A heterocyclic compound and its applications

Abstract

The present invention relates to the technical field of organic electroluminescent materials, and particularly relates to a heterocyclic compound and its application. The structural formula of the heterocyclic compound is shown as formula (I); the compound shown in formula (I) provided by the present invention has two imidazole structures. When this compound is applied in an organic electroluminescent device, it can significantly reduce the driving voltage, improve the luminous efficiency and lifespan;

Description

Technical Field

[0001] The present invention relates to the technical field of organic electroluminescent materials, and particularly to a heterocyclic compound and its application in an organic light-emitting device. Background Art

[0002] Generally speaking, the organic light-emitting phenomenon refers to the phenomenon of emitting light when an electric current is applied to an organic substance; that is, when an organic layer is disposed between an anode and a cathode, if a voltage is applied between the two electrodes, holes will be injected from the anode into the organic layer, and electrons will be injected from the cathode into the organic layer; when the injected holes and electrons meet, excitons will be formed, and when the excitons transition to the ground state, light and heat will be emitted.

[0003] In recent years, organic electroluminescent display technology has become mature, and some products have entered the market. However, during the industrialization process, there are still many problems to be solved. In particular, for various organic materials used to fabricate devices, there are still many problems that have not been solved, such as the carrier injection and transport performance, the electroluminescent performance of the materials, the service life, the color purity, the matching between various materials and between the materials and the electrodes, etc.; especially for the substances applied to the electron injection layer and the transport layer, as the earliest reports related to electron transport materials, oxadiazole derivatives, triazole derivatives, phenanthroline derivatives and the substances for the representative electron transport layer of imidazole groups recorded in patents such as CN107573328A, CN107556310A, CN113801066A, CN113429395A, CN113429348A, CN114560872A, etc. contain N-phenylbenzimidazole groups in their structures. In terms of function, they not only have the ability to transport electrons but also have the function of blocking holes crossing from the light-emitting layer. However, there is a problem of low thermal stability when applied to actual devices.

[0004] Therefore, in order to overcome the above-mentioned technical problems and further improve the characteristics of organic electroluminescent devices, there is a continuous need to develop more stable and effective substances that can be used as electron injection and transport substances in organic electroluminescent devices.

[0005] In view of this, the present invention is specifically proposed. Summary of the Invention

[0006] The object of the present invention is to provide a heterocyclic compound, which can improve the thermal stability of the material and the ability to transport carriers. The organic electroluminescent device prepared by using this heterocyclic compound can significantly reduce the driving voltage, improve the luminous efficiency and service life; another object of the present invention is to provide the application of this compound.

[0007] Specifically, the present invention provides the following technical solutions:

[0008] The present invention provides a heterocyclic compound, and its structural formula is shown as formula (I):

[0009]

[0010] Wherein,

[0011] L 1 and L 2 each independently selected from the group consisting of a single bond, a substituted or unsubstituted C6-C 60 arylene, or a substituted or unsubstituted C2-C 60 heteroarylene;

[0012] X 1 and X 2 , X 3 and X 4 represent the group of formula (II);

[0013]

[0014] “^” indicates adjacent groups X 1 and X 2 , X 3 and X 4 in formula (I);

[0015] G represents O, S, SO, SO2, Se, CR 3 R 4 , SiR 3 R 4 or NR 5 ;

[0016] is selected from hydrogen, phenyl, biphenyl or pyridyl;

[0017] R 1 , R 2 , R 3 , R 4 , R 5 each independently selected from the group consisting of hydrogen, deuterium, fluorine, cyano, a substituted or unsubstituted C1-C 40 alkyl, a substituted or unsubstituted C1-C 40 alkoxy, a substituted or unsubstituted C2-C 40 alkenyl, a substituted or unsubstituted C1-C 40 alkylthio, a substituted or unsubstituted C1-C 40 alkoxysulfinyl, a substituted or unsubstituted C3-C 40 cycloalkyl, a substituted or unsubstituted C1-C 40 alkylsulfinyl, a substituted or unsubstituted C6-C 60 aryl, a substituted or unsubstituted C6-C 60 aryloxy, a substituted or unsubstituted C6-C60 Arylthio group, substituted or unsubstituted C6-C 60 Arylsulfinyl group, substituted or unsubstituted C3-C 40 Silyl group, substituted or unsubstituted boranyl group, substituted or unsubstituted amino group, substituted or unsubstituted arylphosphino group, substituted or unsubstituted phosphinyl oxide group, or substituted or unsubstituted C2-C 60 A group consisting of heteroaryl; any two or more adjacent substituents may be joined or fused arbitrarily to form a substituted or unsubstituted ring;

[0018] Ar 1 , Ar 2 , Ar 3 , Ar 4 Each independently selected from the group consisting of substituted or unsubstituted C6-C 60 Aryl, substituted or unsubstituted C6-C 60 Fused polycyclic aryl, substituted or unsubstituted C6-C 60 Arylamino group, or substituted or unsubstituted C2-C 60 A group consisting of heteroaryl.

[0019] In the substituted or unsubstituted ring formed by the adjacent groups combined with each other in the present invention, the "ring" means a substituted or unsubstituted hydrocarbon ring or a substituted or unsubstituted heterocyclic ring. A condensed ring means a condensed aliphatic ring, a condensed aromatic ring, a condensed aliphatic heterocyclic ring, a condensed aromatic heterocyclic ring or a form formed by their combination.

[0020] The heterocyclic compound according to the present invention is represented by the above chemical formula (I), wherein it contains heterocycles such as dibenzofuran, dibenzothiophene, dibenzoselenophene, carbazole, etc. and imidazole containing formula (II) are combined through a single bond, arylene, heteroarylene L 1 , L 2 To form a basic skeleton. Compared with the heterocyclic structures such as dibenzofuran, dibenzothiophene, dibenzoselenophene, carbazole, etc. known in the past, the compound represented by formula (I) of the present invention is not only electrochemically stable and has excellent electron mobility, but also has a high glass transition temperature and excellent thermal stability. Therefore, the heterocyclic compound of the present invention has excellent electron transport ability and light-emitting characteristics, and thus can be used as a material for any one of the hole injection layer, hole transport layer, light-emitting layer, electron transport layer and hole blocking layer of the organic layer of an organic electroluminescent element. It is preferably used as a material for any one of the light-emitting layer, electron transport layer and electron transport auxiliary layer further laminated on the electron transport layer, and more preferably used as a material for the electron transport layer or electron transport auxiliary layer.

[0021] Specifically, the compound of formula (I) of the present invention is a heterocyclic compound containing two imidazoles, and thus has stronger electron transport ability compared with heterocycles such as dibenzofuran, dibenzothiophene, dibenzoselenophene, and carbazole with weak electron-withdrawing group ability, and can exhibit relatively high luminous efficiency and high glass transition temperature. Therefore, when the heterocyclic compound of formula (I) of the present invention is used in an organic electroluminescent device, it can not only have excellent thermal stability, carrier transport ability, electron transport ability and luminous ability, but also can reduce the driving voltage of the device, improve the efficiency and lifespan, etc., and as the latest electron transport layer material, it can show an excellent efficiency increase caused by the triplet-triplet fusion effect due to its high triplet energy level.

[0022] In addition, the heterocyclic compound of formula (I) of the present invention has various substituents R 1 , R 2 and Ar 1 , Ar 2 introduced into the basic skeleton, and the HOMO and LUMO energy levels are adjusted according to the types of substituents, so that it can have a wide bandgap and can exhibit high electron transportability in an organic electroluminescent device using such a compound.

[0023] In addition, the heterocyclic compound of formula (I) of the present invention has various substituents L 1 , L 2 and Ar 1 , Ar 2 , especially aryl and / or heteroaryl, introduced into the above basic skeleton, and the molecular weight of the compound is significantly increased, so that the glass transition temperature is increased, and thus it has higher thermal stability than conventional luminescent materials, such as phenanthridine. Therefore, the performance and lifespan characteristics of an organic electroluminescent device containing the compound according to the present invention can be greatly improved. The organic electroluminescent device with such improved performance and lifespan characteristics can ultimately maximize the performance of a full-color organic light-emitting panel.

[0024] The heterocyclic compound of formula (I) of the present invention, preferably, the heterocyclic compound is selected from the group consisting of the following structures:

[0025]

[0026] Among them, the meanings of Ar 1 , Ar 2 , Ar 3 , Ar 4 , L 1 , IL 2 , G, R 1 , R 2 are the same as those defined above.

[0027] Preferably, the R 1 , R 2 , R 3 , R 4 each independently is a group consisting of hydrogen, deuterium, methyl, substituted or unsubstituted phenyl, and substituted or unsubstituted fluorenyl.

[0028] According to an embodiment of the present invention, the R 1 , R 2 is selected from hydrogen or deuterium.

[0029] According to an embodiment of the present invention, the R 3 , R 4 , R 5 each independently is selected from the group consisting of hydrogen, deuterium, methyl, phenyl, biphenyl, terphenyl, naphthyl, phenanthryl, triphenylene, carbazolyl, fluorenyl, dibenzofuran, or dibenzothiophene.

[0030] An aryl in the sense of the present invention contains 6 to 60 carbon atoms, a heteroaryl contains 2 to 60 carbon atoms and at least one heteroatom, provided that the sum of the carbon atoms and the heteroatoms is at least 5; the heteroatom is preferably selected from N, O, or S. At this time, two or more rings of the heteroaryl may be simply attached to each other or attached in a condensed form, and further, a form condensed with an aryl may also be included. As non-limiting examples of such heteroaryls, there may be mentioned monocyclic six-membered rings such as pyridyl, pyrazinyl, pyrimidinyl, pyridazinyl, and triazinyl; polycyclic rings such as phenoxathiinyl, indolizinyl, indolyl, purinyl, quinolinyl, benzothiazolyl, and carbazolyl; and 2-furyl, N-imidazolyl, 2-isoxazolyl, 2-pyridyl, 2-pyrimidinyl, etc.

[0031] Furthermore, the aryl, heteroaryl, or heteroaromatic ring is preferably selected from the group consisting of phenyl, naphthyl, anthracenyl, benzoanthracenyl, phenanthryl, pyrenyl, Groups consisting of a base, a perylene base, a fluoranthene base, a tetracenyl, a pentacenyl, a benzopyrene base, a biphenyl group, an azobenzene group, a terphenyl group, a triphenylphenyl group, a quaterphenyl group, a fluorene group, a spirobifluorene group, a dihydrophenanthrene group, a triphenylene group, a dihydropyrene group, a tetrahydropyrene group, a cis- or trans-indeno[1,2-b]fluorene group, a cis- or trans-indeno[2,1-b]carbazole group, an indolocarbazole group, a benzofurocarbazole group, a benzothienocarbazole group, a benzocarbazole group, a dibenzocarbazole group, aza-dibenzo[g,ij]naphtho[2,1,8-cde]azulene, a trindene group, an isotrindene group, a spirotrindene group, a spiroisotrindene group, a furan group, a benzofuran group, an isobenzofuran group, a dibenzofuran group, a thiophene group, a benzothiophene group, an isobenzothiophene group, a dibenzothiophene group, a pyrrole group, an indole group, an isoindole group, a carbazole group, a pyridine group, a quinoline group, an isoquinoline group, an acridine group, a phenanthridine group, a benzo[5,6]quinoline group, a benzo[6,7]quinoline group, a benzo[7,8]quinoline group, a phenothiazine group, a phenoxazine group, a pyrazole group, an indazole group, an imidazole group, a benzimidazole group, a naphthimidazole group, a phenanthrimidazole group, a pyridinimidazole group, a pyrazinimidazole group, a quinoxalinimidazole group, an oxazole group, a benzoxazole group, a naphthoxazole group, an anthroxazole group, a phenanthroxazole group, an isoxazole group, a 1,2-thiazole group, a 1,3-thiazole group, a benzothiazole group, a pyridazine group, a hexaazatriphenylene group, a benzopyridazine group, a pyrimidine group, a benzopyrimidine group, a quinoxaline group, a 1,5-diazaanthracene group, a 2,7-diazapyrene group, a 2,3-diazapyrene group, a 1,6-diazapyrene group, a 1,8-diazapyrene group, a 4,5-diazapyrene group, a 4,5,9,10-tetraazaperylene group, a pyrazine group, a phenazine group, a phenoxazine group, a phenothiazine group, a fluoranthene ring group, a naphthyridine group, an azacarbazole group, a benzocarbazole group, a carbazole group, a phenanthroline group, a 1,2,3-triazole group, a 1,2,4-triazole group, a benzotriazole group, a 1,2,3-oxadiazole group, a 1,2,4-oxadiazole group, a 1,2,5-oxadiazole group, a 1,3,4-oxadiazole group, a 1,2,3-thiadiazole group, a 1,2,4-thiadiazole group, a 1,2,5-thiadiazole group, a 1,3,4-thiadiazole group, a 1,3,5-triazine group, a 1,2,4-triazine group, a 1,2,3-triazine group, a tetrazole group, a 1,2,4,5-tetrazine group, a 1,2,3,4-tetrazine group, a 1,2,3,5-tetrazine group, a purine group, a pteridine group, an indazole group, a quinazoline group, a benzothiadiazole group, or a group derived from a combination of these systems.

[0032] According to an embodiment of the present invention, the Ar 1 , Ar 2 , Ar 3 , Ar 4 , R 5 is selected from the group consisting of substituted or unsubstituted groups: phenyl, naphthyl, anthracenyl, benzanthracenyl, phenanthrenyl, pyrenyl, a base, a perylene group, a fluoranthene group, a tetracenyl group, a pentacenyl group, a benzopyrenyl group, a biphenyl group, an azobenzene group, a terphenyl group, a triphenylphenyl group, a quaterphenyl group, a fluorenyl group, a spirobifluorenyl group, a dihydrophenanthrenyl group, a triphenylene group, a dihydropyrenyl group, a tetrahydropyrenyl group, a cis- or trans-indeno[1,2-b]fluorene group, a cis- or trans-indeno[2,1-b]carbazole group, an indolocarbazole group, a benzofuro[3,2-b]carbazole group, a benzothieno[3,2-b]carbazole group, a benzocarbazole group, a dibenzocarbazole group, aza-dibenzo[g,ij]naphtho[2,1,8-cde]azulene, a trindene group, an isotrindene group, a spirotrindene group, a spiroisotrindene group, a furyl group, a benzofuryl group, an isobenzofuryl group, a dibenzofuryl group, a thienyl group, a benzothienyl group, an isobenzothienyl group, a dibenzothienyl group, a pyrrolyl group, an indolyl group, an isoindolyl group, a carbazolyl group, a pyridyl group, a quinolinyl group, an isoquinolinyl group, an acridinyl group, a phenanthridinyl group, a benzo[5,6]quinolinyl group, a benzo[6,7]quinolinyl group, a benzo[7,8]quinolinyl group, a phenothiazinyl group, a phenoxazinyl group, a pyrazolyl group, an indazolyl group, an imidazolyl group, a benzimidazolyl group, a naphthimidazolyl group, a phenanthrimidazolyl group, a pyridinimidazolyl group, a pyrazinimidazolyl group, a quinoxalinimidazolyl group, an oxazolyl group, a benzoxazolyl group, a naphthoxazolyl group, an anthroxazolyl group, a phenoxazolyl group, an isoxazolyl group, a 1,2-thiazolyl group, a 1,3-thiazolyl group, a benzothiazolyl group, a pyridazinyl group, a hexaazatriphenylene group, a benzopyridazinyl group, a pyrimidinyl group, a benzopyrimidinyl group, a quinoxalinyl group, a 1,5-diazaanthracenyl group, a 2,7-diazapyrenyl group, a 2,3-diazapyrenyl group, a 1,6-diazapyrenyl group, a 1,8-diazapyrenyl group, a 4,5-diazapyrenyl group, a 4,5,9,10-tetraazaperylene group, a pyrazinyl group, a phenazinyl group, a phenoxazinyl group, a phenothiazinyl group, a fluoranthene ring group, a naphthyridinyl group, an aza-carbazolyl group, a benzocarbazolyl group, a carbazolyl group, a phenanthroline group, a 1,2,3-triazolyl group, a 1,2,4-triazolyl group, a benzotriazolyl group, a 1,2,3-oxadiazolyl group, a 1,2,4-oxadiazolyl group, a 1,2,5-oxadiazolyl group, a 1,3,4-oxadiazolyl group, a 1,2,3-thiadiazolyl group, a 1,2,4-thiadiazolyl group, a 1,2,5-thiadiazolyl group, a 1,3,4-thiadiazolyl group, a 1,3,5-triazinyl group, a 1,2,4-triazinyl group, a 1,2,3-triazinyl group, a tetrazolyl group, a 1,2,4,5-tetrazinyl group, a 1,2,3,4-tetrazinyl group, a 1,2,3,5-tetrazinyl group, a purinyl group, a pteridinyl group, an indazyl group, a quinazolinyl group, a benzothiadiazolyl group or a group derived from a combination of these systems.

[0033] In the heterocyclic compound represented by formula (I) of the present invention, L 1 , L 2 is a functional group connecting the heterocyclic skeleton containing two imidazoles and the above-mentioned Ar 1 , Ar 2 , and can be selected from the group consisting of a single bond, an arylene group of C6-C 60 and a heteroarylene group of C2-C 60 . At this time, preferably, the L1 , L 2 are each independently selected from a single bond or the group consisting of the groups represented by the following III-1 to III-23:

[0034]

[0035] wherein the dashed line represents the bonding site of the group. At this time, the bonding positions of the groups represented by the above formulas III-1 to III-23 are not limited, and ortho, meta, or para is acceptable. The above L 1 , L 2 may each independently be selected from one or more substituents selected from the group consisting of deuterium, a halogen atom, a nitrile group, a C1-C 40 alkyl group, a C6-C 60 aryl group, and a C2-C 60 heteroaryl group. At this time, when there are multiple substituents, it is preferred that the multiple substituents are the same or different from each other.

[0036] In the present invention, the term "substituted or unsubstituted" means being substituted or unsubstituted by one or more substituents selected from hydrogen, deuterium, a halogen atom, a hydroxyl group, a nitrile group, a nitro group, an amino group, an amidino group, a hydrazino group, a hydrazono group, a carboxyl group or its carboxylate, a sulfonic acid group or its sulfonate, a phosphoric acid group or its phosphate, a C1-C 40 alkyl group, a C2-C 40 alkenyl group, a C2-C 40 alkynyl group, a C1-C 40 alkoxy group, a C3-C 40 cycloalkyl group, a C3-C 40 cycloalkenyl group, a C6-C 60 aryl group, a C6-C 60 aryloxy group, a C6-C 60 arylthioether group, and a C2-C 60 heteroaryl group, or being substituted or unsubstituted by a substituent formed by connecting two or more of the above-exemplified substituents.

[0037] For the alkyl group in the sense of the present invention, it contains 1 to 40 carbon atoms, and is a straight-chain alkyl group or a branched alkyl group in which a single hydrogen atom or -CH2- group may further be substituted; the alkenyl group or alkynyl group contains at least two carbon atoms. As non-limiting examples, the alkyl group, alkenyl group, or alkynyl group is preferably considered to refer to the following groups: methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, sec-butyl, tert-butyl, 2-methylbutyl, n-pentyl, sec-pentyl, neopentyl, cyclopentyl, n-hexyl, neohexyl, cyclohexyl, n-heptyl, cycloheptyl, n-octyl, cyclooctyl, 2-ethylhexyl, cyclohexenyl, heptenyl, cycloheptenyl, octenyl, cyclooctenyl, ethynyl, propynyl, butynyl, pentynyl, hexynyl, heptynyl, or octynyl.

[0038] An alkoxy group preferably having 1 to 40 carbon atoms is considered to be a methoxy group, a trifluoromethoxy group, an ethoxy group, a n-propoxy group, an isopropoxy group, a n-butoxy group, an isobutoxy group, a sec-butoxy group, a tert-butoxy group, a n-pentyloxy group, a sec-pentyloxy group, a 2-methylbutoxy group, a n-hexyloxy group, a cyclohexyloxy group, a n-heptyloxy group, a cycloheptyloxy group, a n-octyloxy group, a cyclooctyloxy group, a 2-ethylhexyloxy group, a pentafluoroethoxy group, and a 2,2,2-trifluoroethoxy group.

[0039] A heteroalkyl group preferably having 1 to 40 carbon atoms is an alkyl group in which a single hydrogen atom or -CH2- group is replaced by an oxygen, sulfur, or halogen atom. As non-limiting examples, there are alkoxy groups, alkylthio groups, fluorinated alkoxy groups, fluorinated alkylthio groups, and particularly a methoxy group, an ethoxy group, a n-propoxy group, an isopropoxy group, a n-butoxy group, an isobutoxy group, a sec-butoxy group, a tert-butoxy group, a methylthio group, an ethylthio group, a n-propylthio group, an isopropylthio group, a n-butylthio group, an isobutylthio group, a sec-butylthio group, a tert-butylthio group, a trifluoromethylthio group, a trifluoromethoxy group, a pentafluoroethoxy group, a pentafluoroethylthio group, a 2,2,2-trifluoroethoxy group, a 2,2,2-trifluoroethylthio group, a vinyloxy group, a vinylthio group, an allyloxy group, an allylthio group, a butenylthio group, a butenyloxy group, a pentenyloxy group, a pentenylthio group, a cyclopentenoxy group, a cyclopentenylthio group, a hexenyloxy group, a hexenylthio group, a cyclohexenyloxy group, a cyclohexenylthio group, an ethynyloxy group, an ethynylthio group, a propynyloxy group, a propynylthio group, a butynyloxy group, a butynylthio group, a pentynyloxy group, a pentynylthio group, a hexynyloxy group, a hexynylthio group.

[0040] Generally, the cycloalkyl group and cycloalkenyl group according to the present invention can be a cyclopropyl group, a cyclobutyl group, a cyclopentyl group, a cyclohexyl group, a cyclobutenyl group, a cyclopentenyl group, a cyclohexenyl group, a cycloheptyl group, a cycloheptenyl group, in which one or more -CH2- groups can be replaced by the above groups; in addition, one or more hydrogen atoms can also be replaced by a deuterium atom, a halogen atom, or a nitrile group.

[0041] The heteroalkyl group used in the present invention refers to a monovalent functional group obtained by removing one hydrogen atom from a non-aromatic hydrocarbon having 3 to 40 nuclear atoms. At this time, one or more carbons in the ring, preferably 1 to 3 carbons, are replaced by heteroatoms such as N, O, or S. As non-limiting examples, there are tetrahydrofuran, tetrahydrothiophene, morpholine, piperazine, etc.

[0042] The fused polycyclic aryl group used in the present invention refers to a monovalent functional group obtained by removing one hydrogen atom from an aromatic hydrocarbon having 6 to 60 carbon atoms in which two or more rings are combined. At this time, two or more rings can be simply attached to each other or attached in a condensed form. As non-limiting examples, there are, for example, a phenanthryl group, an anthryl group, a fluoranthenyl group, a pyrenyl group, a triphenylenyl group, a perylenyl group, a group, etc.

[0043] The arylamino group used in the present invention refers to an amine substituted with an aryl group having 6 to 60 carbon atoms. Non-limiting examples of the arylamino group include diphenylamino group, N-phenyl-1-naphthylamino group, N-(1-naphthyl)-2-naphthylamino group, etc. The heteroarylamino group refers to an amine substituted with an aryl group having 6 to 60 carbon atoms and a heteroaryl group having 2 to 60 carbon atoms. Non-limiting examples of the heteroarylamino group include N-phenylpyridin-3-ylamino group, N-([1,1'-biphenyl]-4-yl)dibenz[b,d]furan-2-ylamino group, N-([1,1'-biphenyl]-4-yl)-9,9-dimethyl-9H-fluoren-2-ylamino group, etc.

[0044] The alkoxy group used in the present invention refers to RO - The monovalent functional group represented, wherein R is an alkyl group having 1 to 40 carbon atoms, and may include a straight-chain, branched-chain or cyclic structure. Non-limiting examples of such an alkoxy group include methoxy group, ethoxy group, n-propoxy group, 1-propoxy group, tert-butoxy group, n-butoxy group, pentyloxy group, cyclopentyloxy group, cyclohexyloxy group, etc.

[0045] The aryloxy group used in the present invention refers to R'O - The monovalent functional group represented, wherein the above R' is an aryl group having 6 to 60 carbon atoms. Non-limiting examples of such an aryloxy group include phenoxy group, naphthyloxy group, biphenyloxy group, etc.

[0046] The alkylsilyl group used in the present invention refers to a silyl group substituted with an alkyl group having 1 to 40 carbon atoms, and the number of carbon atoms constituting the alkylsilyl group is at least 3. Non-limiting examples of the alkylsilyl group include trimethylsilyl group, triethylsilyl group, etc. The arylsilyl group refers to a silyl group substituted with an aryl group having 6 to 60 carbon atoms.

[0047] The arylphosphino group used in the present invention refers to a diarylphosphino group substituted with an aryl group having 6 to 60 carbon atoms. Non-limiting examples of the arylphosphino group include diphenylphosphino group, bis(4-trimethylsilylphenyl)phosphino group, etc. The aryloxyphosphino group is that the phosphorus atom of the diarylphosphino group is oxidized to the highest valence state.

[0048] The arylboron group used in the present invention refers to a diarylboron group substituted with an aryl group having 6 to 60 carbon atoms. Non-limiting examples of the arylboron group include diphenylboron group, bis(2,4,6-trimethylphenyl)boron group, etc. The alkylboron group refers to a dialkylboron group substituted with an alkyl group having 1 to 40 carbon atoms. Non-limiting examples of the alkylboron group include di-tert-butylboron group, diisobutylboron group, etc.

[0049] Preferably, the heterocyclic compound is selected from the compounds represented by the following formulas J475-J543:

[0050]

[0051]

[0052]

[0053]

[0054] Among them, T is selected from O, S, SO, Se or NPh; Ph represents a phenyl group.

[0055] The present invention also provides an organic electroluminescent material, the raw materials of which include the above-mentioned heterocyclic compound; the organic electroluminescent material including the heterocyclic compound of the present invention has the ability of carrier transport.

[0056] The present invention also provides the application of the above-mentioned heterocyclic compound in the preparation of an organic electroluminescent device.

[0057] The present invention also provides an organic electroluminescent device, which includes: a first electrode, a second electrode, a capping layer, and more than one organic layer disposed between the first electrode and the second electrode; at least one layer of the organic layer or the capping layer includes the above-mentioned heterocyclic compound.

[0058] The organic electroluminescent device includes a cathode, an anode, and at least one light-emitting layer. In addition to these layers, it may also include other layers, for example, in each case, including one or more hole injection layers, hole transport layers, hole blocking layers, electron transport layers, electron injection layers, exciton blocking layers, electron blocking layers, and / or charge generation layers. An intermediate layer having, for example, an exciton blocking function can also be introduced between two light-emitting layers. However, it should be noted that not each of these layers must be present. The organic electroluminescent device described herein may include one light-emitting layer, or it may include multiple light-emitting layers. That is, a variety of light-emitting compounds capable of emitting light are used in the light-emitting layer. A system having three light-emitting layers is particularly preferred, and the three layers may exhibit blue, green, and red light emission. If there are more than one light-emitting layer, according to the present invention, at least one of these layers includes the heterocyclic compound of the present invention.

[0059] Furthermore, the organic electroluminescent device according to the present invention does not include a separate hole injection layer and / or hole transport layer and / or hole blocking layer and / or electron transport layer, that is, the light-emitting layer is directly adjacent to the electron blocking layer or hole transport layer or anode, and / or the light-emitting layer is directly adjacent to the electron transport layer or electron injection layer or cathode.

[0060] In the other layers of the organic electroluminescent element according to the invention, especially in the hole injection and hole transport layers and in the electron injection and electron transport layers, all materials can be used in the manner commonly used according to the prior art. A person of ordinary skill in the art will thus be able to use in combination with the light-emitting layer according to the invention all materials known for organic electroluminescent elements without creative effort.

[0061] Furthermore, preference is given to an organic electroluminescent element in which one or more layers are applied by means of a sublimation method, where the material is applied by vapor deposition in a vacuum sublimation apparatus at an initial pressure of less than 10 -5 Pa, preferably less than 10 -6 Pa. However, the initial pressure can also be even lower, for example less than 10 -7 Pa.

[0062] Also preferred is an organic electroluminescent element in which one or more layers are applied by means of an organic vapor deposition method or by means of carrier gas sublimation, where the material is applied at a pressure between 10 -5 Pa and 1 Pa. A particular example of this method is the organic vapor jet printing method, where the material is applied directly through a nozzle and is thus structured.

[0063] Furthermore, preference is given to an organic electroluminescent element in which one or more layers are produced from a solution, for example by spin coating, or by means of any desired printing method such as screen printing, flexographic printing, lithographic printing, photothermographic imaging, thermal transfer, inkjet printing or nozzle printing. Soluble compounds are obtained, for example, by appropriate substitution. These methods are also particularly suitable for oligomers, dendrimers and polymers. Also feasible are hybrid methods, where, for example, one or more layers are applied from a solution and one or more additional layers are applied by vapor deposition.

[0064] These methods are generally known to a person of ordinary skill in the art, and they can apply them to an organic electroluminescent element comprising a compound according to the invention without creative effort.

[0065] Accordingly, the invention also relates to a method for manufacturing an organic electroluminescent element according to the invention, where at least one layer is applied by means of a sublimation method, and / or at least one layer is applied by means of an organic vapor deposition method or by means of carrier gas sublimation, and / or at least one layer is applied from a solution by spin coating or by means of a printing method.

[0066] In addition, the present invention relates to a heterocyclic compound of the present invention containing at least one of those indicated above. The same preferred cases as those indicated above with respect to the organic electroluminescent element apply to the compounds of the present invention. In particular, other compounds may preferably be included in addition to the heterocyclic compound. Processing the heterocyclic compound of the present invention from a liquid phase, for example, by spin coating or by a printing method, requires a preparation for processing the compound of the present invention. These preparations may be, for example, solutions, dispersions or emulsions. For this purpose, a mixture of two or more solvents may preferably be used. Suitable and preferred solvents are, for example, toluene, anisole, o-xylene, m-xylene or p-xylene, methyl benzoate, mesitylene, decalin, o-dimethoxybenzene, tetrahydrofuran, methyltetrahydrofuran, tetrahydropyran, chlorobenzene, dioxane, phenyltoluenes, especially 3-phenyltoluene, (-)-fenchone, 1,2,3,5-tetramethylbenzene, 1,2,4,5-tetramethylbenzene, 1-methylnaphthalene, 2-methylbenzothiazole, 2-phenoxyethanol, 2-pyrrolidone, 3-methylanisole, 4-methylanisole, 3,4-dimethylanisole, 3,5-dimethylanisole, acetophenone, α-terpineol, benzothiazole, butyl benzoate, cumene, cyclohexanol, cyclohexanone, cyclohexylbenzene, decahydronaphthalene, dodecylbenzene, ethyl benzoate, indane, methyl benzoate, 1-methylpyrrolidone, p-methylcumene, phenetole, 1,4-diisopropylbenzene, dibenzyl ether, diethylene glycol butyl methyl ether, triethylene glycol butyl methyl ether, diethylene glycol dibutyl ether, triethylene glycol dimethyl ether, diethylene glycol monobutyl ether, tripropylene glycol dimethyl ether, tetraethylene glycol dimethyl ether, 2-isopropylnaphthalene, pentylbenzene, hexylbenzene, heptylbenzene, octylbenzene, 1,1-bis(3,4-dimethylphenyl)ethane, or a mixture of these solvents.

[0067] Preferably, the organic layer includes a hole injection layer, a hole transport layer, a hole blocking layer, a light emitting layer, an electron transport layer, an electron injection layer or an electron blocking layer.

[0068] The present invention also provides a consumer product including the organic electroluminescent element described above.

[0069] In addition, unless otherwise specified, the raw materials used in the present invention can be obtained through commercial purchase. Any range described in the present invention includes the end values and any numerical value between the end values, as well as any sub-range constituted by any numerical value between the end values or the end values.

[0070] The beneficial effects achieved by the present invention:

[0071] The heterocyclic compound represented by formula (I) provided by the present invention can be applied to the organic layer of an organic electroluminescent element due to its excellent electron mobility, thermal stability, and luminescence characteristics. In particular, when the heterocyclic compound represented by formula (I) of the present invention is used for the electron transport layer and the electron transport auxiliary layer, an organic electroluminescent element having a lower driving voltage, higher efficiency, and longer lifespan compared to conventional electron transport materials can be manufactured. Furthermore, a full-color display panel with improved performance and lifespan can also be manufactured. BRIEF DESCRIPTION OF THE DRAWINGS

[0072] Figure 1 A schematic diagram of an organic light-emitting device 100 is shown. The illustration is not necessarily drawn to scale. The device 100 may include a substrate 101, an anode layer 102, a hole injection layer 103, a hole transport layer 104, an electron blocking layer 105, an organic light-emitting layer 106, a hole blocking layer 107, an electron transport layer 108, an electron injection layer 109, a cathode 110, and a capping layer (CPL) 111. The device 100 can be manufactured by sequentially depositing the described layers.

[0073] Figure 2 A schematic diagram of an organic light-emitting device 200 with two light-emitting layers is shown. The device includes a substrate 201, an anode 202, a hole injection 203, a hole transport layer 204, a first light-emitting layer 205, an electron transport layer 206, a charge generation layer 207, a hole injection layer 208, a hole transport layer 209, a second light-emitting layer 210, an electron transport layer 211, an electron injection layer 212, and a cathode 213. The device 200 can be prepared by sequentially depositing the described layers. Since the most common OLED device has one light-emitting layer, while the device 200 has a first light-emitting layer and a second light-emitting layer, the emission peak shapes of the first light-emitting layer and the second light-emitting layer can be overlapping, or cross-overlapping, or non-overlapping. In the corresponding layers of the device 200, materials similar to those described for the device 100 can be used. Figure 2 An example of how to add some layers to the structure of the device 100 is provided. DETAILED DESCRIPTION

[0074] The following examples are used to illustrate the present invention, but do not limit the scope of the present invention.

[0075] In the description of the present invention, unless otherwise specified, "a plurality of" means two or more; the orientation or positional relationship indicated by terms such as "upper", "lower", etc. is based on the orientation or positional relationship shown in the drawings, and is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be construed as a limitation of the present invention.

[0076] Unless otherwise specified, the experimental methods used in the following examples are all conventional methods. Unless otherwise specified, the experimental raw materials and related equipment used in the following examples can all be obtained through commercial channels. Unless otherwise specified, the percentages are all mass percentages.

[0077] The test instruments and methods for testing the performance of OLED materials and components in the following examples are as follows:

[0078] OLED component performance detection conditions:

[0079] Luminance and chromaticity coordinates: Measured using a spectral scanner PhotoResearch PR-715;

[0080] Current density and turn-on voltage: Measured using a digital source meter Keithley 2420;

[0081] Power efficiency: Measured using a NEWPORT 1931-C.

[0082] Example 1

[0083] The preparation method of compound J475, taking T = S as an example, includes the following steps:

[0084] The first step: Preparation of intermediate Int-1

[0085]

[0086] Under nitrogen protection, 40.0 mmol of phenylacetylene (reactant 2), 20.0 mmol of 2,5-dibromo-3,4-dicyanothiophene (reactant 1), 4.0 mmol of copper iodide, 4.0 mmol of PdCl2(PPh3)2, 8.0 mmol of triphenylphosphine and 80 mL of triethylamine were mixed, heated to reflux and stirred for 15 hours, cooled to room temperature, concentrated and dried under reduced pressure, and purified by silica gel column chromatography to obtain compound Int-1, a yellow solid, with a yield of 86%.

[0087] The second step: Preparation of intermediate Int-2

[0088]

[0089] Under nitrogen protection, 20.0 mmol of Int-1 prepared in the previous step, 80.0 mmol of nitromethane, 80.0 mmol of potassium hydroxide and 60 mL of DMSO were mixed, heated to 110 °C, stirred for 45 minutes, cooled to room temperature, the reaction solution was poured into 150 mL of ice water, filtered, the filter cake was washed with water and recrystallized from methanol to obtain compound Int-2, a yellow solid, with a yield of 85%.

[0090] Step 3: Preparation of Intermediate Int-3

[0091]

[0092] 20.0 mmol of Int-2 prepared in the previous step was dissolved in 100 mL of dichloromethane, 60.0 mmol of pyridine was added, the temperature was lowered to 0 °C, 42.0 mmol of benzoyl chloride (Reactant 3) was added dropwise, the mixture was stirred at room temperature for 15 hours, 50 mL of dilute hydrochloric acid was added, the organic phase was separated, the aqueous phase was extracted with dichloromethane, the organic phases were collected, washed with water, dried, filtered, and the filtrate was concentrated and dried under reduced pressure to obtain Compound Int-3, a yellow solid, with a yield of 95%.

[0093] Step 4: Preparation of Intermediate Int-4

[0094]

[0095] 20.0 mmol of Int-3 prepared in the previous step was mixed with 100 mL of ethanol, 0.2 g of 10% palladium / carbon was added, hydrogen was introduced under atmospheric pressure, the mixture was stirred at room temperature for 15 hours, filtered, and the filtrate was concentrated and dried under reduced pressure to obtain Compound Int-4, a yellow solid, with a yield of 100%.

[0096] Step 5: Preparation of Intermediate Int-5

[0097]

[0098] Under nitrogen protection, 20.0 mmol of Int-4 prepared in the previous step, 40.0 mmol of bromobenzene (Reactant 4), 60.0 mmol of sodium tert-butoxide and 100 mL of toluene were mixed, 0.2 mmol of Pa2(dba)3 and 0.4 mmol of Xantphos were added, the temperature was raised to 90 °C and the mixture was stirred for 15 hours, cooled to room temperature, 50 mL of water was added, filtered, and the filter cake was washed with water and ethanol to obtain Compound Int-5, a yellow solid, with a yield of 80%.

[0099] Step 6: Preparation of Compound J475

[0100]

[0101] Under nitrogen protection, 20.0 mmol of Int-5 prepared in the previous step, 2.0 mmol of p-toluenesulfonic acid and 100 mL of toluene were mixed, heated to reflux and stirred for 12 hours, and the water generated in the reaction was separated through a water separator, cooled to room temperature, concentrated and dried under reduced pressure, and purified by silica gel column chromatography to obtain Compound J475, T = S, a white solid, with a yield of 87%, MS(TOF) m / z: 721.2364; 1HNMR (δ, CDCl3): 8.07 - 8.02 (4H, m); 7.98 (2H, s); 7.86 - 7.82 (4H, m); 7.62 - 7.54 (8H, m); 7.52 - 7.47 (6H, m); 7.43 - 7.36 (6H, m); 7.33 - 7.28 (2H, m).

[0102] T = O, white solid, yield 90%, MS (TOF) m / z: 705.2588; 1 HNMR (δ, CDCl3): 8.26 - 8.22 (4H, m); 8.15 (2H, s); 8.07 - 8.02 (4H, m); 7.65 - 7.61 (4H, m); 7.58 - 7.54 (4H, m); 7.51 - 7.46 (6H, m); 7.43 - 7.38 (6H, m); 7.35 - 7.31 (2H, m).

[0103] T = Se, white solid, yield 82%, MS (TOF) m / z: 769.1886; 1 HNMR (δ, CDCl3): 8.36 - 8.34 (2H, t); 8.07 - 8.01 (4H, m); 7.77 - 7.73 (4H, m); 7.63 - 7.53 (8H, m); 7.50 - 7.43 (6H, m); 7.41 - 7.36 (6H, m); 7.33 - 7.30 (2H, m).

[0104] T = NPh, white solid, yield 85%, MS (TOF) m / z: 780.3063; 1 HNMR (δ, CDCl3): 8.21 (2H, s); 8.07 - 8.02 (4H, m); 7.98 - 7.94 (4H, m); 7.69 - 7.62 (6H, m); 7.60 - 7.54 (6H, m); 7.52 - 7.46 (6H, m); 7.43 - 7.36 (6H, m); 7.33 - 7.27 (3H, m).

[0105] Refer to the similar synthesis method above to prepare the compounds shown in Table 1 below:

[0106] Table 1

[0107]

[0108]

[0109]

[0110] Example 2

[0111] Preparation method of compound J532, comprising the following steps:

[0112] First step: Preparation of intermediate Int-6

[0113]

[0114] Referring to the synthesis method of the first step in Example 1, replace 2,5-dibromo-3,4-dicyanothiophene in the first step of Example 1 with 2,5-dibromo-3,4-dicyanofuran or 2,5-dibromo-3,4-dicyano-1-phenylpyrrole, etc., and replace phenylacetylene with 2-ethynyl-1-phenylbenzo[d]imidazole to prepare intermediate Int-6, with a yield of 80% - 85%.

[0115] Second step: Preparation of intermediate Int-7

[0116]

[0117] Referring to the synthesis method of the second step in Example 1, only replace Int-1 in the second step of Example 1 with Int-6 to prepare intermediate Int-7, with a yield of 85% - 90%.

[0118] Third step: Preparation of intermediate Int-8

[0119]

[0120] Under nitrogen protection, 10.0 mmol of intermediate Int-7, 10.0 mmol of o-bromoiodobenzene, 25.0 mmol of cesium carbonate, 0.01 mmol of Pd2(dba)3 catalyst, 0.02 mmol of Xantphos and 100 mL of toluene were heated to 100 °C and stirred for 15 hours, cooled to room temperature, diluted with 50 mL of water, extracted with dichloromethane, the organic phase was collected, dried, filtered, the filtrate was concentrated and dried under reduced pressure, and purified by silica gel column chromatography to obtain compound Int-8, a yellow solid, with a yield of 80% - 85%.

[0121] Fourth step: Preparation of intermediate Int-9

[0122]

[0123] Referring to the synthesis method of the fourth step in Example 1, only replace Int-3 in the fourth step of Example 1 with Int-8 to prepare intermediate Int-9, with a yield of 100%.

[0124] Fifth step: Preparation of intermediate Int-10

[0125]

[0126] Referring to the synthesis method in the third step of Example 1, only replace Int-2 in the third step of Example 1 with Int-9 to prepare intermediate Int-10, with a yield of 90% - 95%.

[0127] Step 6: Preparation of Compound J532

[0128]

[0129] Referring to the synthesis method in the sixth step of Example 1, only replace Int-5 in the sixth step of Example 1 with Int-10 to prepare Compound J532;

[0130] T = S; Yellow solid, yield 89%, MS (MALDI-TOF): m / z = 875.2721 [M+H] + ; 1 HNMR (δ, CDCl3): 8.44 (2H, s); 8.21 - 8.10 (8H, m); 8.78 - 8.69 (4H, m); 7.61 - 7.52 (8H, m); 7.49 - 8.43 (6H, m); 7.37 - 7.32 (2H, m); 7.26 - 7.18 (4H, m).

[0131] T = O; Yellow solid, yield 87%, MS (MALDI-TOF): m / z = 859.2868 [M+H] + ; 1 HNMR (δ, CDCl3): 8.54 (2H, s); 8.23 - 8.12 (8H, m); 7.79 - 7.70 (4H, m); 7.61 - 7.52 (8H, m); 7.49 - 8.43 (6H, m); 7.37 - 7.32 (2H, m); 7.26 - 7.18 (4H, m).

[0132] T = Se; Yellow solid, yield 81%, MS (MALDI-TOF): m / z = 923.2164 [M+H] + ; 1 HNMR (δ, CDCl3): 8.76 (2H, s); 8.23 - 8.12 (8H, m); 7.78 - 7.68 (4H, m); 7.61 - 7.52 (8H, m); 7.49 - 8.43 (6H, m); 7.37 - 7.32 (2H, m); 7.26 - 7.18 (4H, m).

[0133] T = NPh; Yellow solid, yield 85%, MS (MALDI-TOF): m / z = 934.3342 [M+H] + ; 1HNMR (δ, CDCl3): 8.76 (2H, s); 8.23 - 8.19 (6H, m); 8.16 - 8.12 (2H, m); 7.78 - 7.66 (6H, m); 7.61 - 7.52 (8H, m); 7.50 - 7.42 (8H, m); 7.37 - 7.29 (3H, m); 7.26 - 7.18 (4H, m).

[0134] Refer to the similar synthesis method above to prepare the compounds shown in Table 2 below:

[0135] Table 2

[0136]

[0137]

[0138] In the above examples, T is selected from O, S, Se or NPh; Ph represents phenyl.

[0139] Example 3

[0140] Preparation of Compound J536:

[0141]

[0142] 10.0 mmol of J506 (T = S) was mixed with 40 mL of glacial acetic acid, 1.0 mmol of ammonium molybdate and 5 mL of 30% hydrogen peroxide were added, and the mixture was stirred at room temperature for 15 hours. After concentration and drying under reduced pressure, 50 mL of saturated sodium bicarbonate aqueous solution was added, filtered, the filter cake was washed with water, and purified by silica gel column chromatography to obtain Compound J536, a white solid, with a yield of 98%, MS (TOF) m / z: 1083.3417; 1 HNMR (δ, CDCl3): 8.35 (2H, s); 8.09 - 8.01 (10H, m); 7.64 - 7.55 (8H, m); 7.51 - 7.43 (12H, m); 7.37 - 7.25 (14H, m).

[0143] Refer to the similar synthesis method above to prepare the compounds shown in Table 3 below:

[0144] Table 3

[0145] Reactant Product Yield J505 (T = S) J535 97％ J507 (T = S) J537 96％ J508 (T = S) J538 95％ J533 (T = S) J539 98％ J534 (T = S) J540 97％ J530 (T = S) J541 96％ J510 (T = S) J542 96％ J532 (T = S) J543 97％

[0146] Example 4

[0147] An OLED device, such as Figure 1As shown, the OLED device of this embodiment is a top-emitting light device, including a substrate 101, an anode layer 102 disposed on the substrate 101, a hole injection layer 103 disposed on the anode layer 102, a hole transport layer 104 disposed on the hole injection layer 103, an electron blocking layer 105 disposed on the hole transport layer 104, an organic light-emitting layer 106 disposed on the electron blocking layer 105, a hole blocking layer 107 disposed on the organic light-emitting layer 106, an electron transport layer 108 disposed on the hole blocking layer 107, an electron injection layer 109 disposed on the electron transport layer 108, a cathode 110 disposed on the electron injection layer 109, and a capping layer 111 above the cathode. The preparation method of the OLED device without the hole blocking layer 107 includes the following steps:

[0148] 1) Ultrasonically treat the glass substrate coated with the ITO conductive layer in a cleaning agent for 30 minutes, rinse it in deionized water, ultrasonically treat it in an acetone / ethanol mixed solvent for 30 minutes, bake it in a clean environment until completely dry, irradiate it with an ultraviolet light cleaning machine for 10 minutes, and bombard the surface with a low-energy cation beam.

[0149] 2) Place the above-treated ITO glass substrate in a vacuum chamber, evacuate to less than 1×10 -5 Pa, deposit metallic silver as the anode layer on the above ITO film, and the deposited film thickness is Continue to deposit compounds HI01 and F4TCNQ as the hole injection layer respectively. Among them, F4TCNQ is 3% of the mass of HI01, and the deposited film thickness is

[0150] 3) Continuously deposit compound HTM as the hole transport layer on the above hole injection layer, and the deposited film thickness is

[0151] 4) Continuously deposit compound EBL as the electron blocking layer on the above hole transport layer, and the deposited film thickness is

[0152] 5) Continuously deposit compound RH018 as the host material and RD011 as the doping material on the electron blocking layer. RD011 is 3% of the mass of compound RH018, which is used as the organic light-emitting layer of the device. The deposited film thickness of the obtained organic light-emitting layer is

[0153] 6) Continuously deposit a layer of LiQ and the compound of formula (I) of the present invention as the electron transport layer of the device on the organic light-emitting layer. Among them, the compound of formula (I) of the present invention is 50% of the mass of LiQ, and the deposited film thickness is

[0154] 7) Continuously deposit a layer of LiF as the electron injection layer above the electron transport layer, and the deposited film thickness is

[0155] 8) A transparent cathode layer of the device is formed by evaporating magnesium and silver on the electron injection layer, with the mass ratio of magnesium to silver being 1:10 and the evaporation film thickness being

[0156] 9) A CPL layer of the device is formed by evaporating a layer of CPD on the transparent cathode layer, with the evaporation film thickness being The OLED device provided by the present invention is obtained.

[0157] The chemical structures of the compounds used in the above Example 4 are as follows:

[0158]

[0159] Example 5

[0160] An organic electroluminescent device 200 has a structure as Figure 2 shown, which includes a substrate 201, an anode 202, a hole injection layer 203, a hole transport layer 204, a first light-emitting layer 205, an electron transport layer 206, a charge generation layer 207, a hole injection layer 208, a hole transport layer 209, a second light-emitting layer 210, an electron transport layer 211, an electron injection layer 212, and a cathode 213.

[0161] Comparative Example 1

[0162] Following the same steps as in Example 4, the compound of formula (I) of the present invention in step 6) was replaced with E01 to obtain Comparative Device 1;

[0163]

[0164] The following performance tests were conducted on the organic electroluminescent devices prepared in the above process:

[0165] The driving voltage, current efficiency, and lifespan of the organic electroluminescent devices prepared in Examples 4 and 5 and Comparative Example 1 were measured using a digital source meter and a luminance meter. Specifically, the voltage was increased at a rate of 0.1 V per second, and the voltage when the luminance of the organic electroluminescent device reached 1000 cd / m 2 was measured as the driving voltage, and the current density at this time was also measured; the ratio of luminance to current density was defined as the current efficiency; the LT95% lifespan test was as follows: using a luminance meter at a luminance of 1000 cd / m 2 while maintaining a constant current, the time taken for the luminance of the organic electroluminescent device to decay to 950 cd / m 2 was measured, with the unit being hours. The data listed in Table 4 are relative data compared to Comparative Device 1.

[0166] Table 4

[0167]

[0168]

[0169]

[0170] As can be seen from Table 4, the driving voltage of the element prepared from the heterocyclic compound of the present invention is lower than that of E01 at the same brightness, and the current efficiency is significantly improved, up to 1.26 times that of the comparison element, and the LT95% life of the element is greatly improved, indicating that the heterocyclic compound of the present invention is an electron transport layer material with excellent performance.

[0171] The difference between the compound E01 in comparative example 1 and the compound of the present invention is that the plane conjugation ability is weak after the introduction of three imidazole groups into the phenyl group, resulting in high voltage and low efficiency. However, the heterocyclic compound of the present invention has strong conjugation ability after the introduction of two imidazole groups into the ring of dibenzofuran, dibenzothiophene, etc., and the plane is enlarged, and its performance in molecular film formation and charge transmission is more excellent, and the charge transmission in the element is more balanced, so the element performance is significantly improved.

[0172] Although the present invention has been described in detail above with general descriptions and specific embodiments, it is obvious to those skilled in the art that some modifications or improvements may be made thereto based on the present invention. Therefore, these modifications or improvements made without departing from the spirit of the present invention all fall within the scope of protection claimed by the present invention.

Claims

1. A heterocyclic compound, characterized in that, The heterocyclic compound is selected from the following compounds: Wherein, T is selected from O, S, Se or NPh; Ph represents a phenyl group.

2. Use of the heterocyclic compound according to claim 1 in the preparation of an organic electroluminescent device.

3. An organic electroluminescent element, characterized in that, It includes: A first electrode, a second electrode, a capping layer, and one or more organic layers disposed between the first electrode and the second electrode; The material of at least one of the organic layer or the capping layer includes the heterocyclic compound according to claim 1.

4. The organic electroluminescent element according to claim 3, characterized in that, The organic layer includes a hole injection layer, a hole transport layer, a hole blocking layer, a light emitting layer, an electron transport layer, an electron injection layer or an electron blocking layer; the light emitting layer, the electron transport layer or the hole blocking layer includes the heterocyclic compound according to claim 1.

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