Triarylamine compound and organic electroluminescent device

Abstract

The invention relates to the field of organic light-emitting diode preparation, in particular to a triarylamine compound and an organic light-emitting device. Wherein the triarylamine compound has a structure as shown in a formula (a): # imgabs0 #, and a device adopting the compound provided by the invention has long service life.

Description

Technical Field

[0001] The invention relates to the field of organic light emitting diode preparation, in particular to a triarylamine compound and an organic electroluminescent device. Background Art

[0002] OLED, or organic light-emitting diode, has the advantages of high brightness, high contrast, and the ability to design transparent displays, while also having low production costs.

[0003] In the prior art, the main purpose of adding an electron blocking layer is, on the one hand, to block the uncombined electrons in the light-emitting layer and transfer holes to the light-emitting layer, and on the other hand, to adjust the optical microcavity of the device by designing the thickness of this layer. These two aspects mainly improve the luminous efficiency of the device. However, the electron blocking layer is also attacked by high-energy excitons in the light-emitting layer. Therefore, in order to obtain an OLED device with a long service life, the electron blocking layer material needs to have a strong ability to resist excitons.

[0004] Triarylamine compounds containing aromatic substituted dimethylfluorenyl and / or dibenzofuran have good hole transport properties and electron blocking properties and are widely used in auxiliary layers such as hole transport layers or electron blocking layers. However, the service life of the device still needs to be further improved. Summary of the invention

[0005] In view of the above-mentioned shortcomings of the prior art, the object of the present invention is to provide a triarylamine compound and an organic electroluminescent device. The device using the compound provided by the present invention has a long service life.

[0006] The present invention provides a triarylamine compound, wherein the triarylamine compound has a structure as shown in formula (a):

[0007]

[0008] Wherein, Z is selected from O, C(CH 3 ) 2 or C(CD 3 ) 2 .

[0009] R 1 To R 3 are the same as or different from each other and are independently selected from hydrogen, deuterium or a group described by formula (b):

[0010]

[0011] Preferably, the group described in formula (b) is selected from the following:

[0012]

[0013] Among them, R 4 ,R 5 As a bonding site, it bonds to formula (a);

[0014] Formula (a) satisfies the following conditions: R 1 ,R 2 ,R 3 There is only one group selected from the group described in formula (b).

[0015] Ar 1 ,Ar 2 Each is independently selected from a substituted or unsubstituted aryl group having 6 to 24 carbon atoms and a substituted or unsubstituted heteroaryl group having 3 to 24 carbon atoms.

[0016] Optionally, the hydrogen atom at any position in formula (a) and / or formula (b) may be replaced by deuterium.

[0017] The present invention further provides a functional layer, which comprises the aforementioned triarylamine compound of the present invention.

[0018] The present invention also provides use of the aforementioned triarylamine compound of the present invention and / or the aforementioned functional layer of the present invention in an organic electroluminescent device.

[0019] The present invention also provides an organic electroluminescent device, which comprises a first electrode, a second electrode and a functional layer as described above in the present invention, wherein the functional layer is at least one of a hole injection layer, a hole transport layer, an electron blocking layer, a light-emitting layer, an electron injection layer or an electron transport layer.

[0020] The present invention also provides a display or lighting device, which comprises the organic electroluminescent device as described above in the present invention.

[0021] By adopting the above technical solution, the beneficial effects of the present invention are:

[0022] 1. The 2-position of the fluorenyl group or the 3-position of the dibenzofuranyl group is connected to an arylamine group, which has better conjugation than the bonding at other positions, ensuring that the molecule has good hole migration characteristics; at the same time, the aryl group is introduced at the asymmetric position of the fluorenyl group or the dibenzofuranyl group. On the one hand, the aryl group has a certain steric hindrance effect, which helps to form an amorphous film during the device preparation process; on the other hand, the molecule has a higher triplet energy level, so when it is used as an electron blocking layer, it is beneficial to resist electrons and high-energy excitons, making it difficult to lose from the light-emitting layer, ensuring the efficiency of the device; and when the aryl group is a substituent group described in formula (b), dibenzofuran-1-yl and dibenzofuran-4-yl are both substituents with certain electron-withdrawing properties. As an electron blocking layer, electrons or high-energy excitons are more inclined to attack the fragments of the molecule with electron-withdrawing properties, so that the electrons or high-energy excitons attack away from the CN bond, and the stability of the triarylamine structure is guaranteed.

[0023] 2. In particular, when the aromatic group is a substituent group as described in formula (b1), that is, a phenyl group is further introduced at the 3'-position of the dibenzofuranyl group, so that the conjugation of the dibenzofuranyl group is further extended. When electrons or high-energy excitons attack, the charge or energy they carry can be distributed in a larger conjugated plane, thereby further improving the stability of the molecule and thus improving the life of the device.

[0024] 3. In particular, when the 2-position of the fluorenyl group is connected to an arylamine group and an aryl group is introduced at an asymmetric position, it has a more unexpected effect (mainly an improvement in efficiency) compared to the bonding at other positions. Even compared to the "3-position of the dibenzofuranyl group connected to an arylamine group", it has an outstanding effect. The reason is that the dimethylfluorenyl group containing an alkyl group has a certain electron-donating property, while dibenzofuran has a certain electron-withdrawing property. The fluorenyl group and the dibenzofuranyl group are bonded to each other to form a strong intramolecular interaction, which is particularly beneficial to the transport of carriers, so the device as a whole has a higher efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 Schematic diagram of the structure of an organic electroluminescent device in a green light device embodiment.

[0026] Figure 2 Schematic diagram of the structure of an organic electroluminescent device in a blue light device embodiment.

[0027] In the figure:

[0028] 101 Base

[0029] 102 first electrode

[0030] 103 Hole injection layer

[0031] 104 Hole transport layer

[0032] 105 Electron blocking layer

[0033] 106 Luminescent Layer

[0034] 107 Hole blocking layer

[0035] 108 Electron transport layer

[0036] 109 second electrode

[0037] 110 Covering DETAILED DESCRIPTION

[0038] Hereinafter, the embodiments of the triarylamine compound and the organic electroluminescent device provided by the present invention will be described in detail.

[0039] The inventors of the present proposal surprisingly found that a compound having a specific structure has a long service life, thereby completing the present invention.

[0040] First of all, the position numbers of dibenzofuranyl and fluorenyl are

[0041] Specifically: the 2-position of the fluorenyl group or the 3-position of the dibenzofuranyl group is connected to an aromatic amine group, which has better conjugation than bonding at other positions, ensuring that the molecule has good hole migration properties. More specifically, the aromatic group is introduced at the asymmetric position of the fluorenyl group or the dibenzofuranyl group. On the one hand, the aromatic group has a certain steric hindrance effect, which helps to form an amorphous film during the device preparation process; on the other hand, the molecule has a higher triplet energy level, so when used as an electron blocking layer, it is helpful to resist electrons and high-energy excitons, making it difficult for them to leak from the light-emitting layer, thereby ensuring the efficiency of the device. In particular, when the 2-position of the fluorenyl group is connected to an arylamine group and an aromatic group is introduced at an asymmetric position, it has a more unexpected effect compared to the bonding at other positions, and even has an outstanding effect compared to the "3-position of the dibenzofuranyl group connected to an arylamine group". The reason is that the dimethylfluorenyl group containing an alkyl group has a certain electron-donating property, while dibenzofuran has a certain electron-withdrawing property. The fluorenyl group and the dibenzofuranyl group are bonded to each other to form a strong intramolecular interaction, which is particularly beneficial to the transport of carriers, so the device as a whole has a higher efficiency.

[0042] The aromatic group introduced at the asymmetric position of the fluorenyl or dibenzofuranyl is 3'-phenyl-dibenzofuran-1-yl or 3'-phenyl-dibenzofuran-4-yl. Among them, dibenzofuran-1-yl and dibenzofuran-4-yl are substituents with certain electron-withdrawing properties. As an electron blocking layer, electrons or high-energy excitons are more inclined to attack the fragments of the molecule with electron-withdrawing properties, so that the electrons or high-energy excitons attack away from the CN bond, and the stability of the triarylamine structure is guaranteed; further, phenyl is further introduced at the 3'-position of the above-mentioned dibenzofuranyl, so that the conjugation of the dibenzofuranyl is further extended. When the electrons or high-energy excitons attack, the charge or energy they carry can be shared in a larger conjugated plane, so that the stability of the molecule is further improved, and the life of the device is improved.

[0043] Hereinafter, the present application will be described in detail. However, the following description is intended to explain the present invention and is not intended to limit the scope of the present invention in any way.

[0044] In the present application, the term "alkyl group having 1 to 6 carbon atoms" means a straight or branched alkyl group having 1 to 6 carbon atoms constituting the chain, and the number of carbon atoms is further preferably 1 to 6, and more preferably 1 to 4. The above-mentioned alkyl group may include methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, tert-butyl, sec-butyl, 1-methyl-butyl, 1-ethyl-butyl, n-pentyl, isopentyl, neopentyl, tert-pentyl, n-hexyl, 1-methylpentyl, 2-methylpentyl, 4-methyl-2-pentyl, 3,3-dimethylbutyl, 2-ethylbutyl, and the like.

[0045] Hereinafter, throughout the text, the deuterated in the deuterated alkyl mentioned refers to any number of hydrogens in any position being replaced by deuterium.

[0046] In the present application, the term "cycloalkyl having 3 to 10 carbon atoms" means a mono- or polycyclic hydrocarbon having 3 to 10 ring skeleton carbon atoms, and the above cycloalkyl may include cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, cyclopentylmethyl, cyclohexylmethyl, etc.

[0047] Hereinafter, throughout the text, the deuterated in the deuterated cycloalkyl mentioned refers to any number of hydrogen atoms at any position being replaced by deuterium.

[0048] In the present application, the term "substituted or unsubstituted (sub)aryl having 6 to 24 carbon atoms" means a monocyclic or condensed ring group derived from an aromatic hydrocarbon having 6 to 24 ring skeleton carbon atoms, and may be partially saturated and may contain a spiro structure. Examples of aryl groups specifically include phenyl, methylphenyl, biphenyl, naphthyl, fluorenyl, phenylfluorenyl, dimethylfluorenyl, diphenylfluorenyl, etc.

[0049] In the present application, the term "substituted or unsubstituted (sub)heteroaryl having 3 to 24 carbon atoms" refers to an aryl having a ring skeleton atom, wherein the ring skeleton atom includes at least one heteroatom selected from the group consisting of B, N, O, S, Si, P, Se and Ge, preferably at least one heteroatom selected from N, O and S, and the number of heteroatoms in the heteroaryl is preferably 1 to 4. The above heteroaryl group may be a monocyclic ring or a condensed ring condensed with at least one benzene ring; and may be partially saturated. In addition, herein, the above heteroaryl group may be a heteroaryl group formed by connecting at least one heteroaryl group or aryl group to a heteroaryl group via one or more single bonds. Examples of heteroaryl groups specifically include monocyclic heteroaryl groups, including furanyl, thienyl, pyrrolyl, imidazolyl, pyrazolyl, thiazolyl, thiadiazolyl, isothiazolyl, isoxazolyl, oxazolyl, oxadiazolyl, triazinyl, tetrazinyl, triazolyl, tetrazolyl, furazanyl, pyridyl, pyrazinyl, pyrimidinyl, pyridazinyl, etc., and fused ring heteroaryl groups, including benzofuranyl, benzothienyl, isobenzofuranyl, dibenzofuranyl, dibenzothienyl, dibenzoselenophene, etc.

[0050] In addition, the term "substituted" in the expression "substituted or unsubstituted" means that a hydrogen atom in a functional group is replaced by another atom or functional group (i.e., a substituent). Preferably, in the present application, the substituted substituent includes, but is not limited to, each independently selected from deuterium, a halogen group, a cyano group, an alkyl group having 1 to 10 carbon atoms, a deuterated alkyl group having 1 to 10 carbon atoms, a cycloalkyl group having 3 to 10 carbon atoms, an alkoxy group having 1 to 10 carbon atoms, an aryl group having 6 to 20 carbon atoms, an alkyl-substituted aryl group having 6 to 20 carbon atoms, or a heteroaryl group having 3 to 20 carbon atoms. Further options include deuterium, alkyl having 1 to 6 carbon atoms, deuterated alkyl having 1 to 6 carbon atoms, cycloalkyl having 3 to 10 carbon atoms, phenyl, naphthyl, phenanthryl, methylphenyl, tert-butylphenyl, 9,9-dimethylfluorenyl, 9,9-diphenylfluorenyl, dibenzofuranyl, dibenzothiophenyl, benzonaphthothiophenyl, benzonaphthofuranyl, etc.

[0051] Hereinafter, the triarylamine compound of the present invention will be described.

[0052] The present invention provides a triarylamine compound having a structure as shown in formula (a):

[0053]

[0054] In the present invention, Z is selected from O, C(CH 3 ) 2 or C(CD 3 ) 2 .

[0055] In some embodiments, Z is selected from C(CH 3) 2 or C(CD 3 ) 2 .

[0056] In some embodiments, Z is selected from O.

[0057] In the present invention, R 1 To R 3 are the same as or different from each other and are independently selected from hydrogen, deuterium or a group described by formula (b):

[0058]

[0059] Among them, R 4 ,R 5 As a bonding site, it bonds to formula (a); formula (a) satisfies the condition: R 1 ,R 2 ,R 3 There is only one group selected from the group described in formula (b).

[0060] In the present invention, Ar 1 ,Ar 2 Each is independently selected from a substituted or unsubstituted aryl group having 6 to 24 carbon atoms, and a substituted or unsubstituted heteroaryl group having 3 to 24 carbon atoms. The substituent in the "substituted or unsubstituted" includes, but is not limited to, deuterium, a halogen group, a cyano group, an alkyl group having 1 to 10 carbon atoms, a deuterated alkyl group having 1 to 10 carbon atoms, a cycloalkyl group having 3 to 10 carbon atoms, an alkoxy group having 1 to 10 carbon atoms, an aryl group having 6 to 20 carbon atoms, an aryl group having 6 to 20 carbon atoms substituted by an alkyl group, or a heteroaryl group having 3 to 20 carbon atoms. Optionally, the substituent in the "substituted or unsubstituted" is selected from deuterium, an alkyl or deuterated alkyl group having 1 to 6 carbon atoms, a cycloalkyl group having 3 to 10 carbon atoms, a phenyl group, a naphthyl group, a phenanthrenyl group, a methylphenyl group, a tert-butylphenyl group, a 9,9-dimethylfluorenyl group, a 9,9-diphenylfluorenyl group, a dibenzofuranyl group, a dibenzothienyl group, a benzonaphthothienyl group, and a benzonaphthofuranyl group. Among them, the alkyl or deuterated alkyl group having 1 to 6 carbon atoms may be, for example, a methyl group, an ethyl group, a n-propyl group, an isopropyl group, a n-butyl group, an isobutyl group, a tert-butyl group, and the like. The cycloalkyl group having 3 to 10 carbon atoms may be, for example, a cyclopropyl group, a cyclobutyl group, a cyclopentyl group, a cyclohexyl group, an adamantyl group, and the like.

[0061] In some embodiments, Ar 1 ,Ar 2Each is independently selected from a substituted or unsubstituted aryl group having 6 to 20 carbon atoms, and a substituted or unsubstituted heteroaryl group having 3 to 20 carbon atoms. The substituent in the "substituted or unsubstituted" includes, but is not limited to, deuterium, a halogen group, a cyano group, an alkyl group having 1 to 10 carbon atoms, a deuterated alkyl group having 1 to 10 carbon atoms, a cycloalkyl group having 3 to 10 carbon atoms, an alkoxy group having 1 to 10 carbon atoms, an aryl group having 6 to 20 carbon atoms, an aryl group having 6 to 20 carbon atoms substituted by an alkyl group, or a heteroaryl group having 3 to 20 carbon atoms. Optionally, the substituent in the "substituted or unsubstituted" is selected from deuterium, an alkyl or deuterated alkyl group having 1 to 6 carbon atoms, a cycloalkyl group having 3 to 10 carbon atoms, a phenyl group, a naphthyl group, a phenanthrenyl group, a methylphenyl group, a tert-butylphenyl group, a 9,9-dimethylfluorenyl group, a 9,9-diphenylfluorenyl group, a dibenzofuranyl group, a dibenzothienyl group, a benzonaphthothienyl group, and a benzonaphthofuranyl group. Among them, the alkyl or deuterated alkyl group having 1 to 6 carbon atoms may be, for example, a methyl group, an ethyl group, a n-propyl group, an isopropyl group, a n-butyl group, an isobutyl group, a tert-butyl group, and the like. The cycloalkyl group having 3 to 10 carbon atoms may be, for example, a cyclopropyl group, a cyclobutyl group, a cyclopentyl group, a cyclohexyl group, an adamantyl group, and the like.

[0062] In some embodiments, Ar 1 ,Ar 2 Each is independently selected from a substituted or unsubstituted aryl group having 6 to 18 carbon atoms, or a substituted or unsubstituted heteroaryl group having 3 to 18 carbon atoms. The substituents in the "substituted or unsubstituted" include, but are not limited to, deuterium, a halogen group, a cyano group, an alkyl group having 1 to 10 carbon atoms, a deuterated alkyl group having 1 to 10 carbon atoms, a cycloalkyl group having 3 to 10 carbon atoms, an alkoxy group having 1 to 10 carbon atoms, an aryl group having 6 to 20 carbon atoms, an aryl group having 6 to 20 carbon atoms substituted with an alkyl group, or a heteroaryl group having 3 to 20 carbon atoms. Optionally, the substituent in the "substituted or unsubstituted" is selected from deuterium, an alkyl or deuterated alkyl group having 1 to 6 carbon atoms, a cycloalkyl group having 3 to 10 carbon atoms, a phenyl group, a naphthyl group, a phenanthrenyl group, a methylphenyl group, a tert-butylphenyl group, a 9,9-dimethylfluorenyl group, a 9,9-diphenylfluorenyl group, a dibenzofuranyl group, a dibenzothienyl group, a benzonaphthothienyl group, and a benzonaphthofuranyl group. Among them, the alkyl or deuterated alkyl group having 1 to 6 carbon atoms may be, for example, a methyl group, an ethyl group, a n-propyl group, an isopropyl group, a n-butyl group, an isobutyl group, a tert-butyl group, and the like. The cycloalkyl group having 3 to 10 carbon atoms may be, for example, a cyclopropyl group, a cyclobutyl group, a cyclopentyl group, a cyclohexyl group, an adamantyl group, and the like.

[0063] In some embodiments, Ar 1 ,Ar 2Each is independently selected from a substituted or unsubstituted aryl group having 6 to 15 carbon atoms, and a substituted or unsubstituted heteroaryl group having 3 to 15 carbon atoms. The substituent in the "substituted or unsubstituted" includes, but is not limited to, deuterium, a halogen group, a cyano group, an alkyl group having 1 to 10 carbon atoms, a deuterated alkyl group having 1 to 10 carbon atoms, a cycloalkyl group having 3 to 10 carbon atoms, an alkoxy group having 1 to 10 carbon atoms, an aryl group having 6 to 20 carbon atoms, an aryl group having 6 to 20 carbon atoms substituted by an alkyl group, or a heteroaryl group having 3 to 20 carbon atoms. Optionally, the substituent in the "substituted or unsubstituted" is selected from deuterium, an alkyl or deuterated alkyl group having 1 to 6 carbon atoms, a cycloalkyl group having 3 to 10 carbon atoms, a phenyl group, a naphthyl group, a phenanthrenyl group, a methylphenyl group, a tert-butylphenyl group, a 9,9-dimethylfluorenyl group, a 9,9-diphenylfluorenyl group, a dibenzofuranyl group, a dibenzothienyl group, a benzonaphthothienyl group, and a benzonaphthofuranyl group. Among them, the alkyl or deuterated alkyl group having 1 to 6 carbon atoms may be, for example, a methyl group, an ethyl group, a n-propyl group, an isopropyl group, a n-butyl group, an isobutyl group, a tert-butyl group, and the like. The cycloalkyl group having 3 to 10 carbon atoms may be, for example, a cyclopropyl group, a cyclobutyl group, a cyclopentyl group, a cyclohexyl group, an adamantyl group, and the like.

[0064] In some embodiments, Ar 1 ,Ar 2 Each is independently selected from a substituted or unsubstituted aryl group having 6 to 12 carbon atoms, and a substituted or unsubstituted heteroaryl group having 3 to 12 carbon atoms. The substituent in the "substituted or unsubstituted" includes, but is not limited to, deuterium, a halogen group, a cyano group, an alkyl group having 1 to 10 carbon atoms, a deuterated alkyl group having 1 to 10 carbon atoms, a cycloalkyl group having 3 to 10 carbon atoms, an alkoxy group having 1 to 10 carbon atoms, an aryl group having 6 to 20 carbon atoms, an aryl group having 6 to 20 carbon atoms substituted by an alkyl group, or a heteroaryl group having 3 to 20 carbon atoms. Optionally, the substituent in the "substituted or unsubstituted" is selected from deuterium, an alkyl or deuterated alkyl group having 1 to 6 carbon atoms, a cycloalkyl group having 3 to 10 carbon atoms, a phenyl group, a naphthyl group, a phenanthrenyl group, a methylphenyl group, a tert-butylphenyl group, a 9,9-dimethylfluorenyl group, a 9,9-diphenylfluorenyl group, a dibenzofuranyl group, a dibenzothienyl group, a benzonaphthothienyl group, and a benzonaphthofuranyl group. Among them, the alkyl or deuterated alkyl group having 1 to 6 carbon atoms may be, for example, a methyl group, an ethyl group, a n-propyl group, an isopropyl group, a n-butyl group, an isobutyl group, a tert-butyl group, and the like. The cycloalkyl group having 3 to 10 carbon atoms may be, for example, a cyclopropyl group, a cyclobutyl group, a cyclopentyl group, a cyclohexyl group, an adamantyl group, and the like.

[0065] In some embodiments, Ar 1 ,Ar 2Selected from the following substituted or unsubstituted groups: phenyl, biphenyl, naphthyl, phenanthrenyl, fluorenyl, 9,9'-dimethylfluorenyl, 9,9'-diphenylfluorenyl, spirofluorenyl, spirofluorenyl, carbazolyl, dibenzothiophenyl, dibenzofuranyl, benzofluorenyl, benzospirofluorenyl, benzonaphthothiophenyl, benzonaphthofuranyl. The substituents in the "substituted or unsubstituted" include, but are not limited to, deuterium, halogen groups, cyano groups, alkyl groups having 1 to 10 carbon atoms, deuterated alkyl groups having 1 to 10 carbon atoms, cycloalkyl groups having 3 to 10 carbon atoms, alkoxy groups having 1 to 10 carbon atoms, aryl groups having 6 to 20 carbon atoms, aryl groups having 6 to 20 carbon atoms substituted by alkyl groups, or heteroaryl groups having 3 to 20 carbon atoms. Optionally, the substituent in the "substituted or unsubstituted" is selected from deuterium, an alkyl or deuterated alkyl group having 1 to 6 carbon atoms, a cycloalkyl group having 3 to 10 carbon atoms, a phenyl group, a naphthyl group, a phenanthrenyl group, a methylphenyl group, a tert-butylphenyl group, a 9,9-dimethylfluorenyl group, a 9,9-diphenylfluorenyl group, a dibenzofuranyl group, a dibenzothienyl group, a benzonaphthothienyl group, and a benzonaphthofuranyl group. Among them, the alkyl or deuterated alkyl group having 1 to 6 carbon atoms may be, for example, a methyl group, an ethyl group, a n-propyl group, an isopropyl group, a n-butyl group, an isobutyl group, a tert-butyl group, and the like. The cycloalkyl group having 3 to 10 carbon atoms may be, for example, a cyclopropyl group, a cyclobutyl group, a cyclopentyl group, a cyclohexyl group, an adamantyl group, and the like.

[0066] In the present invention, optionally, the hydrogen atom at any position in formula (a) and / or formula (b) may be substituted by deuterium.

[0067] In the present invention, when Z is selected from C(CH 3 ) 2 or C(CD 3 ) 2 When the triarylamine compound is selected from any one of the following structures:

[0068]

[0069] In the above chemical formulas, Ar 1 ,Ar 2 The meaning is the same as described above.

[0070] Optionally, in the above chemical formulas, any hydrogen atom can be replaced by deuterium. For example, the following structure can be used:

[0071]

[0072] In some preferred embodiments of the present invention, the compound represented by formula (a) is selected from any one of the following chemical structures:

[0073]

[0074]

[0075] In the present invention, when Z is selected from O, the triarylamine compound is selected from any one of the following structures:

[0076]

[0077] In the above chemical formulas, Ar 1 ,Ar 2 The meaning is the same as described above.

[0078] Optionally, in the above chemical formulas, any hydrogen atom can be replaced by deuterium.

[0079] In some preferred embodiments of the present invention, the compound represented by formula (a) is selected from any one of the following chemical structures:

[0080]

[0081]

[0082] Hereinafter, a functional layer to which the above triarylamine compound is applied, and an organic electroluminescent device, a display or a lighting device including the functional layer will be described.

[0083] The present application also provides an organic electroluminescent device, comprising a first electrode, a second electrode and the aforementioned organic layer. As an example, the first electrode is an anode, the second electrode is a cathode, and the cathode can be one or more layers. The organic layer is located between the first electrode and the second electrode. The organic layer can be a single-layer structure or a multilayer tandem structure in which two or more organic layers are laminated. The organic layer includes at least one of a hole injection layer, a hole transport layer, an electron blocking layer, a light-emitting layer, a hole blocking layer and an electron transport layer. In some preferred embodiments, the triarylamine compound of the present application is used as an electron blocking layer material, a hole transport layer material or a light-emitting layer main material.

[0084] In some specific embodiments, the structure of the organic electroluminescent device can be selected from one of the following:

[0085] (1) An organic electroluminescent device comprises an anode, a hole injection layer, a first hole transport layer, a light-emitting layer, a first electron transport layer, and a cathode stacked in sequence, that is, anode / hole injection layer / first hole transport layer / light-emitting layer / first electron transport layer / cathode. The device structure will be expressed in this simplified manner below.

[0086] (2) anode / hole injection layer / second hole transport layer / first hole transport layer / light-emitting layer / first electron transport layer / cathode.

[0087] (3) anode / hole injection layer / second hole transport layer / first hole transport layer / light-emitting layer / first electron transport layer / second electron transport layer / cathode.

[0088] (4) anode / hole injection layer / second hole transport layer / first hole transport layer / light-emitting layer / first electron transport layer / second electron transport layer / electron injection layer / cathode.

[0089] (5) Anode / hole injection layer / second hole transport layer / first hole transport layer / light-emitting layer / first electron transport layer / second electron transport layer / multilayer cathode.

[0090] (6) anode / hole injection layer / first hole transport layer / first light-emitting layer / carrier generation layer / first hole transport layer / second light-emitting layer / first electron transport layer / cathode.

[0091] (7) anode / hole injection layer / first hole transport layer / first light-emitting layer / carrier generation layer / first hole transport layer / second light-emitting layer / first electron transport layer / second electron transport layer / cathode.

[0092] (8) anode / hole injection layer / second hole transport layer / first hole transport layer / first light-emitting layer / carrier generation layer / first hole transport layer / second light-emitting layer / first electron transport layer / cathode.

[0093] (9) anode / hole injection layer / second hole transport layer / first hole transport layer / first light-emitting layer / carrier generation layer / first hole transport layer / second light-emitting layer / first electron transport layer / second electron transport layer / cathode.

[0094] (10) Anode / hole injection layer / hole transport layer / electron blocking layer / light-emitting layer / electron transport layer / electron injection layer / cathode.

[0095] (11) anode / hole injection layer / first hole transport layer / second hole transport layer / light-emitting layer / hole blocking layer / electron transport layer / cathode.

[0096] (12) Anode / hole injection layer / hole transport layer / electron blocking layer / light-emitting layer / electron transport layer / cathode.

[0097] (13) Anode / hole injection layer / hole transport layer / electron blocking layer / light-emitting layer / hole blocking layer / electron transport layer / cathode.

[0098] The light emission direction of the organic electroluminescent device can be emitted from the anode side or the cathode side. In some specific embodiments, if the light emission direction is from the cathode side, it is necessary to add another covering layer on the cathode side. The specific structure is as follows:

[0099] 1) Anode / hole injection layer / first hole transport layer / light-emitting layer / first electron transport layer / cathode / covering layer.

[0100] 2) Anode / hole injection layer / second hole transport layer / first hole transport layer / light-emitting layer / first electron transport layer / cathode / covering layer.

[0101] 3) anode / hole injection layer / second hole transport layer / first hole transport layer / light-emitting layer / first electron transport layer / second electron transport layer / cathode / covering layer.

[0102] 4) anode / hole injection layer / second hole transport layer / first hole transport layer / light-emitting layer / first electron transport layer / second electron transport layer / electron injection layer / cathode / covering layer.

[0103] 5) anode / hole injection layer / second hole transport layer / first hole transport layer / light-emitting layer / first electron transport layer / second electron transport layer / multilayer cathode / covering layer.

[0104] 6) anode / hole injection layer / first hole transport layer / first light-emitting layer / carrier generation layer / first hole transport layer / second light-emitting layer / first electron transport layer / cathode / covering layer.

[0105] 7) anode / hole injection layer / first hole transport layer / first light-emitting layer / carrier generation layer / first hole transport layer / second light-emitting layer / first electron transport layer / second electron transport layer / cathode / covering layer.

[0106] 8) anode / hole injection layer / second hole transport layer / first hole transport layer / first light-emitting layer / carrier generation layer / first hole transport layer / second light-emitting layer / first electron transport layer / cathode / covering layer.

[0107] 9) anode / hole injection layer / second hole transport layer / first hole transport layer / first light-emitting layer / carrier generation layer / first hole transport layer / second light-emitting layer / first electron transport layer / second electron transport layer / cathode / covering layer.

[0108] 10) Anode / hole injection layer / hole transport layer / electron blocking layer / light-emitting layer / electron transport layer / electron injection layer / cathode / covering layer.

[0109] 11) Anode / hole injection layer / first hole transport layer / second hole transport layer / light-emitting layer / hole blocking layer / electron transport layer / cathode / covering layer.

[0110] 12) Anode / hole injection layer / hole transport layer / electron blocking layer / light-emitting layer / electron transport layer / cathode / covering layer.

[0111] 13) Anode / hole injection layer / hole transport layer / electron blocking layer / light-emitting layer / hole blocking layer / electron transport layer / cathode / covering layer (device structure of the blue light embodiment of the present application).

[0112] Some specific functional layers in the organic electroluminescent device will be described below.

[0113] Substrate:

[0114] The substrate is generally located below the anode, and the substrate may be made of plastic or glass, and may be rigid or bendable. The substrate is provided with a driving unit, which may drive the corresponding pixel to emit light.

[0115] anode:

[0116] Organic EL (Organic Electro-Luminescence) components usually have requirements for the anode to have good conductivity, a flat surface, and not prone to cracks. At the same time, there are certain requirements for the work function, mainly to be able to match the hole injection layer and exert the hole injection effect.

[0117] When the top emission mode (light emitting from the cathode side) is adopted, the anode adopts a metal compound with a work function of 4.2eV or more, such as indium tin oxide alloy, tin oxide, indium zinc oxide, gold, silver, platinum, copper, carbon nanotubes, carbon nanowires, graphene, etc. The thickness is 10nm to 200nm, preferably 10nm to 50nm. A reflective electrode is set under the anode (close to the substrate end). The reflective electrode is generally made of metal or metal alloy, such as silver metal, copper metal, aluminum metal, gold metal or alloys of these metals and other metals. The reflectivity of the reflective electrode is relatively high, and the reflectivity is required to be above 90%. The thickness is usually used at a thickness of 100nm to 500nm, preferably in the range of 80nm to 150nm.

[0118] When the bottom emission mode (light emitting from the negative substrate side) is adopted, the anode adopts a metal compound with a work function of 4.2eV or more, for example, indium tin oxide alloy, tin oxide, indium zinc oxide, gold, silver, platinum, copper, carbon nanotubes, carbon nanowires, graphene, etc. The thickness is 10nm to 1μm, preferably 50nm to 200nm.

[0119] The anode can be produced by forming an electrode material into a thin film by a method such as vapor deposition, sputtering, or coating.

[0120] Hole injection layer:

[0121] The thickness of the hole injection layer is generally 3nm to 20nm. The hole injection layer is a mixture of P-type materials and hole transport materials. The purpose of using P-type materials is to receive holes from the anode and transfer them to the hole transport material. The weight proportion of P-type materials in the hole injection layer is generally 0.5% to 10%. When the weight proportion is 0.5% to 3%, the absolute value of the difference between the lowest unoccupied molecular orbital (LUMO) energy level of the P-type material and the highest occupied molecular orbital (HOMO) energy level of the HTL material shall not be greater than 0.3eV. When the weight proportion is 3% to 5%, the absolute value of the difference between the lowest unoccupied molecular orbital (LUMO) energy level of the P-type material and the highest occupied molecular orbital (HOMO) energy level of the HTL material shall not be greater than 0.5eV. When the weight proportion is 5% to 10%, the absolute value of the difference between the lowest unoccupied molecular orbital (LUMO) energy level of the P-type material and the highest occupied molecular orbital (HOMO) energy level of the HTL material shall not be greater than 1eV.

[0122] The P-type material can be made of metal oxides, such as molybdenum oxide, vanadium oxide, tungsten oxide, etc.; it can also be made of organic matter, such as 4,4',4"-((1E,1'E,1"E)-cyclopropane-1,2,3-trimethylene tris(cyanoformylidene))tris(2,3,5,6-tetrafluorobenzyl) (PD1, CAS No.: 1224447-88-4), tetracyanoquinodimethane (TCNQ), 2,3,5,6-tetrafluoro-tetracyano-1,4-benzoquinodimethane (F4-TCNQ), 2,3,6,7,10,11-hexacyano-1,4,5,8,9,12-hexaazatriphenylene (HAT-CN), and is not limited thereto. The hole transport material matched with the P-type material can be selected from the material of the second hole transport layer, and can be the same as the material of the second hole transport layer or different.

[0123] Second hole transport layer:

[0124] The thickness of the second hole transport layer is generally 40nm to 150nm, and aromatic amine compounds are often used, which can be aromatic monoamines or aromatic polyamines. The hole transport material is required to have high hole mobility, be able to reduce the driving voltage, and have a glass transition temperature exceeding 100°C to avoid crystallization at high temperatures.

[0125] First hole transport layer:

[0126] The thickness of the first hole transport layer is generally 3nm to 220nm. When there is no second hole transport layer, the thickness of the first hole transport layer is generally 40nm to 150nm; when there is a second hole transport layer, the thickness of the first hole transport layer is generally 3nm to 120nm. In general, red light, green light, blue light, yellow light, etc. need to be adjusted in thickness according to the "microcavity effect", and the thickness selection is also different. Taking the top-emitting light-emitting device as an example, the formula for the microcavity is as follows:

[0127]

[0128] where n i ,d i Respectively indicate the refractive index and thickness of the i-th layer, m is an integer, which is the modulus of the microcavity, and is more commonly 1 or 2; θ 1 ,θ 2 They represent the phase shift of light at the anode interface and the cathode interface respectively.

[0129] Red light, green light, blue light or other colors of light have different wavelengths, so each color has its optimal thickness. Taking the modulus of 2 as an example, for red light, when there is no second hole transport layer, the thickness of the first hole transport layer is generally 160nm~220nm; when there is a second hole transport layer, the thickness of the first hole transport layer is generally 8nm~120nm. For green light, when there is no second hole transport layer, the thickness of the first hole transport layer is generally 100nm~180nm; when there is a second hole transport layer, the thickness of the first hole transport layer is generally 30nm~70nm. For blue light, when there is no second hole transport layer, the thickness of the first hole transport layer is generally 80nm~130nm; when there is a second hole transport layer, the thickness of the first hole transport layer is generally 3nm~30nm. When other colors are selected, there will be different optimal "microcavity adjustment thicknesses".

[0130] Electron blocking layer:

[0131] The electron blocking layer can have both hole transport and electron blocking functions. At the same time, the higher triplet excitation energy level of the electron blocking layer can lock the excitons generated in the light-emitting layer in the light-emitting layer, thereby improving the luminous efficiency of the device.

[0132] Luminous layer:

[0133] The material of the light-emitting layer generally includes a host material and a guest dopant material. The content of the host material is greater than that of the guest dopant material. Optionally, the mass percentage of the guest dopant material in the light-emitting layer is 1% to 20%.

[0134] The guest doping material as the luminescent material may include phosphorescent or fluorescent materials or thermally activated delayed fluorescent materials, and red light, green light, and blue light may be selected from the above three guest doping materials. For example, the guest doping material of the luminescent layer corresponding to the luminescent unit with a red luminescent color and the luminescent layer corresponding to the luminescent unit with a green luminescent color is a phosphorescent material, and the guest doping material of the luminescent layer corresponding to the luminescent unit with a blue luminescent color is a fluorescent material.

[0135] Or for example, the guest doping material of the light-emitting layer corresponding to the light-emitting unit with red light-emitting color and the light-emitting layer corresponding to the light-emitting unit with green light-emitting color is a phosphorescent material, and the guest doping material of the light-emitting layer corresponding to the light-emitting unit with blue light-emitting color is a phosphorescent material.

[0136] Or for example, the guest doping material of the light-emitting layer corresponding to the light-emitting unit with red light-emitting color and the light-emitting layer corresponding to the light-emitting unit with green light-emitting color is a thermally activated delayed fluorescent material, and the guest doping material of the light-emitting layer corresponding to the light-emitting unit with blue light-emitting color is a fluorescent material.

[0137] Or for example, the guest doping material of the light-emitting layer corresponding to the light-emitting unit with red light-emitting color and the light-emitting layer corresponding to the light-emitting unit with green light-emitting color is a thermally activated delayed fluorescent material, and the guest doping material of the light-emitting layer corresponding to the light-emitting unit with blue light-emitting color is a phosphorescent material.

[0138] In order to reduce the power consumption of the organic light-emitting display panel in the organic electroluminescent device, the guest doping material can be selected to have excellent light-emitting performance. Taking the top-emitting device as an example, optionally, the light-emitting unit with a red light-emitting color has a light-emitting brightness of 1000 cd / m 2 The current efficiency is greater than 30cd / A, and the green luminous unit has a luminous brightness of 6000cd / m 2 The current efficiency is greater than 100cd / A, and the light-emitting unit with fluorescent blue light color has a light brightness of 1000cd / m 2 The current efficiency is greater than 5cd / A as the standard, and the appropriate guest doping material is selected. The light-emitting unit with a phosphorescent blue light color has a light-emitting brightness of 1000cd / m 2 The current efficiency is greater than 10cd / A. When the current efficiency is higher, the power consumption can be reduced.

[0139] As the light-emitting host material, one light-emitting host material or two light-emitting host materials may be selected.

[0140] Hole blocking layer:

[0141] In order to enhance the balance of hole and electron concentrations, a hole blocking layer is inserted to balance the carrier concentration and prevent exciton quenching. Generally, the hole blocking layer is located between the light-emitting layer and the electron transport layer. The hole blocking layer material must meet the conditions of strong stability, good film-forming properties, and a sufficiently high highest molecular occupied orbital.

[0142] First electron transport layer:

[0143] The thickness of the first electron transport layer can generally be 3nm to 40nm, 3nm to 10nm, 10nm to 20nm, 20nm to 30nm, 30nm to 40nm or 20nm to 40nm, etc. When there is no second electron transport layer, the thickness of the first electron transport layer is generally 20nm to 50nm, and when there is a second electron transport layer, the thickness of the first electron transport layer is generally 40nm to 20nm. The first electron transport layer is in direct contact with the light-emitting layer, so similar to the first hole transport layer, electronic changes will also occur during the electron transport process, resulting in increased molecular vibration and molecular deformation. It will also be because the excitons of the light-emitting layer interact with the polarons of the electron transport material. This action is likely to produce active free radicals and destroy the electron transport material. The electron transport material can be a single compound or mixed with other metals or metal compounds. It can include a mixture of organic electron transport materials and metal compounds, or a mixture of organic electron transport materials and metals.

[0144] When the organic electron transport material is mixed with a metal compound material, for example, it is mixed with an alkali metal compound, an alkaline earth metal compound, a rare earth metal compound, and more specifically, it is mixed with a metal lithium compound, a metal calcium compound, a metal Mg compound, a metal samarium compound, a metal ytterbium compound, and more specifically, it is mixed with 8-hydroxyquinoline lithium, lithium fluoride, magnesium fluoride, ytterbium fluoride, calcium fluoride, etc. When mixed with a metal compound, the mass proportion of the organic electron transport material can be 20% to 80%, 20% to 40%, 40% to 60%, or 60% to 80%, etc.

[0145] When the organic electron transport material is mixed with a metal, for example, mixed with an alkali metal, an alkaline earth metal, or a rare earth metal, more specifically, mixed with lithium metal, magnesium metal, calcium metal, ytterbium metal, samarium metal, etc., when mixed with a metal, the mass proportion of the organic electron transport material can be 80% to 99%, 80% to 89%, 89% to 99%, 80% to 85%, 85% to 90%, 90% to 95%, or 95% to 99%, etc.

[0146] Second electron transport layer:

[0147] The thickness of the second electron transport layer is generally 10 nm to 40 nm, and the material of the second electron transport layer may include a mixture of an organic electron transport material and a metal compound, or a mixture of an organic electron transport material and a metal.

[0148] When the organic electron transport material is mixed with a metal compound material, for example, it is mixed with an alkali metal compound, an alkaline earth metal compound, a rare earth metal compound, and more specifically, it is mixed with a metal lithium compound, a metal calcium compound, a metal Mg compound, a metal samarium compound, a metal ytterbium compound, and more specifically, it is mixed with 8-hydroxyquinoline lithium, lithium fluoride, magnesium fluoride, ytterbium fluoride, calcium fluoride, etc. When mixed with a metal compound, the mass proportion of the organic electron transport material can be 20% to 80%, 20% to 40%, 40% to 60%, or 60% to 80%, etc.

[0149] When the organic electron transport material is mixed with a metal, for example, mixed with an alkali metal, an alkaline earth metal, or a rare earth metal, more specifically, mixed with lithium metal, magnesium metal, calcium metal, ytterbium metal, samarium metal, etc., when mixed with a metal, the mass proportion of the organic electron transport material can be 80% to 99%, 80% to 89%, 89% to 99%, 80% to 85%, 85% to 90%, 90% to 95%, or 95% to 99%, etc.

[0150] Charge generation layer:

[0151] When a single-layer light-emitting layer device is used, holes and electrons are injected from the anode and cathode respectively, and a charge generation layer is not required. When a double-layer or multi-layer light-emitting layer is used, a charge generation layer is required between the light-emitting layers to achieve the effect of charge generation, injection and transmission. The charge generation layer is located between the two light-emitting layers, and is generally composed of two layers of P / N type materials, wherein the P-type material is selected from the hole injection material mentioned above, and the N-type material is mixed with an organic electron transport material doped with a metal. The organic electron transport layer material is selected from the second electron transport layer mentioned above, and the metal is selected from alkali metals, alkaline earth metals, and rare earth metals, and more specifically, lithium metal, magnesium metal, calcium metal, ytterbium metal, samarium metal, etc. When the organic electron transport material is mixed with the metal, the mass proportion of the organic electron transport material can be 80% to 99%, 80% to 89%, 89% to 99%, 80% to 85%, 85% to 90%, 90% to 95%, or 95% to 99%, etc.

[0152] cathode:

[0153] The cathode requires a material with good electrical conductivity and good surface flatness. In order to improve the electron injection capability, a material with a small work function is usually selected. The cathode material can be a single-layer cathode, or a double-layer or multi-layer cathode, generally a metal or a metal alloy. For a single-layer cathode, silver, copper, aluminum, gold, or alloys of these metals with other metals, such as alloys with rare earth metals, alkali metals, and alkaline earth metals, can be used, which can be listed as magnesium-indium alloy, magnesium-aluminum alloy, aluminum-potassium alloy, aluminum-scandium-potassium alloy, magnesium-silver alloy, silver-ytterbium alloy, silver-samarium alloy, etc. If the cathode uses a double-layer metal, the cathode near the light-emitting layer can use alkali metals, alkaline earth metals, rare earth metals, etc., such as lithium, calcium, magnesium, ytterbium, etc., to increase the electron injection ability, and the cathode layer far from the light-emitting side is mainly used to improve the conductivity. Generally, silver, copper, aluminum, gold or alloys of these metals with other metals, such as alloys with rare earth metals, alkali metals, and alkaline earth metals can be used, which can be listed as magnesium-indium alloy, magnesium-aluminum alloy, aluminum-potassium alloy, aluminum-scandium-potassium alloy, magnesium-silver alloy, silver-ytterbium alloy, silver-samarium alloy, etc. The cathode can also be formed into a thin film by evaporation, sputtering, etc.

[0154] When light comes out from the anode side, the cathode is required to be light-proof, and a cathode with a thickness greater than 100nm can be evaporated. When light comes out from the cathode side, the cathode is required to be transparent, and the transmittance should be greater than 40% at this time, and the thickness should be 10nm to 20nm.

[0155] Overlay:

[0156] The refractive index n and absorption coefficient of the single-layer cover layer need to meet the following conditions:

[0157] The refractive index between the wavelengths of 450 and 650 nm is n(450-650nm)>1.8, and the extinction coefficient between the wavelengths of 450 and 650nm is below 0.1; the extinction coefficient at 380nm is greater than 0.2; the difference between the refractive index of 450nm and the refractive index of 530nm is n(450nm)-n(530nm)<0.5, more preferably n(450nm)-n(530nm)<0.3; the difference between the refractive index of 510nm and the refractive index of 620nm is n(510nm)-n(620nm)<0.4, more preferably the difference between the refractive index of 510nm and the refractive index of 620nm is n(510nm)-n(620nm)<0.2.

[0158] The material that can meet the requirements of the cover layer for the refractive index n can further achieve high luminous efficiency of the device, while the light output efficiency and viewing angle of red light, green light and blue light are more balanced.

[0159] In some specific embodiments, the thickness of the covering layer is 50nm to 90nm, for example, 50nm, 55nm, 57nm, 59nm, 62nm, 64nm, 67nm, 68nm, 70nm, 75nm, 77nm, 79nm, 80nm, 82nm, 85nm, 88nm, 90nm, etc.

[0160] The covering layer is formed after the semi-transparent cathode of the OLED display panel is away from the substrate, so that the light transmittance of the stacked layer formed by the covering layer and the semi-transparent cathode between 450nm and 650nm is ≥65%, for example, 68%, 69%, 73%, 77%, 79%, 83%, 88%, 93%, etc.

[0161] When two layers of cover are used, the refractive index n and the absorption coefficient need to meet the following conditions:

[0162] The covering layer close to the cathode side (the first covering layer) has a refractive index n450~650nm<1.8 between 450 and 650nm, and an extinction coefficient between 450 and 650nm below 0.1; the maximum coefficient at any wavelength between 250nm and 350nm is greater than 0.3, and optimally greater than 0.6.

[0163] The covering layer (second covering layer) away from the cathode side has a refractive index n450~650nm>1.8 between 450 and 650nm, and an extinction coefficient between 450 and 650nm is below 0.1; the extinction coefficient at 380nm is greater than 0.1, and more preferably greater than 0.2.

[0164] The difference between the refractive index at 450 nm and the refractive index at 530 nm is n(450 nm)-n(530 nm)<0.5, and more preferably, the difference between the refractive index at 450 nm and the refractive index at 530 nm is n(450 nm)-n(530 nm)<0.3;

[0165] The difference between the refractive index at 510 nm and the refractive index at 620 nm is n(510 nm)-n(620 nm)<0.4, and more preferably, the difference between the refractive index at 450 nm and the refractive index at 530 nm is n(450 nm)-n(530 nm)<0.2.

[0166] The total thickness of the double-layer covering layer is 50nm to 90nm, for example: 50nm, 55nm, 57nm, 59nm, 62nm, 64nm, 67nm, 68nm, 70nm, 75nm, 77nm, 79nm, 80nm, 82nm, 85nm, 88nm, 90nm, etc.

[0167] The thickness of the covering layer (first covering layer) close to the cathode side is 5nm to 40nm, for example: 5nm, 7nm, 10nm, 12nm, 15nm, 18nm, 20nm, 22nm, 25nm, 27nm, 30nm, 32nm, 34nm, 36nm, 38nm, 40nm, etc.

[0168] The thickness of the covering layer (second covering layer) away from the cathode side is 35nm to 85nm, for example: 35nm, 40nm, 43nm, 45nm, 48nm, 50nm, 55nm, 57nm, 59nm, 62nm, 64nm, 67nm, 68nm, 70nm, 75nm, 77nm, 79nm, 80nm, 82nm, 85nm, etc.

[0169] On the other hand, the present application further provides a display device, comprising the above-mentioned organic electroluminescent device.

[0170] Synthesis Example:

[0171] The specific preparation method of the above-mentioned new compound of the present invention will be described in detail below by taking multiple synthesis examples as examples, but the preparation method of the present invention is not limited to these multiple synthesis examples. Those skilled in the art can make any modifications, equivalent substitutions, improvements, etc. on this basis without departing from the principles of the present invention, and expand the method to the scope of the technical solution claimed for protection by the claims of the present invention.

[0172] Synthesis and testing methods

[0173]

Raw materials and reagents

[0174] The initial raw materials and solvents of the present invention were purchased from Shanghai Titan Technology Co., Ltd., some commonly used OLED intermediates and other products were purchased from domestic OLED intermediate manufacturers; various palladium catalysts, ligands, etc. were purchased from Shaanxi Ruike New Materials Co., Ltd.

[0175]

Cross-coupling synthesis

[0176] The synthesis of the bistriarylamine compound represented by the above formula (a) can be carried out using known methods. For example, a cross-coupling reaction using transition metals such as nickel and palladium. Other synthesis methods are CC, CN coupling reactions using transition metals such as magnesium or zinc. The above reactions are limited to the characteristics of mild reaction conditions and superior selectivity of various functional groups, and preferably Suzuki and Buchwald reactions. The cycloalkane and heterocycloalkane derivatives of the present invention are illustrated by the following examples, but are not limited to the cycloalkane and heterocycloalkane derivatives and synthesis methods illustrated in these examples.

[0177] In an inert atmosphere, reaction A and the reactants are heated in an organic solvent in the presence of a cross-coupling catalyst (catalytic amount), and reflux heating and stirring are performed during the reaction. After the desired reaction time, the reaction system is cooled and water is added, and the precipitated solid is washed and vacuum dried to obtain a crude product. The obtained crude product is refined (including but not limited to silica gel column chromatography) to obtain a product.

[0178]

Test method

[0179] 1 H NMR data were measured using a (400 MHz) nuclear magnetic resonance instrument (manufactured by Bruker, Germany); HPLC data were measured using a Waters Corporation UPLC ultra-high performance liquid chromatograph. Mass spectra were measured using a Waters Corporation single quadrupole mass spectrometer.

[0180] Synthesis of compound 1:

[0181]

[0182] 1. Synthesis of intermediate compound 1-ii

[0183] Under nitrogen atmosphere, 5-bromo-2-chloro-9,9-dimethyl-9H-fluorene (Compound 1-I, 10.0 g, 32.5 mmol, 1 eq), biboric acid pinacol ester (9.0 g, 35.7 mmol, 1.1 eq), Pd(dppf)Cl 2 (230mg, 0.32mmol, 1%eq), potassium acetate (12.8g, 65.0mmol, 2eq) and degassed toluene (180mL), start stirring, mix the above reaction system thoroughly, and heat to 125°C under nitrogen atmosphere for 6 hours. There is basically no raw material remaining by thin layer chromatography analysis. The reaction system is cooled to room temperature, dichloromethane (50mL) is added, and the layers are separated after standing. The organic phase is collected, the aqueous phase is extracted with toluene (3x30mL), the organic phases are combined, dried over anhydrous magnesium sulfate, filtered, and the solvent is removed by rotary evaporation. The crude product is separated by rapid silica gel column chromatography to obtain compound 1-ii (9.8g, yield 85.0%).

[0184] 2. Synthesis of intermediate compound 1-iv

[0185] Under nitrogen atmosphere, 7-phenyldibenzofuran-1-yl trifluoromethanesulfonate (compound 1-iii, 8.0 g, 20.3 mmol, 1 eq), compound 1-ii (8.0 g, 22.4 mmol, 1.1 eq), sodium bicarbonate (3.4 g, 40.7 mmol, 2 eq), Pd(dppf)Cl were added successively into a dry three-necked flask. 2 (0.15g, 0.2mmol, 1%eq), toluene (50mL), anhydrous ethanol (25mL) and water (25mL). Stirring was started, the above reaction system was fully mixed, and the temperature was raised to reflux under a nitrogen atmosphere. After 6 hours of reaction, there was basically no raw material remaining by thin layer chromatography analysis, and heating was stopped. When the temperature of the reaction system dropped to room temperature, a mixed solution of 5mL concentrated hydrochloric acid (37% aqueous solution) and 100mL deionized water was added thereto, and the layers were allowed to stand, and the liquids were separated with a separatory funnel, the organic phase was retained, and the aqueous phase was extracted with toluene (3×20mL), combined with the above-retained organic phase, and the solvent was removed by reduced pressure distillation. The crude product was separated by silica gel column chromatography and recrystallized from a mixed solvent of toluene / ethanol to obtain compound 1-iv (7.3g, yield 76.3%).

[0186] 3. Synthesis of Compound 1

[0187] Under nitrogen atmosphere, compound 1-iv (7.3 g, 15.4 mmol, 1 eq), di(4-biphenyl)amine (4.9 g, 15.4 mmol, 1 eq), sodium tert-butoxide (2.2 g, 23.2 mmol, 1.5 eq), 2-dicyclohexylphosphine-2′,6′-dimethoxy-biphenyl (164.2 mg, 0.4 mmol, 4% eq), tris(dibenzylideneacetone)dipalladium (0.24 g, 0.15 mmol, 2% eq), (C 4 H 9 )PBF 4 (164.2mg, 0.4mmol, 4%eq) and degassed toluene (100mL). Stirring was started, the above reaction system was fully mixed, and the temperature was raised to 120°C under a nitrogen atmosphere. After 20 hours of reaction, there was basically no raw material remaining by thin layer chromatography analysis, and heating was stopped. When the temperature of the reaction system dropped to room temperature, a mixed solution of 5mL concentrated hydrochloric acid (37% aqueous solution) and 100mL deionized water was added thereto, and the layers were allowed to stand and separated with a separatory funnel, the organic phase was retained, and the aqueous phase was extracted with toluene (3×20mL), combined with the above-retained organic phase, and the solvent was removed by reduced pressure distillation. The crude product was separated by silica gel column chromatography (the mobile phase was a mixed solvent of n-hexane / toluene), and recrystallized from a mixed solvent of toluene / ethanol to obtain compound 1. The total yield of the three-step reaction was 34.5%. Mass spectrum (m / z) = 756.32 [M+H] + .

[0188] Referring to the preparation method of compound 1, the compounds listed in Table 1 were synthesized. For each compound x, the raw materials or intermediate compounds 1-ii, 1-iv and 1-v involved in the above preparation method are represented by x-ii, x-iv and xv, respectively. Among them, the main raw materials used, the synthesized intermediates, the yields and the mass spectrometry characterization data are shown in Table 1A and Table 1B.

[0189] Table 1A

[0190]

[0191]

[0192]

[0193] Table 1B

[0194]

[0195]

[0196]

[0197]

[0198] The NMR data of the representative compounds involved in the synthesis examples are shown in Table 2.

[0199] Table 2

[0200]

[0201]

[0202] Device Example:

[0203] The compounds used in the device are all purified by sublimation, and the purity is greater than 99.98%.

[0204] The compound involved in the present invention can be used as an electron blocking layer material for OLED devices with multiple colors such as green light and blue light. The specific device manufacturing method and test results are given below.

[0205] Green light device embodiment 1:

[0206] According to Figure 1The structure shown is used to make a green bottom-emitting organic electroluminescent device, and the preparation process is as follows: on a glass substrate 101, a transparent ITO film layer (thickness 150nm) is formed by a magnetron sputtering process to obtain a first electrode 102 as an anode. A mixed material of compound M1 and compound M2 is evaporated on the surface of the anode as a hole injection layer 103, with a mixing ratio of 3:97 (mass ratio) and a thickness of 10nm; then compound M2 (thickness 100nm) and compound 1 of the present invention (thickness 40nm) are sequentially evaporated on the surface of the hole injection layer to obtain a hole transport layer 104 and an electron blocking layer 105, respectively. Next, on the surface of the electron blocking layer 105, compound M3, compound M4 and compound M5 are co-evaporated at a mass ratio of 45:45:10 to form an organic light-emitting layer 106 (thickness 40nm). Subsequently, compound M6 is sequentially evaporated on the surface of the organic light-emitting layer to form a hole blocking layer 107 (thickness 10 nm), and compound M7 and LiQ with a mixing ratio of 4:6 (mass ratio) are formed into an electron transport layer 108 (thickness 30 nm). Finally, magnesium (Mg) and silver (Ag) are mixed and deposited on the surface of the electron transport layer 108 at an evaporation rate of 1:9 to form a second electrode 109 with a thickness of 10 nm as a cathode, completing the manufacture of the organic light-emitting device.

[0207] The chemical structures of compounds M1 to M7 and LiQ are shown in Table 3.

[0208] Table 3

[0209]

[0210]

[0211] Green light device embodiments 2 to 24

[0212] Green light device embodiments 2 to 24 were prepared in the same manner as green light device embodiment 1, except that when forming the electron blocking layer, compound 1 was replaced by the compounds in Table 4-2 and Table 4-3, respectively.

[0213] Comparative Examples 1 to 3

[0214] The organic electroluminescent device was prepared in the same manner as in Example 1 of the green light device, except that compound C1 to C4 (chemical structures shown below) were used to replace compound 1 when forming the light-emitting layer.

[0215]

[0216] The operating voltage and efficiency of the organic electroluminescent device prepared as above were calculated by a computer-controlled Keithley 2400 test system (test current was 20 mA / cm 2The device lifetime under dark conditions was obtained using a Foster lifetime measurement system equipped with a power supply and a photodiode as a detection unit (test conditions: ambient temperature 25°C, constant current 20 mA / cm 2 LT95 refers to the time required for the brightness to decrease from the initial brightness to 95%. The test results are shown in Table 4-1, Table 4-2 and Table 4-3.

[0217] Table 4-1

[0218]

[0219] Table 4-2 (Compounds in Group A corresponding to green light devices)

[0220]

[0221] Table 4-3 (Green light devices obtained from compounds in Group B)

[0222]

[0223]

[0224] Blue light device embodiment 1:

[0225] According to Figure 2 The structure shown is used to make a blue top-emitting organic electroluminescent device, and the preparation process is as follows: on a glass substrate 101, a transparent ITO film layer (thickness 150nm) is formed by a magnetron sputtering process to obtain a first electrode 102 as an anode. A mixed material of compound M1 and compound M2 is evaporated on the surface of the anode as a hole injection layer 103, with a mixing ratio of 3:97 (mass ratio) and a thickness of 10nm; then compound M2 (thickness 100nm) and compound 7 of the present invention (thickness 20nm) are sequentially evaporated on the surface of the hole injection layer to obtain a hole transport layer 104 and an electron blocking layer 105, respectively. Next, on the surface of the electron blocking layer 105, compound M4-B and compound M5-B are co-evaporated at a mass ratio of 95:5 to form an organic light-emitting layer 106 (thickness 30nm). Subsequently, compound M6 was sequentially evaporated on the surface of the organic light-emitting layer to form a hole blocking layer 107 (thickness 10 nm), and compound M7 and LiQ with a mixing ratio of 4:6 (mass ratio) formed an electron transport layer 108 (thickness 30 nm). Subsequently, magnesium (Mg) and silver (Ag) were mixed and deposited on the surface of the electron transport layer 108 at an evaporation rate of 1:9 to form a second electrode 109 with a thickness of 10 nm as a cathode. Finally, compound M8 with a thickness of 70 nm was evaporated as a covering layer to complete the manufacture of the organic light-emitting device.

[0226] During the device preparation process, the vacuum degree was maintained at 2×10 -7Torr to 5×10 -6 Torr; the evaporation rate of organic matter is between to The evaporation rate of aluminum is Thus, the manufacturing of the organic light-emitting device is completed. The chemical structures of compounds M1 to M7 and LiQ are as described above, and the chemical structures of compounds M4-B, M5-B, and M8 are shown in Table 5:

[0227] Table 5

[0228]

[0229] Blue light device embodiments 2 to 15

[0230] The blue light device embodiments 2 to 18 were prepared by the same method as the blue light device embodiment 1, except that when forming the electron blocking layer, the compounds in Table 6-2 and Table 6-3 were used to replace Compound 1.

[0231] Comparative Examples 4 to 6

[0232] The organic electroluminescent device was prepared in the same manner as in Example 1 of the blue light device, except that compound C4, C5 and C2 (chemical structures shown below) were used to replace compound 1 when forming the light-emitting layer.

[0233]

[0234] The operating voltage and efficiency of the organic electroluminescent device prepared as above were calculated by a computer-controlled Keithley 2400 test system (test current was 20 mA / cm 2 The device lifetime under dark conditions was obtained using a Foster lifetime measurement system equipped with a power supply and a photodiode as a detection unit (test conditions: ambient temperature 25°C, constant current 20 mA / cm 2 LT95 refers to the time required for the brightness to decrease from the initial brightness to 95%. The test results are shown in Table 6-1, Table 6-2, and Table 6-3.

[0235] Table 6-1

[0236]

[0237] Table 6-2 (Compounds in Group A corresponding to blue light devices)

[0238]

[0239] Table 6-3 (Compounds in Group B corresponding to blue light devices)

[0240]

[0241] The triarylamine compounds provided by the present invention are:

[0242] 1. The 2-position of the fluorenyl group or the 3-position of the dibenzofuranyl group is connected to the aromatic amine group, which has better conjugation than the bonding at other positions, ensuring that the molecule has good hole migration properties.

[0243] 2. More specifically, an aromatic group is introduced at the asymmetric position of the fluorenyl or dibenzofuranyl group. On the one hand, the aromatic group has a certain steric hindrance effect, which helps to form an amorphous film during the device preparation process; on the other hand, the molecule has a higher triplet energy level, so when it acts as an electron blocking layer, it is helpful to resist electrons and high-energy excitons, making it difficult for them to leak from the light-emitting layer, thereby ensuring the efficiency of the device.

[0244] 3. In particular, when the 2-position of the fluorenyl group is connected to an arylamine group and an aryl group is introduced at an asymmetric position, it has a more unexpected effect compared to the bonding at other positions, and even has an outstanding effect compared to the "3-position of the dibenzofuranyl group connected to an arylamine group". The reason is that the dimethylfluorenyl group containing an alkyl group has a certain electron-donating property, while dibenzofuran has a certain electron-withdrawing property. The fluorenyl group and the dibenzofuranyl group are bonded to each other to form a strong intramolecular interaction, which is particularly beneficial to the transport of carriers, so the device as a whole has a higher efficiency.

[0245] 4. The aromatic group described in the aforementioned point 2 is 3'-phenyl-dibenzofuran-1-yl or 3'-phenyl-dibenzofuran-4-yl. Among them, dibenzofuran-1-yl and dibenzofuran-4-yl are substituents with certain electron-withdrawing properties. As an electron blocking layer, electrons or high-energy excitons are more inclined to attack the electron-withdrawing fragments of the molecule, so that the electrons or high-energy excitons attack away from the CN bond, and the stability of the triarylamine structure is guaranteed; further, a phenyl group is further introduced at the 3'-position of the above-mentioned dibenzofuranyl, so that the conjugation of the dibenzofuranyl is further extended. When the electrons or high-energy excitons attack, the charge or energy they carry can be shared in a larger conjugated plane, so that the stability of the molecule is further improved, and the life of the device is improved.

[0246] 5. In combination with Table 4-1, Table 4-2 and Table 4-3, for green light devices, comparative compounds C1, C2, and the compounds provided by the present invention all contain asymmetric dibenzofuranyl-substituted fluorenyl or dibenzofuranyl. The difference is that in the compounds provided by the present invention, a phenyl group is further introduced at the 3'-position of the substituent dibenzofuranyl. Correspondingly, the voltage of each green light device embodiment is reduced to a certain extent compared with Comparative Example 1 and Comparative Example 2, which can be attributed to the extension of the electron-withdrawing dibenzofuranyl conjugation, which enhances the DA interaction within the molecule and further enhances the hole mobility of the molecule; further, the power efficiency of the device is improved to a certain extent as the device voltage decreases. The life of the device is improved by at least 20.4%, which can be attributed to the fact that the extended conjugation of the dibenzofuranyl enhances the ability of the molecule to resist electrons or high-energy excitons. For the comparative example compound C3, the difference from the compound provided by the present invention is that the substituted dibenzofuranyl is further substituted by a third dibenzofuranyl, the three dibenzofuranyl groups are superimposed and the overall electron-withdrawing property is too strong, and the conjugation of the other two aromatic groups of the triarylamine is too short (phenyl), so the stability of the molecule is not as good as that of the molecule provided by the present invention. From the green light device embodiments 1 to 12 in Table 4-2 and the green light device embodiments 13 to 24 in Table 4-3, the power efficiency of the green light device embodiments 1 to 12 is higher than that of the green light device embodiments 13 to 24.

[0247] 6. Combining Table 6-1, Table 6-2 and Table 6-3, for blue light devices, the device performance is similar to that of green light devices, that is, the voltage and power efficiency are reduced and improved to a certain extent, respectively, while the life span is greatly improved. From the blue light device embodiments 1 to 6 in Table 6-2 and the green light device embodiments 7 to 15 in Table 6-3, the power efficiency of green light device embodiments 1 to 6 is slightly higher than that of green light device embodiments 13 to 24.

[0248] In summary, the present invention effectively overcomes various shortcomings of the prior art and has high industrial utilization value.

[0249] The above is only a preferred embodiment of the present invention, and is not any formal or substantial limitation of the present invention. It should be pointed out that ordinary technicians in this technical field can make several improvements and supplements without departing from the method of the present invention, and these improvements and supplements should also be regarded as the protection scope of the present invention. Any technician familiar with this profession, without departing from the spirit and scope of the present invention, can make some changes, modifications and evolutions of the technical content disclosed above, which are equivalent embodiments of the present invention; at the same time, any changes, modifications and evolutions of any equivalent changes made to the above embodiments based on the essential technology of the present invention are still within the scope of the technical solution of the present invention.

Claims

1. A triarylamine compound, characterized in that: The triarylamine compound has a structure as shown in formula (a): wherein Z is selected from O, C(CH3)2 or C(CD3)2; R1 to R3 are the same as or different from each other and are independently selected from hydrogen, deuterium or a group described by formula (b): Among them, one of R4 and R5 serves as a bonding site and bonds to formula (a); Formula (a) satisfies the following conditions: R1, R2, and R3 have only one selected from the group described in formula (b); Ar1 and Ar2 are each independently selected from a substituted or unsubstituted aryl group having 6 to 24 carbon atoms and a substituted or unsubstituted heteroaryl group having 3 to 24 carbon atoms.

2. The triarylamine compound according to claim 1, characterized in that Z is selected from C(CH3)2 or C(CD3)2.

3. The triarylamine compound according to claim 1, characterized in that Z is selected from O.

4. The triarylamine compound according to claim 1 or 2, characterized in that: The triarylamine compound is selected from any one of the following structures: In the above chemical formulas, Ar1 and Ar2 have the same meanings as in claim 1; Optionally, in the above chemical formulas, any hydrogen atom can be replaced by deuterium.

5. The triarylamine compound according to claim 1 or 3, characterized in that: The triarylamine compound is selected from any one of the following structures: In the above chemical formulas, Ar1 and Ar2 have the same meanings as in claim 1; Optionally, in the above chemical formulas, any hydrogen atom can be replaced by deuterium.

6. The triarylamine compound according to claim 1, characterized in that: Ar1 and Ar2 are each independently selected from a substituted or unsubstituted aryl group having 6 to 20 carbon atoms and a substituted or unsubstituted heteroaryl group having 3 to 20 carbon atoms.

7. A triarylamine compound according to claim 1, characterized in that: Ar1, Ar2 are selected from the following substituted or unsubstituted groups: phenyl, biphenyl, naphthyl, phenanthryl, fluorenyl, 9,9'-dimethylfluorenyl, 9,9'-diphenylfluorenyl, spirofluorenyl, spirofluorenyl, carbazolyl, dibenzothienyl, dibenzofuranyl, benzofluorenyl, benzospirofluorenyl, benzonaphthothienyl, and benzonaphthofuranyl.

8. The triarylamine compound according to claim 1, characterized in that: The hydrogen atom at any position in formula (a) and / or formula (b) may be substituted by deuterium.

9. A triarylamine compound according to any one of claims 1, 6 and 7, characterized in that: The substituent in the "substituted or unsubstituted" is selected from deuterium, alkyl or deuterated alkyl having 1 to 6 carbon atoms, cycloalkyl having 3 to 10 carbon atoms, phenyl, naphthyl, phenanthryl, methylphenyl, tert-butylphenyl, 9,9-dimethylfluorenyl, 9,9-diphenylfluorenyl, dibenzofuranyl, dibenzothienyl, benzonaphthothienyl, and benzonaphthofuranyl.

10. The triarylamine compound according to any one of claims 1, 4, 6 to 8, characterized in that: The triarylamine compound is selected from any one of the following:

11. The triarylamine compound according to any one of claims 1, 5, 6 to 8, characterized in that: The triarylamine compound is selected from any one of the following: 12 . A functional layer comprising the triarylamine compound according to claim 1 .

13. Use of the triarylamine compound according to any one of claims 1 to 11 and / or the functional layer according to claim 12 in an organic electroluminescent device.

14. An organic electroluminescent device comprising a first electrode, a second electrode and the functional layer according to claim 12, wherein: The functional layer is at least one of a hole injection layer, a hole transport layer, an electron blocking layer, a light emitting layer, an electron injection layer or an electron transport layer.

15. A display or lighting device comprising the organic electroluminescent device according to claim 14.

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