Boron-nitrogen compound and organic electroluminescent device

Abstract

The invention provides a boron-nitrogen compound and an organic electroluminescent device. The boron-nitrogen compound has a structure as shown in a formula I. By designing the structure of the boron-nitrogen compound, the compound which is excellent in performance and suitable for being used as a luminescent material is prepared, and the organic electroluminescent device prepared from the boron-nitrogen compound has relatively high current efficiency and relatively long service life.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of organic light-emitting materials, and particularly relates to a boron-nitrogen compound and an organic electroluminescent device. BACKGROUND

[0002] With the continuous progress and development of social science, display technology has become crucial in people's lives. Organic electroluminescent diodes (OLEDs) have become one of the mainstream display devices due to their flexibility, bendability, self-luminescence, high contrast, large size, low power consumption and many other advantages.

[0003] The luminescence mechanism of OLEDs is that electrons and holes recombine to form excitons under electric excitation, and excitons obey probability statistics distribution, with about 25% of singlet excitons and about 75% of triplet excitons. The first generation of luminescence technology is collectively referred to as fluorescent technology, which utilizes singlet excitons to emit light; the second generation of luminescence technology is collectively referred to as phosphorescent technology, which utilizes triplet excitons to emit light, and theoretically can achieve 100% internal quantum efficiency, but the heavy metals required for constructing phosphorescent dyes are not only expensive but also pollute the environment, so the third generation of thermally activated delayed fluorescence technology constructed by organic small molecules is currently widely used. When the singlet-triplet energy level difference is very small, triplet excitons can undergo reverse intersystem crossing to singlet, and then back to the ground state to emit light. Among them, red and green dyes as three primary colors have high electroluminescent efficiency and low power consumption, and have become the mainstream of current commercial display devices. However, the chromaticity and lifetime of blue light materials cannot meet the current commercial display requirements, and traditional fluorescent materials are still used in blue devices to achieve high color purity and long device lifetime.

[0004] In recent years, the research group of Takuji Hatakeyama and Junji Kido of Japan reported a series of organic small molecule materials DABNA-1 based on boron-nitrogen resonance type thermally activated delayed fluorescence (Adv. Mater. 2016, 28, 2777-2781 J. Mater. Chem. C, 2019, 7, 3082-3089). In this compound, boron atoms, nitrogen atoms and phenyl groups form a rigid polycyclic aromatic resonance skeleton, so it has a high fluorescence quantum yield. Compared with traditional blue fluorescent dyes, this compound has a narrower emission spectrum band gap and higher color purity. However, the rigid planar structure also leads to a large singlet-triplet energy level difference, and the reverse intersystem crossing from triplet to singlet is slow. After the excitons recombine on the dye, it will cause serious efficiency roll-off and short device lifetime. In addition, the excessively planar rigid structure often leads to the emission spectrum being widened and red-shifted due to too high doping concentration.

[0005]

[0006] There is still a great room for improvement in the light-emitting performance of the existing organic electroluminescent materials, and the industry urgently needs to develop new light-emitting material systems to meet the commercialization needs. Boron-nitrogen resonance materials have the advantages of high color purity and high light-emitting efficiency, which have attracted widespread attention from the scientific research and industrial communities. However, due to the little influence of the peripheral substituent group on the energy level, it is difficult to control the light-emitting color of the material, and the light color has been limited in the sky blue light region, which greatly limits the further application of such materials in high-resolution display, full-color display, and white light illumination fields.

[0007] With the gradual entry of OLED products into the market, people have higher and higher requirements for the performance of such products. The current OLED materials and device structures cannot completely solve the problems of OLED product efficiency, service life, cost and the like. Therefore, how to provide a new organic electroluminescent material has become a technical problem to be solved at present. SUMMARY

[0008] In view of the deficiencies of the prior art, the purpose of the present application is to provide a boron-nitrogen compound and an organic electroluminescent device. The present application designs the structure of the boron-nitrogen compound, and prepares a compound with excellent performance suitable for use as a light-emitting material. The organic electroluminescent device prepared from the boron-nitrogen compound has high current efficiency and long service life.

[0009] To achieve this purpose, the present application adopts the following technical solutions:

[0010] In a first aspect, the present application provides a boron-nitrogen compound, which has the following structure shown in formula I:

[0011]

[0012] wherein Ar1 and Ar2 are independently selected from one of substituted or unsubstituted C6-C60 aryl group, substituted or unsubstituted C3-C60 heteroaryl group;

[0013] ring A, ring D and ring C are independently selected from any one of substituted or unsubstituted C6-C20 aromatic ring, substituted or unsubstituted C7-C30 heteroaromatic ring containing at least one of oxygen atom, sulfur atom or nitrogen atom (and the C7-C30 heteroaromatic ring containing at least one of oxygen atom, sulfur atom or nitrogen atom is free of boron atom), wherein at least one of ring A and ring D is selected from the structure shown in formula a, and the dotted line represents the fusion site of the structure shown in formula a;

[0014]

[0015] wherein U1, U2, U3, U4are independently selected from N or CR', and R' is independently selected from any one of hydrogen, halogen, cyano, substituted or unsubstituted C1-C20 linear or branched alkyl, substituted or unsubstituted C3-C20 cycloalkyl, substituted or unsubstituted C6-C30 aryl, substituted or unsubstituted C3-C30 heteroaryl;

[0016] ring A, ring D, ring C contains at least one group having the structure shown in formula 2 (i.e. at least one of ring A, ring D, ring C is substituted by a group having the structure shown in formula 2), the group having the structure shown in formula 2 is not fused with ring A, ring D, ring C, and is not connected with Ar1or Ar2(the group having the structure shown in formula 2 is not fused with ring A, ring D, ring C means that ring A, ring D, ring C can only be connected with the group having the structure shown in formula 2 through the dotted line single bond, and is not connected with other sites in Ar1or Ar2), the dotted line represents the connecting site of the group;

[0017]

[0018] wherein X1is selected from any one of NR2, O, S or CR3R4, and if X1is selected from NR2or CR3R4, the group having the structure shown in formula 2 is connected with ring A, ring D, ring C; and if X1is selected from O or S, the group having the structure shown in formula 2 is connected with ring C;

[0019] Z1, Z2, Z3, Z4are independently selected from N or CR";

[0020] m represents any integer from 0 to 6;

[0021] R1is independently selected from any one of halogen, cyano, substituted or unsubstituted C1-C20 linear or branched alkyl, substituted or unsubstituted C3-C20 cycloalkyl, substituted or unsubstituted C1-C20 alkoxy, substituted or unsubstituted C1-C20 alkylsilyl, substituted or unsubstituted C1-C20 alkylthio, substituted or unsubstituted C6-C30 arylamino, substituted or unsubstituted C3-C30 heteroarylamino, substituted or unsubstituted C6-C30 aryloxy, substituted or unsubstituted C3-C30 heteroaryloxy, substituted or unsubstituted C6-C30 arylthio, substituted or unsubstituted C6-C30 arylsilyl, substituted or unsubstituted C6-C30 aryl, substituted or unsubstituted C3-C30 heteroaryl;

[0022] when m is equal to or greater than 2, R1are the same or different, and any adjacent two R1are not connected or connected by a single bond;

[0023] R2is selected from any one of a single bond, hydrogen, substituted or unsubstituted C6-C30 aryl, substituted or unsubstituted C3-C30 heteroaryl;

[0024] R3, R4, R" are each independently selected from any one of hydrogen, halogen, cyano, substituted or unsubstituted C1-C20 linear or branched alkyl, substituted or unsubstituted C3-C20 cycloalkyl, substituted or unsubstituted C1-C20 alkoxy, substituted or unsubstituted C1-C20 alkylsilyl, substituted or unsubstituted C1-C20 alkylthio, substituted or unsubstituted C6-C30 arylamino, substituted or unsubstituted C3-C30 heteroarylamino, substituted or unsubstituted C6-C30 aryloxy, substituted or unsubstituted C3-C30 heteroaryloxy, substituted or unsubstituted C6-C30 arylthio, substituted or unsubstituted C6-C30 arylsilyl, substituted or unsubstituted C6-C30 aryl, substituted or unsubstituted C3-C30 heteroaryl;

[0025] the substituents of the substituents of Ar1, Ar2, ring A, ring D, ring C, R', R", R1, R2, R3, R4 are each independently selected from halogen, cyano, unsubstituted or R a substituted C1-C30 linear or branched alkyl, unsubstituted or R a substituted C1-C30 alkoxy, unsubstituted or R a substituted C1-C30 alkylthio, unsubstituted or R a substituted C3-C30 cycloalkyl, unsubstituted or R a substituted C6-C30 aryl, unsubstituted or R a substituted C3-C30 heteroaryl, unsubstituted or R a substituted C6-C30 aryloxy, unsubstituted or R a substituted C6-C30 arylthio, unsubstituted or R a substituted C1-C30 alkylsilyl, unsubstituted or R a substituted C6-C30 arylsilyl, unsubstituted or R a substituted C6-C30 arylamino;

[0026] R a are each independently selected from at least one of halogen, cyano, C6-C20 aryl, C3-C20 heteroaryl, unsubstituted or halogenated C1-C10 linear or branched alkyl;

[0027] any two adjacent of ring A, ring D, ring C, Ar1, Ar2 are not connected or connected by a single bond.

[0028] The present application designs the structure of boron-nitrogen compounds, and prepares a compound with excellent performance and suitable for a light-emitting material. An organic electroluminescent device prepared from the boron-nitrogen compound has high current efficiency and long service life.

[0029] In the present application, the substituent of formula (2) is combined with the BN core, which has multiple resonance effects, is beneficial to improve the light-emitting efficiency and realize narrow-spectrum fluorescent emission, and limits different formula (2) to be connected with ring C when X1 is O or S, so as to reduce the triplet energy level of the molecule without changing the characteristics of narrow-spectrum emission, thereby improving the device lifetime.

[0030] It should be noted that when R2 is selected from a single bond, the connection site of the group represented by formula 2 is the N atom.

[0031] It should be noted that in the present application, the possible effects of each group / feature are described separately for the sake of convenience, but this does not mean that these groups / features act independently. In fact, the reason for good performance is essentially the optimized combination of the whole molecule, which is the result of the synergistic effect between groups, rather than the effect of a single group.

[0032] In the present application, if not specially stated, the description of chemical elements includes the concept of isotopes with the same chemical properties, for example, hydrogen (H) includes 1H (protium), 2H (deuterium, D), 3H (tritium, T), etc.; carbon (C) includes 12C, 13C, etc.

[0033] In the present application, unless otherwise specified, the heteroatom of the heteroaryl group is selected from N, O, S atoms or atom groups.

[0034] In the present application, the expression of the ring structure with “—” or “------” indicates that the connection site is at any position on the ring structure that can form a bond.

[0035] In the present application, the expression of Ca-Cb represents that the group has a carbon atom number of a-b, and unless otherwise specified, in general, the carbon atom number does not include the carbon atom number of the substituent.

[0036] In the present application, “independently” means that when the subject has multiple, they can be the same or different.

[0037] In the present application, the C6-C60 aryl group can be a C6, C9, C10, C12, C14, C16, C18, C20, C22, C24, C26, C28, C30, C36, C42, C48, C50, C54, or C60 aryl group, and preferably a C6-C20 aryl group, including a monocyclic aryl group or a fused ring aryl group. The monocyclic aryl group means a group containing at least one phenyl group, and when there are at least two phenyl groups, the phenyl groups are connected by a single bond, and examples include, but are not limited to, a phenyl group, a biphenyl group, a terphenyl group, and the like. The fused ring aryl group means a group containing at least two aromatic rings, and the aromatic rings are fused to each other by sharing two adjacent carbon atoms, and examples include, but are not limited to, a naphthyl group, a naphthylphenyl group, a phenylnaphthyl group, an anthryl group, a phenanthryl group, an indenyl group, a fluorenyl group, derivatives thereof (a 9,9-dimethylfluorenyl group, a 9,9-diphenylfluorenyl group, a 9,9-dinaphthylfluorenyl group, a spirobifluorenyl group, a benzofluorenyl group, and the like), a fluoranthenyl group, a triphenylenyl group, a pyrenyl group, a perylenyl group, a tetracenyl group, and the like. The above-listed groups include all possible connection modes thereof.

[0038] In the present application, the C3-C60 heteroaryl group can be a C3, C4, C5, C6, C9, C10, C12, C14, C16, C18, C20, C22, C24, C26, C28, C30, C36, C42, C48, C50, C54, or C60 heteroaryl group, and preferably a C6-C20 heteroaryl group, including a monocyclic heteroaryl group or a fused ring heteroaryl group. The monocyclic heteroaryl group means a group containing at least one heteroaryl group, and when there is one heteroaryl group and other groups (such as an aryl group, a heteroaryl group, an alkyl group, and the like) in the molecule, the heteroaryl group and the other groups are connected by a single bond, and examples include, but are not limited to, a furanyl group, a thiophenyl group, a pyrrolyl group, a pyridyl group, a pyrazinyl group, a pyrimidinyl group, a pyridazinyl group, a triazinyl group, an oxazolyl group, a thiazolyl group, an imidazolyl group, and the like. The fused ring heteroaryl group means a group containing at least one aromatic heterocycle and one aromatic ring (aromatic heterocycle or aromatic ring) in the molecule, and the two groups are fused to each other by sharing two adjacent atoms, and examples include, but are not limited to, a benzofuranyl group, a benzothiophenyl group, an isobenzofuranyl group, an isobenzothiophenyl group, an indolyl group, a dibenzofuranyl group, a dibenzothiophenyl group, a carbazolyl group, derivatives thereof (an N-phenylcarbazolyl group, an N-naphthylcarbazolyl group, a benzocarbazolyl group, a diphenylcarbazolyl group, an indolocarbazolyl group, an azacarbazolyl group, and the like), an acridinyl group, a phenoxazinyl group, a quinolinyl group, an isoquinolinyl group, a quinoxalinyl group, a quinazolinyl group, a pyridopyrimidinyl group, a pyridopyrazinyl group, and the like. The above-listed groups include all possible connection modes thereof.

[0039] ​In the present application, the C6-C20 aryl group can be C6, C9, C10, C12, C14, C16, C18 or C20 aryl group, including monocyclic aryl group or fused ring aryl group. The monocyclic aryl group means that the group contains at least one phenyl group, and when containing at least two phenyl groups, the phenyl groups are connected by a single bond, and exemplarily includes but is not limited to phenyl, biphenyl, terphenyl and the like; the fused ring aryl group means that the group contains at least two aromatic rings, and the aromatic rings are fused to each other by sharing two adjacent carbon atoms, and exemplarily includes but is not limited to naphthyl, naphthylphenyl, phenylnaphthyl, anthryl, phenanthryl, indenyl, 9,9-dimethylfluorenyl, fluoranthene, triphenylene and the like; the above-mentioned groups include all possible connection modes thereof.

[0040] In the present application, the C3-C15 heteroaryl group can be C3, C4, C5, C6, C9, C10, C12 or C15 heteroaryl group, including monocyclic heteroaryl group or fused ring heteroaryl group. The monocyclic heteroaryl group means that the molecule contains at least one heteroaryl group, and when the molecule contains one heteroaryl group and other groups (such as aryl group, heteroaryl group, alkyl group and the like), the heteroaryl group and the other groups are connected by a single bond, and exemplarily includes but is not limited to furanyl, thienyl, pyrrolyl, pyridyl, pyrazinyl, pyrimidinyl, pyridazinyl, triazinyl, oxazolyl, thiazolyl, imidazolyl and the like. The fused ring heteroaryl group means that the molecule contains at least one aromatic heterocycle and one aromatic ring (aromatic heterocycle or aromatic ring), and the two are fused to each other by sharing two adjacent atoms, and exemplarily includes but is not limited to benzofuranyl, benzothienyl, dibenzofuranyl, dibenzothienyl, carbazolyl and the like; the above-mentioned groups include all possible connection modes thereof.

[0041] In the present application, the C1-C20 straight chain or branched chain alkyl group can be C2, C3, C4, C5, C6, C7, C8, C9, C10, C11, C12, C13, C14, C15, C16, C17, C18 or C20 straight chain or branched chain alkyl group, preferably C1-C10 straight chain or branched chain alkyl group, more preferably C1-C6 straight chain or branched chain alkyl group; exemplarily includes but is not limited to methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, tert-butyl, n-pentyl, isopentyl, neopentyl, n-hexyl, n-octyl, n-heptyl, n-nonyl or n-decyl and the like.

[0042] In the present application, the C3-C20 cycloalkyl group can be C4, C5, C6, C7, C8, C9, C10, C11, C12, C13, C14, C15, C16, C17, C18 or C20 cycloalkyl group, preferably C3-C10 cycloalkyl group; exemplarily includes but is not limited to cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, adamantyl and the like.

[0043] In the present application, C6-C12 aryl exemplarily includes, but is not limited to, phenyl, naphthyl, or biphenyl.

[0044] In the present application, specific examples of the C1-C20 (e.g., C2, C3, C4, C5, C6, C7, C8, C9, C10, C11, C12, C13, C14, C15, C16, C17, C18, or C20, etc.) alkoxy group can be exemplified by a monovalent group obtained by connecting the above examples of the straight-chain or branched alkyl group with O.

[0045] In the present application, the C1-C20 (e.g., C2, C3, C4, C5, C6, C7, C8, C9, C10, C11, C12, C13, C14, C15, C16, C17, C18, or C20, etc.) alkylsilyl group, which is a monovalent group formed by substituting at least one H on -SiH3 with the above-listed straight-chain or branched alkyl group, exemplarily includes, but is not limited to, methylsilyl, ethylsilyl, etc.

[0046] In the present application, specific examples of the C1-C10 (e.g., C2, C3, C4, C5, C6, C7, C8, C9, or C10, etc.) alkylthio group can be exemplified by a monovalent group obtained by connecting the above examples of the straight-chain or branched alkyl group with S.

[0047] In the present application, the C1-C30 straight-chain or branched alkyl group can be a straight-chain or branched alkyl group of C2, C3, C4, C5, C6, C7, C8, C9, C10, C11, C12, C13, C14, C15, C16, C17, C18, C20, C22, C24, C26, or C28, etc., preferably a C1-C20 straight-chain or branched alkyl group, and further preferably a C1-C10 straight-chain or branched alkyl group; and exemplarily includes, but is not limited to, methyl, ethyl, propyl, isopropyl, n-butyl, isobutyl, t-butyl, n-pentyl, isopentyl, neopentyl, n-hexyl, n-octyl, n-heptyl, n-nonyl, or n-decyl, etc.

[0048] Specific examples of the C1-C30 (e.g., C2, C3, C4, C5, C6, C7, C8, C9, C10, C11, C12, C13, C14, C15, C16, C17, C18, C20, C22, C24, C26, or C28, etc.) alkoxy group can be exemplified by a monovalent group obtained by connecting the above examples of the straight-chain or branched alkyl group with O. Specific examples of the C1-C30 (e.g., C2, C3, C4, C5, C6, C7, C8, C9, C10, C11, C12, C13, C14, C15, C16, C17, C18, C20, C22, C24, C26, or C28, etc.) alkylthio group can be exemplified by a monovalent group obtained by connecting the above examples of the straight-chain or branched alkyl group with S.

[0049] In the present application, the C3-C30 cycloalkyl group can be a C4, C5, C6, C7, C8, C9, C10, C11, C12, C13, C14, C15, C16, C17, C18, C20, C22, C24, C26, or C28 cycloalkyl group, for example, and includes, but is not limited to, a cyclopropyl group, a cyclobutyl group, a cyclopentyl group, a cyclohexyl group, an adamantyl group, and the like.

[0050] In the present application, the C6-C30 aryl group can be a C6, C9, C10, C12, C14, C16, C18, C20, C22, C24, C26, or C28 aryl group, preferably a C6-C20 aryl group, and includes a monocyclic aryl group or a fused ring aryl group. The monocyclic aryl group means a group containing at least one phenyl group, and when there are at least two phenyl groups, the phenyl groups are connected by a single bond, and includes, for example, but is not limited to, a phenyl group, a biphenyl group, a terphenyl group, and the like. The fused ring aryl group means a group containing at least two aromatic rings, and the aromatic rings are fused to each other by sharing two adjacent carbon atoms, and includes, for example, but is not limited to, a naphthyl group, a naphthylphenyl group, a phenylnaphthyl group, an anthryl group, a phenanthryl group, an indenyl group, a fluorenyl group, derivatives thereof (a 9,9-dimethylfluorenyl group, a 9,9-diphenylfluorenyl group, a 9,9-dinaphthylfluorenyl group, a spirobifluorenyl group, a benzofluorenyl group, and the like), a fluoranthenyl group, a triphenylenyl group, a pyrenyl group, a perylenyl group, a tetracene group, and the like. The above-listed groups include all possible connection modes thereof.

[0051] In the present application, the C3-C30 heteroaryl group can be a C3, C4, C5, C6, C9, C10, C12, C14, C16, C18, C20, C22, C24, C26, or C28 heteroaryl group, and includes a monocyclic heteroaryl group or a fused ring heteroaryl group. The monocyclic heteroaryl group means a group containing at least one heteroaryl group in a molecule, and when there is one heteroaryl group and other groups (such as an aryl group, a heteroaryl group, an alkyl group, and the like) in the molecule, the heteroaryl group and the other groups are connected by a single bond, and includes, for example, but is not limited to, a furanyl group, a thiophenyl group, a pyrrolyl group, a pyridyl group, a pyrazinyl group, a pyrimidinyl group, a pyridazinyl group, a triazinyl group, an oxazolyl group, a thiazolyl group, an imidazolyl group, and the like. The fused ring heteroaryl group means a group containing at least one aromatic heterocycle and one aromatic ring (aromatic heterocycle or aromatic ring) in a molecule, and the two groups are fused to each other by sharing two adjacent atoms, and includes, for example, but is not limited to, a benzofuranyl group, a benzothiophenyl group, an isobenzofuranyl group, an isobenzothiophenyl group, an indolyl group, a dibenzofuranyl group, a dibenzothiophenyl group, a carbazolyl group, derivatives thereof (an N-phenylcarbazolyl group, an N-naphthylcarbazolyl group, a benzocarbazolyl group, a diphenylcarbazolyl group, an indolocarbazolyl group, an azacarbazolyl group, and the like), an acridinyl group, a phenoxazinyl group, a quinolyl group, an isoquinolyl group, a quinoxalyl group, a quinazolyl group, a pyridopyrimidinyl group, a pyridopyrazinyl group, and the like. The above-listed groups include all possible connection modes thereof. ​

[0052] In the present application, specific examples of the C6-C30 (e.g., C6, C9, C10, C12, C14, C16, C18, C20, C22, C24, C26, C28, or C30, etc.) aryloxy group, which is a monovalent group obtained by linking the above-mentioned examples of the aryl group with O, include, but are not limited to, for example, phenyloxy, biphenylyloxy, naphthalyloxy, etc.

[0053] In the present application, specific examples of the C6-C30 (e.g., C6, C9, C10, C12, C14, C16, C18, C20, C22, C24, C26, C28, or C30, etc.) arylamino group, which is a group formed by substituting at least one H on -NH2with the above-mentioned examples of the aryl group, include, but are not limited to, for example, phenylamino, biphenylamino, naphthylamino, etc.

[0054] In the present application, specific examples of the C3-C30 (e.g., C3, C4, C5, C6, C9, C10, C12, C14, C16, C18, C20, C22, C24, C26, C28, or C30, etc.) heteroarylamino group, which is a group formed by substituting at least one H on -NH2with the above-mentioned examples of the heteroaryl group, include, but are not limited to, for example, pyrrolylamino, pyrimidinylamino, furanylamino, etc.

[0055] In the present application, specific examples of the C1-C30 (e.g., C2, C3, C4, C5, C6, C7, C8, C9, C10, C11, C12, C13, C14, C15, C16, C17, C18, C20, C22, C24, C26, or C28, etc.) alkylsilyl group, which is a monovalent group formed by substituting at least one H on -SiH3with the above-mentioned examples of the straight-chain or branched-chain alkyl group, include, but are not limited to, for example, methylsilyl, ethylsilyl, etc. Specific examples of the C6-C30 (e.g., C6, C9, C10, C12, C14, C16, C18, C20, C22, C24, C26, or C28, etc.) arylsilyl group, which is a monovalent group formed by substituting at least one H on -SiH3with the above-mentioned examples of the aryl group.

[0056] In the present application, the C1-C10 straight-chain or branched-chain alkyl group can be a straight-chain or branched-chain alkyl group having 2, 3, 4, 5, 6, 7, 8, 9, or 10 carbon atoms, and include, but are not limited to, for example, methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, t-butyl, n-pentyl, isopentyl, neopentyl, n-hexyl, n-octyl, n-heptyl, n-nonyl, n-decyl, etc.

[0057] In the present application, the halogen includes fluorine, chlorine, bromine or iodine; the same meaning is included when the same is described hereinafter.

[0058] In the present application, the "halogenated" means that at least one H in the group is replaced by halogen (fluorine, chlorine, bromine or iodine).

[0059] The following are preferred technical solutions of the present application, but not as a restriction on the technical solutions provided by the present application, through the following preferred technical solutions, the purpose and beneficial effects of the present application can be better achieved and realized.

[0060] Preferably, the group represented by formula 2 includes a group represented by formula 2-1 or formula 2-2, and the dotted line represents the connection site of the group:

[0061]

[0062] The group represented by formula 2-1 is connected with ring A, ring D and ring C;

[0063] X 11 selected from NR 21 , O, S or CR 31 R 41 , when X 11 selected from NR 21 or CR 31 R 41 , the group represented by formula 2-2 is connected with ring A, ring D and ring C; when X 11 selected from O or S, the group represented by formula 2-2 is connected with ring C;

[0064] R 21 selected from any one of unsubstituted or C1-C10 (such as C1, C2, C3, C4, C5, C6, C7, C8, C9 or C10) straight chain or branched chain alkyl substituted C6-C12 (such as C6, C10 or C12, etc.) aryl, unsubstituted or C1-C10 (such as C1, C2, C3, C4, C5, C6, C7, C8, C9 or C10) straight chain or branched chain alkyl substituted C3-C12 (such as C3, C6 or C10, etc.) heteroaryl;

[0065] R 11 -R 14 , R 31 , R 41each independently selected from the group consisting of hydrogen, halogen (e.g., fluorine, chlorine, or bromine), cyano, C1-C10 (e.g., C1, C2, C3, C4, C5, C6, C7, C8, C9, or C10) straight chain or branched alkyl, C1-C10 (e.g., C1, C2, C3, C4, C5, C6, C7, C8, C9, or C10) alkoxy, C1-C10 (e.g., C1, C2, C3, C4, C5, C6, C7, C8, C9, or C10) alkylthio, C1-C10 (e.g., C1, C2, C3, C4, C5, C6, C7, C8, C9, or C10) alkylsilyl, C3-C10 (e.g., C3, C4, C5, C6, C7, C8, C9, or C10) cycloalkyl, C6-C12 (e.g., C6, C10, or C12, etc.) aryl, C3-C12 (e.g., C3, C6, or C10, etc.) heteroaryl, C6-C12 (e.g., C6, C10, or C12, etc.) aryloxy, C6-C12 (e.g., C6, C10, or C12, etc.) arylthio, C6-C12 (e.g., C6, C10, or C12, etc.) arylsilyl, C6-C12 (e.g., C6, C10, or C12, etc.) arylamino, C3-C12 (e.g., C3, C6, or C10, etc.) heteroarylamino, or a combination of at least two of any of the foregoing;

[0066] m 11 , m 21 represents any integer from 0 to 4 (e.g., 0, 1, 2, 3, or 4); m 12 , m 22 represents any integer from 0 to 6 (e.g., 0, 1, 2, 3, 4, 5, or 6);

[0067] m 11 when greater than or equal to 2, R 11 , each independently, R 11 are not connected or are connected by a single bond (i.e., not an aromatic ring); m 12 when greater than or equal to 2, R 12 , each independently, R 12 are not connected or are connected by a ring (an ester ring or an aromatic ring); m 21 when greater than or equal to 2, R 13 , each independently, R 13 are not connected or are connected by a single bond (i.e., not an aromatic ring); m 22 when greater than or equal to 2, R 14 , each independently, R 14 are not connected or are connected by a ring (an ester ring or an aromatic ring).

[0068] Specifically, the group represented by Formula 2-2 includes a group represented by any one of Formulas 2-2-1 to 2-2-3, with the dotted line representing the connection site of the group:

[0069]

[0070] In Formula 2-2-1, m 21 represents any integer from 0 to 3 (e.g., 0, 1, 2, or 3); m 22 represents any integer from 0 to 6 (e.g., 0, 1, 2, 3, 4, 5, or 6); m 21 R 13 R 13 are the same as or different from each other, and are not connected or are single-bonded; m 22 R 14 R 14 are the same as or different from each other, and are not connected or are ring-bonded.

[0071] In Formula 2-2-2, Formula 2-2-3, m 21 represents any integer from 0 to 4 (e.g., 0, 1, 2, 3, or 4); m 22 represents any integer from 0 to 5 (e.g., 0, 1, 2, 3, 4, or 5); m 21 R 13 R 13 are the same as or different from each other, and are not connected or are single-bonded; m 22 R 14 R 14 are the same as or different from each other, and are not connected or are ring-bonded.

[0072] R 21 is selected from one of phenyl, naphthyl, methylphenyl, t-butylphenyl, and pyridyl.

[0073] R 11 -R 14 , R 31 , R 41 are each independently selected from one or a combination of at least two of hydrogen, halogen, cyano, methyl, ethyl, propyl, isopropyl, t-butyl, isopentyl, 2,2,5,5-tetramethylhexyl, cyclohexyl, phenyl, naphthyl, pyridyl, methoxy, methylthio, trimethylsilyl, triphenylsilyl, dimethylethylsilyl, diphenylamino, dipyridylamino, phenoxy, phenylthio, and fluorenyl.

[0074] Preferably, the group represented by Formula 2 is selected from any one of the following groups:

[0075]

[0076]

[0077]

[0078] wherein the dotted line represents the point of attachment of the group.

[0079] Preferably, the ring C is selected from the structure shown in formula b, and the dotted line represents the point of fusion of the structure shown in formula b:

[0080]

[0081] wherein Y1, Y2, Y3are independently selected from CR5or N;

[0082] R5is independently selected from hydrogen, C1-C10(e.g., C1, C2, C3, C4, C5, C6, C7, C8, C9, or C10) straight or branched chain alkyl, C3-C10(e.g., C3, C4, C5, C6, C7, C8, C9, or C10) cycloalkyl, C6-C20(e.g., C6, C10, C12, C15, C18, or C20) aryl, C3-C15(e.g., C6, C10, C12, or C15, etc.) heteroaryl, any one of the groups shown in formula 2, or a combination of at least two of them.

[0083] More preferably, Y2is selected from CR5; and R5is selected from the group shown in formula 2, in which case the compound has higher efficiency and lifetime.

[0084] Preferably, the boron-nitrogen compound has the structure shown in formula I-1:

[0085]

[0086] wherein Y1, Y2, Y3have the same definition as Y1, Y2, Y3in formula b;

[0087] Ring A, ring D, Ar1, Ar2have the same definition as ring A, ring D, Ar1, Ar2in formula I.

[0088] Preferably, at most one of Y1, Y2, Y3is N.

[0089] Preferably, the ring C is selected from the dotted line represents the point of fusion of

[0090] n1represents any integer from 0 to 3 (e.g., 0, 1, 2, or 3); when n1is greater than or equal to 2, R 51 are the same as or different from each other; R51is independently selected from H, C1-C10(e.g., C1, C2, C3, C4, C5, C6, C7, C8, C9, or C10) straight or branched chain alkyl, any one of the groups shown in formula 2.

[0091] Preferably, the ring A and ring D are independently selected from a substituted or unsubstituted C6-C12 aryl ring or a substituted or unsubstituted C7-C12 heteroaryl ring containing at least one of oxygen atom, sulfur atom or nitrogen atom, wherein at least one of the ring A, ring D is selected from the structure shown in formula a.

[0092] Preferably, the ring A and ring D are independently selected from the structure shown in formula a or formula a-1, at least one of the ring A, ring D is selected from the structure shown in formula a, and the dotted line represents a fused site of the structure shown in formula a or formula a-1.

[0093]

[0094] wherein X is selected from O or S;

[0095] U1, U2, U3, U4 have the same definition as described above.

[0096] U5, U6, U7, U8 are independently selected from N or CR', and R' has the same definition as formula a.

[0097] Preferably, the boron-nitrogen compound has the structure shown in formula I-2 or I-3 as follows:

[0098]

[0099] wherein in formula I-2, U1, U2, U3, U4 have the same definition as formula a;

[0100] in formula I-3, has the same definition as formula a, formula a-1;

[0101] Y1, Y2, Y3 have the same definition as formula b;

[0102] Ar1, Ar2 have the same definition range as formula I.

[0103] Preferably, the boron-nitrogen compound has the structure shown in formula I-2 as follows.

[0104] Preferably, the ring A and ring D are independently selected from the dotted line represents a fused site;

[0105] n2, n3 each independently represent any integer from 0 to 4 (e.g., 0, 1, 2, 3, or 4); when n2 is equal to or greater than 2, R6's are the same or different from each other; when n3 is equal to or greater than 2, R7's are the same or different from each other; each of R6, R7 is independently selected from hydrogen, halogen, cyano, C1-C6 (e.g., C1, C2, C3, C4, C5, or C6) straight or branched chain alkyl, C3-C6 (e.g., C3, C4, C5, or C6) cycloalkyl, C6-C20 (e.g., C6, C10, C12, C15, C18, or C20, etc.) aryl, or any one of the groups represented by Formula 2, further preferably hydrogen, halogen, cyano, methyl, ethyl, propyl, isopropyl, t-butyl, isoamyl, cyclohexyl, phenyl, naphthyl, any one of the groups represented by Formula 2;

[0106] Preferably, ring A is selected from n2 represents any integer from 0 to 4 (e.g., 0, 1, 2, 3, or 4); when n2 is equal to or greater than 2, R6's are the same or different from each other; each of R6 is independently selected from hydrogen, halogen, cyano, C1-C6 (e.g., C1, C2, C3, C4, C5, or C6) straight or branched chain alkyl, C3-C6 (e.g., C3, C4, C5, or C6) cycloalkyl, C6-C20 (e.g., C6, C10, C12, C15, C18, or C20, etc.) aryl, or any one of the groups represented by Formula 2, further preferably hydrogen, halogen, cyano, methyl, ethyl, propyl, isopropyl, t-butyl, isoamyl, cyclohexyl, phenyl, naphthyl, any one of the groups represented by Formula 2.

[0107] Preferably, ring D is selected from More preferably selected from n2, n3 each independently represent any integer from 0 to 4 (e.g., 0, 1, 2, 3, or 4); when n2 is equal to or greater than 2, R6's are the same or different from each other; when n3 is equal to or greater than 2, R7's are the same or different from each other; each of R6, R7 is independently selected from hydrogen, halogen, cyano, C1-C6 (e.g., C1, C2, C3, C4, C5, or C6) straight or branched chain alkyl, C3-C6 (e.g., C3, C4, C5, or C6) cycloalkyl, C6-C20 (e.g., C6, C10, C12, C15, C18, or C20, etc.) aryl, or any one of the groups represented by Formula 2, further preferably hydrogen, halogen, cyano, methyl, ethyl, propyl, isopropyl, t-butyl, isoamyl, cyclohexyl, phenyl, naphthyl, any one of the groups represented by Formula 2.

[0108] Preferably, Ar1and Ar2are each independently selected from any one of substituted or unsubstituted C6-20(e.g., C6, C10, C12, C15, C18, or C20, etc.) aryl, substituted or unsubstituted C3-10(e.g., C3, C5, C9, or C10, etc.) heteroaryl, further preferably substituted or unsubstituted phenyl, substituted or unsubstituted biphenyl, substituted or unsubstituted phenylnaphthyl, or substituted or unsubstituted pyridyl;

[0109] The substituents are selected from any one or a combination of at least two of halogen, cyano, C1-C6(e.g., C1, C2, C3, C4, C5, or C6) straight chain or branched alkyl, C6-C12(e.g., C6, C10, or C12, etc.) aryl, further preferably any one of halogen, cyano, methyl, ethyl, propyl, isopropyl, t-butyl, isopropyl, isoamyl, phenyl, or naphthyl.

[0110] Preferably, the boron-nitrogen based compound has any one of the following structures:

[0111]

[0112]

[0113]

[0114]

[0115]

[0116]

[0117] In a second aspect, the present application provides a use of the boron-nitrogen based compound as described in the first aspect in an organic electronic device.

[0118] Preferably, the organic electronic device comprises an organic electroluminescent device, an optical sensor, a solar cell, a lighting element, an organic thin film transistor, an organic field effect transistor, an organic thin film solar cell, an information tag, an electronic artificial skin sheet, a sheet-type scanner, or an electronic paper, further preferably an organic electroluminescent device.

[0119] Preferably, the boron-nitrogen based compound is used in an organic electroluminescent device.

[0120] Preferably, the boron-nitrogen based compound is used as a light-emitting layer dye in an organic electroluminescent device.

[0121] Preferably, the boron-nitrogen based compound is used as a light-emitting dye (also called a dopant material) in an organic electroluminescent device.

[0122] In a third aspect, the present application provides an organic electroluminescent device, comprising a first electrode, a second electrode, and at least one organic layer disposed between the first electrode and the second electrode; the organic layer comprising at least one boron-nitrogen compound as described in the first aspect.

[0123] Preferably, the organic layer comprises a light-emitting layer, and the light-emitting layer comprises at least one boron-nitrogen compound as described in the first aspect.

[0124] Preferably, the light-emitting layer comprises a host material and a dopant material, and the dopant material comprises at least one boron-nitrogen compound as described in the first aspect.

[0125] An organic electroluminescent device (OLED device) comprises a first electrode and a second electrode, and an organic material layer disposed between the electrodes. The organic material layer can be further divided into multiple regions. For example, the organic material layer can comprise a hole transport region, a light-emitting layer, and an electron transport region.

[0126] In specific embodiments, a substrate can be used below the first electrode or above the second electrode. The substrate is a glass or a polymer material having excellent mechanical strength, thermal stability, water resistance, and transparency. In addition, the substrate can also be provided with a thin film transistor (TFT) for display.

[0127] In the present application, one of the first electrode and the second electrode is an anode, and the other is a cathode. For example, the first electrode is an anode, and the second electrode is a cathode, or the first electrode is a cathode, and the second electrode is an anode.

[0128] The first electrode can be formed by sputtering or depositing a material used as the first electrode on a substrate. When the first electrode is an anode, an oxide transparent conductive material such as indium tin oxide (ITO), indium zinc oxide (IZO), tin dioxide (SnO2), zinc oxide (ZnO), and any combination thereof can be used. When the first electrode is a cathode, a metal or an alloy such as magnesium (Mg), silver (Ag), aluminum (Al), aluminum-lithium (Al-Li), calcium (Ca), ytterbium (Yb), magnesium-indium (Mg-In), magnesium-silver (Mg-Ag), and any combination thereof can be used.

[0129] The organic material layer can be formed on the electrode by vacuum thermal evaporation, spin coating, printing, or the like. The compound used as the organic material layer can be an organic small molecule, an organic macromolecule, and a polymer, and a combination thereof.

[0130] The hole transport zone is located between the anode and the light emitting layer. The hole transport zone can be a single layer structure of a hole transport layer (HTL), including a single layer hole transport layer containing only one kind of compound and a single layer hole transport layer containing multiple kinds of compounds. The hole transport zone can also be a multi-layer structure including at least one of a hole injection layer (HIL), a hole transport layer (HTL), and an electron blocking layer (EBL); wherein the HIL is located between the anode and the HTL, and the EBL is located between the HTL and the light emitting layer.

[0131] The material of the hole transport zone can be selected from, but not limited to, phthalocyanine derivatives such as CuPc, conductive polymers or conductive dopant-containing polymers such as polyphenylene vinylene, polyaniline / dodecylbenzenesulfonic acid (Pani / DBSA), poly(3,4-ethylenedioxythiophene) / poly(4-styrenesulfonate) (PEDOT / PSS), polyaniline / camphor sulfonic acid (Pani / CSA), polyaniline / poly(4-styrenesulfonate) (Pani / PSS), aromatic amine derivatives such as the compounds shown in HT-1 to HT-51 below; or any combination thereof.

[0132]

[0133]

[0134]

[0135]

[0136] The hole injection layer is located between the anode and the hole transport layer. The hole injection layer can be a single compound material or a combination of multiple compounds. For example, the hole injection layer can employ one or more of the compounds of HT-1 to HT-51 described above, or one or more of the compounds of HI-1 to HI-3 described below; or one or more of the compounds of HT-1 to HT-51 can be used to dope one or more of the compounds of HI-1 to HI-3 described below.

[0137]

[0138] The light emitting layer includes light emitting dyes (i.e. dopants) that can emit different wavelengths of light spectrum, and can also include host materials (Host). The light emitting layer can be a single color light emitting layer that emits a single color such as red, green, blue, etc. Multiple single color light emitting layers of different colors can be arranged in a planar pattern according to a pixel pattern, or can be stacked together to form a color light emitting layer. When the light emitting layers of different colors are stacked together, they can be separated from each other or connected to each other. The light emitting layer can also be a single color light emitting layer that can emit different colors such as red, green, blue, etc. simultaneously.

[0139] Depending on the technology, the light-emitting layer material can employ fluorescent electroluminescent materials, phosphorescent electroluminescent materials, thermally activated delayed fluorescence light-emitting materials, and the like. In an OLED device, a single light-emitting technology can be employed, or a combination of different light-emitting technologies can be employed. These different light-emitting materials, classified by technology, can emit the same color of light, or different colors of light.

[0140] In an aspect of the present application, the light-emitting layer employs fluorescent electroluminescent technology. The fluorescent host material of the light-emitting layer can be selected from, but not limited to, a combination of one or more of the following BFH-1 to BFH-17.

[0141]

[0142]

[0143] In an aspect of the present application, the light-emitting layer employs phosphorescent electroluminescent technology. The host material of the light-emitting layer can be selected from, but not limited to, a combination of one or more of PH-1 to PH-87.

[0144]

[0145]

[0146]

[0147]

[0148] In an aspect of the present application, the light-emitting layer employs phosphorescent electroluminescent technology. The phosphorescent dopant of the light-emitting layer can be selected from, but not limited to, a combination of one or more of the following BPD-1 to BPD-16.

[0149]

[0150] The fluorescent dopant of the light-emitting layer can be selected from, but not limited to, a combination of one or more of the following TDE1 to TDE49:

[0151]

[0152]

[0153]

[0154]

[0155] In an aspect of the present application, the blocking layer around the light-emitting layer can be selected from, but not limited to, a combination of one or more of PH-1 to PH-87.

[0156] In one aspect of the present application, an electron blocking layer (EBL) is located between the hole transport layer and the light-emitting layer. The electron blocking layer can employ, but is not limited to, one or more compounds of HT-1 to HT-51 described above, or one or more compounds of PH-47 to PH-86 described above; or a mixture of one or more compounds of HT-1 to HT-51 and one or more compounds of PH-47 to PH-86.

[0157] The OLED organic material layer can further include an electron transport zone between the light-emitting layer and the cathode. The electron transport zone can be a single-layer structure of an electron transport layer (ETL), including a single-layer electron transport layer containing only one compound and a single-layer electron transport layer containing multiple compounds. The electron transport zone can also be a multi-layer structure including at least one of an electron injection layer (EIL), an electron transport layer (ETL), and a hole blocking layer (HBL).

[0158] In one aspect of the present application, the electron transport layer material can be selected from, but is not limited to, a combination of one or more of ET-1 to ET-73 listed below.

[0159]

[0160]

[0161]

[0162]

[0163] In one aspect of the present application, a hole blocking layer (HBL) is located between the electron transport layer and the light-emitting layer. The hole blocking layer can employ, but is not limited to, one or more compounds of ET-1 to ET-73 described above, or one or more compounds of PH-1 to PH-46, PH-87; or a mixture of one or more compounds of ET-1 to ET-73 and one or more compounds of PH-1 to PH-46, PH-87.

[0164] The organic electroluminescent device can further include an electron injection layer between the electron transport layer and the cathode, and the electron injection layer material includes, but is not limited to, a combination of one or more of LiQ, LiF, NaCl, CsF, Li2O, Cs2CO3, BaO, Na, Li, Ca, Mg, or Yb.

[0165] In a fourth aspect, the present application provides an electronic device having a display screen or panel, characterized in that the display screen or panel employs the organic electroluminescent device described above.

[0166] Compared with the prior art, the present application has the following beneficial effects:

[0167] The boron-nitrogen compound has a structure as shown in Formula I, and has excellent photoelectric properties due to the special design of the molecular structure (Formula a and Formula 2). The boron-nitrogen compound is applied to an organic electroluminescent device, and is especially suitable for being used as a light-emitting layer doping material, so that the current efficiency of the device can be effectively improved, the service life is prolonged, and the comprehensive performance of the organic electroluminescent device is comprehensively improved. DETAILED DESCRIPTION

[0168] The technical solutions of the present application are further described below through specific embodiments. Those skilled in the art should understand that the embodiments are only used to help understand the present application, and should not be regarded as specific limitations on the present application.

[0169] The preparation method of the compound of Formula I includes but is not limited to the following synthesis method. Those skilled in the art can also make routine adjustments to the preparation method according to actual needs, and the compound having the structure shown in Formula I synthesized by using other methods also belongs to the protection scope of the present application.

[0170] The following synthesis examples of the present application exemplarily provide specific synthesis methods of representative compounds. The solvents and reagents used in the synthesis examples can be purchased or customized from the chemical product market. The mass spectrometry (MS, m / z) characterization data of the intermediates and target products in the following specific embodiments of the present application are obtained by liquid chromatography-mass spectrometry (instrument model 6530 LC / Q-TOF, Agilent, ion source: ESI+APCI), and the specific is M+1. For the same molecular weight, the structure of the compound with different substitution sites can be distinguished and confirmed by referring to the HPLC peak time and using different raw materials.

[0171] Synthesis Example 1

[0172] The present synthesis example provides a compound M1, and the synthesis method thereof is as follows:

[0173]

[0174] (1) Synthesis of intermediate M1-1

[0175] 5-chloro-1,3-dibromobenzene (20 g), bis(4-tert-butylphenyl)amine (41.64 g), Pd132 (2.62 g), and sodium tert-butoxide (28.44 g) were added into a 1000 mL flask, 400 mL of toluene was added, and the mixture was heated to reflux under nitrogen protection for 4 hours. The solvent was rotary dried, and silica gel was added to the sample column for column chromatography to obtain the intermediate M1-1 (white solid, 31.7 g).

[0176] The mass spectrum data of intermediate M1-1 was characterized, and the mass spectrum data was 671.38 (theoretical value 670.41) was measured;

[0177] (2) Synthesis of intermediate M1-2

[0178] Intermediate M1-1 (10 g), boron tribromide (18.66 g), 1,2,4-trichlorobenzene (100 mL) were added to a 500 mL pressure-resistant reaction bottle, heated to 180°C under nitrogen protection, reacted for 24 hours, extracted with dichloromethane and water, the organic phases were combined, the solvent was rotary evaporated, and column chromatography on silica gel was performed to obtain intermediate M1-2 (yellow solid, 2.03 g);

[0179] The mass spectrum data of intermediate M1-2 was characterized, and the mass spectrum data was 679.33 (theoretical value 678.39) was measured;

[0180] (2) Synthesis of compound M1

[0181] Intermediate M1-2 (2 g), [2,3] benzocarbazole (0.64 g), Pd132 (0.1 g), sodium tert-butoxide (0.57 g) were added to a 250 mL flask, 400 mL of toluene was added, heated to reflux under nitrogen protection, reacted for 2 hours, the solvent was rotary evaporated, and column chromatography on silica gel was performed to obtain compound M1 (yellow solid, 0.78 g);

[0182] The mass spectrum data of compound M1 was characterized, and the mass spectrum data was 860.46 (theoretical value 859.50) was measured.

[0183] Synthesis Example 2

[0184] This synthesis example provides compound M21, and the synthesis method is as follows:

[0185]

[0186] (1) Synthesis of intermediate M21-1

[0187] 3-chloro-5-fluoro-bromobenzene (10 g), 3,6-di-tert-butylcarbazole (13.34 g), cesium carbonate (31.11 g) were added to a 1000 mL flask, 200 mL of DMF was added, heated to 100°C under nitrogen protection, reacted for 12 hours, the solvent was rotary evaporated, and column chromatography on silica gel was performed to obtain intermediate M21-1 (white solid, 21.31 g);

[0188] The mass spectrum data of intermediate M21-1 was characterized, and the mass spectrum data was 468.08 (theoretical value 467.10) was measured;

[0189] (2) Synthesis of intermediate M21-2

[0190] Into a 500 mL flask was placed intermediate M21-1 (20 g), 4-tert-butylaniline (6.37 g), Pd(dppf)Cl2(1.74 g), sodium tert-butoxide (8.20 g), toluene (200 mL), heated to 110 °C under nitrogen protection for 12 hours, the solvent was rotary evaporated, and column chromatography on silica gel was performed to give intermediate M21-2 (white solid, 17.31 g);

[0191] The mass spectrometry data of intermediate M21-2 was characterized, and the mass spectrometry data was measured as 537.31 (theoretical value 536.30);

[0192] (3) Synthesis of intermediate M21-3

[0193] Into a 500 mL flask was placed intermediate M21-2 (10 g), 2-bromo-4-tert-butylbenzothiophene (5.01 g), Pd132 (0.66 g), sodium tert-butoxide (3.58 g), 100 mL toluene was added, heated to 110 °C under nitrogen protection for 4 hours, the solvent was rotary evaporated, and column chromatography on silica gel was performed to give intermediate M21-3 (white solid, 10.33 g);

[0194] The mass spectrometry data of intermediate M21-3 was characterized, and the mass spectrometry data was measured as 725.41 (theoretical value 724.36).

[0195] (4) Synthesis of intermediate M21-4

[0196] Intermediate M21-4 was prepared according to the preparation method of intermediate M1-2, except that intermediate M1-1 was replaced by an equivalent amount of intermediate M21-3, and intermediate M21-4 was prepared;

[0197] The mass spectrometry data of intermediate M21-4 was characterized, and the mass spectrometry data was measured as 733.36 (theoretical value 732.35);

[0198] (4) Synthesis of compound M21

[0199] Compound M21 was prepared according to the preparation method of compound M1, except that intermediate M1-2 was replaced by an equivalent amount of intermediate M21-4, and compound M21 was prepared;

[0200] The mass spectrometry data of compound M21 was characterized, and the mass spectrometry data was measured as 914.50 (theoretical value 913.46).

[0201] Synthesis Example 3

[0202] This synthesis example provides compound M57, and the synthesis method thereof is as follows:

[0203]

[0204] Intermediate M1-2 (2 g), naphthobenzofuran-4-boronic acid (0.77 g), Pd132 (0.1 g), potassium carbonate (0.8 g) were added into a 100 mL flask, then 1,4-dioxane (20 mL), 4 ml water (4 mL) were added into the flask, heated to reflux under nitrogen protection, reacted overnight, the solvent was rotary evaporated, and the silica gel was column chromatographed to obtain compound M57 (yellow solid, 0.92 g);

[0205] The mass spectrometry data of compound M57 was characterized, and the mass spectrometry data was 861.45 (theoretical value 860.49).

[0206] The present application exemplarily gives the specific synthesis method of representative intermediates and part of compounds. For other compounds without specific synthesis method, they can also be prepared by similar methods, and the starting materials are replaced to obtain them, which will not be repeated here, or the skilled person in the art can also prepare them by other ways in the prior art.

[0207] Device Example 1

[0208] An organic electroluminescent device comprises an anode (ITO), a hole injection layer, a hole transport layer, an electron blocking layer, a light emitting layer, an electron transport layer, an electron injection layer and a cathode (Al) arranged in sequence; the specific preparation method is as follows:

[0209] (1) The glass plate coated with ITO transparent conductive layer was ultrasonically treated in a commercial cleaning agent, washed in deionized water, ultrasonically degreased in a mixed solvent of acetone: ethanol, baked in a clean environment until the water was completely removed, washed with ultraviolet light and ozone, and the surface was bombarded with low-energy cation beams;

[0210] (2) The glass plate with ITO anode was placed in a vacuum chamber, vacuumized to <1×10 -5 Pa, a mixture of compounds HT-4: HI-3 (97 / 3, w / w) was vacuum thermal evaporated on the anode layer as a hole injection layer, the evaporation rate was 0.1 nm / s, and the evaporation film thickness was 10 nm;

[0211] (3) Compound HT-4 was vacuum evaporated on the hole injection layer as a hole transport layer, the evaporation rate was 0.1 nm / s, and the film thickness was 60 nm;

[0212] (4) Compound HT-14 was vacuum evaporated on the hole transport layer as an electron blocking layer, the evaporation rate was 0.1 nm / s, and the film thickness was 5 nm;

[0213] (5) Vacuum deposition of a light-emitting layer comprising a host material (BFH-4) and a dopant material (compound M1) on the electron blocking layer, the mass ratio (w / w) of the host material to the dopant material being 100:3, the deposition rate being 0.1 nm / s, and the total film thickness being 20 nm;

[0214] (6) Vacuum deposition of compound ET-23 as a hole blocking layer on the light-emitting layer, the deposition rate being 0.1 nm / s, and the film thickness being 5 nm;

[0215] (7) Vacuum deposition of a mixture of compounds ET-69:ET-57 (50 / 50, w / w) as an electron transport layer on the hole blocking layer, the deposition rate being 0.1 nm / s, and the total film thickness being 25 nm;

[0216] (8) Vacuum deposition of compound LiF as an electron injection layer on the electron transport layer, the deposition rate being 0.1 nm / s, and the thickness being 1 nm;

[0217] (9) Vacuum deposition of aluminum as a cathode on the electron injection layer, the thickness being 150 nm, and the deposition rate being 1 nm / s, to obtain the organic electroluminescent device.

[0218] Device Examples 2-15, Device Comparative Examples 1-9

[0219] An organic electroluminescent device, which differs from Example 1 only in that the dopant material of the light-emitting layer is replaced by the material in Table 1.

[0220] Device Example 16

[0221] An organic electroluminescent device, which differs from Example 1 only in that the electron blocking layer material is replaced by PH-86, the light-emitting layer is replaced by a host material, a phosphorescent sensitizer, and a dopant material in a ratio of 89:10:1 (w / w / w), the host material is a mixed host of PH-86:PH-87 (60 / 40, w / w), the phosphorescent sensitizer is BPD-1, the dopant material is the organic compound M1 provided by the present application, and the hole blocking layer is replaced by PH-87.

[0222] Device Examples 17-30, Device Comparative Examples 10-18

[0223] An organic electroluminescent device, which differs from Example 16 only in that the dopant material of the light-emitting layer is replaced by the material in Table 2.

[0224] The structures of the dopant materials in the above device comparative examples are as follows:

[0225]

[0226] The following performance measurements were made on the organic electroluminescent device described above:

[0227] (1) The external quantum efficiency (EQE, %) of the device was measured using the integrating sphere method;

[0228] (2) The lifetime of the organic electroluminescent device prepared in device examples 1-30 and device comparative examples 1-18 was measured at the same brightness using a digital source meter and a PR650. Specifically, the LT97 lifetime test was as follows:

[0229] The initial brightness value of the device was measured using a luminance meter at 40 mA / cm 2 The time for the brightness of the device to decrease to 97% of the initial brightness was measured at a constant current, in hours; the LT97 lifetime test value of device comparative examples 1 and 10 was taken as 1.0, and the ratio of the LT97 lifetime test value of other devices to the LT97 lifetime test value of device comparative examples 1 and 10 was calculated;

[0230] The performance data of the organic electroluminescent device prepared in each of the device examples and comparative examples described above are shown in Tables 1 and 2 below.

[0231] Table 1

[0232]

[0233]

[0234] Table 2

[0235]

[0236]

[0237]

[0238] As can be seen from the data in Tables 1 and 2, the compounds provided by the present application, when used in organic electroluminescent devices, are suitable as doping materials for light-emitting layers, and can effectively improve the current efficiency and prolong the service life of the device.

[0239] Compared with compound C1, the compounds provided by the present application exhibit higher efficiency and longer lifetime, which is likely due to the nitrogen atom in the benzocarbazole structure of compound C1 quenching the luminescence of the compound, and the lone pair of electrons on the N atom being prone to reacting with other molecules, thereby leading to poor lifetime.

[0240] Compared with compound C2, the compounds provided by the present application exhibit higher efficiency, and the light color is more blue, which is likely due to the fused phenyl group on the carbazole group of compound C2 leading to increased conjugation of the compound, thereby leading to severe red shift of luminescence, deviating from blue light emission, and also leading to increased intramolecular vibration, reducing the luminescent efficiency.

[0241] The compound of the present application shows longer lifetime compared with compound C3 and compound C4, which may be due to the higher triplet energy level of the structure of benzocarbazole group and naphthobenzofuran in compound C3 and compound C4, thus leading to higher energy release in the process of compound quenching, and thus poorer device stability.

[0242] The compound of the present application shows higher efficiency and longer lifetime compared with compound C5, which may be due to the connected position of benzocarbazole group in compound C5, leading to easier occurrence of exciton quenching, thus affecting the efficiency and lifetime of the device.

[0243] The compound of the present application shows higher efficiency and more blue light color compared with compound C6, which may be due to the special fused structure of compound C6, leading to too planar molecule, thus serious red shift of light color, and in addition, leading to easier occurrence of exciton quenching, thus lower efficiency.

[0244] The compound of the present application shows higher efficiency and longer lifetime compared with compound C7, which may be due to the dibenzocarbazole structure in compound C7, leading to more serious exciton quenching, thus affecting the efficiency and lifetime of the device.

[0245] The compound of the present application shows higher efficiency and longer lifetime compared with compound C8, which may be due to the unstable C-O bond in compound C8, leading to easy cleavage, thus affecting the efficiency and lifetime of the device.

[0246] The compound of the present application shows longer lifetime and more blue light color compared with compound C9, which may be due to the connection of benzocarbazole and mother nucleus in compound C9, leading to increased conjugation of the compound, thus red shift of light color, and in addition, the chemical bond leads to larger molecular structure tension, thus easier occurrence of chemical bond cleavage of the compound, thus leading to decreased stability.

[0247] The applicant declares that the present application is illustrated by the above examples for a compound of the present application and its application, an organic electroluminescent device comprising the same, but the present application is not limited to the above examples, i.e. it does not mean that the present application must rely on the above examples to be implemented. It should be understood by those skilled in the art that any improvement of the present application, equivalent replacement of each raw material of the product of the present application, addition of auxiliary ingredients, selection of specific mode, etc. fall within the protection scope and disclosure scope of the present application.

Claims

1. A boron-nitrogen compound, characterized in that, The boron-nitrogen compound has the structure shown in Formula I: Ar1 and Ar2 are each independently selected from one of substituted or unsubstituted C6-C60 aryl groups and substituted or unsubstituted C3-C60 heteroaryl groups; Ring A, ring D, and ring C are each independently selected from any one of the following: substituted or unsubstituted C6-C20 aromatic rings, substituted or unsubstituted oxygen-containing atoms, sulfur atoms, or nitrogen atoms, and C7-C30 heteroaromatic rings. Among them, at least one of ring A and ring D is selected from the structure shown in formula a, and the dashed line represents the fusion site of the structure shown in formula a. Wherein, U1, U2, U3, and U4 are each independently selected from N or CR′, and R′ are each independently selected from any one of hydrogen, halogen, cyano, substituted or unsubstituted C1-C20 straight-chain or branched alkyl, substituted or unsubstituted C3-C20 cycloalkyl, substituted or unsubstituted C6-C30 aryl, and substituted or unsubstituted C3-C30 heteroaryl; At least one group with the structure shown in Formula 2 is present on ring A, ring D, and ring C. The group shown in Formula 2 is not fused with ring A, ring D, and ring C, and is not connected to Ar1 or Ar2. The dashed lines represent the connection sites of the group. Wherein, X1 is selected from any one of NR2, O, S or CR3R4; when X1 is selected from NR2 or CR3R4, the group shown in Formula 2 is connected to ring A, ring D, or ring C; when X1 is selected from O or S, the group shown in Formula 2 is connected to ring C. Z1, Z2, Z3, and Z4 are each independently selected from N or CR″; m represents any integer from 0 to 6; R1 is independently selected from any one of halogen, cyano, substituted or unsubstituted C1-C20 straight-chain or branched alkyl, substituted or unsubstituted C3-C20 cycloalkyl, substituted or unsubstituted C1-C20 alkoxy, substituted or unsubstituted C1-C20 alkylsilyl, substituted or unsubstituted C1-C20 alkylthio, substituted or unsubstituted C6-C30 arylamino, substituted or unsubstituted C3-C30 heteroarylamino, substituted or unsubstituted C6-C30 aryloxy, substituted or unsubstituted C3-C30 heteroaryloxy, substituted or unsubstituted C6-C30 arylthio, substituted or unsubstituted C6-C30 arylsilyl, substituted or unsubstituted C6-C30 aryl, and substituted or unsubstituted C3-C30 heteroaryl. When m is greater than or equal to 2, R1 are either the same or different from each other, and any two adjacent R1 are not connected or are connected by a single bond; R2 is selected from any one of single bond, hydrogen, substituted or unsubstituted C6-C30 aryl, substituted or unsubstituted C3-C30 heteroaryl; R3, R4, and R″ are each independently selected from any one of hydrogen, halogen, cyano, substituted or unsubstituted C1-C20 straight-chain or branched alkyl, substituted or unsubstituted C3-C20 cycloalkyl, substituted or unsubstituted C1-C20 alkoxy, substituted or unsubstituted C1-C20 alkylsilyl, substituted or unsubstituted C1-C20 alkylthio, substituted or unsubstituted C6-C30 arylamino, substituted or unsubstituted C3-C30 heteroarylamino, substituted or unsubstituted C6-C30 aryloxy, substituted or unsubstituted C3-C30 heteroaryloxy, substituted or unsubstituted C6-C30 arylthio, substituted or unsubstituted C6-C30 arylsilyl, substituted or unsubstituted C6-C30 aryl, and substituted or unsubstituted C3-C30 heteroaryl. The substituents in Ar1, Ar2, ring A, ring D, ring C, R′, R″, R1, R2, R3, and R4 are independently selected from halogens, cyano groups, unsubstituted groups, or R... a Substituted C1-C30 straight-chain or branched alkyl groups, unsubstituted or R a Substituted C1-C30 alkoxy, unsubstituted or R a Substituted C1-C30 alkylthio groups, unsubstituted or R a Substituted C3-C30 cycloalkyl, unsubstituted or R a Substituted C6-C30 aryl, unsubstituted or R a Substituted C3-C30 heteroaryl, unsubstituted or R a Substituted C6-C30 aryloxy groups, unsubstituted or R a Substituted C6-C30 arylthio, unsubstituted or R a Substituted C1-C30 alkylsilyl, unsubstituted or R a Substituted C6-C30 arylsilyl, unsubstituted or R a Any one of the substituted C6-C30 arylamino groups; R a Each is independently selected from at least one of halogen, cyano, C6-C20 aryl, C3-C20 heteroaryl, unsubstituted or halogenated C1-C10 straight-chain or branched alkyl; Any two adjacent rings in rings A, D, C, Ar1, and Ar2 are either not connected or connected by a single bond.

2. The boron-nitrogen compound according to claim 1, characterized in that, The group shown in Formula 2 includes groups having the following Formula 2-1 or Formula 2-2, where the dashed lines represent the linkage sites of the groups: Among them, X 11 Selected from NR 21 O, S or CR 31 R 41 Any one of them, when X 11 Selected from NR 21 or CR 31 R 41 The group shown in Formula 2-2 is connected to ring A, ring D, and ring C; when X 11 Selected from O or S, the group shown in Formula 2-2 is connected to a ring C; R 21 Selected from any one of unsubstituted or C1-C10 straight-chain or branched alkyl-substituted C6-C12 aryl groups and unsubstituted or C1-C10 straight-chain or branched alkyl-substituted C3-C12 heteroaryl groups; R 11 -R 14 R 31 R 41 Each of the following is independently selected from hydrogen, halogen, cyano, C1-C10 straight-chain or branched alkyl, C1-C10 alkoxy, C1-C10 alkylthio, C1-C10 alkylsilyl, C3-C10 cycloalkyl, C6-C12 aryl, C3-C12 heteroaryl, C6-C12 aryloxy, C6-C12 arylthio, C6-C12 arylsilyl, C6-C12 arylamino, and C3-C12 heteroarylamino, or a combination of at least two of them; m 11 m 21 Represents any integer from 0 to 4; m 12 m 22 Represents any integer from 0 to 6; m 11 When R is greater than or equal to 2, 11 Whether they are the same or different, R 11 No connection or single-key connection between them; m 12 When R is greater than or equal to 2, 12 Whether they are the same or different, R 12 The connections between them are either not connected or form a loop; m 21 When R is greater than or equal to 2, 13 Whether they are the same or different, R 13 No connection or single-key connection between them; m 22 When R is greater than or equal to 2, 14 Whether they are the same or different, R 14 They are either not connected or form a loop; Preferably, the group represented by Formula 2 is selected from any one of the following groups: In this context, the dashed lines represent the bonding sites of functional groups.

3. The boron-nitrogen compound according to claim 1, characterized in that, The ring C is selected from the structure shown in formula b, and the dashed line represents the fusion site of the structure shown in formula b: Among them, Y1, Y2, and Y3 are independently selected from CR5 or N; R5 is independently selected from any one or a combination of at least two of the following groups: hydrogen, C1-C10 straight-chain or branched alkyl, C3-C10 cycloalkyl, C6-C20 aryl, C3-C15 heteroaryl, and the group shown in Formula 2. Preferably, at most one of Y1, Y2, and Y3 is N; Preferably, the ring C is selected from... Dashed lines represent The confluence sites; n1 represents any integer from 0 to 3; when n1 is greater than or equal to 2, R 51 They are the same or different; R 51 Each group is independently selected from H, C1-C10 straight-chain or branched alkyl groups, and any group shown in Formula 2.

4. The boron-nitrogen compound according to claim 1, characterized in that, Ring A and ring D are each independently selected from the structure shown in formula a or formula a-1, and at least one of ring A and ring D is selected from the structure shown in formula a. The dashed lines represent the fusion sites of the structure shown in formula a or formula a-1. Where X is selected from O or S; U1, U2, U3, and U4 have the same definition as equation a; U5, U6, U7, and U8 are each independently selected from N or CR′, where R′ has the same definition as equation a.

5. The boron-nitrogen compound according to claim 3, characterized in that, Rings A and D are each independently selected from... Dashed lines indicate The confluence sites; Wherein, n2 and n3 represent any integer from 0 to 4; when n2 is greater than or equal to 2, R6 are the same or different from each other; when n3 is greater than or equal to 2, R7 are the same or different from each other; R6 and R7 are independently selected from any one of hydrogen, halogen, cyano, C1-C6 straight-chain or branched alkyl, C3-C6 cycloalkyl, C6-C20 aryl or the group shown in Formula 2, and are further preferably any one of hydrogen, halogen, cyano, methyl, ethyl, propyl, isopropyl, tert-butyl, isopentyl, cyclohexyl, phenyl, naphthyl, or the group shown in Formula 2; Preferably, ring A is selected from n2 represents any integer from 0 to 4; when n2 is greater than or equal to 2, R6 are the same or different from each other; each of R6 is independently selected from any one of hydrogen, halogen, cyano, C1-6 straight-chain or branched alkyl, C3-C6 cycloalkyl, C6-C20 aryl, and the group shown in Formula 2, and is further preferably any one of hydrogen, halogen, cyano, methyl, ethyl, propyl, isopropyl, tert-butyl, isopentyl, cyclohexyl, phenyl, naphthyl, and the group shown in Formula 2; Preferably, ring D is selected from... More preferably selected from n2 and n3 represent any integer from 0 to 4; when n2 is greater than or equal to 2, R6 are the same or different from each other; when n3 is greater than or equal to 2, R7 are the same or different from each other; R6 and R7 are independently selected from any one of hydrogen, halogen, cyano, C1-C6 straight-chain or branched alkyl, C3-C6 cycloalkyl, C6-C20 aryl or the group shown in Formula 2, and are further preferably any one of hydrogen, halogen, cyano, methyl, ethyl, propyl, isopropyl, tert-butyl, isopentyl, cyclohexyl, phenyl, naphthyl, or the group shown in Formula 2.

6. The boron-nitrogen compound according to claim 1, characterized in that, Ar1 and Ar2 are each independently selected from any one of substituted or unsubstituted C6-20 aryl groups, substituted or unsubstituted C3-10 heteroaryl groups, and more preferably substituted or unsubstituted phenyl groups, substituted or unsubstituted biphenyl groups, substituted or unsubstituted phenylnaphthyl groups, or substituted or unsubstituted pyridyl groups. The substituent is selected from any one or a combination of at least two of halogen, cyano, C1-C6 straight-chain or branched alkyl, and C6-C12 aryl, and is more preferably any one of halogen, cyano, methyl, ethyl, propyl, isopropyl, isopentyl, tert-butyl, phenyl, or naphthyl.

7. The boron-nitrogen compound according to claim 1, characterized in that, The boron-nitrogen compounds have any one of the following structures:

8. The application of a boron-nitrogen compound as described in any one of claims 1-7, characterized in that, The boron-nitrogen compounds are used in organic electronic devices; Preferably, the boron-nitrogen compound is used in an organic electroluminescent device; Preferably, the boron-nitrogen compound is used as a light-emitting layer material in an organic electroluminescent device; Preferably, the boron-nitrogen compound is used as a luminescent dye in an organic electroluminescent device.

9. An organic electroluminescent device, characterized in that, The organic electroluminescent device includes a first electrode, a second electrode, and at least one organic layer disposed between the first electrode and the second electrode; the organic layer includes at least one boron-nitrogen compound as described in any one of claims 1-7.

10. The organic electroluminescent device according to claim 9, characterized in that, The organic layer includes a light-emitting layer, wherein the light-emitting layer includes at least one boron-nitrogen compound as described in any one of claims 1-7; Preferably, the light-emitting layer comprises a host material and a dopant material, wherein the dopant material comprises at least one boron-nitrogen compound as described in any one of claims 1-7.

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