C. for 3 hours. After the reaction was completed, the solid was purified by column chromatography to obtain compound N-141 (6 g, yield: 71%).

[0171] Elemental analysis: C 42 H 35 N theoretical value: C, 91.10; H, 6.37; N, 2.53; found value: C, 91.05; H, 6.39; N, 2.56; HRMS (ESI) m / z [M+H] +: theoretical value: 553.28; found value: 554.17.

[0172] Example 5

[0173] This embodiment provides a method for preparing a compound having an N-178 structure in an organic electroluminescent material, comprising the following steps:

[0174]

[0175] Synthesis of N178-D: Take a 250mL four-necked round-bottom flask and put a stirrer and a reflux tube on it, fill it with nitrogen after drying, take 10g N178-a (37.5mmol, CAS: 194-59-2) and add it to the flask, 6.76g compound N178-b (39.33mmol, CAS: 106-40-1), 685mg Pd2(dba)3 (0.75mmol), 614mg S-Phos (1.50mmol), 7.34g t-BuONa (74.9mmol) and add it to a 250mL four-necked flask, measure 100mL toluene and add it thereto, and stir the mixture at 110°C for 4 hours. After the reaction is completed, the solid obtained is purified by column chromatography to obtain compound N178-D (12g, yield: 76%).

[0176]

[0177] Synthesis of N178-2: To a 250mL three-necked flask equipped with a thermometer and a magnetic stirrer, 7g of compound N141-1 (19.4mmol), 5.9g of bis-pinacol borate (23.3mmol, CAS: 73183-34-3), 3.8g of potassium acetate (38.8mmol) and 282mg of Pd(dppf)Cl2 (0.39mmol) were added, and 70mL of 1,4-dioxane was added. Under nitrogen protection, the temperature was raised to 110°C and the reaction was reacted for 4h. 100mL of toluene was added to the reaction solution, and 100mL of water was used for extraction and separation. The organic phase was mixed and passed through a column to obtain the intermediate N178-2 (6g, yield: 76%).

[0178]

[0179] Synthesis of N-178: 6.2g of compound N178-D (14.69mmol), 6g of compound N178-2 (14.69mmol), 4.05g of K2CO3 (29.38mmol), 339mg of Pd(PPh3)4 (0.294mmol) were added to a 250mL three-necked flask equipped with a thermometer and magnetic stirring, and 45mL of toluene, 20mL of ethanol and 20mL of water were added. Under nitrogen protection, the temperature was raised to 85°C for 4h. After the reaction was completed, the product N-178 (6g, yield: 66%) was obtained by purification by column chromatography and drying.

[0180] Elemental analysis: C 50 H 37 N theoretical value: C, 92.13; H, 5.72; N, 2.15; found value: C, 92.09; H, 5.73; N, 2.18; HRMS (ESI) m / z [M+H] +: theoretical value: 651.29; found value: 652.66.

[0181] Example 6

[0182] This embodiment provides a method for preparing a compound having an N-227 structure in an organic electroluminescent material, comprising the following steps:

[0183]

[0184] Synthesis of N227-b: Take a 250mL four-necked round-bottom flask and put it in a stirring bar and a reflux tube. After drying, fill it with nitrogen. At room temperature, take 10g N227-a (55.48mmol, CAS: 613-31-0) and add it to the flask. Dissolve it with 20mL deuterated dimethyl sulfoxide ((99.9% atom D, CAS: 2206-27-1), add 4.48g potassium hydride (0.1122mol), and the reaction mixture turns dark red. After stirring and reacting for 2h, 16mL of heavy water (99.9% atom D, CAS: 7789-20-0) is added to the system, and a white precipitate appears immediately. Stir the reaction for another 1h, filter to obtain 8g of the product, rinse with water, and then recrystallize and purify it with ethanol to obtain the target product N227-b (7g, yield: 73%).

[0185] Synthesis of N227-A: 7 g of N227-b (38.04 mmol) obtained above was added to a 250 mL four-necked round-bottom flask, 37 g of 3,4,5,6-tetrachloro-1,2-benzoquinone (0.152 mol, CAS: 2435-53-2) was added, 70 mL of 1,4-dioxane was added to the system, and heated to 30°C for 48 h. After the reaction was completed, the target product, compound N227-A (6 g, yield: 88%) was obtained by purification by column chromatography.

[0186] Synthesis of N227-1: Take a 1-liter four-mouth round-bottom flask and put it in a stirrer and a reflux tube. After drying, fill it with nitrogen. Take 6g N227-A (33.3mmol) and add it to the flask. Dissolve it with 100mL of anhydrous DCM and heat it to reflux. Dissolve 14.4g N1-B (66.6mmol, CAS: 20776-48-1) in 84mL of anhydrous THF to prepare N1-B / THF solution, and dissolve 9.75g of isoamyl nitrite (83.3mmol, CAS: 110-46-3) in 76mL of anhydrous DCE to prepare isoamyl nitrite / DCE solution. Add N1-B / THF and isoamyl nitrite / DCE solution dropwise at the same time, and keep the content of isoamyl nitrite in the system always greater than the content of N1-B in the system. The dropping time is controlled at about 4h. After the dropwise addition is completed, stir the reaction under reflux for 12h. Purification by column chromatography gave the target product, compound N227-1 (7 g, yield: 63%).

[0187] Synthesis of N-227: 7 g of the compound N227-1 (20.9 mmol), 3.7 g of the compound N1-C (21.9 mmol, CAS: 122-39-4), 382 mg of Pd2(dba)3 (0.418 mmol), 428 mg of S-Phos (1.04 mmol), and 4.01 g of t-BuONa (41.79 mmol) were added to a 250 mL four-necked flask, 70 mL of toluene was added thereto, and the mixture was stirred at 110° C. for 5 hours. After the reaction was completed, the solid was purified by column chromatography to obtain compound N-227 (6.6 g, yield: 75%).

[0188] Elemental analysis: C 32 H 21 D2N theoretical value: C, 90.74; H, 5.95; N, 3.31; found value: C, 90.71; H, 5.96; N, 3.33; HRMS (ESI) m / z [M+H]+: theoretical value: 423.20; found value: 424.54.

[0189] Example 7

[0190] This embodiment provides a method for preparing a compound having an N-277 structure in an organic electroluminescent material, comprising the following steps:

[0191]

[0192] Synthesis of N277-c: Take a 250mL four-necked round-bottom flask and put a stirring rod and a reflux tube on it, fill it with nitrogen after drying, take 10g N277-a (37.5mmol, CAS: 194-59-2) and add it to the flask, 6.76g compound N277-b (39.33mmol, CAS: 106-40-1), 685mg Pd2(dba)3 (0.75mmol), 614mg S-Phos (1.50mmol), 7.34g t-BuONa (74.9mmol) and add it to a 250mL four-necked flask, measure 100mL toluene and add it, and stir the mixture at 110°C for 4 hours. After the reaction is completed, the solid obtained is purified by column chromatography to obtain compound N277-c (12g, yield: 76%).

[0193] Synthesis of N277-C: 12 g of the compound N277-c (28.44 mmol) obtained above, 2.78 g of aniline (29.86 mmol, CAS: 62-53-3), 520 mg of Pd2(dba)3 (0.569 mmol), 466 mg of S-Phos (11.37 mmol), 5.57 gt-BuONa (56.87 mmol) were added to a 250 mL four-necked flask, 120 mL of toluene was added thereto, and the mixture was stirred at 110° C. for 3 hours. After the reaction was completed, the solid obtained was purified by column chromatography to obtain compound N277-C (9 g, yield: 75%).

[0194] Synthesis of N-277: Take a 250mL four-necked round-bottom flask and put in a stirrer and a reflux tube, dry and fill with nitrogen, take 9g N277-C (20.74mmol) and add it to the flask, 7.84g compound N227-1 (21.77mmol), 379mg Pd2(dba)3 (0.415mmol), 340g S-Phos (0.829mmol), 4.06g t-BuONa (41.5mmol) and add it to a 250mL four-necked flask, measure 90mL of xylene and add it, and stir the mixture at 140°C for 4 hours. After the reaction is completed, cool and filter to obtain the target product, and then slurry with ethanol to obtain compound N-277 (11g, yield: 74%).

[0195] Elemental analysis: C 54 H 38 N2 theoretical value: C, 90.72; H, 5.36; N, 3.92; found value: C, 90.69; H, 5.35; N, 3.96; HRMS (ESI) m / z [M+H]+: theoretical value: 714.30; found value: 715.22.

[0196] Example 8

[0197] This embodiment provides a method for preparing a compound having an N-278 structure in an organic electroluminescent material, comprising the following steps:

[0198]

[0199] Synthesis of N278-b: Take a 250mL four-necked round-bottom flask and put it in a stirring bar and a reflux tube. After drying, fill it with nitrogen. At room temperature, take 10g N278-a (55.48mmol, CAS: 613-31-0) and add it to the flask. Dissolve it with 20mL deuterated dimethyl sulfoxide ((99.9% atom D, CAS: 2206-27-1), add 4.48g potassium hydride (0.1122mol), and the reaction mixture turns dark red. After stirring and reacting for 2h, 16mL of heavy water (99.9% atom D, CAS: 7789-20-0) is added to the system, and a white precipitate appears immediately. Stir the reaction for another 1h, filter to obtain 8g of the product, rinse with water, and then recrystallize and purify it with ethanol to obtain the target product N278-b (7g, yield: 73%).

[0200] Synthesis of N278-A: 7 g of N278-b (38.04 mmol) obtained above was added to a 250 mL four-necked round-bottom flask, 37 g of 3,4,5,6-tetrachloro-1,2-benzoquinone (0.152 mol, CAS: 2435-53-2) was added, 70 mL of 1,4-dioxane was added to the system, and the mixture was heated to 30°C and reacted for 48 hours. After the reaction was completed, the target product, compound N278-A (6 g, yield: 88%) was obtained by purification by column chromatography.

[0201] Synthesis of N278-1: Take 1 liter of four-mouth round-bottom flask and put in a stirrer and a reflux tube, fill with nitrogen after drying, take 6g N278-A (33.3mmol) and add it to the flask, dissolve it with 100mL of anhydrous DCM, and heat it to reflux. 14.4g N71-B (66.6mmol, CAS: 20776-48-1) is dissolved in 84mL of anhydrous THF to prepare N71-B / THF solution, 9.75g isoamyl nitrite (83.3mmol, CAS: 110-46-3) is dissolved in 76mL of anhydrous DCE to prepare isoamyl nitrite / DCE solution. N71-B / THF and isoamyl nitrite / DCE solution are added dropwise at the same time, and the content of isoamyl nitrite in the system is always greater than the content of N71-B in the system. The addition time is controlled to be about 4h. After the addition was completed, the mixture was stirred and reacted for 12 hours under reflux. The target product, compound N278-1 (7.5 g, yield: 68%), was obtained by purification by column chromatography.

[0202] Synthesis of N-278: 7.5 g of compound N278-1 (22.38 mmol), 3.97 g of compound N1-C (23.5 mmol, CAS: 122-39-4), 410 mg of Pd2(dba)3 (0.447 mmol), 459 mg of S-Phos (1.12 mmol), and 4.3 g of t-BuONa (44.78 mmol) were added to a 250 mL four-necked flask, 75 mL of xylene was added thereto, and the mixture was stirred at 110° C. for 5 hours. After the reaction was completed, the solid was purified by column chromatography to obtain compound N-278 (8 g, yield: 84%).

[0203] Elemental analysis: C 32 H 21 D2N theoretical value: C, 90.74; H, 5.95; N, 3.31; found value: C, 90.72; H, 5.95; N, 3.33; HRMS (ESI) m / z [M+H]+: theoretical value: 423.20; found value: 424.16.

[0204] Example 9

[0205] This embodiment provides a method for preparing a compound having an N-308 structure in an organic electroluminescent material, comprising the following steps:

[0206]

[0207] Synthesis of N308-2: To a 250mL three-necked flask equipped with a thermometer and a magnetic stirrer, 7g of compound N71-1 (19.4mmol), 5.9g of bispinacol borate (23.3mmol, CAS: 73183-34-3), 3.8g of potassium acetate (38.8mmol) and 282mg of Pd(dppf)Cl2 (0.39mmol) were added, and 70mL of 1,4-dioxane was added. Under nitrogen protection, the temperature was raised to 110°C and the reaction was reacted for 4h. 100mL of toluene was added to the reaction solution, and 100mL of water was used for extraction and separation. The organic phase was mixed and passed through a column to obtain the intermediate N308-2 (6g, yield: 76%).

[0208] Synthesis of N-308: Add 6g of compound N308-2 (14.7mmol), 5.0g of compound N308-D (15.4mmol, CAS: 36809-26-4), 4.06g of K2CO3 (29.4mmol), and 340mg of Pd(PPh3)4 (0.294mmol) obtained above into a 250mL four-necked flask, add 50mL of toluene, 20mL of ethanol and 20mL of water, and heat to 85℃ for 6h under nitrogen protection. After the reaction is completed, 50mL of water and 50mL of toluene are added in turn, and the organic phase is mixed and passed through a column to obtain the final product N-308 (5.6g, yield: 73%).

[0209] Elemental analysis: C 40 H 31 N theoretical value: C, 91.39; H, 5.94; N, 2.66; found value: C, 91.36; H, 5.93; N, 2.71; HRMS (ESI) m / z [M+H] +: theoretical value: 525.25; found value: 525.11.

[0210] Example 10

[0211] This embodiment provides a method for preparing a compound having an N-315 structure in an organic electroluminescent material, comprising the following steps:

[0212]

[0213] Synthesis of N315-D: 8 g of compound N315-a (24.6 mmol, CAS: 101606-18-2), 6.9 g of compound N315-b (29.6 mmol, CAS: 2052-07-5), 214 mg of Pd2(dba)3 (0.233 mmol), 192 mg of S-Phos (0.48 mmol), and 2.3 g of t-BuONa (23.4 mmol) were added to a 250 mL four-necked flask, 80 mL of toluene was added thereto, and the mixture was stirred at 110° C. for 3 hours. After the reaction was completed, the obtained solid was purified by column chromatography to obtain compound N315-D (9.5 g, yield: 82%).

[0214] Synthesis of N-315: 9g of the above-obtained compound N315-D (18.9mmol), 8.5g of the compound N308-2 (20.8mmol), 4.06g of K2CO3 (29.4mmol), and 340mg of Pd(PPh3)4 (0.294mmol) were added to a 250mL four-necked flask, and 50mL of toluene, 20mL of ethanol, and 20mL of water were added. Under nitrogen protection, the temperature was raised to 85°C for 4h. After the reaction was completed, the solid was purified by column chromatography to obtain compound N-315 (9g, yield: 70%).

[0215] Elemental analysis: C 52 H 39 N theoretical value: C, 92.13; H, 5.80; N, 2.07; found value: C, 92.10; H, 5.79; N, 2.11; HRMS (ESI) m / z [M+H] +: theoretical value: 677.31; found value: 678.23.

[0216] Embodiment 11

[0217] This embodiment provides a method for preparing a compound having an N-322 structure in an organic electroluminescent material, comprising the following steps:

[0218]

[0219] Synthesis of N322-D: Take a 250mL four-necked round-bottom flask and put a stirring bar and a reflux tube on it, fill it with nitrogen after drying, take 10g N322-a (35.0mmol, CAS: 13720-06-4) and add it to the flask, 9g compound N322-b (36.7mmol, CAS: 32228-99-2), 640mg Pd2(dba)3 (0.699mmol), 573mg S-Phos (1.40mmol), 6.85g t-BuONa (69.9mmol) and add it to a 250mL four-necked flask, measure 100mL toluene and add it, and stir the mixture at 110°C for 4 hours. After the reaction is completed, the solid obtained is purified by column chromatography to obtain compound N322-D (12g, yield: 76%).

[0220] Synthesis of N-322: 12g of compound N322-D (26.6mmol), 10.88g of compound N308-2 (26.67mmol), 7.36g of K2CO3 (53.3mmol), 616mg of Pd(PPh3)4 (0.533mmol) were added to a 250mL three-necked flask equipped with a thermometer and magnetic stirring, and 85mL of toluene, 35mL of ethanol and 35mL of water were added. Under nitrogen protection, the temperature was raised to 85°C for 4h. After the reaction was completed, the product N-322 (12g, yield: 70%) was obtained by purification by column chromatography and drying.

[0221] Elemental analysis: C 50 H 37 N theoretical value: C, 92.13; H, 5.72; N, 2.15; found value: C, 92.10; H, 5.73; N, 2.17; HRMS (ESI) m / z [M+H] +: theoretical value: 651.29; found value: 652.38.

[0222] Example 12

[0223] This embodiment provides a method for preparing a compound having an N-346 structure in an organic electroluminescent material, comprising the following steps:

[0224]

[0225] Synthesis of N366-1: In a 1000 ml three-necked flask, after drying and filling with nitrogen, add 22 g of N346-A (66.6 mmol, CAS: 1499-10-1) and 180 ml of 1,2-dichloroethane, and stir at 80°C to dissolve. Add 20 ml of isoamyl nitrite (150.2 mmol) and stir at 80°C for 5 minutes. Add 25 g (115.7 mmol) of anthranilic acid N346-B dissolved in diethylene glycol dimethyl ether (100 ml) dropwise and stir at 150°C for 3 hours. After cooling to room temperature, the obtained reaction mixture is purified by silica gel column chromatography. Then, it is reslurried by heating with chloroform to obtain 16.5 g of intermediate N346-1.

[0226]

[0227] Synthesis of N-346: In a 200ml three-necked flask, after drying, nitrogen was filled, and intermediate N346-16.5g (13.4mmol), carbazole 2.7g (16.1mmol), copper iodide 3.0g (15.8mmol), potassium carbonate 3.7g (26.8mmol) were added, and quinoline 100ml was added thereto, and stirred at 170°C for 30 hours. After cooling to room temperature, 100ml of dichloromethane and 50ml of water were added, and after stirring for 1 hour, the reaction solution was transferred to a 500mL separatory funnel and separated into an organic layer and an aqueous layer. The organic layer was washed twice with 200mL of water, and then the obtained organic layer was dehydrated with magnesium sulfate. Once the magnesium sulfate was filtered and separated, the solvent was removed by distillation under reduced pressure. The obtained reaction mixture was refined by silica gel column chromatography, and heated with ethyl acetate and re-slurried to obtain compound N-346 (4.6g) as a white solid.

[0228] Elemental analysis: C 44 H 29 N theoretical value: C, 92.44; H, 5.11; N, 2.45; found value: C, 92.40; H, 5.12; N, 2.48; HRMS (ESI) m / z [M+H] +: theoretical value: 571.23; found value: 572.39.

[0229] Embodiment 13-32

[0230] The preparation of Example 13-32 is similar to that of Example 1. Specifically, the raw materials used in Example 13-32 and the products obtained are shown in Table 1:

[0231]

[0232]

[0233]

[0234]

[0235] The product characterization data are shown in Table 2:

[0236] Table 2

[0237]

[0238]

[0239]

[0240] Embodiment 33

[0241] This embodiment provides a method for preparing a compound having an M-17 structure in an organic electroluminescent material, comprising the following steps:

[0242]

[0243] Synthesis of M-17: Take a 50 ml double-necked round-bottom flask and put in a stirrer and a reflux tube, dry it and fill it with nitrogen, add compound M17-A (14.1 mmol, CAS2095370-50-4), M17-B (18.3 mmol), tetrakis (triphenylphosphine) palladium (0.7 mmol), potassium carbonate (28.2 mmol), 42 ml of toluene, 10 ml of ethanol and 14 ml of distilled water, and stir the mixture at 140 ° C for 8 hours. After the reaction is completed, the mixture is added dropwise to methanol, and the solid is filtered. The solid is purified by column chromatography to obtain compound M-17 (5.8 g, yield: 75%).

[0244] Elemental analysis: C 39 H 23 Theoretical value of N3O: C, 85.23; H, 4.22; N, 7.65; O, 2.91; Found value: C, 85.21; H, 4.22; N, 7.66; HRMS (ESI) m / z (M+): Theoretical value: 549.18; Found value: 550.57.

[0245] Embodiment 34

[0246] This embodiment provides a method for preparing a compound having an M-281 structure in an organic electroluminescent material, comprising the following steps:

[0247]

[0248] Synthesis of intermediate M281-A

[0249] To a 250mL three-necked flask equipped with a thermometer and a magnetic stirrer, add intermediate M281-1 (20g) and 200mL of anhydrous tetrahydrofuran. Under nitrogen protection, cool to -78°C, control the temperature and add n-butyl lithium (1.6M 45.2mL) dropwise, stir for 1h, then control the temperature to -78°C and add triisopropyl borate (19.52g), transfer to room temperature and react for 12h, add hydrochloric acid solution (36% hydrochloric acid 6.5mL + 24mL water), add 50mL of ethyl acetate to the reaction solution, extract with 25mL of water, spin dry the organic phase and add 50mL of n-hexane, reflux and slurry for 1h, filter at room temperature and dry to obtain intermediate M281-2, 15g.

[0250] To a 250 mL three-necked flask equipped with a thermometer and magnetic stirring, add intermediate M281-2 (15 g), intermediate 3-bromopyridine-4-aldehyde (11.2 g), potassium carbonate (16.6 g) and tetrakistriphenylphosphine palladium (2.0 g), add toluene (80 mL), ethanol (35 mL) and water (35 mL). Under nitrogen protection, heat to 85 ° C and react for 6 hours. Add 50 mL of ethyl acetate to the reaction solution, extract with 25 mL of water, and separate the liquids. Mix the organic phase and pass it through a column to obtain intermediate M281-3, 15.2 g.

[0251] To a 250mL three-necked flask equipped with a thermometer and magnetic stirring, add intermediate M281-3 (15.2g), (methoxymethyl)triphenylphosphonium chloride (23.5g) and 75mL of anhydrous tetrahydrofuran. Under nitrogen protection, control the temperature to -5°C, add dropwise potassium tert-butoxide tetrahydrofuran solution (10.2g, 76mL), and react for 1h. Add 50mL of ethyl acetate to the reaction solution, extract with 25mL of water, separate the liquids, mix the organic phase and pass it through a column to obtain intermediate M281-4, 14g.

[0252] To a 250mL three-necked flask equipped with a thermometer and magnetic stirring, add intermediate M281-4 (14g) and 70mL of hexafluoroisopropanol. Under nitrogen protection, control the temperature to 0°C, add trifluoromethanesulfonic acid (11mL) dropwise, and react for 1h. Add 30mL of dichloromethane to the reaction solution, extract with 25mL of water, separate the liquids, mix the organic phase and pass it through a column to obtain intermediate M281-5, 11g.

[0253] To a 250 mL three-necked flask equipped with a thermometer and magnetic stirring, add intermediate M281-5 (11 g), diboronic acid pinacol ester (10.9 g), potassium acetate (8.8 g) and Pd(dppf)Cl2 (0.56 g), add 1,4-dioxane (110 mL) and under nitrogen protection, heat to 110 ° C and react for 4 h. Add 100 mL of toluene to the reaction solution, extract with 100 mL of water, and separate the liquids. Mix the organic phase and pass it through a column to obtain 11 g of intermediate M281-A.

[0254] Synthesis of Compound M-281

[0255]

[0256] To a 250mL three-necked flask equipped with a thermometer and magnetic stirring device, intermediate M281-A (11g), intermediate M281-B (10g), potassium carbonate (9.9g) and tetrakistriphenylphosphine palladium (1.2g) were added, and toluene (60mL), ethanol (20mL) and water (20mL) were added. Under nitrogen protection, the temperature was raised to 85°C and the reaction was reacted for 6h. Water and ethanol were added to the reaction solution at room temperature and filtered. After drying, the product M281, 12g (yield 86.7%) was obtained.

[0257] Elemental analysis: C32 H 20 N4 theoretical value: C, 83.46; H, 4.38; N, 12.17; found value: C, 83.44; H, 4.38; N, 12.18; HRMS (ESI) m / z (M+): theoretical value: 460.17; found value: 461.04.

[0258] Examples 35-51

[0259] The preparation of Examples 35-51 is similar to that of the above examples. Specifically, the raw materials used in Examples 35-51 and the products obtained are shown in the following table:

[0260] Table 3

[0261]

[0262]

[0263]

[0264]

[0265] The product characterization data are shown in Table 4:

[0266] Table 4

[0267]

[0268]

[0269] Device Embodiment

[0270] This embodiment provides an organic electroluminescent device, such as Figure 1 As shown, it includes an anode 2, a hole injection layer 3, a hole transport layer 4, a light-emitting layer 5, an electron transport layer 6, an electron injection layer 7 and a cathode 8 stacked in sequence on a substrate 1, and its device structure is: anode (indium tin oxide (ITO) coated glass substrate) / hole injection layer (HIL) / hole transport layer (HTL) / light-emitting layer (EML) / electron transport layer (ETL) / electron injection layer (EIL) / cathode (Al).

[0271] The materials used to manufacture the organic electroluminescent device are as follows:

[0272]

[0273] The preparation of the organic electroluminescent device comprises the following steps:

[0274] 1) Substrate cleaning:

[0275] The glass substrate coated with transparent ITO is ultrasonically treated in an aqueous cleaning agent (the composition and concentration of the aqueous cleaning agent: ethylene glycol solvent ≤ 10wt%, triethanolamine ≤ 1wt%), then rinsed in deionized water, ultrasonically degreased in a mixed solvent of acetone and ethanol (the volume ratio of acetone to ethanol is 1:1), baked in a clean environment until the moisture is completely removed, and then cleaned with ultraviolet light and ozone.

[0276] 2) Preparation of organic layer:

[0277] Transfer the ITO transparent substrate to the evaporation equipment and evacuate to 1×10 -6 Up to 2×10 -4 Pa, 10nm hole injection layer (HIL) / 80nm hole transport layer (HTL) / 38nm light-emitting layer (EML) / 30nm electron transport layer (ETL) / 1nm electron injection layer (EIL) / 80nm thick cathode (Al) are deposited on the anode film in sequence.

[0278] in:

[0279] The material of the hole injection layer (HIL) is a mixture of NDP-9 and HT, wherein the mass ratio of NDP-9 to HT is 3:97;

[0280] The material of the hole transport layer (HTL) is HT;

[0281] The material of the light-emitting layer (EML) comprises a host material and a guest material, wherein the host material is the compound represented by formula (1) and the compound represented by formula (2) prepared by the present invention, and the guest material is (piq)2Ir(acac); wherein the evaporation method is co-evaporation, and the specific materials and proportions are shown in Table 5;

[0282] The materials of the electron transport layer (ETL) are shown in Table 5, and the evaporation method is co-evaporation;

[0283] The material of the electron injection layer (EIL) is LiQ;

[0284] The cathode is aluminum;

[0285] The partial layers of the organic electroluminescent device and their materials and thicknesses are shown in Table 5.

[0286] Table 5

[0287]

[0288]

[0289]

[0290]

[0291]

[0292] Test Case

[0293] The organic electroluminescent devices obtained from device examples 1 to 23 and comparative examples 1 to 6 in the device examples were tested.

[0294] Instruments: The device's current, voltage, brightness, luminous spectrum and other characteristics are tested synchronously using a PR 650 spectrum scanning luminance meter and a Keithley K 2400 digital source meter system;

[0295] Test conditions: Photoelectric characteristics test conditions: Current density is 10mA / cm2.

[0296] Life test: The current density is 50 mA / cm2, and the time (in hours) when the device brightness drops to 95% of the original brightness is recorded.

[0297] The device performance test results are shown in Table 6:

[0298] Table 6

[0299]

[0300]

[0301] It can be seen from Table 6 that the compound N and the compound M provided by the present invention cooperate with each other and act synergistically. Using them as the main material of the light-emitting layer can effectively reduce the energy level difference between layers, balance the electron and hole transmission rates, and effectively improve the life of the organic electroluminescent diode. At the same time, it can make the device have a lower driving voltage and a higher current efficiency.

[0302] Obviously, the above embodiments are merely examples for the purpose of clear explanation, and are not intended to limit the implementation methods. For those skilled in the art, other different forms of changes or modifications can be made based on the above description. It is not necessary and impossible to list all the implementation methods here. The obvious changes or modifications derived therefrom are still within the scope of protection of the invention.

Claims

1. An organic electroluminescent material, characterized in that: The organic electroluminescent material comprises a first host material and a second host material, wherein the first host material comprises a compound represented by formula (1): Among them, R 1 -R 2 Each is independently selected from hydrogen, or a structure of the following formula (I) or formula (II): L1 and L2 are each independently selected from a single bond, unsubstituted C6-C30 arylene group; n is 1; Ar 1 -Ar 2 Each is independently selected from hydrogen, deuterium, tritium, unsubstituted C6-C30 aryl, and unsubstituted C3-C30 heteroaryl; R T1 -R T8 are independently selected from hydrogen, or R T1 -R T8 Each exists independently or two adjacent rings are connected to form ring B, and the ring B is an unsubstituted C6-C30 aromatic ring; R 3 -R 12 are each independently selected from hydrogen; R 13 , R 14 Each is independently selected from hydrogen, deuterium, unsubstituted C6-C30 aryl or unsubstituted C1-C20 alkyl; The second host material comprises a compound represented by formula (2): The formula (2) is selected from one of the following structures: Among them, X1 ’ -X 12 ’ Each independently selected from N or CR', R' is selected from hydrogen or deuterium; L' is selected from the linking bond; R 16 , R 17 Each is independently selected from an unsubstituted C6-C30 aryl group and an unsubstituted C3-C30 heteroaryl group.

2. The organic electroluminescent material according to claim 1, characterized in that: R 1 -R 2 One of them has the structure represented by formula (I), and the other is hydrogen; L1 is selected from unsubstituted phenylene, unsubstituted biphenylene, unsubstituted terphenylene, and unsubstituted naphthylene.

3. The organic electroluminescent material according to claim 1, characterized in that: L1 is selected from phenylene, biphenylene, and naphthylene.

4. The organic electroluminescent material according to claim 1, characterized in that: L2 is selected from phenylene, biphenylene, and naphthylene.

5. The organic electroluminescent material according to claim 1, characterized in that: Ar 1 -Ar 2 Each is independently selected from the unsubstituted A group: Wherein the A group is selected from one of the following groups: Phenyl, biphenyl, terphenyl, naphthyl, phenanthryl, anthracenyl, triphenylene, pyrenyl, phenylnaphthyl, naphthylphenyl, pyridyl, pyridyl, dibenzofuranyl, dibenzothiophenyl, benzonaphthofuranyl, dinaphthothiophenyl, dinaphthofuranyl, dinaphthothiophenyl, dibenzofuranylphenyl, dibenzothiophenylphenyl, phenyldibenzocarbazolyl, phenylbenzocarbazolyl, phenylcarbazolyl, dibenzocarbazolylphenyl, dimethylfluorenyl, benzodimethylfluorenyl, diphenylfluorenyl, spirobifluorenyl, and dimethylfluorenylphenyl.

6. The organic electroluminescent material according to claim 1, characterized in that: Ar 1 -Ar 2 Each is independently selected from phenyl, biphenyl, dibenzofuranyl, dibenzothiophenyl, benzonaphthofuranyl, dimethylfluorenyl, diphenylfluorenyl, and phenyldibenzocarbazolyl.

7. The organic electroluminescent material according to claim 1, characterized in that: Formula (II) is selected from one of the following structures c-1, c-2, c-3, c-4, c-5, c-6 and c-7: Among them, R T1 -R T8 Each is independently selected from hydrogen, deuterium and tritium.

8. The organic electroluminescent material according to claim 7, characterized in that: R 1 -R 2 One of them has the structure of formula c-4, and the other is hydrogen; wherein R T1 , R T2 , R T7 , R T8 All are hydrogen.

9. The organic electroluminescent material according to claim 1, characterized in that: R 13 , R 14 Each is independently selected from hydrogen, deuterium, and C1-C6 alkyl.

10. The organic electroluminescent material according to claim 1, characterized in that: R 13 , R 14 Each is independently selected from hydrogen, deuterium, methyl, ethyl, phenyl, naphthyl, and biphenyl.

11. The organic electroluminescent material according to claim 1, characterized in that: The formula (1) is selected from one of the following structures:

12. The organic electroluminescent material according to claim 1, characterized in that: In the first host material, the compound represented by formula (1) has any of the following structures: Where D stands for deuterium.

13. The organic electroluminescent material according to claim 1, characterized in that: L' is selected from the linking bond; R 16 , R 17 are each independently selected from unsubstituted E groups, The E group is selected from one of the following groups: phenyl, naphthyl, anthracenyl, biphenyl, terphenyl, phenanthryl, triphenylene, fluorenyl, dimethylfluorenyl, spirobifluorenyl, fluoranthenyl, diphenylfluorenyl, benzodimethylfluorenyl, benzodiphenylfluorenyl, benzospirobifluorenyl, dibenzofuranyl, dibenzothiophenyl, carbazolyl, phenylcarbazolyl, bipyridyl, pyrimidinyl, triazineyl.

14. The organic electroluminescent material according to claim 1, characterized in that: R 16 , R 17 Each is independently selected from phenyl, naphthyl, anthracenyl, biphenyl, dimethylfluorenyl, spirobifluorenyl, diphenylfluorenyl, dibenzofuranyl, and dibenzothiophenyl.

15. The organic electroluminescent material according to claim 1, characterized in that: X1 ’ -X 12 ’ 0-2 of them are selected from N, the others are independently selected from CR', and R' is selected from hydrogen or deuterium.

16. The organic electroluminescent material according to claim 1, characterized in that: X1 ’ -X 12 ’ Each is independently selected from CR', R' is selected from hydrogen or deuterium; or, X1 ’ -X 12 ’ Medium X2 ’ is selected from N, the others are each independently selected from CR', R' is selected from hydrogen or deuterium; or, X1 ’ -X 12 ’ Medium X5 ’ is selected from N, the others are each independently selected from CR', R' is selected from hydrogen or deuterium; or, X1 ’ -X 12 ’ Medium X6 ’ is selected from N, the others are each independently selected from CR', R' is selected from hydrogen or deuterium; or, X1 ’ -X 12 ’ Medium X7 ’ is selected from N, the others are each independently selected from CR', R' is selected from hydrogen or deuterium; or, X1 ’ -X 12 ’ Medium X8 ’ is selected from N, the others are each independently selected from CR', R' is selected from hydrogen or deuterium; or, X1 ’ -X 12 ’ Medium X9 ’ is selected from N, the others are each independently selected from CR', R' is selected from hydrogen or deuterium; or, X1 ’ -X 12 ’ Medium X5 ’ 、X7 ’ is selected from N, the others are each independently selected from CR', and R' is selected from hydrogen or deuterium.

17. The organic electroluminescent material according to claim 1, characterized in that: In the second host material, the compound represented by formula (2) has any of the following structures:

18. The organic electroluminescent material according to claim 1, characterized in that: The mass ratio of the compound represented by formula (1) to the compound represented by formula (2) is 1:9-9:

1.

19. The organic electroluminescent material according to claim 1, characterized in that: The mass ratio of the compound represented by formula (1) to the compound represented by formula (2) is 2:8-8:

2.

20. The organic electroluminescent material according to claim 1, characterized in that: The mass ratio of the compound represented by formula (1) to the compound represented by formula (2) is 3:7-7:

3.

21. The organic electroluminescent material according to claim 1, characterized in that: The mass ratio of the compound represented by formula (1) to the compound represented by formula (2) is 4:6-6:

4.

22. Use of the organic electroluminescent material according to any one of claims 1 to 21 in the preparation of optical devices.

23. An organic electroluminescent device, characterized in that: The organic electroluminescent device comprises an anode and a cathode, and an organic layer disposed between the anode and the cathode, wherein the organic layer comprises the organic electroluminescent material according to any one of claims 1 to 21.

24. The organic electroluminescent device according to claim 23, characterized in that: The light-emitting layer in the organic layer comprises the organic electroluminescent material according to any one of claims 1 to 21.

25. An organic electroluminescent device, characterized in that: The organic electroluminescent device comprises the organic electroluminescent device according to claim 23 or 24.

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