An organic electroluminescent device

Abstract

The present invention provides an organic electroluminescent device, and specifically relates to the technical field of organic electroluminescent. In order to solve the problem that the performance of the device is poor due to the poor performance of the covering layer material, the present invention provides an organic electroluminescent device, the covering layer material of the device can effectively improve the efficiency of light extraction inside the device, thereby increasing the luminous efficiency and service life of the device, because the covering layer compound has a larger rigid plane, a more regular symmetrical structure, and a lower interaction force between molecules, so that it has the advantages of a higher glass transition temperature, good thermal stability, and good film-forming properties; therefore, applying it to the organic electroluminescent device can effectively improve the luminous efficiency and performance of the device.

Description

Technical Field

[0001] The invention relates to the technical field of organic electroluminescence, and in particular to an organic electroluminescence device. Background Art

[0002] Organic Light-Emitting Diode (OLED) is an electroluminescent device with a multi-layer organic thin film structure. Compared with LCD, it has the advantages of being light, bright, low power consumption, fast response, high clarity, and high luminous efficiency. It can meet consumers' new demands for display technology and has a very broad development prospect.

[0003] According to the different light emission modes, OLED devices can be divided into top emission devices and bottom emission devices. Generally, top emission devices include organic layers such as hole injection layer, hole transport layer, hole blocking layer, electron injection layer, electron transport layer, electron blocking layer, light-emitting layer, and covering layer; generally, bottom emission devices include organic layers such as hole injection layer, hole transport layer, hole blocking layer, electron injection layer, electron transport layer, electron blocking layer, and light-emitting layer. The hole injection layer, hole transport layer, electron injection layer, and electron transport layer are used to realize the injection and transmission of carriers. The hole blocking layer is used to block holes from escaping to the cathode side, and the electron blocking layer is used to block electrons from transmitting to the anode side. The covering layer is generally located on the outside of the cathode to reduce the total reflection effect in the OLED device, thereby improving the light extraction efficiency.

[0004] The light extraction efficiency of top-emitting devices is higher than that of low-emitting devices. However, top-emitting devices also have certain disadvantages. For example, the light inside the device will be totally reflected at the interface between the ITO film and the glass substrate and the interface between the glass substrate and the air, and part of the light will be confined in the organic material film, the ITO film and the glass substrate in the form of a waveguide, which will reduce the light extraction efficiency when the light emitted from the light-emitting layer is emitted to the outside of the OLED device. Currently, the most effective way to improve the light extraction efficiency of the device is to add a covering layer on the surface of the device. However, the covering layer in the prior art has problems such as low refractive index, low glass transition temperature, poor thermal stability, and poor film-forming properties, and cannot effectively couple out the light inside the device, thereby reducing the luminous efficiency and service life of the device. Therefore, the development of a covering layer material with good performance is of great significance to the development of the OLED industry. Summary of the invention

[0005] In order to solve the above problems affecting the performance of organic electroluminescent devices, the present invention provides an organic electroluminescent device, which can significantly improve the luminous efficiency and service life of the organic electroluminescent device.

[0006] Specifically, the present invention provides an organic electroluminescent device, comprising an anode, a cathode, and an organic layer, wherein the organic layer comprises a covering layer, and the covering layer has a structure as shown in Formula I,

[0007]

[0008] In formula I, the Ar1 to Ar3 are identical or different to each other, at least one of which is selected from the group shown in formula II, and the rest are identical or different to each other and are selected from substituted or unsubstituted C6 to C30 aryl groups; the substituent is selected from any one of hydrogen, deuterium, substituted or unsubstituted C1 to C12 alkyl, substituted or unsubstituted C2 to C12 alkenyl, substituted or unsubstituted C3 to C12 cycloalkyl, and substituted or unsubstituted C6 to C30 aryl groups. In the case of being substituted by multiple substituents, the multiple substituents are identical or different to each other, or adjacent substituents may be connected to each other to form a substituted or unsubstituted ring;

[0009]

[0010] In formula II, the Ys are the same or different from each other and are selected from CH or N atoms, and the Ys contain at least one N atom;

[0011] The X1 is selected from any one of O, S or NR4, and the R4 is selected from any one of hydrogen, deuterium, substituted or unsubstituted C1-C12 alkyl, substituted or unsubstituted C2-C12 alkenyl, substituted or unsubstituted C3-C12 cycloalkyl, substituted or unsubstituted C6-C30 aryl, substituted or unsubstituted C3-C7 heteroaryl;

[0012] The R1 is selected from any one of hydrogen, deuterium, a halogen atom, a cyano group, a trifluoromethyl group, a substituted or unsubstituted C1-C12 alkyl group, a substituted or unsubstituted C2-C12 alkenyl group, a substituted or unsubstituted C3-C12 cycloalkyl group, a substituted or unsubstituted C6-C30 aryl group, and a substituted or unsubstituted C3-C7 heteroaryl group;

[0013] The m is selected from 0, 1, 2 or 3. When there are two or more R1, the two or more R1 are the same or different from each other, or two adjacent R1 can be connected to each other to form a substituted or unsubstituted ring;

[0014] The x are the same or different from each other and are selected from N atoms or CR2. When x is bonded to other groups, the x is selected from C atoms;

[0015] The R2 are the same or different from each other, and are selected from any one of hydrogen, deuterium, halogen atoms, cyano, trifluoromethyl, substituted or unsubstituted C1-C12 alkyl, substituted or unsubstituted C2-C12 alkenyl, substituted or unsubstituted C3-C12 cycloalkyl, substituted or unsubstituted C6-C30 aryl, substituted or unsubstituted C3-C30 heteroaryl. When there are two or more R2, the two or more R2 are the same or different from each other, or two adjacent R2 can be connected to each other to form a substituted or unsubstituted ring;

[0016] The L1 to L3 are the same as or different from each other and are selected from the following groups which are substituted or unsubstituted by a single bond, one or more deuterium, cyano, trifluoromethyl, halogen atoms, C1 to C12 alkyl, C3 to C12 cycloalkyl, C6 to C30 aryl, and any combination thereof: phenylene, biphenylene, naphthylene, pyridylene, pyrimidylene, benzocyclopentylene, and benzocyclohexylene.

[0017] Beneficial effects: The compound of formula I provided by the present invention is used as a covering layer compound, and its molecule has a larger rigid plane, a more regular symmetrical structure, and a lower interaction force between molecules, so that it has a higher glass transition temperature, good thermal stability, is not easy to decompose, and is not easy to crystallize in a thin film state and has good film-forming properties; at the same time, the introduction of N atoms in the molecule increases the refractive index of the covering layer compound, and its application in the covering layer of an organic electroluminescent device can improve the light extraction efficiency inside the device, reduce the total reflection phenomenon of light, thereby effectively improving the luminous efficiency and service life of the organic electroluminescent device. DETAILED DESCRIPTION

[0018] The following will be described clearly and completely in conjunction with the technical solutions of the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative work are within the scope of protection of the present invention.

[0019] In the compounds of the present invention, any atom not designated as a particular isotope is included as any stable isotope of that atom, and includes the atom in both its natural isotopic abundance and unnatural abundance.

[0020] In the present invention, "*" means a portion connecting to another substituent.

[0021] In the present invention, when the position of a substituent on a ring is not fixed, it means that it can be attached to any of the corresponding optional positions of the ring. For example, Can be expressed Etc. And so on.

[0022] Examples of the halogen atom described in the present invention may include fluorine, chlorine, bromine or iodine.

[0023] The alkyl group of the present invention refers to a monovalent group obtained by removing a hydrogen atom from an alkane molecule, which can be a straight chain alkyl group or a branched chain alkyl group, preferably having 1 to 12 carbon atoms, more preferably 1 to 8 carbon atoms, and particularly preferably 1 to 6 carbon atoms. The alkyl group can be substituted or unsubstituted. Specific examples may include methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, sec-butyl, tert-butyl, n-pentyl, isopentyl, n-hexyl, n-heptyl, n-octyl, n-nonyl, n-decyl, undecyl, dodecyl, etc., but are not limited thereto.

[0024] The alkenyl group of the present invention refers to a monovalent group obtained by removing a hydrogen atom from an olefin molecule, which can be a straight chain alkenyl group or a branched chain alkenyl group, preferably having 2 to 12 carbon atoms, more preferably 2 to 8 carbon atoms, and particularly preferably 2 to 6 carbon atoms. The alkenyl group can be substituted or unsubstituted. Specific examples may include vinyl, 1-propenyl, isopropenyl, butenyl, pentenyl, 3-methyl-1-butenyl, allyl, 1-phenylvinyl-1-yl, styryl, etc., but are not limited thereto.

[0025] The cycloalkyl group of the present invention refers to a monovalent group obtained by removing a hydrogen atom from a cyclic alkane molecule, preferably 3 to 12 carbon atoms, particularly preferably 3 to 6 carbon atoms. The cycloalkyl group may be substituted or unsubstituted. The cycloalkyl group includes cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, cycloheptyl, adamantyl, norbornyl, etc., but is not limited thereto.

[0026] The aryl group described in the present invention refers to a monovalent group obtained by removing a hydrogen atom from the aromatic carbon of the aromatic compound molecule, which can be a monocyclic aromatic group, a polycyclic aromatic group or a condensed aromatic group, preferably having 6 to 30 carbon atoms, more preferably 6 to 18 carbon atoms, and most preferably 6 to 12 carbon atoms. The aryl group can be substituted or unsubstituted. The monocyclic aromatic group refers to an aromatic group with only one aromatic ring in the molecule, for example, phenyl, etc., but not limited thereto; the polycyclic aromatic group refers to an aromatic group containing two or more independent aromatic rings in the molecule, for example, biphenyl, terphenyl, quaterphenyl, etc., but not limited thereto; the condensed aromatic group refers to an aromatic group containing two or more aromatic rings in the molecule and fused to each other by sharing two adjacent carbon atoms, for example, naphthyl, anthracenyl, phenanthrenyl, pyrenyl, perylenyl, The invention also includes, but is not limited to, 9,9-dimethylfluorenyl, 9,9-diphenylfluorenyl, 9-methyl-9-phenylfluorenyl, benzofluorenyl, 9,9'-spirobifluorenyl and the like.

[0027] The heteroaryl group of the present invention refers to a general term for a group in which one or more aromatic carbon atoms in an aromatic group are replaced by heteroatoms, wherein the heteroatoms include but are not limited to O, S, N, Si or P atoms, preferably having 2 to 30 carbon atoms, more preferably 2 to 20 carbon atoms, and further preferably having 3 to 12 carbon atoms. The attachment site of the heteroaryl group may be located on a ring-forming carbon atom or on a ring-forming heteroatom, and the heteroaryl group may be a monocyclic heteroaryl group, a polycyclic heteroaryl group or a condensed ring heteroaryl group. The heteroaryl group may be substituted or unsubstituted. The monocyclic heteroaryl includes pyridyl, pyrimidinyl, pyrazinyl, pyridazinyl, triazinyl, furanyl, thienyl, pyrrolyl, oxazolyl, thiazolyl, imidazolyl, etc., but not limited thereto; the polycyclic heteroaryl includes bipyridyl, bipyrimidinyl, phenylpyridinyl, phenylpyrimidinyl, etc., but not limited thereto; the condensed ring heteroaryl includes quinolyl, isoquinolyl, benzoquinolyl, benzoisoquinolyl, quinazolinyl, quinoxalinyl, benzoquinazolinyl, benzoquinoxalinyl, o-phenanthroline, naphthyridinyl , indolyl, benzothienyl, benzofuranyl, benzoxazolyl, benzimidazolyl, benzothiazolyl, N-heterobenzoxazolyl, N-heterobenzoimidazolyl, N-heterobenzothiazolyl, dibenzofuranyl, benzodibenzofuranyl, dibenzothienyl, benzodibenzothienyl, dibenzoxazolyl, dibenzimidazolyl, dibenzothiazolyl, carbazolyl, benzocarbazolyl, acridinyl, phenoxazinyl, phenothiazinyl, phenoxathiol, spirofluorenyloxanthryl, spirofluorenylthioanthryl, and the like, but are not limited thereto.

[0028] In the "substituted or unsubstituted" of the present invention, "unsubstituted" means that the hydrogen atom on the group is not replaced by any substituent; "substituted" means that at least one hydrogen atom on the group is replaced by a substituent, and the position of the substitution is not limited. When multiple hydrogen atoms are replaced by multiple substituents, the multiple substituents may be the same or different.

[0029] The substituents in the "substituted or unsubstituted" of the present invention may be the same or different from each other, and are selected from any one of deuterium, cyano, nitro, trifluoromethyl, halogen atoms, substituted or unsubstituted C1-C12 alkyl, substituted or unsubstituted C2-C12 alkenyl, substituted or unsubstituted C3-C12 cycloalkyl, substituted or unsubstituted C2-C12 heterocycloalkyl, substituted or unsubstituted C6-C30 aryl, substituted or unsubstituted C2-C30 heteroaryl, preferably deuterium, cyano , halogen atoms, trifluoromethyl, C1-C12 alkyl, C3-C12 cycloalkyl, C6-C30 aryl, C2-C30 heteroaryl, specific examples may include deuterium, fluorine, chlorine, bromine, iodine, cyano, trifluoromethyl, methyl, ethyl, n-propyl, isopropyl, n-butyl, tert-butyl, cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, cycloheptyl, adamantyl, norbornyl, phenyl, biphenyl, terphenyl, tolyl, pentadeuterated phenyl, naphthyl, anthracenyl, phenanthrenyl, pyrenyl, triphenylene, The invention also includes, but is not limited to, 1, 2, 4, 5-dimethyl-1, 2, 4-diphenyl ...

[0030] The term "connected to form a ring" used in the present invention refers to two groups connected to each other by a chemical bond and optionally aromatized. For example:

[0031]

[0032] In the present invention, the ring formed by connection can be an aromatic ring system, an aliphatic ring system or a ring system formed by the fusion of the two. The ring formed by connection can be a three-membered ring, a four-membered ring, a five-membered ring, a six-membered ring, a seven-membered ring or a condensed ring, such as benzene, naphthalene, indene, cyclopentene, cyclopentane, cyclopentane acene, cyclohexene, cyclohexane, cyclohexane acene, pyridine, pyrimidine, quinoline, isoquinoline, benzofuran, benzothiophene, dibenzofuran, dibenzothiophene, phenanthrene or pyrene, but is not limited thereto.

[0033] The present invention provides an organic electroluminescent device, comprising an anode, a cathode, and an organic layer, wherein the organic layer comprises a covering layer, and the covering layer has a structure as shown in Formula I.

[0034]

[0035] In formula I, the Ar1 to Ar3 are identical or different to each other, at least one of which is selected from the group shown in formula II, and the rest are identical or different to each other and are selected from substituted or unsubstituted C6 to C30 aryl groups; the substituent is selected from any one of hydrogen, deuterium, substituted or unsubstituted C1 to C12 alkyl, substituted or unsubstituted C2 to C12 alkenyl, substituted or unsubstituted C3 to C12 cycloalkyl, and substituted or unsubstituted C6 to C30 aryl groups. In the case of being substituted by multiple substituents, the multiple substituents are identical or different to each other, or adjacent substituents may be connected to each other to form a substituted or unsubstituted ring;

[0036]

[0037] In formula II, the Ys are the same as or different from each other and are selected from CH or N atoms, and the Ys contain at least one N atom;

[0038] The X1 is selected from any one of O, S or NR4, and the R4 is selected from any one of hydrogen, deuterium, substituted or unsubstituted C1-C12 alkyl, substituted or unsubstituted C2-C12 alkenyl, substituted or unsubstituted C3-C12 cycloalkyl, substituted or unsubstituted C6-C30 aryl, substituted or unsubstituted C3-C7 heteroaryl;

[0039] The R1 is selected from any one of hydrogen, deuterium, a halogen atom, a cyano group, a trifluoromethyl group, a substituted or unsubstituted C1-C12 alkyl group, a substituted or unsubstituted C2-C12 alkenyl group, a substituted or unsubstituted C3-C12 cycloalkyl group, a substituted or unsubstituted C6-C30 aryl group, and a substituted or unsubstituted C3-C7 heteroaryl group;

[0040] The m is selected from 0, 1, 2 or 3. When there are two or more R1, the two or more R1 are the same or different from each other, or two adjacent R1 can be connected to each other to form a substituted or unsubstituted ring;

[0041] The x are the same or different from each other and are selected from N atoms or CR2. When x is bonded to other groups, the x is selected from C atoms;

[0042] The R2 are the same or different from each other, and are selected from any one of hydrogen, deuterium, halogen atoms, cyano, trifluoromethyl, substituted or unsubstituted C1-C12 alkyl, substituted or unsubstituted C2-C12 alkenyl, substituted or unsubstituted C3-C12 cycloalkyl, substituted or unsubstituted C6-C30 aryl, substituted or unsubstituted C3-C30 heteroaryl. When there are two or more R2, the two or more R2 are the same or different from each other, or two adjacent R2 can be connected to each other to form a substituted or unsubstituted ring;

[0043] The L1 to L3 are the same as or different from each other and are selected from the following groups which are substituted or unsubstituted by a single bond, one or more deuterium, cyano, trifluoromethyl, halogen atoms, C1 to C12 alkyl, C3 to C12 cycloalkyl, C6 to C30 aryl, and any combination thereof: phenylene, biphenylene, naphthylene, pyridylene, pyrimidylene, benzocyclopentylene, and benzocyclohexylene.

[0044] Preferably, one of Ar1 to Ar3 is selected from the group shown in Formula II, and more preferably, Ar1, Ar2 or Ar3 is selected from the group shown in Formula II.

[0045] Preferably, two of Ar1 to Ar3 are selected from the group shown in Formula II, and more preferably, Ar1 and Ar2, Ar1 and Ar3, or Ar2 and Ar3 are selected from the group shown in Formula II.

[0046] Preferably, Ar1 to Ar3 are all selected from the group represented by formula II.

[0047] Preferably, the covering layer is selected from any one of the structures shown in Formula I-1 to Formula I-5;

[0048]

[0049] Preferably, the R2 are the same as or different from each other and are selected from any one of hydrogen, deuterium, a halogen atom, a cyano group, a trifluoromethyl group or the following groups which are substituted or unsubstituted by one or more deuteriums: methyl, ethyl, n-propyl, isopropyl, n-butyl, tert-butyl, cyclopropane, cyclobutane, cyclopentane, cyclohexane, cycloheptane, adamantyl, norbornane, phenyl, biphenyl, naphthyl, pyridyl, pyrimidinyl, N-heterobenzoxazolyl, N-heterobenzothiazolyl, N-heterobenzoimidazolyl.

[0050] Preferably, at least one Y in Formula II is selected from N atom.

[0051] Preferably, in the formula II, at least two Ys are selected from N atoms, or at least three Ys are selected from N atoms, or all four Ys are selected from N atoms.

[0052] Preferably, the formula II is selected from any one of the groups shown below;

[0053]

[0054] The R1s are the same as or different from each other and are selected from hydrogen, deuterium, a halogen atom, a cyano group, a trifluoromethyl group, or any one of the following groups which are substituted or unsubstituted by one or more deuterium groups: methyl, ethyl, n-propyl, isopropyl, n-butyl, tert-butyl, cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, cycloheptyl, adamantyl, norbornyl, phenyl, biphenyl, naphthyl, pyridyl, pyrimidyl;

[0055] The m1 is selected from 0, 1, 2 or 3, the m2 is selected from 0, 1 or 2, and the m3 is selected from 0 or 1.

[0056] Preferably, the formula II is selected from any one of the groups shown below;

[0057]

[0058]

[0059] The X1 are the same or different from each other and are selected from any one of O, S or NR4;

[0060] The R4 is selected from hydrogen, deuterium or the following groups which are substituted or unsubstituted by one or more deuteriums or C1-C12 alkyl groups: methyl, ethyl, n-propyl, isopropyl, n-butyl, tert-butyl, cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, cycloheptyl, adamantyl, norbornyl, phenyl, biphenyl, naphthyl, anthracenyl, phenanthryl, triphenylene, pyridyl and pyrimidinyl.

[0061] Preferably, the Ar1 to Ar3 are the same or different from each other, at least one of which is selected from the group shown in Formula II, and the others are the same or different from each other and are selected from any one of the following groups;

[0062]

[0063] The R a , R b , R c , R d , R e are the same as or different from each other and are selected from hydrogen, deuterium, a halogen atom, a cyano group, a trifluoromethyl group, or any one of the following groups which are substituted or unsubstituted by deuterium: a C1-C12 alkyl group, a C2-C12 alkenyl group, a C3-C12 cycloalkyl group, a C6-C30 aryl group, or R a , R b They may be connected to each other to form a substituted or unsubstituted ring, or R a , R b Can be directly bonded to any one of L1 to L3;

[0064] a1 is selected from 0, 1, 2, 3, 4 or 5, a2 is selected from 0, 1, 2, 3, 4, 5, 6 or 7, when there are two or more R c When two or more R c Same or different from each other, or two adjacent R c They can be connected to each other to form a substituted or unsubstituted ring; when there are two or more R d When two or more Rd Same or different from each other, or two adjacent R d They can be connected to each other to form a substituted or unsubstituted ring; when there are two or more R e When two or more R e Same or different from each other, or two adjacent R e They may be linked to each other to form a substituted or unsubstituted ring.

[0065] Preferably, the Ar1 to Ar3 are the same or different from each other, at least one of which is selected from the group shown in Formula II, and the others are the same or different from each other and are selected from any one of the following groups;

[0066]

[0067] The R3 are the same as or different from each other, and are selected from any one of hydrogen, deuterium, cyano, halogen atoms, or the following groups substituted or unsubstituted by one or more deuterium, C1-C12 alkyl groups: methyl, ethyl, n-propyl, isopropyl, n-butyl, tert-butyl, cyclopropane, cyclobutane, cyclopentane, cyclohexane, cycloheptane, adamantyl, norbornane, phenyl, biphenyl, naphthyl, anthracenyl, phenanthrenyl, triphenylene, pyrenyl; when there are two or more R3, the two or more R3 are the same as or different from each other, or two adjacent R3 can be connected to each other to form a substituted or unsubstituted benzene ring or naphthalene ring;

[0068] wherein n1 is selected from 0, 1, 2, 3, 4 or 5, n2 is selected from 0, 1, 2, 3 or 4, n3 is selected from 0, 1, 2, 3, 4, 5, 6 or 7, n4 is selected from 0, 1, 2, 3, 4, 5, 6, 7, 8 or 9, n5 is selected from 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10 or 11, and n6 is selected from 0, 1, 2, 3, 4, 5, 6, 7 or 8;

[0069] The R a , R b The same as or different from each other, any one of the following groups selected from hydrogen, deuterium or substituted or unsubstituted by one or more deuterium, C1-C12 alkyl: methyl, ethyl, n-propyl, isopropyl, n-butyl, tert-butyl, cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, cycloheptyl, adamantyl, norbornyl, phenyl, biphenyl, naphthyl;

[0070] The L a Any one of the following groups selected from a single bond, substituted by one or more deuterium, C1-C12 alkyl or unsubstituted: phenylene, biphenylene, naphthylene;

[0071] The Q is selected from a spiro ring structure, and the spiro ring structure is selected from any one of the following groups:

[0072]

[0073] The R5 are the same as or different from each other and are selected from any one of hydrogen, deuterium, cyano, halogen atoms or the following groups which are substituted or unsubstituted by one or more deuterium or C1-C12 alkyl groups: methyl, ethyl, n-propyl, isopropyl, n-butyl, tert-butyl, cyclopropane, cyclobutane, cyclopentane, cyclohexane, cycloheptane, adamantyl, norbornyl, phenyl, biphenyl, naphthyl;

[0074] The c1 is selected from 0, 1, 2, 3 or 4, the c2 is selected from 0, 1, 2, 3, 4, 5 or 6, the c3 is selected from 0, 1, 2, 3, 4, 5, 6, 7 or 8, the c4 is selected from 0, 1, 2, 3, 4, 5, 6, 7, 8, 9 or 10, the c5 is selected from 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11 or 12, and the c6 is selected from 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13 or 14.

[0075] Preferably, the Ar1 to Ar3 are the same or different from each other, at least one of which is selected from the group shown in Formula II, and the others are the same or different from each other and are selected from any one of the following groups;

[0076]

[0077]

[0078]

[0079] Preferably, the L1 to L3 are the same or different from each other and are selected from a single bond or any one of the following groups;

[0080]

[0081] Preferably, the Any one selected from the following groups;

[0082]

[0083]

[0084] Preferably, the covering layer is selected from any one of the structures shown below;

[0085]

[0086]

[0087]

[0088]

[0089]

[0090]

[0091]

[0092]

[0093]

[0094]

[0095]

[0096]

[0097]

[0098]

[0099]

[0100]

[0101]

[0102]

[0103]

[0104]

[0105]

[0106]

[0107]

[0108]

[0109]

[0110]

[0111]

[0112]

[0113]

[0114]

[0115]

[0116] Some specific structural forms of the compounds of formula I described in the present invention are listed above, but the present invention is not limited to these listed chemical structures. All compounds based on the structure shown in chemical formula I and having substituents as defined above should be included.

[0117] The present invention provides a method for preparing a compound represented by formula I, but the preparation method of the present invention is not limited thereto. The specific synthetic route is as follows:

[0118] Preparation of raw material a:

[0119]

[0120] Preparation of raw material b:

[0121]

[0122] 1. When Ar2--L2-* is the same as Ar3-L3-*;

[0123]

[0124] 2. Ar2-L2-* and Ar3-L3-* are different;

[0125]

[0126] Among them, X a are the same as or different from each other and are selected from any one of Cl, Br, and I; the definitions of Ar1 to Ar3, L1 to L3, and x are the same as those described above; the raw materials used in the above preparation route may be commercially available products or may be prepared by methods well known to those skilled in the art.

[0127] The organic electroluminescent device of the present invention comprises functional layers such as an anode, a hole transport region, a light-emitting layer, an electron transport region, a cathode, and a covering layer. Each functional layer can be composed of a single layer, a double layer, or a multilayer thin film, and each thin film can be composed of one material or two or more materials. However, the structure of the organic electroluminescent device is not limited thereto.

[0128] Preferably, the hole transport region described in the present invention comprises at least one layer of a hole injection layer, a hole transport layer, and an electron blocking layer.

[0129] Preferably, the hole transport layer of the present invention comprises a first hole transport layer and / or a second hole transport layer.

[0130] Preferably, the electron transport region described in the present invention comprises at least one layer of an electron injection layer, an electron transport layer, and a hole blocking layer; preferably, the electron transport region described in the present invention comprises at least one layer of an electron transport layer and a hole blocking layer; preferably, the electron transport region described in the present invention comprises a hole blocking layer.

[0131] Preferably, the electron transport layer of the present invention comprises a first electron transport layer and / or a second electron transport layer.

[0132] Preferably, the covering layer of the present invention comprises any one or more of the compounds of formula I of the present invention.

[0133] Preferably, the covering layer described in the present invention comprises a first covering layer and / or a second covering layer, and the first covering layer and / or the second covering layer comprises any one or more of the compounds of formula I described in the present invention.

[0134] The organic electroluminescent device of the present invention is usually formed on a substrate. The substrate may be any substrate that does not change when forming electrodes or organic layers, for example, glass, plastic, polymer film, silicon, etc.

[0135] The anode material of the present invention preferably uses a material with high functional function to improve hole injection efficiency. The anode material that can be used in the present invention is selected from the following: indium tin oxide (ITO), indium zinc oxide (IZO), tin oxide (SnO2), zinc oxide (ZnO) or any combination thereof, magnesium (Mg), silver (Ag), aluminum (Al), aluminum-lithium (Al-Li), calcium (Ca), magnesium-indium (Mg-In), magnesium-silver (Mg-Ag) or any combination thereof. The anode can have a single-layer structure or a multilayer structure including two or more layers, for example, the anode can have a single-layer structure of Al or a three-layer structure of ITO / Ag / ITO, but is not limited thereto.

[0136] The hole injection layer material of the present invention is preferably a material with good hole acceptance ability, and can be selected from any one or more of the following structures: metal porphyrin, oligothiophene, arylamine derivatives, perylene derivatives, hexanitrile hexaazatriphenylene compounds, phthalocyanine compounds, polycyano conjugated organic materials, quinacridone compounds, anthraquinone compounds, and conductive polymers based on polyaniline and polythiophene, etc., but not limited thereto.

[0137] The hole transport layer material of the present invention preferably has a material with high hole mobility, and can be selected from any one or more of the following structures: carbazole derivatives, triarylamine derivatives, diphenylene diamine derivatives, fluorene derivatives, stilbene derivatives, hexanitrile hexaazatriphenylene compounds, quinacridone compounds, anthraquinone compounds, polyaniline, polythiophene, polyvinylcarbazole, etc. Examples of the hole transport layer material include the following materials, N,N'-diphenyl-N,N'-di(3-methylphenyl)-1,1'-biphenyl-4,4'-diamine (TPD), N,N'-diphenyl-N,N'-(1-naphthyl)-1,1'-biphenyl-4,4'-diamine (NPB), 4-[1-[4-[di(4-methylphenyl)amino]phenyl]cyclohexyl]-N-(3-methylphenyl)-N-(4-methylphenyl)aniline (TAPC), N,N,N',N'-tetrakis(3-methylphenyl)-3,3'-dimethylbenzenediamine (HMTPD), etc., but are not limited thereto.

[0138] The light-emitting layer material of the present invention comprises a main material and a doping material. The main material of the light-emitting layer can be selected from 4,4'-di(9-carbazole)biphenyl (CBP), 9,10-di(2-naphthyl)anthracene (ADN), 4,4-di(9-carbazolyl)biphenyl (CPB), 9,9'-(1,3-phenyl)di-9H-carbazole (mCP), 4,4',4"-tri(carbazole-9-yl)triphenylamine (TCTA), 9,10-di(1-naphthyl)anthracene (α-AND), N,N'-di-(1-naphthyl)- N,N'-diphenyl-[1,1':4',1":4",1"'-quadrphenyl]-4,4"'-diamino (4PNPB), 1,3,5-tri(9-carbazolyl)benzene (TCP), etc. In addition to the above materials and their combinations, the main material of the light-emitting layer may also include other known materials suitable for the light-emitting layer, but is not limited thereto. The light-emitting layer doping materials of the present invention are divided into blue light-emitting materials, green light-emitting materials and red light-emitting materials. The light-emitting layer doping materials can be selected from (6-(4-(diphenylamino(phenyl) -N, N-diphenylpyrene-1-amine) (DPAP-DPPA), 2,5,8,11-tetra-tert-butylperylene (TBPe), 4,4'-bis[4-(diphenylamino)phenylvinyl]biphenyl (BDAVBi), 4,4'-bis[4-(di-p-tolylamino)phenylvinyl]biphenyl (DPAVBi), bis(2-hydroxyphenylpyridinium)beryllium (Bepp2), bis(4,6-difluorophenylpyridinium-C2,N)picolinyliridium (FIrpic), tris(2-phenylpyridinium)iridium (Ir( ppy)3), bis(2-phenylpyridine)iridium acetylacetonate (Ir(ppy)2(acac)), 9,10-bis[N-(p-tolyl)anilino]anthracene (TPA), 4-(dicyanomethylidene)-2-methyl-6-(4-dimethylaminophenylvinyl)-4H-pyran (DCM), tris[1-phenylisoquinoline-C2,N]iridium (III) (Ir(piq)3), bis(1-phenylisoquinoline)(acetylacetonate)iridium (Ir(piq)2(acac)), etc., but are not limited thereto.

[0139] The doping ratio of the host material and the guest material in the light-emitting layer of the present invention is determined according to the materials used. The amount of the doping material is preferably 0.1 to 70% by mass, more preferably 0.1 to 30% by mass, further preferably 1 to 30% by mass, further preferably 1 to 20% by mass, and particularly preferably 1 to 10% by mass.

[0140] The hole blocking layer material described in the present invention is preferably a material that can effectively block hole transmission and allow excitons to recombine in the light-emitting layer rather than in the electron transport layer. In addition to the nitrogen-containing heterocyclic derivatives provided by the present invention, any one or more of the following structures can be selected: phenanthroline derivatives, rare earth derivatives, imidazole derivatives, oxazole derivatives, oxadiazole derivatives, triazole derivatives, triazine derivatives, quinoline derivatives, diazine derivatives, azobenzene derivatives, anthrone derivatives, etc., but not limited thereto.

[0141] The electron transport layer material of the present invention is preferably a material with high electron mobility. It can be selected from any one or more of the following structures: 2,9-dimethyl-4,7-diphenyl-1,10-phenanthroline (BCP), 1,3,5-tris(N-phenyl-2-benzimidazole)benzene (TPBi), tris(8-hydroxyquinoline)aluminum(III) (Alq3), 8-hydroxyquinoline-lithium (Liq), di(2-methyl-8-hydroxyquinoline)(4-phenylphenol)aluminum(III) (BAlq), 3-(biphenyl-4-yl)-5-(4-tert-butylphenyl)-4-phenyl-4H-1,2,4-triazole (TAZ), 4,7-diphenyl-1,10-phenanthroline (Bphen), etc., but not limited thereto.

[0142] The electron injection layer material described in the present invention is preferably a material having a smaller difference in potential barrier with the adjacent organic layer material. Specific examples may include: alkali metal compounds (such as lithium oxide, lithium fluoride, cesium carbonate, cesium fluoride, 8-hydroxyquinoline cesium, 8-hydroxyquinoline aluminum), organic metal salts (metal acetates, metal benzoates or metal stearates), molybdenum trioxide, metal aluminum, etc., but are not limited thereto.

[0143] The cathode material of the present invention preferably uses a material with a low work function that can promote electron injection into the organic layer to reduce the electron injection barrier. It can be selected from any one or more of the following materials: Ag, Mg, Cu, Al, Pt, Pd, Au, Ni, Nd, Ir, Cr, Li, Ca, LiF / Ca, LiF / Al, Mo, Ti, compounds thereof, or mixtures thereof (e.g., a mixture of Ag and Mg), but is not limited thereto.

[0144] The covering layer of the present invention is provided on the outside of any one or more electrodes of the anode and the cathode to reduce the total reflection loss of light and improve the light extraction efficiency. It can be selected from any one or more of the following structures: arylamine derivatives, biscarbazole derivatives, benzimidazole derivatives, benzoxazole derivatives, benzothiazole derivatives, triazole derivatives, benzofuran derivatives, diamine derivatives, porphyrin derivatives, phthalocyanine derivatives, Alq3, TPBi or mixtures thereof, but not limited thereto. The compound of formula I of the present invention is preferred.

[0145] The present invention has no special limitation on the thickness of each organic layer of the organic electroluminescent device, and the thickness commonly used in the art can be adopted.

[0146] The organic electroluminescent device of the present invention can be manufactured by sequentially stacking the above-mentioned structures. The manufacturing method can use a known method such as a wet film forming method and a dry film forming method. Specific examples of the wet film forming method include various coating methods such as a spin coating method, a dipping method, a casting method, and an inkjet method. Specific examples of the dry film forming method include a vacuum evaporation method, a sputtering method, a plasma method, an ion plating method, etc., but are not limited thereto.

[0147] The organic light-emitting device of the present invention can be widely used in the fields of panel display, lighting source, flexible OLED, electronic paper, organic solar cell, organic photoreceptor or organic thin film transistor, signboard, signal lamp, etc.

[0148] By the following examples, the present invention is explained in more detail, but it is not intended to limit the present invention. On the basis of this description, those of ordinary skill in the art will be able to implement the present invention and prepare other compounds and devices according to the present invention within the entire disclosed range without paying creative work.

[0149] Preparation and characterization of compounds

[0150] Description of raw materials, reagents and characterization equipment:

[0151] The present invention has no particular limitation on the sources of the raw materials used in the following examples, and the raw materials may be commercially available products or prepared by methods well known to those skilled in the art.

[0152] Mass spectrometry was performed using a British Waters G2-Si quadrupole tandem time-of-flight high-resolution mass spectrometer, with chloroform as the solvent;

[0153] The elemental analysis used the Vario EL cube organic element analyzer from Elementar, Germany, with a sample mass of 5 to 10 mg;

[0154] Synthesis Example 1: Preparation of raw material a-378:

[0155]

[0156] Under nitrogen protection, raw material b'-378 (24.76g, 90.00mmol), biboronic acid pinacol ester (25.14g, 99.00mmol), KOAc (17.67g, 180.00mmol), Pd (dppf) Cl2 (1.32g, 1.80mmol) were added to 1,4-dioxane (400mL), and the mixed solution of the above reactants was heated to reflux for 4.5h; after the reaction, it was cooled to room temperature, distilled water was added, extracted with ethyl acetate, and the liquid was separated by standing, the organic layer was collected, dried with anhydrous magnesium sulfate, filtered, and the filtrate was concentrated by vacuum distillation. The obtained solid was recrystallized with toluene to obtain raw material a-378 (21.75g, yield 75%); HPLC purity ≧99.71%. Mass spectrum m / z: 322.1475 (theoretical value: 322.1489).

[0157] Synthesis Example 2: Preparation of raw material a-441:

[0158]

[0159] According to the same preparation method as the raw material a-378 in Synthesis Example 1, an equal mole of b'-378 was replaced by an equal mole of b-1 to obtain a raw material a-441 (22.04 g) with HPLC purity ≧99.84%. Mass spectrum m / z: 322.1476 (theoretical value: 322.1489).

[0160] Synthesis Example 3: Preparation of raw material a-510:

[0161]

[0162] According to the same preparation method as the raw material a-378 in Synthesis Example 1, an equal mole of b'-378 was replaced by an equal mole of b'-510 to obtain a raw material a-510 (19.95 g) with HPLC purity ≧99.75%. Mass spectrum m / z: 312.1116 (theoretical value: 312.1104).

[0163] Synthesis Example 4: Preparation of raw material a-512:

[0164]

[0165] According to the same preparation method as the raw material a-378 in Synthesis Example 1, an equal mole of b'-378 was replaced by an equal mole of b'-512 to obtain a raw material a-512 (18.40 g) with HPLC purity ≧99.79%. Mass spectrum m / z: 262.0964 (theoretical value: 262.0947).

[0166] Synthesis Example 5: Preparation of raw material a'-512:

[0167]

[0168] According to the same preparation method as the raw material a-378 in Synthesis Example 1, an equal mole of b'-378 was replaced by an equal mole of b"-512 to obtain raw material a'-512 (21.37 g) with HPLC purity ≧99.42%. Mass spectrum m / z: 339.1229 (theoretical value: 339.1213).

[0169] Synthesis Example 6: Preparation of raw material a-513:

[0170]

[0171] According to the same preparation method as the raw material a-378 in Synthesis Example 1, an equal mole of b'-378 was replaced by an equal mole of b'-513 to obtain a raw material a-513 (21.92 g) with HPLC purity ≧99.74%. Mass spectrum m / z: 338.1275 (theoretical value: 338.1260).

[0172] Synthesis Example 7: Preparation of raw material a-551:

[0173]

[0174] According to the same preparation method as the raw material a-378 in Synthesis Example 1, an equal mole of b'-378 was replaced by an equal mole of b-551 to obtain raw material a-551 (22.29 g) with HPLC purity ≧99.54%. Mass spectrum m / z: 339.1201 (theoretical value: 339.1213).

[0175] Synthesis Example 8: Preparation of raw material a-563:

[0176]

[0177] According to the same preparation method as the raw material a-378 in Synthesis Example 1, an equal amount of b'-378 was replaced by an equal amount of b'-563 to obtain a raw material a-563 (18.17 g) with HPLC purity ≧99.37%. Mass spectrum m / z: 262.0931 (theoretical value: 262.0947).

[0178] Synthesis Example 9: Preparation of raw material a-587:

[0179]

[0180] According to the same preparation method as the raw material a-378 in Synthesis Example 1, an equal mole of b'-378 was replaced by an equal mole of b'-587 to obtain a raw material a-587 (22.84 g) with HPLC purity ≧99.85%. Mass spectrum m / z: 321.1663 (theoretical value: 321.1649).

[0181] Synthesis Example 10: Preparation of raw material b-41:

[0182]

[0183] Preparation of intermediate M-41:

[0184] Under nitrogen protection, raw material m-41 (34.46g, 180.00mmol), biboric acid pinacol ester (50.28g, 198.00mmol), K2CO3 (74.63g, 540.00mmol), Pd(PPh3)4 (6.24g, 5.40mmol) were added to DMF (750mL), and the mixed solution of the above reactants was heated to reflux for 4h; after the reaction was completed, the reaction mixture was cooled to room temperature, distilled water was added, extracted with dichloromethane, and the liquid was separated by standing, the organic layer was collected and dried with anhydrous magnesium sulfate, filtered, and the filtrate was concentrated by vacuum distillation, and the obtained solid was recrystallized with ethyl acetate and dried to obtain intermediate M-41 (36.92g, yield 86%); HPLC purity ≧98.83%. Mass spectrum m / z: 238.0945 (theoretical value: 238.0932).

[0185] Preparation of raw material b-41:

[0186] Under nitrogen protection, raw material b'-41 (35.76g, 130.00mmol), intermediate M-41 (31.63g, 132.60mmol), K2CO3 (35.93g, 260.00mmol), Pd(PPh3)4 (3.00g, 2.60mmol) were added to 450mL toluene, 150mL ethanol, and 150mL water, and the mixed solution of the above reactants was heated to reflux for 3h; after the reaction was completed, it was cooled to room temperature and filtered to obtain a filter cake, and the filter cake was recrystallized with toluene / ethanol = 5:1 to obtain raw material b-41 (32.70g, yield 82%); HPLC purity ≧99.16%. Mass spectrum m / z: 306.0576 (theoretical value: 306.0560).

[0187] Synthesis Example 11: Preparation of raw material b-149:

[0188]

[0189] According to the same preparation method as the raw material b-41 in Synthesis Example 10, an equal amount of b'-41 was replaced by an equal amount of b'-149 to obtain raw material b-149 (25.92 g) with HPLC purity ≧99.58%. Mass spectrum m / z: 255.0183 (theoretical value: 255.0199).

[0190] Synthesis Example 12: Preparation of raw material b-215:

[0191]

[0192] According to the same preparation method as the raw material b-41 in Synthesis Example 10, equimolar m-41 and b'-41 were replaced by equimolar m-215 and b'-215, respectively, to obtain raw material b-215 (28.83 g), HPLC purity ≧99.42%. Mass spectrum m / z: 280.0419 (theoretical value: 280.0403).

[0193] Synthesis Example 13: Preparation of raw material b-235:

[0194]

[0195] According to the same preparation method as the raw material b-41 in Synthesis Example 10, an equal amount of b'-41 was replaced by an equal amount of b'-235 to obtain raw material b-235 (26.30 g) with HPLC purity ≧99.78%. Mass spectrum m / z: 246.0007 (theoretical value: 246.0018).

[0196] Synthesis Example 14: Preparation of raw material b-247:

[0197]

[0198] According to the same preparation method as the raw material b-41 in Synthesis Example 10, equimolar m-41 and b'-41 were replaced by equimolar m-247 and b'-247, respectively, to obtain raw material b-247 (26.08 g), HPLC purity ≧99.38%. Mass spectrum m / z: 246.9960 (theoretical value: 246.9971).

[0199] Synthesis Example 15: Preparation of raw material b-253:

[0200]

[0201] According to the same preparation method as the raw material b-41 in Synthesis Example 10, an equal mole of b'-41 was replaced by an equal mole of b'-253 to obtain raw material b-253 (27.05 g) with HPLC purity ≧99.55%. Mass spectrum m / z: 246.9987 (theoretical value: 246.9971).

[0202] Synthesis Example 16: Preparation of raw material b-698:

[0203]

[0204] According to the same preparation method as the raw material b-41 in Synthesis Example 10, equimolar m-41 and b'-41 were replaced by equimolar m-698 and b'-235, respectively, to obtain raw material b-698 (25.86 g), HPLC purity ≧99.31%. Mass spectrum m / z: 247.9937 (theoretical value: 247.9923).

[0205] Synthesis Example 17: Preparation of Compound 1:

[0206]

[0207] Preparation of intermediate A-1:

[0208] Under nitrogen protection, raw material g-1 (21.13 g, 65 mmol), raw material a-1 (39.99 g, 162.5 mmol), Pd (OAc) 2 (0.37 g, 1.63 mmol) were added to DMF (450 mL), the mixture was stirred, and then K3PO4 aqueous solution (41.39 g, 195 mmol) was added, and the mixture was heated to reflux for 10 hours. After the reaction was completed, it was cooled to room temperature, distilled water was added, extracted with dichloromethane, and the mixture was allowed to stand for separation. The organic layer was collected and dried over anhydrous magnesium sulfate, filtered, and the filtrate was concentrated by vacuum distillation. The temperature was lowered for crystallization, and the solid was filtered by suction. The obtained solid was recrystallized from ethyl acetate to obtain intermediate A-1 (19.67 g, 75%), HPLC purity ≧ 99.51%. Mass spectrum m / z: 403.1051 (theoretical value: 403.1069).

[0209] Preparation of compound 1:

[0210] Under nitrogen protection, intermediate A-1 (19.36 g, 48 mmol), b-1 (11.00 g, 40 mmol), sodium tert-butoxide (11.53 g, 120 mmol) were added to 300 ml of toluene, and Pd2(dba)3 (0.36 g, 0.40 mmol) and P(t-Bu)3 (1.60 mL of 0.5 M toluene solution, 0.80 mmol) were added under stirring. The mixed solution of the above reactants was heated to reflux for 12 h. After the reaction was completed, it was cooled to room temperature, distilled water was added, extracted with dichloromethane, allowed to stand and separated, the organic layer was collected, dried over anhydrous magnesium sulfate, filtered, and the filtrate was concentrated by distillation under reduced pressure. The temperature was lowered for crystallization, and suction was filtered. The obtained solid was recrystallized from toluene to obtain compound 1 (16.73 g, yield 70%), HPLC purity ≧99.96%. Mass spectrum m / z: 597.1562 (theoretical value: 597.1549). Theoretical element content (%) C 36 H 19 N7O3: C, 72.36; H, 3.20; N, 16.41. Measured element content (%): C, 72.33; H, 3.25; N, 16.45.

[0211] Synthesis Example 18: Preparation of Compound 41:

[0212]

[0213] According to the same preparation method as compound 1 in Synthesis Example 17, an equal mole of b-1 was replaced by an equal mole of b-41 to obtain compound 41 (18.32 g), HPLC purity ≧99.93%. Mass spectrum m / z: 673.1851 (theoretical value: 673.1862). Theoretical element content (%) C 42 H 23 N7O3: C, 74.88; H, 3.44; N, 14.55. Measured element content (%): C, 74.85; H, 3.49; N, 14.51.

[0214] Synthesis Example 19: Preparation of Compound 69:

[0215]

[0216] According to the same preparation method as compound 1 in Synthesis Example 17, equal moles of a-1 and b-1 were replaced by equal moles of a-69 and b-69, respectively, to obtain compound 69 (17.57 g), HPLC purity ≧99.95%. Mass spectrum m / z: 645.0876 (theoretical value: 645.0864). Theoretical element content (%) C 36 H 19N7S3: C, 66.96; H, 2.97; N, 15.18. Measured element content (%): C, 66.99; H, 2.94; N, 15.23.

[0217] Synthesis Example 20: Preparation of Compound 117:

[0218]

[0219] According to the same preparation method as compound 1 in Synthesis Example 17, an equal mole of a-1 was replaced by an equal mole of a-117 to obtain compound 117 (18.41 g), HPLC purity ≧99.97%. Mass spectrum m / z: 613.2169 (theoretical value: 613.2154). Theoretical element content (%) C 44 H 27 N3O: C, 86.11; H, 4.43; N, 6.85. Measured element content (%): C, 86.15; H, 4.40; N, 6.81.

[0220] Synthesis Example 21: Preparation of Compound 119:

[0221]

[0222] According to the same preparation method as compound 1 in Synthesis Example 17, equal moles of a-1 and b-1 were replaced by equal moles of a-119 and b-119, respectively, to obtain compound 119 (22.06 g), HPLC purity ≧99.92%. Mass spectrum m / z: 765.2765 (theoretical value: 765.2780). Theoretical element content (%) C 56 H 35 N3O: C, 87.82; H, 4.61; N, 5.49. Measured element content (%): C, 87.85; H, 4.65; N, 5.44.

[0223] Synthesis Example 22: Preparation of Compound 120:

[0224]

[0225] According to the same preparation method as compound 1 in Synthesis Example 17, equal moles of a-1 and b-1 were replaced by equal moles of a-120 and b-120, respectively, to obtain compound 120 (18.20 g), HPLC purity ≧99.95%. Mass spectrum m / z: 614.2123 (theoretical value: 614.2107). Theoretical element content (%) C 43 H 26N4O: C, 84.02; H, 4.26; N, 9.11. Measured element content (%): C, 84.05; H, 4.23; N, 9.16.

[0226] Synthesis Example 23: Preparation of Compound 130:

[0227]

[0228] According to the same preparation method as compound 1 in Synthesis Example 17, equimolar g-1 and a-1 were replaced by equimolar g-130 and a-117, respectively, to obtain compound 130 (16.86 g), HPLC purity ≧99.91%. Mass spectrum m / z: 619.2519 (theoretical value: 619.2531). Theoretical element content (%) C 44 H 21 D6N3O: C, 85.27; H, 5.37; N, 6.78. Measured element content (%): C, 85.29; H, 5.32; N, 6.74.

[0229] Synthesis Example 24: Preparation of Compound 149:

[0230]

[0231] According to the same preparation method as compound 1 in Synthesis Example 17, equal moles of a-1 and b-1 were replaced by equal moles of a-149 and b-149, respectively, to obtain compound 149 (20.69 g), HPLC purity ≧99.92%. Mass spectrum m / z: 738.2438 (theoretical value: 738.2420). Theoretical element content (%) C 53 H 30 N4O: C, 86.16; H, 4.09; N, 7.58. Measured element content (%): C, 86.19; H, 4.12; N, 7.56.

[0232] Synthesis Example 25: Preparation of Compound 190:

[0233]

[0234] Preparation of intermediate A1-190:

[0235] Under nitrogen protection, raw material g-190 (25.34 g, 90 mmol), raw material a-1 (26.58 g, 108 mmol), Pd (OAc) 2 (0.22 g, 0.97 mmol) were added to DMF (600 mL), the mixture was stirred, and then K3PO4 aqueous solution (28.66 g, 135 mmol) was added, and the mixture was heated to reflux for 8 hours. After the reaction was completed, it was cooled to room temperature, distilled water was added, extracted with dichloromethane, and the mixture was allowed to stand for separation. The organic layer was collected and dried over anhydrous magnesium sulfate, filtered, and the filtrate was concentrated by vacuum distillation. The temperature was lowered for crystallization, and the solid was filtered by suction. The obtained solid was recrystallized from ethyl acetate to obtain intermediate A1-190 (22.52 g, 78%), HPLC purity ≧99.61%. Mass spectrum m / z: 320.0455 (theoretical value: 320.0465).

[0236] Preparation of intermediate A-190:

[0237] Under nitrogen protection, raw material A1-1 (20.85 g, 65 mmol), raw material a-117 (21.60 g, 85 mmol), Pd(OAc)2 (0.17 g, 0.75 mmol) were added to DMF (450 mL), the mixture was stirred, and then K3PO4 aqueous solution (21.23 g, 100 mmol) was added, and the mixture was heated under reflux for 10 hours. After the reaction was completed, the mixture was cooled to room temperature, distilled water was added, extracted with dichloromethane, and the mixture was allowed to stand for separation. The organic layer was collected and dried over anhydrous magnesium sulfate, filtered, and the filtrate was concentrated by vacuum distillation. The temperature was lowered for crystallization, and the solid was filtered by suction. The obtained solid was recrystallized from toluene to obtain intermediate A-190 (19.57 g, 73%), HPLC purity ≧99.73%. Mass spectrum m / z: 412.1340 (theoretical value: 412.1324).

[0238] Preparation of compound 190:

[0239] Under nitrogen protection, intermediate A-190 (17.32 g, 42 mmol), b-190 (7.25 g, 35 mmol), sodium tert-butoxide (10.09 g, 105 mmol) were added to 300 ml of toluene, and Pd2(dba)3 (0.16 g, 0.18 mmol) and P(t-Bu)3 (0.80 mL of 0.5 M toluene solution, 0.35 mmol) were added under stirring. The mixed solution of the above reactants was heated to reflux for 12 h. After the reaction was completed, it was cooled to room temperature, distilled water was added, extracted with dichloromethane, allowed to stand and separated, the organic layer was collected, dried over anhydrous magnesium sulfate, filtered, and the filtrate was concentrated by distillation under reduced pressure. The temperature was lowered for crystallization, and suction was filtered. The obtained solid was recrystallized from toluene to obtain compound 190 (12.82 g, yield 68%), HPLC purity ≧99.93%. Mass spectrum m / z: 538.1783 (theoretical value: 538.1794). Theoretical element content (%) C 37 H 22 N4O: C, 82.51; H, 4.12; N, 10.40. Measured element content (%): C, 82.53; H, 4.16; N, 10.35.

[0240] Synthesis Example 26: Preparation of Compound 215:

[0241]

[0242] According to the same preparation method as compound 1 in Synthesis Example 17, equal moles of a-1 and b-1 were replaced by equal moles of a-215 and b-215, respectively, to obtain compound 215 (23.13 g), HPLC purity ≧99.92%. Mass spectrum m / z: 825.3576 (theoretical value: 825.3564). Theoretical element content (%) C 60 H 27 D 10 N3O: C, 87.24; H, 5.73; N, 5.09. Measured element content (%): C, 87.28; H, 5.70; N, 5.13.

[0243] Synthesis Example 27: Preparation of Compound 235:

[0244]

[0245] According to the same preparation method as compound 1 in Synthesis Example 17, equal moles of a-1 and b-1 were replaced by equal moles of a-120 and b-235, respectively, to obtain compound 235 (18.39 g), HPLC purity ≧99.95%. Mass spectrum m / z: 629.1913 (theoretical value: 629.1926). Theoretical element content (%) C 44 H 27N3S: C, 83.92; H, 4.32; N, 6.67. Measured element content (%): C, 83.95; H, 4.29; N, 6.60.

[0246] Synthesis Example 28: Preparation of Compound 247:

[0247]

[0248] According to the same preparation method as compound 1 in Synthesis Example 17, equal moles of a-1 and b-1 were replaced by equal moles of a-120 and b-247, respectively, to obtain compound 247 (17.66 g), HPLC purity ≧99.93%. Mass spectrum m / z: 630.1898 (theoretical value: 630.1878). Theoretical element content (%) C 43 H 26 N4S: C, 81.88; H, 4.15; N, 8.88. Measured element content (%): C, 81.86; H, 4.19; N, 8.90.

[0249] Synthesis Example 29: Preparation of Compound 253:

[0250]

[0251] According to the same preparation method as compound 1 in Synthesis Example 17, equimolar g-1, a-1, and b-1 were replaced with equimolar g-253, a-120, and b-253, respectively, to obtain compound 253 (18.79 g), HPLC purity ≧99.95%. Mass spectrum m / z: 680.2022 (theoretical value: 680.2035). Theoretical element content (%) C 47 H 28 N4S: C, 82.92; H, 4.15; N, 8.23. Measured element content (%): C, 82.95; H, 4.11; N, 8.25.

[0252] Synthesis Example 30: Preparation of Compound 258:

[0253]

[0254] According to the same preparation method as compound 1 in Synthesis Example 17, equal moles of a-1 and b-1 were replaced by equal moles of a-258 and b-235, respectively, to obtain compound 258 (22.21 g), HPLC purity ≧99.96%. Mass spectrum m / z: 781.2567 (theoretical value: 781.2552). Theoretical element content (%) C 56 H 35N3S: C, 86.01; H, 4.51; N, 5.37. Measured element content (%): C, 86.04; H, 4.48; N, 5.40.

[0255] Synthesis Example 31: Preparation of Compound 319:

[0256]

[0257] According to the same preparation method as compound 1 in Synthesis Example 17, b-1 was replaced with b-190 in an equal mole to obtain compound 319 (16.10 g), HPLC purity ≧99.97%. Mass spectrum m / z: 529.1525 (theoretical value: 529.1539). Theoretical element content (%) C 34 H 19 N5O2: C, 77.12; H, 3.62; N, 13.23. Measured element content (%): C, 77.15; H, 3.60; N, 13.27.

[0258] Synthesis Example 32: Preparation of Compound 358:

[0259]

[0260] According to the same preparation method as compound 1 in Synthesis Example 17, equal moles of a-1 and b-1 were replaced by equal moles of a-358 and b-358, respectively, to obtain compound 358 (15.51 g), HPLC purity ≧99.96%. Mass spectrum m / z: 538.1899 (theoretical value: 538.1883). Theoretical element content (%) C 32 H 10 D7N7O2: C, 71.36; H, 4.49; N, 18.21. Measured element content (%): C, 71.39; H, 4.51; N, 18.17.

[0261] Synthesis Example 33: Preparation of Compound 378:

[0262]

[0263] According to the same preparation method as compound 1 in Synthesis Example 17, equal moles of a-1 and b-1 were replaced by equal moles of a-378 and b-378, respectively, to obtain compound 378 (19.36 g), HPLC purity ≧99.94%. Mass spectrum m / z: 681.2175 (theoretical value: 681.2165). Theoretical element content (%) C 46 H 27N5O2: C, 81.04; H, 3.99; N, 10.27. Measured element content (%): C, 81.01; H, 3.93; N, 10.30.

[0264] Synthesis Example 34: Preparation of Compound 385:

[0265]

[0266] According to the same preparation method as compound 1 in Synthesis Example 17, equimolar g-1, a-1, and b-1 were replaced with equimolar g-385, a-385, and b-385, respectively, to obtain compound 385 (17.84 g), HPLC purity ≧99.92%. Mass spectrum m / z: 655.2001 (theoretical value: 655.2008). Theoretical element content (%) C 44 H 25 N5O2: C, 80.60; H, 3.84; N, 10.68. Measured element content (%): C, 80.57; H, 3.82; N, 10.70.

[0267] Synthesis Example 35: Preparation of Compound 399:

[0268]

[0269] According to the same preparation method as compound 1 in Synthesis Example 17, equal moles of a-1 and b-1 were replaced by equal moles of a-399 and b-399, respectively, to obtain compound 399 (18.65 g), HPLC purity ≧99.96%. Mass spectrum m / z: 605.1870 (theoretical value: 605.1852). Theoretical element content (%) C 40 H 23 N5O2: C, 79.33; H, 3.83; N, 11.56. Measured element content (%): C, 79.29; H, 3.80; N, 11.59.

[0270] Synthesis Example 36: Preparation of Compound 403:

[0271]

[0272] According to the same preparation method as compound 1 in Synthesis Example 17, equal moles of a-1 and b-1 were replaced by equal moles of a-399 and b-403, respectively, to obtain compound 403 (17.31 g), HPLC purity ≧99.91%. Mass spectrum m / z: 609.2116 (theoretical value: 609.2103). Theoretical element content (%) C 40 H 19D4N5O2: C, 78.80; H, 4.46; N, 11.49. Measured element content (%): C, 78.84; H, 4.43; N, 11.44.

[0273] Synthesis Example 37: Preparation of Compound 404:

[0274]

[0275] According to the same preparation method as compound 1 in Synthesis Example 17, equal moles of a-1 and b-1 were replaced by equal moles of a-399 and b-404, respectively, to obtain compound 404 (18.62 g), HPLC purity ≧99.95%. Mass spectrum m / z: 655.1989 (theoretical value: 655.2008). Theoretical element content (%) C 44 H 25 N5O2: C, 80.60; H, 3.84; N, 10.68. Measured element content (%): C, 80.57; H, 3.81; N, 10.70.

[0276] Synthesis Example 38: Preparation of Compound 441:

[0277]

[0278] According to the same preparation method as compound 1 in Synthesis Example 17, equal moles of a-1 and b-1 were replaced by equal moles of a-441 and b-378, respectively, to obtain compound 441 (20.45 g), HPLC purity ≧99.96%. Mass spectrum m / z: 681.2178 (theoretical value: 681.2165). Theoretical element content (%) C 46 H 27 N5O2: C, 81.04; H, 3.99; N, 10.27. Measured element content (%): C, 81.08; H, 3.96; N, 10.30.

[0279] Synthesis Example 39: Preparation of Compound 490:

[0280]

[0281] According to the same preparation method as compound 1 in Synthesis Example 17, equal moles of a-1 and b-1 were replaced by equal moles of a-69 and b-378, respectively, to obtain compound 490 (16.63 g), HPLC purity ≧99.93%. Mass spectrum m / z: 561.1096 (theoretical value: 561.1082). Theoretical element content (%) C 34 H 19N5S2: C, 72.71; H, 3.41; N, 12.47. Measured element content (%): C, 72.69; H, 3.37; N, 12.49.

[0282] Synthesis Example 40: Preparation of Compound 510:

[0283]

[0284] According to the same preparation method as compound 1 in Synthesis Example 17, equal moles of a-1 and b-1 were replaced by equal moles of a-510 and b-510, respectively, to obtain compound 510 (21.33 g), HPLC purity ≧99.92%. Mass spectrum m / z: 761.1692 (theoretical value: 761.1708). Theoretical element content (%) C 50 H 27 N5S2: C, 78.82; H, 3.57; N, 9.19. Measured element content (%): C, 78.85; H, 3.54; N, 9.23.

[0285] Synthesis Example 41: Preparation of Compound 512:

[0286]

[0287] According to the same preparation method as compound 190 in Synthesis Example 25, equimolar g-190, a-1, a-117, and b-190 were replaced with equimolar g-512, a-512, a'-512, and b-512, respectively, to obtain compound 512 (16.22 g) with HPLC purity ≧99.90%. Mass spectrum m / z: 712.1521 (theoretical value: 712.1504). Theoretical element content (%) C 45 H 24 N6S2: C, 75.82; H, 3.39; N, 11.79. Measured element content (%): C, 75.85; H, 3.41; N, 11.83.

[0288] Synthesis Example 42: Preparation of Compound 513:

[0289]

[0290] According to the same preparation method as compound 1 in Synthesis Example 17, equimolar g-1, a-1, and b-1 were replaced with equimolar g-513, a-513, and b-513, respectively, to obtain compound 513 (21.49 g) with HPLC purity ≧99.92%. Mass spectrum m / z: 813.2031 (theoretical value: 813.2021). Theoretical element content (%) C 54 H 31N5S2: C, 79.68; H, 3.84; N, 8.60. Measured element content (%): C, 79.71; H, 3.88; N, 8.56.

[0291] Synthesis Example 43: Preparation of Compound 551:

[0292]

[0293] According to the same preparation method as compound 1 in Synthesis Example 17, equal moles of a-1 and b-1 were replaced by equal moles of a-551 and b-551, respectively, to obtain compound 551 (21.08 g), HPLC purity ≧99.91%. Mass spectrum m / z: 774.2315 (theoretical value: 774.2334). Theoretical element content (%) C 48 H 18 D9N7S2: C, 74.39; H, 4.68; N, 12.65. Measured element content (%): C, 74.41; H, 4.72; N, 12.61.

[0294] Synthesis Example 44: Preparation of Compound 563:

[0295]

[0296] According to the same preparation method as compound 1 in Synthesis Example 17, equimolar g-1, a-1, and b-1 were replaced with equimolar g-563, a-563, and b-563, respectively, to obtain compound 563 (19.54 g), HPLC purity ≧99.93%. Mass spectrum m / z: 697.2097 (theoretical value: 697.2082). Theoretical element content (%) C 42 H 31 N7S2: C, 72.29; H, 4.48; N, 14.05. Measured element content (%): C, 72.32; H, 4.50; N, 14.10.

[0297] Synthesis Example 45: Preparation of Compound 573:

[0298]

[0299] According to the same preparation method as compound 190 in Synthesis Example 25, equimolar g-190, a-1, a-117, and b-190 were replaced by equimolar g-512, a-399, a-69, and b-573, respectively, to obtain compound 573 (16.61 g), HPLC purity ≧99.96%. Mass spectrum m / z: 697.1925 (theoretical value: 697.1936). Theoretical element content (%) C 46 H 27N5OS: C, 79.18; H, 3.90; N, 10.04. Measured element content (%): C, 79.20; H, 3.95; N, 10.02.

[0300] Synthesis Example 46: Preparation of Compound 587:

[0301]

[0302] According to the same preparation method as compound 1 in Synthesis Example 17, equal moles of a-1 and b-1 were replaced by equal moles of a-587 and b-587, respectively, to obtain compound 587 (18.87 g), HPLC purity ≧99.96%. Mass spectrum m / z: 693.2658 (theoretical value: 693.2641). Theoretical element content (%) C 47 H 31 N7: C, 81.36; H, 4.50; N, 14.13. Measured element content (%): C, 81.39; H, 4.47; N, 14.11.

[0303] Synthesis Example 47: Preparation of Compound 651:

[0304]

[0305] According to the same preparation method as compound 1 in Synthesis Example 17, equal moles of a-1 and b-1 were replaced by equal moles of a-651 and b-119, respectively, to obtain compound 651 (15.92 g), HPLC purity ≧99.97%. Mass spectrum m / z: 523.2451 (theoretical value: 523.2469). Theoretical element content (%) C 36 H 13 D 10 N3O: C, 82.57; H, 6.35; N, 8.02. Measured element content (%): C, 82.53; H, 6.39; N, 8.05.

[0306] Synthesis Example 48: Preparation of Compound 698:

[0307]

[0308] According to the same preparation method as compound 1 in Synthesis Example 17, equal moles of a-1 and b-1 were replaced by equal moles of a-698 and b-698, respectively, to obtain compound 698 (20.51 g), HPLC purity ≧99.93%. Mass spectrum m / z: 683.2158 (theoretical value: 683.2144). Theoretical element content (%) C 46 H 29N5S: C, 80.80; H, 4.27; N, 10.24. Measured element content (%): C, 80.77; H, 4.24; N, 10.29.

[0309] Synthesis Example 49: Preparation of Compound 730:

[0310]

[0311] According to the same preparation method as compound 1 in Synthesis Example 17, b-1 was replaced with b-730 in an equal mole to obtain compound 730 (16.82 g), HPLC purity ≧99.96%. Mass spectrum m / z: 560.2022 (theoretical value: 560.2009). Theoretical element content (%) C 36 H 16 D5N5O2: C, 77.13; H, 4.67; N, 12.49. Measured element content (%): C, 77.18; H, 4.63; N, 12.52.

[0312] Synthesis Example 50: Preparation of Compound 734:

[0313]

[0314] According to the same preparation method as compound 1 in Synthesis Example 17, b-1 was replaced with b-734 in an equal mole to obtain compound 734 (17.56 g), HPLC purity ≧99.94%. Mass spectrum m / z: 645.2147 (theoretical value: 645.2165). Theoretical element content (%) C 43 H 27 N5O2: C, 79.98; H, 4.21; N, 10.85. Measured element content (%): C, 79.95; H, 4.18; N, 10.83.

[0315] Synthesis Example 51: Preparation of Compound 761:

[0316]

[0317] According to the same preparation method as compound 190 in Synthesis Example 25, equimolar g-190, a-1, a-117, and b-190 were replaced with equimolar g-512, a-69, a-761, and b-761, respectively, to obtain compound 761 (16.27 g), HPLC purity ≧99.91%. Mass spectrum m / z: 749.2854 (theoretical value: 749.2865). Theoretical element content (%) C 53 H 39N3S: C, 84.88; H, 5.24; N, 5.60. Measured element content (%): C, 84.90; H, 5.21; N, 5.57.

[0318] [Device Example 1]

[0319] First, the ITO / Ag / ITO substrate was cleaned three times in distilled water and ultrasonically washed for 15 minutes. After the distilled water cleaning, it was ultrasonically washed with isopropanol, acetone, methanol and other solvents in sequence and then dried at 120°C.

[0320] By using a vacuum evaporation method, HAT-CN with a thickness of 30 nm is evaporated on a cleaned ITO / Ag / ITO substrate as a hole injection layer material; NPB with a thickness of 70 nm is evaporated on the hole injection layer as a hole transport layer material; TCP:Ir(ppy)2(acac)=92:8 (mass ratio) is evaporated on the hole transport layer as a light-emitting layer with a thickness of 40 nm; TPBi and Liq (doping mass ratio of 1:1) are evaporated on the light-emitting layer as electron transport layer materials with a thickness of 30 nm; LiF is evaporated on the electron transport layer as an electron injection layer with a thickness of 1.0 nm; then Mg:Ag=1:9 (mass ratio of 1:1) is evaporated on the electron injection layer as a cathode with a thickness of 12 nm; then compound 1 is evaporated on the cathode as a covering layer with a thickness of 70 nm, thereby preparing an organic electroluminescent device.

[0321]

[0322] [Device Example 2-35]

[0323] Compound 41, compound 69, compound 117, compound 119, compound 120, compound 130, compound 149, compound 190, compound 215, compound 235, compound 247, compound 253, compound 258, compound 319, compound 358, compound 378, compound 385, compound 399, compound 403, compound 404, compound 441, compound 490, compound 510, compound 512, compound 513, compound 551, compound 563, compound 573, compound 587, compound 651, compound 698, compound 730, compound 734, and compound 761 of the present invention are used to replace compound 1 in device example 1 as a covering layer, except that an organic electroluminescent device is prepared by the same preparation method as device example 1.

[0324] [Comparative Device Examples 1-3]

[0325] Organic electroluminescent devices were prepared by the same preparation method as in Device Example 1 except that Comparative Compound 1, Comparative Compound 2 and Comparative Compound 3 were used to replace Compound 1 in Device Example 1 as the covering layer.

[0326] The test software, computer, K2400 digital source meter produced by Keithley Company of the United States and PR788 spectrum scanning luminance meter produced by PhotoResearch Company of the United States are combined into a joint IVL test system to test the luminous efficiency of organic electroluminescent devices. The life test adopts the M6000 OLED life test system of McScience Company. The test environment is atmospheric environment and the temperature is room temperature.

[0327] The test results of the luminescent characteristics of the organic electroluminescent devices obtained in device embodiments 1 to 34 of the present invention and comparative embodiments 1 to 3 are shown in Table 1 below.

[0328]

[0329]

[0330] According to the data results in Table 1, it can be seen that the application of the covering layer compound of the present invention in an organic electroluminescent device as a covering layer material can effectively improve the light extraction efficiency of the device compared with the comparative device embodiments 1-3, thereby increasing the luminous efficiency and service life of the organic electroluminescent device.

[0331] It should be noted that the present invention is particularly described using individual embodiments. However, without departing from the principles of the present invention, a person skilled in the art may make various improvements in form or detail to the present invention, and these improvements also fall within the scope of protection of the present invention.

Claims

1. An organic electroluminescent device, comprising an anode, a cathode, and an organic layer, wherein the organic layer comprises a covering layer, characterized in that: The covering layer has a structure as shown in Formula I, In formula I, the Ar1 to Ar3 are the same or different from each other, and at least one of them is selected from the group shown in formula II. When Ar1 is not selected from the group shown in formula II, it is selected from any one of the following groups; When Ar2 to Ar3 are not selected from the group shown in formula II, they are the same as or different from each other and are selected from any one of the following groups; The R3 groups are the same or different from each other and are selected from any one of hydrogen, deuterium or the following groups which are substituted or unsubstituted by one or more deuterium groups: methyl, ethyl, n-propyl, isopropyl, n-butyl, tert-butyl, adamantyl and phenyl. When there are two or more R3 groups, the two or more R3 groups are the same or different from each other. The R 3a are the same as or different from each other and are selected from any one of the following groups which are substituted or unsubstituted by one or more deuterium groups: methyl, ethyl, n-propyl, isopropyl, n-butyl, tert-butyl, phenyl; when there are two or more R 3a When two or more R 3a Same or different from each other, or two adjacent R 3a They can be connected to each other to form substituted or unsubstituted benzene rings; The R 3b are the same as or different from each other and are selected from hydrogen and deuterium; when there are two or more R 3b When two or more R 3b the same as or different from one another; The n1 is selected from 0, 1, 2, 3, 4 or 5, the n2 is selected from 0, 1, 2, 3 or 4, the n3 is selected from 0, 1, 2, 3, 4, 5, 6 or 7, the n4 is selected from 0, 1, 2, 3, 4, 5, 6, 7, 8 or 9, and the n5 is selected from 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10 or 11; The R a , R b The same as or different from each other, selected from the following groups substituted or unsubstituted by one or more deuteriums: methyl, ethyl, n-propyl, isopropyl, n-butyl, tert-butyl, and the following groups substituted or unsubstituted by one or more deuteriums and C1-C6 alkyls: any one of phenyl, biphenyl and naphthyl; The formula II is selected from any one of the groups shown below; The X1 are the same or different from each other and are selected from any one of O, S or NR4; The R4 is selected from the following groups which are substituted or unsubstituted by one or more deuterium groups: phenyl, biphenyl, naphthyl; Said Any one selected from the following groups; The L1 is selected from any one of the following groups which are single bonds, substituted by one or more deuteriums or unsubstituted: phenylene, biphenylene, naphthylene, pyridylene, pyrimidylene; The L2 to L3 are the same as or different from each other and are selected from any one of the following groups which are single bonds, substituted by one or more deuteriums or unsubstituted: phenylene, naphthylene, and pyridylene.

2. An organic electroluminescent device according to claim 1, characterized in that: The covering layer is selected from any one of the structures shown in Formula I-1 to Formula I-5; 3. The organic electroluminescent device according to claim 1, characterized in that: The formula II is selected from any one of the groups shown below; 4. The organic electroluminescent device according to claim 1, characterized in that: The R3 are the same or different from each other and are selected from any one of hydrogen, deuterium or the following groups which are substituted or unsubstituted by one or more deuteriums: methyl, ethyl, isopropyl, tert-butyl; when there are two or more R3, the two or more R3 are the same or different from each other; The R 3a are the same as or different from each other and are selected from any one of the following groups which are hydrogen, deuterium or substituted or unsubstituted by one or more deuterium groups: methyl, ethyl, isopropyl, tert-butyl; The R a , R b The same as or different from each other, and selected from any one of the following groups which may be substituted by one or more deuteriums: methyl, and the following groups which may be substituted by one or more deuteriums: phenyl.

5. The organic electroluminescent device according to claim 1, characterized in that: When Ar1 is not selected from the group shown in formula II, it is selected from any one of the following groups; When Ar2 to Ar3 are not selected from the group shown in formula II, they are selected from any one of the following groups; 6. The organic electroluminescent device according to claim 1, characterized in that: The L1 is selected from a single bond or any one of the following groups; The L2 to L3 are the same or different from each other and are selected from a single bond or any one of the following groups; 7. The organic electroluminescent device according to claim 1, characterized in that: Said Any one selected from the following groups; 8. An organic electroluminescent device, comprising an anode, a cathode, and an organic layer, wherein the organic layer comprises a covering layer, characterized in that: The covering layer is selected from any one of the structures shown below;

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