CN115724871A - Boron-nitrogen compound and application thereof - Google Patents

Abstract

The invention provides a boron-nitrogen compound, an organic electroluminescent element and an organic electroluminescent material, wherein the structural formula of the boron-nitrogen compound is shown as a formula I. Compared with the prior art, the compound with the large pi conjugated group and the boron nitrogen atom as the parent nucleus is used as the light-emitting unit, on one hand, the resonance effect between the boron atom and the nitrogen atom can be utilized to realize the separation of HOMO and LUMO, so that the TADF effect is realized, and meanwhile, the boron atom and nitrogen atom hybrid unit and the large pi conjugated group have rigid skeleton structures, so that the relaxation degree of an excited state structure can be reduced, and the narrower half peak width is realized; on the other hand, by introducing different substituents on the rigid skeleton, the further adjustment of the delayed fluorescence lifetime and the half-peak width can be realized.

Description

Boron-nitrogen compound and application thereof

Technical Field

The invention belongs to the technical field of electroluminescence, and particularly relates to a boron-nitrogen compound, an organic electroluminescence element and an organic electroluminescence material.

Background

The traditional fluorescent material is limited by the statistical law of spin quantum, only singlet excitons accounting for 25% of the total excitons can be utilized in the electroluminescent process, the rest 75% of the triplet excitons are inactivated in a non-radiative transition mode, and the theoretical limit value of the quantum efficiency in the device is 25%. To increase the exciton utilization efficiency, the triplet excitons need to be converted to photons, achieving 100% internal quantum efficiency. The phosphorescent metal complex can convert triplet excitons into photons by utilizing the spin-orbit coupling effect of heavy metal atoms, but the approach faces the problem that the phosphorescent metal complex is expensive. Another approach to utilize triplet excitons is to develop light-emitting materials with Thermally Activated Delayed Fluorescence (TADF) properties, and to utilize the thermally activated reverse system cross-over (RISC) process to transfer the triplet excited state to the singlet excited state for fluorescence, thereby achieving full utilization of singlet and triplet excitons. Molecules with TADF properties generally have to satisfy two conditions: smaller singlet-triplet energy level difference (Δ E) _ST ) And higher fluorescence quantum efficiency (PLQY). On the one hand, smaller Δ E _ST The reverse intersystem crossing process of thermal activation is facilitated to occur, so that the utilization efficiency of triplet excitons is facilitated to be improved; on the other hand, the material needs to have higher PLQY, thereby promoting the attenuation of singlet excitons in the form of light and improving the efficiency of the device.

Major applications of the TADF molecules currently under developmentThe diameter is such that the introduction of the donor (D) and acceptor (A) groups results in an efficient spatial separation of the highest occupied orbital (HOMO) and the lowest unoccupied orbital (LUMO), thereby achieving a small Δ E _ST . However, the D-a structure exhibits a large Stokes shift due to the vibrational relaxation of its excited state, and has a broad emission spectrum, the full width at half maximum (FWHM) is generally 70nm to 100nm, and in practical applications, it is often necessary to use a filter or construct an optical microcavity to improve the color purity, but this may result in a decrease in the external quantum efficiency of the device or a complicated device structure.

Therefore, how to develop a fluorescent material having both TADF effect and narrow spectrum characteristic by proper chemical structure design to solve the defect of wide half-peak width faced by the above materials has become one of the problems to be solved by many prospective researchers in the field.

The present invention has been made in view of the above reasons.

Disclosure of Invention

In order to solve the problems in the prior art, the invention provides a boron-nitrogen compound, an organic electroluminescent element and an organic electroluminescent material.

In a first object of the present invention, there is provided a boron-nitrogen compound.

A second object of the present invention is to provide an organic electroluminescent element.

In a third aspect of the present invention, there is provided an organic electroluminescent material.

In order to achieve the purpose, the invention adopts the following technical scheme:

a boron-nitrogen compound, wherein the structural general formula of the boron-nitrogen compound is shown as formula I:

wherein: ring A and ring B are each independently selected from substituted or unsubstituted C ₆ ～C ₅₀ Aryl, substituted orUnsubstituted C ₆ ～C ₅₀ Arylamino, substituted or unsubstituted C ₂ ～C ₅₀ Heteroaryl groups; ring C is a five-membered heterocyclic ring or a six-membered carbocyclic ring;

x represents C or N;

two adjacent W's represent a group of the following formula (1) or formula (2);

G ¹ selected from the group consisting of CR ² R ³ 、SiR ² R ³ 、NR ⁴ O or S, Z, identical or different at each occurrence, represents CR ⁵ Or N, and ^ indicates two adjacent W in the formula I;

R ¹ ～R ⁵ are identical or different from each other and are each independently selected from hydrogen, deuterium, substituted or unsubstituted C ₁ ～C ₃₀ Alkyl, substituted or unsubstituted C ₆ ～C ₅₀ Aryl, substituted or unsubstituted C ₃ ～C ₃₀ Cycloalkyl, substituted or unsubstituted C ₂ ～C ₅₀ Heteroaryl, substituted or unsubstituted C ₁ ～C ₃₀ Alkoxy, substituted or unsubstituted C ₆ ～C ₅₀ Aryloxy, substituted or unsubstituted C ₁ ～C ₃₀ Alkylthio, substituted or unsubstituted C ₅ ～C ₅₀ Arylthio, substituted or unsubstituted C ₁ ～C ₃₀ Alkylamino radical, substituted or unsubstituted C ₅ ～C ₅₀ Arylamino, substituted or unsubstituted C ₁ ～C ₃₀ Alkylsilyl, substituted or unsubstituted C ₅ ～C ₅₀ Arylsilyl groups, nitro groups, cyano groups, or fluorine atoms;

Ar ¹ 、Ar ² each independently selected from substituted or unsubstituted C ₁ ～C ₃₀ Alkyl, substituted or unsubstituted C ₆ ～C ₅₀ Aryl, substituted or unsubstituted C ₃ ～C ₃₀ Cycloalkyl, substituted or unsubstituted C ₂ ～C ₅₀ Heteroaryl, substituted or unsubstituted C ₆ ～C ₅₀ Aryloxy, substituted or unsubstituted C ₅ ～C ₅₀ Arylthio, substituted or unsubstituted C ₅ ～C ₅₀ Arylamine, substituted or unsubstituted C ₅ ～C ₅₀ Arylsilyl groups.

Further, the boron-nitrogen compound is selected from any one of the following structures:

wherein G is ² 、G ³ Each independently selected from O, S, NR ⁶ 、SiR ⁷ R ⁸ 、BR ⁶ Or without G ² Or G ³ ；

R、R ⁶ 、R ⁷ 、R ⁸ At each occurrence, each is independently selected from hydrogen, deuterium, fluorine, substituted or unsubstituted C ₁ ～C ₃₀ Alkyl, substituted or unsubstituted C ₆ ～C ₅₀ Aryl, substituted or unsubstituted C ₃ ～C ₃₀ Cycloalkyl, substituted or unsubstituted C ₂ ～C ₅₀ Heteroaryl, substituted or unsubstituted C ₁ ～C ₃₀ Alkoxy, substituted or unsubstituted C ₆ ～C ₅₀ Aryloxy, substituted or unsubstituted C ₁ ～C ₃₀ Alkylthio, substituted or unsubstituted C ₅ ～C ₅₀ Arylthio, substituted or unsubstituted C ₁ ～C ₃₀ Alkylamino radical, substituted or unsubstituted C ₅ ～C ₅₀ Arylamino, substituted or unsubstituted C ₁ ～C ₃₀ Alkylsilyl, substituted or unsubstituted C ₅ ～C ₅₀ Arylsilyl groups, cyano groups;

R、R ⁵ each independently being one or more to saturated substitution, two or more R or R being adjacent ⁵ Optionally joined or fused to form a substituted or unsubstituted ring.

Further, said R ¹ Is hydrogen.

Further, said G ¹ Selected from O, S or NR ⁴ 。

Further, said G ² 、G ³ Each independently selected from O, S or NR ⁶ 。

Further, without said G ² 。

Further, without said G ³ 。

Aryl in the sense of the present invention contains from 6 to 50 carbon atoms and heteroaryl in the sense of the present invention contains from 2 to 50 carbon atoms and at least one heteroatom, with the proviso that the sum of carbon atoms and heteroatoms is at least 5; the heteroatom is preferably selected from N, O or S. Aryl or heteroaryl here means in particular radicals derived from: benzene, naphthalene, anthracene, benzanthracene, phenanthrene, pyrene,

Perylene, fluoranthene, tetracene, pentacene, benzopyrene, biphenyl, terphenyl, fluorene, spirobifluorene, dihydrophenanthrene, dihydropyrene, tetrahydropyrene, cis-or trans-indenofluorene, cis-or trans-indenocarbazole, cis-or trans-indolocarbazole, triindene, isotridendene, spirotriindene, spiroisotridendene, furan, benzofuran, isobenzofuran, dibenzofuran, thiophene, benzothiophene, isobenzothiophene, dibenzothiophene, pyrrole, indole, isoindole, carbazole, pyridine, quinoline, isoquinoline, acridine, phenanthridine, benzo [5,6,6]Quinoline, benzo [6,7 ]]Quinoline, benzo [7,8 ]]Quinoline, phenothiazine, phenoxazine, pyrazole, indazole, imidazole, benzimidazole, naphthoimidazole, phenanthroimidazole, pyridoimidazole, pyrazinoimidazole, quinoxaloimidazole, oxazole, benzoxazole, naphthooxazole, anthraoxazole, phenanthroixazole, isoxazoleOxazole, 1, 2-thiazole, 1, 3-thiazole, benzothiazole, pyridazine, hexaazatriphenylene, benzopyridazine, pyrimidine, benzopyrimidine, quinoxaline, 1, 5-diaza anthracene, 2, 7-diaza pyrene, 2, 3-diaza pyrene, 1, 6-diaza pyrene, 1, 8-diaza pyrene, 4, 5-diaza pyrene, 4,5,9,10-tetraazaperylene, pyrazine, phenazine, phenoxazine, phenothiazine, fluorrubine, naphthyridine, azacarbazole, benzocarbazine, carboline, phenanthroline, 1,2,3-triazole, 1,2,4-triazole, benzotriazole, 1,2,3-oxadiazole, 1,2,4-oxadiazole, 1,2,5-oxadiazole, 1,3,4-oxadiazole, 1,2,3-thiadiazole, 1,2,4-thiadiazole, 1,2,5-thiadiazole, 1,3,4-thiadiazole, 1,3,5-triazine, 1,2,4-triazine, 1,2,3-triazine, tetrazole, 1,2,4,5-tetrazine, 1,2,3,4-tetrazine, 1,2,3,5-tetrazine, purine, pteridine, indolizine, quinazoline, and benzothiadiazole, or a group derived from a combination of these systems.

The fused aryl group used in the present invention is a monovalent functional group obtained by combining two or more aromatic hydrocarbons having 6 to 50 carbon atoms in a ring and removing one hydrogen atom. In this case, two or more rings may be attached to each other simply or in a condensed form. As non-limiting examples thereof, may be mentioned phenanthryl, anthracyl, fluoranthenyl, pyrenyl, triphenylenyl, perylenyl, perylene,

And the like.

The arylamine group used in the present invention means an amine substituted with an aryl group having 6 to 50 carbon atoms, and non-limiting examples of the arylamine group include a diphenylamine group, an N-phenyl-1-naphthylamine group, an N- (1-naphthyl) -2-naphthylamine group and the like. The heteroarylamine group means an amine substituted with an aryl group having 6 to 50 carbon atoms and a heteroaryl group having 2 to 50 carbon atoms, and non-limiting examples of the heteroarylamine group include an N-phenylpyridine-3-amine group, an N- ([ 1,1 '-biphenyl ] -4-yl) dibenzo [ b, d ] furan-2-amine group, an N- ([ 1,1' -biphenyl ] -4-yl) -9, 9-dimethyl-9H-fluorene-2-amine group, and the like.

Containing 1 to 30 carbon atoms in the sense of the present invention and in which a single hydrogen atom or-CH ₂ The radicals aliphatic hydrocarbon or alkyl which may also be substituted by the abovementioned radicals, are preferably taken to mean the following radicals: methyl radicalEthyl, n-propyl, isopropyl, n-butyl, isobutyl, sec-butyl, tert-butyl, 2-methylbutyl, n-pentyl, sec-pentyl, neopentyl, cyclopentyl, n-hexyl, neohexyl, cyclohexyl, n-heptyl, cycloheptyl, n-octyl, cyclooctyl, 2-ethylhexyl, cyclohexenyl, heptenyl, cycloheptenyl, octenyl or cyclooctenyl.

Alkoxy is preferably alkoxy having from 1 to 30 carbon atoms, and is understood to mean methoxy, trifluoromethoxy, ethoxy, n-propoxy, isopropoxy, n-butoxy, isobutoxy, sec-butoxy, tert-butoxy, n-pentoxy, sec-pentoxy, 2-methylbutoxy, n-hexoxy, cyclohexyloxy, n-heptoxy, cycloheptoxy, n-octoxy, cyclooctoxy, 2-ethylhexoxy, pentafluoroethoxy and 2, 2-trifluoroethoxy.

Heteroalkyl is preferably alkyl having 1 to 30 carbon atoms, meaning that the individual hydrogen atoms or-CH ₂ The radicals which may be substituted by oxygen, sulfur, halogen atoms are understood to mean alkoxy, alkylthio, fluorinated alkoxy, fluorinated alkylthio, in particular methoxy, ethoxy, n-propoxy, isopropoxy, n-butoxy, isobutoxy, sec-butoxy, tert-butoxy, methylthio, ethylthio, n-propylthio, isopropylthio, n-butylthio, isobutylthio, sec-butylthio, tert-butylthio, trifluoromethylthio, trifluoromethoxy, pentafluoroethoxy, pentafluoroethylthio, 2-trifluoroethoxy, 2-trifluoroethylthio, vinyloxy, vinylthio, propenyloxy, propenylthio, butenylthio, butenyloxy, pentenyloxy, pentenylthio, cyclopentenyloxy, cyclopentenylthio, hexenyloxy, hexenylthio, cyclohexenyloxy, cyclohexenylthio, ethynyloxy, ethynylthio, propynyloxy, propynylthio, butynyloxy, butynylthio, pentynyloxy, pentynylthio, hexynyloxy, hexynylthio.

In general, cycloalkyl groups in the present invention can be cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, cyclobutenyl, cyclopentenyl, cyclohexenyl, cycloheptyl, cycloheptenyl, wherein one or more-CH groups ₂ The radicals may be replaced by the radicals mentioned above; furthermore, one orA plurality of hydrogen atoms may also be replaced by deuterium atoms, halogen atoms, or nitrile groups.

The alkylamino group used in the present invention means an amine substituted with an alkyl group having 1 to 30 carbon atoms or a cycloalkyl group having 3 to 30 carbon atoms, and non-limiting examples of the alkylamino group include a dimethylamino group, a diethylamino group, a dipropylamino group, a diisopropylamino group, and the like.

Further, R and R ² ～R ⁸ Each occurrence is independently selected from the group consisting of hydrogen, deuterium, methyl, ethyl, isopropyl, t-butyl, fluoro, nitrile, trimethylsilyl, substituted or unsubstituted phenyl, substituted or unsubstituted biphenyl, substituted or unsubstituted terphenyl, substituted or unsubstituted quaterphenyl, substituted or unsubstituted naphthyl, substituted or unsubstituted phenanthryl, substituted or unsubstituted triphenylene, substituted or unsubstituted anthracenyl, substituted or unsubstituted dibenzofuranyl, substituted or unsubstituted dibenzothiophenyl, substituted or unsubstituted fluorenyl, and substituted or unsubstituted carbazolyl.

Further, said Ar ¹ 、Ar ² Each independently selected from the group consisting of substituted or unsubstituted phenyl, substituted or unsubstituted biphenyl, substituted or unsubstituted terphenyl, substituted or unsubstituted quaterphenyl, substituted or unsubstituted naphthyl, substituted or unsubstituted phenanthryl, substituted or unsubstituted triphenylene, substituted or unsubstituted anthracenyl, substituted or unsubstituted dibenzofuranyl, substituted or unsubstituted dibenzothiophenyl, substituted or unsubstituted fluorenyl, and substituted or unsubstituted carbazolyl.

The alkenyl or alkynyl group in the present invention has 2 to 30 carbon atoms, and the alkenyl or alkynyl group in which individual hydrogen atoms may be substituted with the above-mentioned group R is preferably an ethenyl group, a propenyl group, a butenyl group, an isobutenyl group, a styryl group, a distyryl group, an ethynyl group, a propynyl group, a butynyl group, a phenylethynyl group; furthermore, one or more hydrogen atoms may also be replaced by deuterium atoms, halogen atoms or nitrile groups.

Aryloxy as used in the present invention means R' O ^- A monovalent functional group represented by the formula, R' isAn aryl group having 6 to 50 carbon atoms. As non-limiting examples of such aryloxy groups, there are phenoxy, naphthoxy, biphenyloxy and the like.

Arylthio as used in the present invention means R' S ^- The monovalent functional group represented by R' is an aryl group having 6 to 50 carbon atoms. As non-limiting examples of such arylthio groups, there are phenylthio, naphthylthio, biphenylthio and the like.

The alkylsilyl group used in the present invention means a silyl group substituted with an alkyl group having 1 to 30 carbon atoms, and the number of carbon atoms constituting the alkylsilyl group is at least 3, and as non-limiting examples of the alkylsilyl group, trimethylsilyl group, triethylsilyl group, and the like are given. The arylsilyl group means a silyl group substituted with an aryl group having 6 to 50 carbon atoms.

The arylphosphorus group used in the present invention means a diarylphosphorus group substituted with an aryl group having 6 to 50 carbon atoms, and as non-limiting examples of the arylphosphorus group, there are a diphenylphosphoryl group, a bis (4-trimethylsilylphenyl) phosphorus group and the like. The aryloxyphosphorus group is a group in which the phosphorus atom of the diarylphosphorus group is oxidized to the highest valence state.

The arylboron group used in the present invention means a diarylboron group substituted with an aryl group having 6 to 50 carbon atoms, and as non-limiting examples of the arylboron group, there are diphenylboron group, bis (2, 4, 6-trimethylphenyl) boron group and the like. The alkyl boron group means a dialkyl boron group substituted with an alkyl group having 1 to 30 carbon atoms, and non-limiting examples of the alkyl boron group include a di-t-butyl boron group, a diisobutyl boron group and the like.

"halo", "halogen atom", "halo" in the sense of the present invention are used interchangeably and refer to fluorine, chlorine, bromine or iodine.

As used herein, "a combination thereof" or "group" means that one or more members of the applicable list are combined to form a known or chemically stable arrangement that one of ordinary skill in the art would be able to envision from the applicable list. For example, alkyl and deuterium can be combined to form a partially or fully deuterated alkyl; halogen and alkyl groups may be combined to form haloalkyl substituents, such as trifluoromethyl and the like; and halogen, alkyl, and aryl groups may be combined to form haloaralkyl groups.

The term "substituted or unsubstituted" as used herein means a compound selected from the group consisting of hydrogen, deuterium, a halogen atom, a hydroxyl group, a nitrile group, a nitro group, an amino group, an amidino group, a hydrazine group, a hydrazone group, a carboxyl group or a carboxylate thereof, a sulfonic acid group or a sulfonate thereof, a phosphoric acid group or a phosphate thereof, and C ₁ -C ₃₀ Alkyl radical, C ₂ -C ₃₀ Alkenyl radical, C ₂ -C ₃₀ Alkynyl, C ₁ -C ₃₀ Alkoxy radical, C ₃ -C ₃₀ Cycloalkyl radical, C ₃ -C ₃₀ Cycloalkenyl radical, C ₆ -C ₅₀ Aryl radical, C ₆ -C ₅₀ Aryloxy group, C ₆ -C ₅₀ An arylthioether group and C ₂ -C ₅₀ The heterocyclic aryl group may be substituted or unsubstituted with 1 or more substituents, or may be substituted or unsubstituted with substituents formed by connecting 2 or more substituents among the above-exemplified substituents.

In one example, the term substitution includes combinations of two to four of the listed groups.

In another example, the term substitution includes a combination of two to three groups. In yet another example, the term substitution includes a combination of two groups. Preferred combinations of substituents are those containing up to fifty atoms not hydrogen or deuterium, or those containing up to forty atoms not hydrogen or deuterium, or those containing up to thirty atoms not hydrogen or deuterium. In many cases, a preferred combination of substituents will include up to twenty atoms that are not hydrogen or deuterium.

In the present invention, the "ring" refers to a substituted or unsubstituted hydrocarbon ring or a substituted or unsubstituted heterocyclic ring in which adjacent groups are bonded to each other to form a substituted or unsubstituted ring. The condensed ring is a condensed aliphatic ring, a condensed aromatic ring, a condensed aliphatic heterocyclic ring, a condensed aromatic heterocyclic ring, or a combination thereof.

Further, the compound of the formula I is selected from one of the compounds shown in the formulas B001 to B210:

wherein, G ¹ -O-, S-, or one of the following structures:

an organic electroluminescent material comprising the aforementioned boron-nitrogen compound.

An organic electroluminescent element comprising a first electrode, a second electrode and at least one organic layer interposed between said first electrode and said second electrode, said organic layer containing said boron-nitrogen compound.

Further, the organic layer comprises one or more of an electron injection layer, an electron transport layer, a hole injection layer, a hole transport layer, a hole blocking layer, an electron blocking layer, and a light emitting layer.

Further, the light-emitting layer includes a host compound and a dopant, and the host material includes a compound composed of the following chemical groups: triphenylene, carbazole, dibenzothiophene, dibenzofuran, dibenzoselenophene, azatriphenylene, azacarbazole, azadibenzothiophene, azadibenzofuran, azadibenzoselenophene, and triazine; said dopant comprising said boron-nitrogen compound;

wherein any substituent in the host material is independently selected from the group consisting of non-fused substituents consisting of: c _n H _2n+1 、OC _n H _2n+1 、OAr ³ 、N(C _n H _2n+1 ) ₂ 、N(Ar ³ )(Ar ⁴ )、CH＝CH-C _n H _2n+1 、C≡CC _n H _2n+1 、Ar ³ 、Ar ³ -Ar ⁴ 、C _n H _2n -Ar ³ Or no substituent, wherein n is an integer from 1 to 10; and wherein Ar ³ And Ar ⁴ Independently selected from the group consisting of: benzene, biphenyl, naphthalene, triphenylene, carbazole, and heteroaromatic analogs thereof.

Further, the host material is selected from one or more compounds shown in formulas A1-A90:

further, the mass ratio of the dopant to the host material is 1.

The organic electroluminescent material of the present invention may be composed of the boron-nitrogen compound of the present invention alone, or may contain other compounds at the same time.

The invention also includes an organic electroluminescent device comprising a cathode, an anode and at least one light-emitting layer. In addition to these layers, it may also comprise further layers, for example in each case one or more hole-injecting layers, hole-transporting layers, hole-blocking layers, electron-transporting layers, electron-injecting layers, exciton-blocking layers, electron-blocking layers and/or charge-generating layers. An intermediate layer having, for example, exciton blocking function can likewise be introduced between the two light-emitting layers. However, it should be noted that each of these layers need not be present. The organic electroluminescent device described herein may include one light emitting layer, or it may include a plurality of light emitting layers. That is, a plurality of light-emitting compounds capable of emitting light are used in the light-emitting layer. Particular preference is given to systems having three light-emitting layers, where the three layers can exhibit blue, green and red emission. If more than one light-emitting layer is present, at least one of these layers comprises the compounds of the invention according to the invention.

Further, the organic electroluminescent element according to the invention does not comprise a separate hole injection layer and/or hole transport layer and/or hole blocking layer and/or electron transport layer, i.e. the light-emitting layer is directly adjacent to the hole injection layer or anode and/or the light-emitting layer is directly adjacent to the electron transport layer or electron injection layer or cathode.

In the other layers of the organic electroluminescent element according to the invention, in particular in the hole-injecting and hole-transporting layer and in the electron-injecting and electron-transporting layer, all materials can be used in the manner conventionally used according to the prior art. The person skilled in the art will thus be able to use all materials known for organic electroluminescent elements in combination for the light-emitting layer according to the invention without inventive effort.

Preference is furthermore given to organic electroluminescent elements in which one or more layers can be applied by means of a sublimation process, in which the temperature in a vacuum sublimation apparatus is below 10 ^-5 Pa, preferably less than 10 ^-6 Pa is applied by vapor deposition. However, the initial pressure may also be even lower, e.g. below 10 ^-7 Pa。

Preference is likewise given to organic electroluminescent elements in which one or more layers can be applied by means of an organic vapor deposition method or by means of carrier gas sublimation, where 10 is ^-5 The material is applied under a pressure between Pa and 1 Pa. A particular example of this method is the organic vapour jet printing method, in which the material is applied directly through a nozzle and is therefore structured.

Preference is furthermore given to organic electroluminescent elements in which one or more layers are produced from solution, for example by spin coating, or by means of any desired printing method, for example screen printing, flexographic printing, offset printing, photoinitiated thermal imaging, thermal transfer, ink-jet printing or nozzle printing. Soluble compounds, for example, by appropriate substitution modification of the boron-nitrogen compounds to obtain soluble compounds. These methods are also particularly suitable for oligomers, dendrimers and polymers. Furthermore, hybrid methods are possible, in which, for example, one or more layers are applied from solution and one or more further layers are applied by vapor deposition.

These methods are generally known to those skilled in the art, and they can apply them to an organic electroluminescent element containing the boron-nitrogen compound of the present invention without inventive work.

The invention therefore also relates to a method for producing an organic electroluminescent element according to the invention, at least one layer being applicable by means of a sublimation method and/or by means of an organic vapour deposition method or by means of carrier gas sublimation and/or by spin coating or by means of a printing method from solution.

Furthermore, the present invention relates to a boron-nitrogen compound comprising at least one of the above-indicated present invention. The same preferred cases as those indicated above with respect to the organic electroluminescent element apply to the boron-nitrogen compound of the present invention. In particular, the boron-nitrogen compound may preferably contain other compounds in addition. Processing the boron-nitrogen compounds of the invention from the liquid phase, for example by spin coating or by printing methods, requires the preparation of the compounds according to the invention. These formulations may be, for example, solutions, dispersions or emulsions. For this purpose, it may be preferred to use a mixture of two or more solvents. Suitable and preferred solvents are, for example, toluene, anisole, o-xylene, m-or p-xylene, methyl benzoate, mesitylene, tetralin, o-dimethoxybenzene, tetrahydrofuran, methyltetrahydrofuran, tetrahydropyran, chlorobenzene, dioxane, phenoxytoluene, in particular 3-phenoxytoluene, (-) -fenchytone, 1,2,3, 5-tetramethylbenzene, 1,2,4, 5-tetramethylbenzene, 1-methylnaphthalene, 2-methylbenzothiazole, 2-phenoxyethanol, 2-pyrrolidone, 3-methylanisole, 4-methylanisole, 3, 4-dimethylanisole, 3, 5-dimethylanisole, acetophenone, alpha-terpineol, benzothiazole, butyl benzoate, cumene, cyclohexanol, cyclohexanone, cyclohexylbenzene, decalin, dodecylbenzene, ethyl benzoate, indane, methyl benzoate, 1-methylpyrrolidone, p-cymene, phenetole, 1, 4-diisopropylbenzene, dibenzyl ether, diethylene glycol butyl methyl ether, triethylene glycol dibutyl glycol methyl ether, triethyl glycol, tripropyl glycol, 1, 2-dimethyl benzyl ether, 1, 2-octylbenzene glycol, 1, 2-dimethyl-octylbenzene ether, 1, octylbenzene glycol, or mixtures of these solvents.

Compared with the prior art, the invention has the beneficial effects that:

according to the invention, a compound with a large pi conjugated group and a boron-nitrogen atom as parent nuclei is used as a light-emitting unit, on one hand, the resonance effect between the boron atom and the nitrogen atom is utilized to realize the separation of HOMO and LUMO, so that the TADF effect is realized, and meanwhile, the boron atom and nitrogen atom hybrid unit and the large pi conjugated group have a rigid skeleton structure, so that the relaxation degree of an excited state structure can be reduced, and the narrow half-peak width is realized; on the other hand, by introducing different substituents on the rigid skeleton, the further adjustment of the delayed fluorescence lifetime and the half-peak width can be realized, and the compound has narrower luminescence peak width and higher efficiency compared with the existing compound. Meanwhile, the boron-nitrogen compound has higher thermal stability, so that the service life of an organic electroluminescent element containing the compound is prolonged; the boron-nitrogen compound improves the solubility of the solution to solve the problems of productivity and cost of the conventional blue light emitting material, and can be used for preparing the light emitting layer not in the deposition step but in the solution step in the conventional process.

Drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below, it is obvious that the drawings in the following description are only some embodiments of the present invention, and for those skilled in the art, other drawings can be obtained according to the drawings without creative efforts.

Fig. 1 shows a schematic diagram of an organic light emitting device 100. The illustrations are not necessarily drawn to scale. The device 100 may include a substrate 101, an anode layer 102, a hole injection layer 103, a hole transport layer 104, an electron blocking layer 105, a light emitting layer 106, an electron transport layer 107, an electron injection layer 108, a cathode layer 109, and a capping layer (CPL) 110. The device 100 may be fabricated by sequentially depositing the described layers.

Fig. 2 shows a schematic diagram of an organic light emitting device 200 with two light emitting layers. The device comprises a substrate 201, an anode layer 202, a hole injection 203, a hole transport layer 204, a first light emitting layer 205, an electron transport layer 206, a charge generation layer 207, a hole injection layer 208, a hole transport layer 209, a second light emitting layer 210, an electron transport layer 211, an electron injection layer 212, and a cathode layer 213. The device 200 may be prepared by sequentially depositing the described layers. Since the most common OLED devices have one light emitting layer, while the device 200 has a first light emitting layer and a second light emitting layer, the light emitting peak shapes of the first light emitting layer and the second light emitting layer may be overlapping or cross-overlapping or non-overlapping. In the corresponding layers of device 200, materials similar to those described with respect to device 100 may be used. Fig. 2 provides one example of how some layers may be added from the structure of device 100.

Detailed Description

In order to make the objects, technical solutions and advantages of the present invention more apparent, the technical solutions of the present invention will be described in detail below. It should be apparent that the described embodiments are only some embodiments of the present invention, and not all embodiments. All other embodiments, which can be derived by a person skilled in the art from the examples given herein without any inventive step, are within the scope of the present invention.

"EQE" in the present invention refers to the external quantum efficiency of the device, i.e., the ratio of the number of photons emitted by the device to the number of electrons injected into the device.

The organic electroluminescent element described in the present invention includes at least one organic layer disposed between and electrically connected to an anode and a cathode. Fig. 1 shows a schematic diagram of an organic light emitting device 100. The illustrations are not necessarily drawn to scale. The device 100 may include a substrate 101, an anode 102, a hole injection layer 103, a hole transport layer 104, an electron blocking layer 105, a light emitting layer 106, an electron transport layer 107, an electron injection layer 108, a cathode 109, and a capping layer (CPL) 110. The device 100 may be fabricated by sequentially depositing the described layers.

Fig. 2 shows a schematic diagram of an organic light emitting device 200 containing two light emitting layers. The device comprises a substrate 201, an anode layer 202, a hole injection layer 203, a hole transport layer 204, a first light emitting layer 205, an electron transport layer 206, a charge generation layer 207, a hole injection layer 208, a hole transport layer 209, a second light emitting layer 210, an electron transport layer 211, an electron injection layer 212, and a cathode layer 213. The device 200 may be prepared by sequentially depositing the described layers. Since the most common OLED devices have one single color light emitting layer or three light emitting layers of three primary colors, while the device 200 has two light emitting layers of the same color. In corresponding layers of the device 200, materials similar to those described with respect to the device 100 may be used. Fig. 2 provides one example of how some layers may be added from the structure of device 100.

The simple layered structure illustrated in fig. 1 and 2 is provided as a non-limiting example, and it should be understood that embodiments of the present invention can be used in conjunction with a wide variety of other structures. The particular materials and structures described are exemplary in nature, and other materials and structures may be used. A functional OLED may be realized by combining the various layers described in different ways, or several layers may be omitted altogether, based on design, performance and cost factors. Other layers not specifically described may also be included. Materials other than those specifically described may be used. Although many of the examples provided herein describe the various layers as comprising a single material, it will be understood that combinations of materials may be used, such as mixtures of a host and a dopant, or more generally, mixtures. Also, the layer may have various sub-layers. The names given to the various layers herein are not intended to be strictly limiting. For example, in device 200, hole transport layer 204 transports holes and injects holes into light emitting layer 205, and may be described as a hole transport layer or an electron blocking layer. In one embodiment, an OLED may be described as having an organic layer disposed between a cathode and an anode. This organic layer may comprise a single layer or may further comprise multiple layers of different organic materials as described in fig. 1 and 2.

Structures and materials not specifically described, such as PLEDs comprising polymeric materials, may also be used. As another example, OLEDs having a single organic layer or multiple stacks may be used. The OLED structure may deviate from the simple layered structure illustrated in fig. 1 and 2. For example, the substrate may include an angled reflective surface to improve optical coupling.

Any of the layers of the various embodiments may be deposited by any suitable method, unless otherwise specified. For organic layers, preferred methods include thermal evaporation, organic vapor deposition methods or application of one or more layers by means of carrier gas sublimation, where 10 is ^-5 The material is applied at a pressure between mbar and 1 bar. A particular example of this method is the organic vapour jet printing method, in which the material is applied directly through a nozzle and is therefore structured. Other suitable deposition methods include creating one or more layers, for example by spin coating, or by any desired printing method, such as screen printing, flexographic printing, lithography, photo-induced thermal imaging, thermal transfer, ink jet printing, or nozzle printing. Soluble compounds, for example obtained by appropriate substitution. These methods are also particularly suitable for oligomers, dendrimers and polymers. Furthermore, hybrid methods are possible, in which one or more layers are applied, for example, from solution and one or more further layers are applied by vapor deposition.

Devices fabricated according to embodiments of the present invention may further optionally include a barrier layer. One purpose of the barrier layer is to protect the electrodes and organic layers from damage due to exposure to harmful substances in the environment, including moisture, vapor, and/or gas. The barrier layer may be deposited on, under or beside the substrate, electrode, or any other part of the device, including the edge. The barrier layer may comprise a single layer or multiple layers. The barrier layer may be formed by various known chemical vapor deposition techniques and may include compositions having a single phase as well as compositions having multiple phases. Any suitable material or combination of materials may be used for the barrier layer. The barrier layer may incorporate inorganic or organic compounds or both. Preferably, the barrier layer comprises a mixture of polymeric and non-polymeric materials. To be considered a mixture, the aforementioned polymeric and non-polymeric materials that make up the barrier layer should be deposited under the same conditions and/or at the same time. The weight ratio of polymeric material to non-polymeric material may be in the range of 95/5 to 5/95. In one example, the mixture of polymeric and non-polymeric materials consists essentially of polymeric and inorganic silicon.

In any of the above-mentioned compounds used in each layer of the above-mentioned OLED element, the hydrogen atoms may be partially or fully deuterated. Thus, any of the specifically listed substituents, such as (but not limited to) methyl, phenyl, pyridyl, and the like, can be in their non-deuterated, partially deuterated, and fully deuterated forms. Similarly, substituent classes (such as, but not limited to, alkyl, aryl, cycloalkyl, heteroaryl, etc.) can also be non-deuterated, partially deuterated, and fully deuterated forms thereof.

The materials and structures described herein can be applied to elements other than OLEDs. For example, other optoelectronic devices such as organic solar cells and organic photodetectors may use the materials and structures.

Further, organic devices such as organic transistors may use the materials and structures.

In the following examples of the present invention, a conventional production method is employed unless otherwise specified. The starting materials used are available from published commercial sources unless otherwise specified, and the percentages are by mass unless otherwise specified.

In order to more clearly illustrate the present invention, the following embodiments are provided to illustrate the technical solutions of the present invention:

in the embodiment of the invention, the performance detection conditions of the prepared electroluminescent device are as follows:

chromaticity coordinates: testing with a photosresearch PR-715 spectrum scanner;

current-voltage: testing using a digital source table Keithley 2420;

power efficiency: tested using NEWPORT 1931-C;

brightness: the test was carried out using a brightness meter Minolta Cs-1000A.

Example 1

A process for the preparation of compound B004, comprising the steps of:

the first step is as follows: preparation of intermediate Int-1

54.5mmol of 3-bromo-1-chloronaphthalene, 60.0mmol of 3, 6-di-tert-butyl-9- (1-adamantanecarbonyl) -1-carbazole boronic acid pinacol ester, 109.0mmol of potassium phosphate hydrate, 0.5mmol of Pd (PPh) ₃ ) ₄ Adding 120mL of toluene, 60mL of ethanol and 60mL of water into the catalyst, heating, refluxing and stirring the mixture to react for 10 hours under the protection of nitrogen, cooling the mixture to room temperature, adding 100mL of water, separating an organic phase, extracting a water phase by using ethyl acetate, combining the organic phase, drying the organic phase, filtering the organic phase, concentrating and drying the filtrate under reduced pressure, and separating and purifying the mixture by using a silica gel column to obtain yellow solid Int-1 with the yield of 77.5 percent.

The second step: preparation of intermediate Int-2

Under the protection of nitrogen, 50.0mmol of intermediate Int-1 is dissolved in 150mL of toluene, and 50.0mmol of 2, 7-di-tert-butylcarbazole, 75.0mmol of sodium tert-butoxide, 0.5mmol of cuprous iodide and 0.5mmol of Pd are added ₂ (dba) ₃ And 1.0mmol of 10% tri-tert-butylphosphine toluene solution, heating to 100 ℃, stirring for reaction for 12 hours, cooling to room temperature, adding 50mL of water, filtering, washing a filter cake with water and methanol, separating and purifying by using a silica gel column, and recrystallizing by using THF-ethanol to obtain yellow solid Int-2 with the yield of 81%.

The third step: preparation of intermediate Int-3

Under the protection of nitrogen, 40.0mmol of intermediate Int-2 is dissolved in 80mL of THF, 0.15mol of sodium hydroxide and 20mL of water are added, the mixture is heated up, refluxed and stirred for reaction for 12 hours, the reaction solution is cooled to room temperature, the THF is removed by concentration under reduced pressure, 100mL of water is added, the filtration is carried out, a filter cake is washed by water and methanol, the filter cake is separated and purified by a silica gel column and is recrystallized by THF-ethanol, and yellow solid Int-3 is obtained with the yield of 100%.

The fourth step: preparation of Compound B004

Under the protection of nitrogen, 10.0mmol of Int-3 prepared in the previous step and 120mL of dry chlorobenzene are mixed, 22.0mL of boron tribromide is slowly added dropwise, stirring reaction is carried out for 1 hour, 0.1mol of triethylamine is further added dropwise, the temperature is increased to 150 ℃, stirring reaction is carried out for 5 hours, cooling to room temperature, reduced pressure concentration and drying are carried out, and separation and purification are carried out by using a silica gel column, so that a compound B004, yellow solid, the yield is 35%, and MS (MALDI-TOF): m/z 690.4129[ M ] ⁺ ]And the elemental analysis result is as follows: theoretical value: c,86.94; h,7.44; b,1.56; n,4.06 (%); experimental values: c,86.80; h,7.57; b,1.51; n,4.12 (%).

The following compounds were prepared with reference to the analogous synthetic procedures described above

Example 2

A process for the preparation of compound B018, comprising the steps of:

the first step is as follows: preparation of intermediate Int-4

Under the protection of nitrogen, 25.0mmol of 3-bromo-indole, 125.0mmol of anhydrous potassium carbonate, 30.0mmol of 3, 6-di-tert-butylcarbazole, 0.5mmol of cuprous iodide and 1.5mmol of N, N' -dimethylethylenediamine are mixed, 120mL of xylene is added, the mixture is heated, refluxed, stirred and reacted for 15 hours, the temperature is reduced to room temperature, the mixture is filtered, blue filtrate is concentrated and dried under reduced pressure, and then the mixture is separated and purified by a silica gel column, so that yellow solid Int-4 is obtained, and the yield is 85.7%.

The second step is that: preparation of intermediate Int-5

Under the protection of nitrogen, 20.0mmol of intermediate Int-4 is dissolved in 100mL of pyridine, and 30.0mmol of 1-bromo-3, 6-di-tert-butyl-9- (1-adamantane formyl) carbazole, 35.0mmol of cesium carbonate and 0.2mmol of Pd are added ₂ (dba) ₃ And 0.4mmol of XantPhos, heating to 100 ℃, stirring for reaction for 12 hours, cooling to room temperature, adding 50mL of water, separating an organic phase, extracting a water phase with toluene, drying the organic phase, filtering, concentrating a filtrate under reduced pressure to dryness, separating and purifying with a silica gel column, and recrystallizing with toluene-ethanol to obtain Int-5 as a yellow solid with the yield of 75%.

The third step: preparation of intermediate Int-6

Referring to the synthesis procedure of the third step of example 1, the compound Int-6 was prepared in a yellow solid with a yield of 100% by replacing Int-5 with Int-2 only in the third step of example 1.

The fourth step: preparation of Compound B018

Under the protection of nitrogen, 10.0mmol of Int-6 prepared in the previous step and 120mL of dry chlorobenzene are mixed, 22.0mL of boron tribromide is slowly added dropwise, the mixture is stirred and reacted for 1 hour, then 0.1mol of diisopropylethylamine is added dropwise, the temperature is increased to 150 ℃, the mixture is stirred and reacted for 5 hours, the mixture is cooled to room temperature, and the mixture is concentrated and dried under reduced pressure and is separated and purified by a silica gel column to obtain a compound B018, yellow solid, the yield is 43%, and MS (MALDI-TOF): m/z 679.4086[ m ], [ 2 ] ⁺ ]And element analysis results: theoretical value: c,84.82; h,7.41; b,1.59; n,6.18 (%); experimental values: c,84.77; h,7.49; b,1.53; n,6.21 (%).

The following compounds were prepared with reference to the analogous synthetic procedures described above

In the above examples, ad represents 1-adamantyl.

Example 3

An organic electroluminescent device, as shown in fig. 1, has a substrate 101, an anode layer 102, a hole injection layer 103, a hole transport layer 104, an electron blocking layer 105, a light emitting layer 106, an electron transport layer 107, an electron injection layer 108, a cathode layer 109, and may include a light enhancement layer 110 and a CPL layer 111 on top of the cathode layer 109.

An organic light emitting device 200 having two light emitting layers, as shown in fig. 2, includes a substrate 201, an anode layer 202, a hole injection layer 203, a hole transport layer 204, a first light emitting layer 205, an electron transport layer 206, a charge generation layer 207, a hole injection layer 208, a hole transport layer 209, a second light emitting layer 210, an electron transport layer 211, an electron injection layer 212, and a cathode layer 213.

The method for manufacturing the organic electroluminescent device shown in fig. 1 of this embodiment includes the following steps:

(1) Sequentially carrying out ultrasonic treatment on the glass substrate coated with the ITO conductive layer in a cleaning agent for 30 minutes, washing in deionized water, carrying out ultrasonic treatment in an acetone/ethanol mixed solvent for 30 minutes, baking in a clean environment to be completely dried, irradiating for 10 minutes by using an ultraviolet light cleaning machine, bombarding the surface by using low-energy cation beams, placing the treated ITO glass substrate in a vacuum chamber, vacuumizing to less than 1 x 10 ^-5 Pa, depositing silver on the ITO film to a thickness of

The anode layer is obtained.

(2) Continuously depositing a compound DNTPD as a hole injection layer on the anode layer film to a thickness of

Continuously depositing HTM on the hole injection layer film to form a hole transport layer, wherein the deposition film has a thickness of

(3) Continuously evaporating a layer of compound HT202 on the hole transport layer as an electron blocking layer, and evaporating a filmIs thick as

(4) Continuously evaporating a layer of boron-nitrogen compound shown in formula I of the invention and A78 on the electron blocking layer to be used as an organic light-emitting layer, wherein A78 is a main material and the boron-nitrogen compound shown in formula I of the invention is a doping material, the doping concentration of the boron-nitrogen compound shown in formula I in A78 is 10%, and the thickness of the evaporation film is that

(5) And continuing to evaporate a layer of compounds LiQ and ET205 on the light-emitting layer to serve as an electron transport layer of the device, wherein the mass ratio of LiQ to ET205 is 1

(6) Continuously evaporating a layer of compound LiF on the electron transport layer as an electron injection layer of the element, wherein the thickness of the evaporated film is

(7) And depositing magnesium and silver on the electron injection layer by vapor deposition to form a cathode layer of the element, wherein the mass ratio of magnesium to silver is 2

(8) Depositing a compound HT038 as CPL layer on the cathode layer to a thickness of

The compound used in this example is of the formula:

comparative example 1

An organic electroluminescent device was produced by following the same procedure as in example 3, except that the compound BD028 was used instead of the boron-nitrogen compound of the present invention.

The structure of compound BD028 is:

test example 1

The organic electroluminescent devices prepared in example 3 and comparative example 1 were subjected to performance tests, specifically, voltage boosting at a rate of 0.1V per second, to determine that the luminance of the organic electroluminescent element reached 1000cd/m ² The current density is measured at the same time as the driving voltage; the ratio of the brightness to the current density is the current efficiency; the LT95% lifetime test is as follows: using a luminance meter at 1000cd/m ² The luminance degradation of the organic electroluminescent element was measured to 950cd/m while maintaining a constant current at luminance ² Time in hours. The data listed in table 3 are relative data compared to comparative example 1. The results are shown in Table 1.

TABLE 1 Performance test results

Wherein Me is methyl, ph is phenyl, tPh is p-tert-butylphenyl, phPhPh is biphenyl, nap is naphthyl, and FR is 9,9-spirofluorenyl.

The experimental data show that the compound realizes the separation of HOMO and LUMO through the boron-nitrogen resonance effect, so that the TADF effect is realized, and meanwhile, the hybrid unit of boron atoms and nitrogen atoms and the large-plane conjugated group have rigid skeleton structures, so that the relaxation degree of an excited state structure can be reduced, and the narrow half-peak width, the low driving voltage and the high luminous efficiency are realized. A blue organic electroluminescent element is obtained as a blue-light-doping material, and compared with an organic electroluminescent element using BD028 as a blue-light-doping material, the difference is that the boron atom of BD028 is bonded to two nitrogen atoms of two carbazoles, and HOMO and LUMO of molecules overlap, so that the full width at half maximum (FWHM) of the emission peak is wide, and the stability is poor, and thus the boron-nitrogen compound of the present invention is more excellent in element performance.

Industrial applicability of the compound of the present invention:

the organic electroluminescent device containing the compound of the present invention can be used in flat-panel light-emitting devices such as wall-mounted televisions, flat panel displays and illuminations, light sources such as back lights of copying machines, printers and liquid crystal displays and measuring instruments, display panels, sign lamps and the like.

The above description is only for the specific embodiments of the present invention, but the scope of the present invention is not limited thereto, and any person skilled in the art can easily conceive of the changes or substitutions within the technical scope of the present invention, and all the changes or substitutions should be covered within the scope of the present invention. Therefore, the protection scope of the present invention shall be subject to the protection scope of the claims.

Claims (10)

1. A boron-nitrogen compound is characterized in that the structural general formula of the boron-nitrogen compound is shown as formula I:

wherein: ring A and ring B are each independently selected from substituted or unsubstituted C ₆ ～C ₅₀ Aryl, substituted or unsubstituted C ₆ ～C ₅₀ Arylamino, substituted or unsubstituted C ₂ ～C ₅₀ Heteroaryl groups; ring C is a five-membered heterocyclic ring or a six-membered carbocyclic ring;

x represents C or N;

two adjacent W's represent a group of the following formula (1) or formula (2);

G ¹ selected from the group consisting of CR ² R ³ 、SiR ² R ³ 、NR ⁴ O or S, Z, identically or differently on each occurrence, represents CR ⁵ Or N, and ^ indicates two adjacent W in the formula I;

R ¹ ～R ⁵ are identical or different from each other and are each independently selected from hydrogen, deuterium, substituted or unsubstituted C ₁ ～C ₃₀ Alkyl, substituted or unsubstituted C ₆ ～C ₅₀ Aryl, substituted or unsubstituted C ₃ ～C ₃₀ Cycloalkyl, substituted or unsubstituted C ₂ ～C ₅₀ Heteroaryl, substituted or unsubstituted C ₁ ～C ₃₀ Alkoxy, substituted or unsubstituted C ₆ ～C ₅₀ Aryloxy, substituted or unsubstituted C ₁ ～C ₃₀ Alkylthio, substituted or unsubstituted C ₅ ～C ₅₀ Arylthio, substituted or unsubstituted C ₁ ～C ₃₀ Alkylamino radical, substituted or unsubstituted C ₅ ～C ₅₀ Arylamine, substituted or unsubstituted C ₁ ～C ₃₀ Alkylsilyl, substituted or unsubstituted C ₅ ～C ₅₀ Of arylsilyl, nitro, cyano, or fluorine atomsA group;

Ar ¹ 、Ar ² each independently selected from substituted or unsubstituted C ₁ ～C ₃₀ Alkyl, substituted or unsubstituted C ₆ ～C ₅₀ Aryl, substituted or unsubstituted C ₃ ～C ₃₀ Cycloalkyl, substituted or unsubstituted C ₂ ～C ₅₀ Heteroaryl, substituted or unsubstituted C ₆ ～C ₅₀ Aryloxy, substituted or unsubstituted C ₅ ～C ₅₀ Arylthio, substituted or unsubstituted C ₅ ～C ₅₀ Arylamine, substituted or unsubstituted C ₅ ～C ₅₀ Arylsilyl groups.

2. A boron-nitrogen compound according to claim 1, wherein the boron-nitrogen compound is selected from any one of the following structures:

wherein, G ² 、G ³ Each independently selected from O, S, NR ⁶ 、SiR ⁷ R ⁸ 、BR ⁶ Or without G ² Or G ³ ；

R、R ⁶ 、R ⁷ 、R ⁸ At each occurrence, each is independently selected from hydrogen, deuterium, fluorine, substituted or unsubstituted C ₁ ～C ₃₀ Alkyl, substituted or unsubstituted C ₆ ～C ₅₀ Aryl, substituted or unsubstituted C ₃ ～C ₃₀ Cycloalkyl, substituted or unsubstituted C ₂ ～C ₅₀ Heteroaryl, substituted or unsubstituted C ₁ ～C ₃₀ Alkoxy, substituted or unsubstituted C ₆ ～C ₅₀ Aryloxy, substituted or unsubstituted C ₁ ～C ₃₀ Alkylthio, substituted or unsubstituted C ₅ ～C ₅₀ Arylthio, substituted or unsubstituted C ₁ ～C ₃₀ Alkylamino radical, substituted or unsubstituted C ₅ ～C ₅₀ Arylamine, substituted or unsubstituted C ₁ ～C ₃₀ Alkylsilyl, substituted or unsubstituted C ₅ ～C ₅₀ Arylsilyl groups, cyano groups;

R、R ⁵ each independently being one or more, up to saturated substitution, two or more R or R being adjacent ⁵ Optionally joined or fused to form a substituted or unsubstituted ring.

3. A boron-nitrogen compound according to claim 2, wherein R is ¹ Is hydrogen;

G ¹ selected from O, S or NR ⁴ ；

G ² 、G ³ Each independently selected from O, S or NR ⁶ Or without G ² Or without G ³ ；

R、R ² ～R ⁸ Each occurrence is independently selected from the group consisting of hydrogen, deuterium, methyl, ethyl, isopropyl, tert-butyl, fluoro, nitrile, trimethylsilyl, substituted or unsubstituted phenyl, substituted or unsubstituted biphenyl, substituted or unsubstituted terphenyl, substituted or unsubstituted quaterphenyl, substituted or unsubstituted naphthyl, substituted or unsubstituted phenanthryl, substituted or unsubstituted triphenylene, substituted or unsubstituted anthracenyl, substituted or unsubstituted dibenzofuranyl, substituted or unsubstituted dibenzothiophenyl, substituted or unsubstituted fluorenyl, and substituted or unsubstituted carbazolyl;

Ar ¹ 、Ar ² each independently selected from the group consisting of substituted or unsubstituted phenyl, substituted or unsubstituted biphenyl, substituted or unsubstituted terphenyl, substituted or unsubstituted naphthyl, substituted or unsubstituted phenanthryl, substituted or unsubstituted triphenylene, and substituted or unsubstituted biphenylSubstituted or unsubstituted anthryl, substituted or unsubstituted dibenzofuranyl, substituted or unsubstituted dibenzothiophenyl, substituted or unsubstituted fluorenyl, and substituted or unsubstituted carbazolyl.

4. A boron-nitrogen compound according to claim 1, wherein the boron-nitrogen compound is one selected from the group consisting of compounds represented by formulae B001 to B210:

wherein, G ¹ -O-, S-, or one of the following structures:

5. an organic electroluminescent material comprising the boron-nitrogen compound according to any one of claims 1 to 4.

6. An organic electroluminescent element comprising a first electrode, a second electrode and at least one organic layer interposed between said first electrode and said second electrode, wherein said organic layer contains the boron-nitrogen compound according to any one of claims 1 to 4.

7. The organic electroluminescent element according to claim 6, wherein the organic layer comprises one or more of an electron injection layer, an electron transport layer, a hole injection layer, a hole transport layer, a hole blocking layer, an electron blocking layer and a light emitting layer.

8. The organic electroluminescent element according to claim 7, wherein the light-emitting layer further comprises a host material and a dopant material, and the host material comprises a compound consisting of the following chemical groups: triphenylene, carbazole, dibenzothiophene, dibenzofuran, dibenzoselenophene, azatriphenylene, azacarbazole, azadibenzothiophene, azadibenzofuran, azadibenzoselenophene, and triazine; the doping material contains the boron-nitrogen compound according to any one of claims 1 to 4.

9. The organic electroluminescent element according to claim 8, wherein the mass ratio of the dopant material to the host material is 1.

10. Use of the boron-nitrogen compound according to any one of claims 1 to 4 in an organic electroluminescent element.

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