CN116120350A

CN116120350A - Boron-nitrogen compound and preparation method and application thereof

Info

Publication number: CN116120350A
Application number: CN202210107044.9A
Authority: CN
Inventors: 王悦; 梁宝炎; 李成龙; 毕海
Original assignee: Jihua Hengye Foshan Electronic Materials Co ltd
Current assignee: Jihua Hengye Foshan Electronic Materials Co ltd
Priority date: 2022-01-28
Filing date: 2022-01-28
Publication date: 2023-05-16
Also published as: WO2023142486A1

Abstract

The invention provides a boron nitrogen compound, a preparation method and application thereof, wherein the boron nitrogen compound has a narrow spectrum, is used as a narrow spectrum luminescent material for preparing a luminescent layer of an organic electroluminescent device, and the prepared organic electroluminescent device realizes narrow spectrum TADF emission, and ensures that the electroluminescent external quantum efficiency of the device is more than 27 percent.

Description

Boron-nitrogen compound and preparation method and application thereof

Technical Field

The invention belongs to the technical field of organic electroluminescence, and relates to a boron-nitrogen compound and a preparation method and application thereof.

Background

The organic photoelectric material (Organic Optoelectronic Materials) is an organic material having the characteristics of generation, conversion, transmission and the like of photons and electrons. Currently, controllable photoelectric properties of Organic photoelectric materials have been applied to Organic Light-Emitting diodes (OLEDs), organic solar cells (Organic Photovoltage, OPVs), organic field effect transistors (Organic Field Effect Transistor, OFETs), and even Organic lasers. In recent years, OLEDs have become a very popular new flat display product at home and abroad. The OLED display has the characteristics of self-luminescence, wide viewing angle, short reaction time, high luminous efficiency, wide color gamut, low working voltage, thin panel, capability of manufacturing a large-size flexible panel and low cost, and is known as a star flat display product in the 21 st century.

Regarding the history of organic electroluminescence, it can be traced back to the report by Bernanose et al in 1953 (A.Bernanose, M.Comet, P.Vouaux, sur un nouveau mode d' mission lumineuse chez certains compos s organic, J.Chim.Phys.,1953, 50, 64-68), and after about 10 years, the fluorescent emission of anthracene was observed by applying a voltage to the crystals of anthracene in 1963 with Pope et al, new York university (M.Pope, H.Kallmann and P.Magnant, electroluminescence in Organic Crystals, J.chem.Phys.,1963,38,2042). In 1987, C.W.Tang et al, kodak, U.S. used an ultrathin film technique to prepare a light-emitting device with an aromatic amine having a good hole transport effect as a hole transport layer, an aluminum complex of 8-hydroxyquinoline as a light-emitting layer, and an Indium Tin Oxide (ITO) film and a metal alloy as an anode and a cathode, respectively. The device obtains brightness of up to 1000cd/m under 10V driving voltage ² The efficiency of the device was 1.5lm/W (c.w. tang and s.a. vanslyke, organic electroluminescent diodes, appl. Phys. Lett.,1987, 51, 913), a breakthrough development has led to rapid and intensive development of organic electroluminescent research worldwide. In 1990, burroughes et al, university of Cambridge, proposed the first polymer (PPV) based light emitting diode. PPV has been shown to be highly fluorescent as an emissive material in single layer devices with high luminous efficiency (burrows j.h.et al, light-emitting diodes based on conjugated polymers, nature,1990,347,539). Baldo, forrest et al, university of Princeton 1998, reported a first electroluminescent-based phosphorescent device that could in principle have an internal quantum yield of 100% (M.A.Baldo, D.F.O' brien et al, highly efficient phosphorescent emission from organic electroluminescent devices Nature,1998, 395, 151), but on the one hand, noble metals such as iridium platinum and the like are commonly used as phosphorescent materials, and on the other hand, chemical instability still exists for deep blue phosphorescent materials, and the problem that the efficiency of the device drops greatly under high current density is solved, so that it is very important to develop an OLED device which uses cheap and stable organic small molecular materials and can realize high-efficiency luminescence.

In 2012, adachi' S group reports that highly efficient fully fluorescent OLED devices based on the Thermally Activated Delayed Fluorescence (TADF) mechanism (Uoyama H, goushi K, shizu K, et al Highly efficient organic light-emitting diodes from delayed fluorescence, nature,2012,492 (7428):234-238.) can absorb thermal energy when the S1 and T1 energy levels of the molecule are sufficiently small, return to singlet state through RISC process, and thus fluoresce, and their Internal Quantum Efficiency (IQE) can theoretically reach 100%, and External Quantum Efficiency (EQE) even up to 30%, as compared to the level of shoulder phosphorescence devices. As a next-generation light-emitting material, a TADF material is being studied.

The TADF molecules are primarily doped as guest materials in a wide bandgap host material to achieve high efficiency thermally activated delayed fluorescence (Q.Zhang, J.Li, K.Shizu, et al design of Efficient Thermally Activated Delayed Fluorescence Materials for Pure Blue Organic Light Emitting Diodes, j.am. Chem. Soc.2012,134,14706; H.Uoyama, K.Goushi, K.Shizu, H.Nomura, C.Adachi, highly efficient organic light-emitting diodes from delayed fluorescence, nature,2012,492,234;T.Nishimoto,T.Yasuda,et al., a six-carbazole-decorated cyclophosphazene as a host with high triplet energy to realize efficient delayed-fluorescence OLEDs, mater.Horiz.,2014,1,264). Unlike traditional fluorescent molecular Localized (LE) state luminescence, TADF emission is mainly derived from transitions in ICT state, and is therefore susceptible to interdonor-acceptor vibration and rotational movement, resulting in a broader spectrum. The broad spectrum, while advantageous for illumination applications, does not meet the high color purity requirements of the display field. While the most important use of OLEDs is in display, narrow spectral designs (i.e., smaller full width at half maximum, FWHM) of TADF materials are necessary.

Disclosure of Invention

The invention aims to provide a boron-nitrogen compound, a preparation method and application thereof, and aims to overcome the defect of TADF luminescent molecules, provide a narrow-spectrum luminescent material and regulate and control the emission wavelength of an emission spectrum by constructing derivatives with different substituents. The boron-nitrogen heterocyclic luminescent compound based on tetraphenylene is used as a narrow spectrum luminescent material for preparing a luminescent layer of an organic electroluminescent device, and the prepared organic electroluminescent device realizes narrow spectrum TADF emission.

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

in one aspect, the present invention provides a boron nitrogen compound having a structure represented by formula I:

R ¹ and R is ² Is independently H, D (deuterium), fluorine, CN, C1-C20 alkyl, C1-C20 alkoxy, C3-C10 cycloalkyl, C6-C14 aryl, substituted with one or more R ^a Substituted C6-C18 aryl, 5-to 18-membered heteroaryl, substituted with one or more R ^a Substituted 5-to 18-membered heteroaryl, diphenylamino, or substituted with one or more R ^a Substituted diphenylamino groups;

R ⁴ is independently H, D (deuterium), fluorine, CN, C1-C20 alkyl, C1-C20 alkoxy, C3-C10 cycloalkyl, C6-C14 aryl, substituted with one or more R ^a Substituted C6-C18 aryl, 5-to 18-membered heteroaryl, substituted with one or more R ^a Substituted 5-to 18-membered heteroaryl, diphenylamino, or substituted with one or more R ^a Substituted diphenylamino groups;

R ⁵ 、R ⁶ is independently H, D (deuterium), C1-C20 alkyl, C1-C20 alkoxy, C3-C10 cycloalkyl, C6-C14 aryl, 5-to 18-membered heteroaryl;

R ^a independently at each occurrence, D (deuterium), fluorine, CN, C1-C12 alkyl, C1-C12Alkoxy, C3-C12 cycloalkyl, C6-C14 aryl, substituted by one or more R ^b Substituted C6-C14 aryl, 5-to 18-membered heteroaryl, substituted with one or more R ^b Substituted 5-to 18-membered heteroaryl, diphenylamino, or substituted with one or more R ^b Substituted diphenylamino groups;

R ^b independently at each occurrence, D (deuterium), fluorine, CN, C1-C12 alkyl, C1-C12 alkoxy, C3-C10 cycloalkyl, C6-C14 aryl, substituted with one or more R ^c Substituted C6-C14 aryl, 5-to 18-membered heteroaryl, substituted with one or more R ^c Substituted 5-to 18-membered heteroaryl, diphenylamino, or substituted with one or more R ^c Substituted diphenylamino groups;

R ^c independently for each occurrence D (deuterium), fluorine, CN, C1-C12 alkyl, C1-C12 alkoxy, C3-C10 cycloalkyl, C6-C14 aryl substituted with one or more Rd, 5-to 18-membered heteroaryl, substituted with one or more R ^d Substituted 5-to 18-membered heteroaryl, diphenylamino, or substituted with one or more R ^d Substituted diphenylamino groups;

R ^d independently at each occurrence, D (deuterium), fluorine, C1-C12 alkyl, C1-C12 alkoxy, C3-C10 cycloalkyl, C6-C14 aryl or is substituted with one or more R ^e Substituted C6-C14 aryl;

R ^e independently for each occurrence, D (deuterium), fluorine, C1-C12 alkyl, C1-C12 alkoxy, C3-C10 cycloalkyl, or C6-C14 aryl.

The alkyl, alkoxy, cycloalkyl, aryl, heteroaryl groups are optionally substituted with one or more substituents selected from the group consisting of: halogen, -CN, C1-C12 alkyl, C1-C12 alkoxy, C1-C12 haloalkyl, C2-C6 alkenyl, C3-C10 cycloalkyl, C6-C14 aryl and 5-to 18-membered heteroaryl.

In the present invention, the "alkyl, alkoxy, cycloalkyl, aryl, heteroaryl group is optionally substituted with one or more substituents selected from the group consisting of alkyl, alkoxy, cycloalkyl, aryl, heteroaryl groups, which may be unsubstituted alkyl, alkoxy, cycloalkyl, aryl or heteroaryl groups, and may also be substituted alkyl, substituted alkoxy, substituted cycloalkyl, substituted aryl or substituted heteroaryl groups, and when substituted, the substituents are selected from one or more of the recited groups (halogen, -CN, C1-C12 alkyl, C1-C12 alkoxy, C1-C12 haloalkyl, C2-C6 alkenyl, C3-C10 cycloalkyl, C6-C14 aryl and 5-to 18-membered heteroaryl).

In one embodiment, the R ¹ And R is ² Is independently H, D (deuterium), fluorine, C1-C12 alkyl, C ₁ ～C ₁₂ Alkoxy, C ₃ -C ₁₀ Cycloalkyl, phenyl, substituted with at least one C ₁ -C ₁₂ Alkyl-substituted aryl, phenyl-C ₁ ～C ₁₂ Alkyl, at least one C ₁ -C ₁₂ Alkoxy-substituted aryl, diphenylamino, substituted by at least one C ₁ -C ₁₂ Alkyl-substituted diphenylamino, carbazolyl, substituted by at least one C ₁ -C ₁₂ Alkyl-substituted carbazolyl.

In one embodiment, the R ^a Each occurrence is independently D (deuterium), fluorine, C ₁ ～C ₁₂ Alkyl, C ₁ ～C ₁₂ Alkoxy, C ₃ -C ₁₀ Cycloalkyl, at least one C ₁ -C ₁₂ Alkyl-substituted phenyl, phenyl-C ₁ ～C ₁₂ Alkyl, at least one C ₁ -C ₁₂ Alkoxy-substituted phenyl, diphenylamino, substituted by at least one C ₁ -C ₁₂ Alkyl-substituted diphenylamino, carbazolyl, substituted by at least one C ₁ -C ₁₂ Alkyl-substituted carbazolyl.

In one embodiment, the R ^b Each occurrence is independently D (deuterium), fluorine, C ₁ ～C ₁₂ Alkyl, C ₁ ～C ₁₂ Alkoxy, C ₃ -C ₁₀ Cycloalkyl, at least one C ₁ -C ₁₂ Alkyl-substituted phenyl, phenyl-C ₁ ～C ₁₂ Alkyl, at least one C ₁ -C ₁₂ Alkoxy-substituted phenyl, diphenylamino, substituted by at least one C ₁ -C ₁₂ Alkyl-substituted diphenylamino, carbazolyl, substituted by at least one C ₁ -C ₁₂ Alkyl-substituted carbazolyl.

In one embodiment, the R ^c Each occurrence is independently D (deuterium), fluorine, C ₁ ～C ₁₂ Alkyl, C ₁ ～C ₁₂ Alkoxy, C ₃ -C ₁₀ Cycloalkyl, at least one C ₁ -C ₁₂ Alkyl-substituted phenyl, phenyl-C ₁ ～C ₁₂ Alkyl, at least one C ₁ -C ₁₂ Alkoxy-substituted phenyl, diphenylamino, substituted by at least one C ₁ -C ₁₂ Alkyl-substituted diphenylamino, carbazolyl, substituted by at least one C ₁ -C ₁₂ Alkyl-substituted carbazolyl.

In one embodiment, the R ^d Each occurrence is independently D (deuterium), fluorine, C ₁ ～C ₁₂ Alkyl, C ₁ ～C ₁₂ Alkoxy, C ₃ -C ₁₀ Cycloalkyl, at least one C ₁ -C ₁₂ Phenyl substituted by alkyl, substituted by at least one C ₁ -C ₁₂ Phenyl substituted by alkoxy, carbazolyl, substituted by at least one C ₁ -C ₁₂ Alkyl-substituted carbazolyl.

In one embodiment, the R ¹ And R is ² H, D (deuterium), fluorine, methyl, ethyl, n-propyl, isopropyl, n-butyl, tert-butyl, hexyl, octyl, decyl,

Methoxy, ethoxy, butoxy, hexyloxy,

Cyclohexyl, adamantyl, phenyl, 4-methyl-phenyl, 4-ethyl-phenyl, 4-propyl-phenyl, 4-isopropylphenyl, 4-n-butylphenyl,/->

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Wherein the wavy line represents the attachment site of the group.

In some preferred embodiments, the R ¹ And R is ² Independently H, methyl,

Phenyl group,/->

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Wherein the wavy line represents the attachment site of the group.

In some preferred embodiments, the R ¹ And R is ² The same is selected from H, methyl,

Phenyl group,/->

Any one of them;

wherein R is ^g Is H, methyl, isopropyl, tert-butyl or

In some preferred embodiments, R ⁴ H, C1 to C8 alkyl, C6 to C12 aryl, C5 to C18 heteroaryl, R ^f Substituted C6-C12 aryl or R ^f SubstitutedC5-C18 heteroaryl;

R ^f d (deuterium), fluorine, methyl, ethyl, n-propyl, isopropyl, n-butyl, tert-butyl, hexyl, octyl, decyl,

Methoxy, ethoxy, butoxy, hexyloxy, < >>

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Wherein the wavy line represents the attachment site of the group.

In some preferred embodiments, the R ^f Is H, methyl,

Phenyl group,/->

Wherein the wavy line represents the attachment site of the group.

In some preferred embodiments, the R ⁴ Is H, methyl,

Phenyl group,/->

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R ^h Is H, methyl, tert-butyl or +.>

In some preferred embodiments, R ⁵ H, C1 to C8 alkyl, C6 to C18 aryl or C5 to C18 heteroaryl.

In some preferred embodiments, R ⁶ Is H or methyl.

In some embodiments of the invention, the boron nitrogen compound is any one of the following compounds:

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in another aspect, the present invention provides a method for preparing a boron nitrogen compound as described above, comprising the steps of:

(1) In the presence of a catalyst, the compound BN-Bpin reacts with the compound B to obtain a compound BN-DBTn, and the reaction formula is as follows:

(2) The compound BN-DBTn undergoes a ring closure reaction in the presence of ferric trichloride to obtain a boron-nitrogen compound shown in a formula I, wherein the reaction formula is as follows:

preferably, the molar ratio of the compound BN-Bpin of step (1) to the compound B is from 1:0.8 to 2, such as 1:0.8, 1:1, 1:1.2, 1:1.5, 1:1.8 or 1:2.

Preferably, the reaction of step (1) is carried out in the presence of a weakly basic substance;

preferably, the weakly basic material is potassium carbonate;

preferably, the catalyst of step (1) is tetrakis (triphenylphosphine) palladium;

preferably, the catalyst of step (1) is used in an amount of 0.1% to 15%, such as 0.2%, 0.5%, 1%, 3%, 5%, 8%, 10%, 12% or 15% of the amount of the substance of the compound BN-Bpin.

Preferably, the solvent of the reaction of step (1) is tetrahydrofuran;

Preferably, the reaction of step (1) is carried out under reflux;

preferably, the time of the reaction of step (1) is from 5 to 24 hours, for example 5 hours, 8 hours, 10 hours, 12 hours, 15 hours, 18 hours, 20 hours, 22 hours or 24 hours.

Preferably, the dosage of the ferric trichloride in the step (2) is 3-50 times of the dosage of the BN-Dpn compound;

preferably, the solvent for the ring closure reaction in step (2) is dichloromethane;

preferably, the ring closure reaction of step (2) is carried out at room temperature;

preferably, the time of the ring closure reaction of step (2) is from 0.5 to 12 hours, for example 0.5 hours, 1 hour, 3 hours, 5 hours, 8 hours, 10 hours or 12 hours.

Preferably, the reactions of step (1) and step (2) are carried out under nitrogen protection.

In another aspect, the present invention provides an organic electroluminescent material comprising a boron-nitrogen heterocyclic luminescent compound of triphenylene as described above.

In another aspect, the present invention provides an organic electroluminescent device comprising an anode and a cathode and an organic thin film layer interposed between the anode and the cathode, the organic thin film layer comprising a light emitting layer, an optional hole injection layer, an optional hole transport layer, an optional electron injection layer, wherein at least one of the light emitting layer, the electron injection layer, the electron transport layer, the hole injection layer comprises a boron nitride compound as described above.

In the invention, the boron nitrogen heterocyclic luminous compound containing tetraphenylene with the structure shown in the formula I can be used as a functional material in at least one layer of a luminous layer, an electron injection layer, an electron transport layer, a hole transport layer and a hole injection layer of an organic electroluminescent device.

In one embodiment, the organic electroluminescent device of the present invention may further comprise an optional hole blocking layer, an optional electron blocking layer, an optional capping layer, and the like.

In one embodiment, the organic electroluminescent device has a structure as shown in fig. 1, wherein 1 is an ITO anode, 2 is a hole injection layer, 3 is a hole transport layer, 4 is a light emitting layer, 5 is an electron transport layer, 6 is an electron injection layer, and 7 is a metal cathode.

In one embodiment, the boron nitrogen heterocyclic luminescent compound of tetraphenylene with the structure shown in the formula I is used for preparing a luminescent layer in an organic electroluminescent device.

In one embodiment, the organic electroluminescent device further comprises a substrate, and an anode layer, an organic light-emitting functional layer and a cathode layer sequentially formed on the substrate; the organic light-emitting functional layer comprises a light-emitting layer containing the boron-nitrogen compound, and can further comprise any one or a combination of a plurality of hole injection layer, a hole transport layer, an electron blocking layer, a hole blocking layer, an electron transport layer and an electron injection layer.

In another aspect, the present invention provides an organic electroluminescent composition comprising a boron nitride compound as described above as a doping material and a host material;

preferably, the host material is a material having an electron transport ability and/or a hole transport ability and having a triplet excited state energy higher than or equal to that of the dopant material.

In one embodiment of the present invention, the host material in the organic electroluminescent composition is a carbazole derivative and/or carboline derivative having a structure represented by any one of the formulae (H-1) to (H-6):

wherein X is ₁ 、Y ₁ And Z ₁ Is CH or N, and X ₁ 、Y ₁ And Z ₁ At most one of which is N.

Wherein R is ^1H And R is ^2H Independently any of the following groups:

wherein X is ₁ 、Y ₁ And Z ₁ Is CH or N, and X ₁ 、Y ₁ And Z ₁ At most one of them is N;

wherein R is ^aH And R is ^bH H, C independently ₁ -C ₂₀ Alkyl, C ₁ -C ₂₀ Alkoxy, C ₆ -C ₂₀ Aryl, C ₁ -C ₂₀ Alkyl substituted C ₆ -C ₂₀ Aryl or C ₁ -C ₂₀ Alkoxy substituted C ₆ -C ₂₀ Aryl, number represents the attachment site of the group.

In one embodiment of the present invention, the organic electroluminescent composition preferably contains 0.3 to 30.0wt% (wt%) of the boron-nitrogen heterocyclic light-emitting compound of triphenylene having the structure shown in formula I as described above as a doping material, and the remaining 99.7 to 70.0wt% of the organic electroluminescent composition is a host material composed of 1 to 2 compounds having the structures of formulae (H-1) to (H-6).

In one embodiment of the invention, the host material contains 2 compounds having the structures of formula (H-1) to formula (H-6) in a weight ratio of 1:5 to 5:1, such as 1:5, 1:4, 1:3, 1:2, 1:1, 2:1, 3:1, 4:1, 5:1, etc.

In one embodiment of the present invention, the host material in the organic electroluminescent composition is 1-2 of the compounds H1-1 to H1-427.

In one embodiment of the present invention, the organic electroluminescent composition comprises 0.3 to 30.0wt% of the boron-nitrogen heterocyclic luminescent compound of triphenylene having the structure shown in formula I as described above, and the remaining 99.7 to 70.0wt% of the boron-nitrogen heterocyclic luminescent compound is 1 or 2 of the compounds H1-1 to H1-427.

In a preferred embodiment of the present invention, the organic electroluminescent composition comprises 2 compounds of the compounds H1-1 to H1-427 as host materials in a weight ratio of 1:5 to 5:1, such as 1:5, 1:4, 1:3, 1:2, 1:1, 2:1, 3:1, 4:1, 5:1, etc.

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In one embodiment of the invention, the doping material in the organic electroluminescent composition is any one (the content is 0.3-30.0 wt%) of boron-nitrogen heterocyclic luminescent compound of triphenylene with the structure shown in the formula I; the main body material (content of 99.7wt% -70.0wt%) is composed of any one of compounds shown as formula Trz1-A, trz2-A, trz3-A, trz4-A, trz5-A or Trz6-A and any one of compounds with structures shown as formulas H-1 to H-6.

In a preferred embodiment, the weight ratio between the compound indicated by Trz1-A, trz2-A, trz3-A, trz4-A, trz5-A or Trz6-A and the compound indicated by H-1, H-2, H-3, H-4, H-5 or H-6 in the host material is from 1:5 to 5:1, such as 1:5, 1:4, 1:3, 1:2, 1:1, 2:1, 3:1, 4:1, 5:1, etc.

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Wherein R is ^1a 、R ^1b 、R ^2a 、R ^2b 、R ^3a And R is ^3b Wherein 1 or 2 are independently R ^Tz The remainder being the same or different and independently hydrogen, deuterium, C ₁ -C ₈ Alkyl, C ₁ -C ₈ Alkoxy, C ₆ -C ₁₈ Aryl, C ₁ -C ₈ Alkyl substituted C ₆ -C ₁₈ Aryl or C ₁ -C ₈ Alkoxy substituted C ₆ -C ₁₈ Aryl of (a); r is R ^Tz Is any one of substituent groups shown in the following formula:

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wherein asterisks indicate the attachment site of the group.

In one embodiment of the present invention, the doping material in the organic electroluminescent composition is any one of boron-nitrogen compounds (the content is 0.3 wt% to 30.0 wt%) with the structure shown in the formula I; the main material (the content is 99.7wt% -70.0wt%) is composed of any one of compounds shown as formulas TRZ-1 to TRZ-76 and any one of carbazole or carboline derivatives shown as formulas H1-1 to H1-427.

In a preferred embodiment, the weight ratio between the compound of formulae TRZ-1 to TRZ-76 and the carbazole or carboline derivative in the host material is 1:5 to 5:1, e.g. 1:5, 1:4, 1:3, 1:2, 1:1, 2:1, 3:1, 4:1, 5:1, etc.

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In another aspect, the present invention provides an organic electroluminescent material comprising an organic electroluminescent composition as described above.

In another aspect, the present invention provides an organic electroluminescent device comprising an anode and a cathode and an organic thin film layer interposed between the anode and the cathode, the organic thin film layer comprising a light emitting layer, an optional hole injection layer, an optional hole transport layer, an optional electron injection layer, wherein at least one of the light emitting layer, the electron injection layer, the electron transport layer, the hole injection layer comprises the organic electroluminescent composition as described above.

In the present invention, the organic electroluminescent composition may be used as a functional material in at least one of a light emitting layer, an electron injection layer, an electron transport layer, a hole transport layer, and a hole injection layer of an organic electroluminescent device.

In a certain embodiment of the invention, the material of the light emitting layer in the organic electroluminescent device comprises an organic electroluminescent composition as described above.

In one embodiment of the present invention, the organic electroluminescent composition is a light-emitting layer, and the light-emitting principle of the light-emitting layer is based on energy transfer from a host material to any of the compounds represented by formula I or carrier capture by the light-emitting material itself.

In one embodiment of the invention, the organic electroluminescent composition is a light-emitting layer; the host material in the organic electroluminescent composition may be a carbazole derivative and/or a carboline derivative represented by the formulae (H-1) to (H-6). In a preferred embodiment, the organic electroluminescent composition comprises 0.3 to 30.0wt% of any one of the compounds represented by formula I, and the remaining 99.7 to 70.0wt% of the composition is a host composed of 1 to 2 compounds having the structures of formulae (H-1) to (H-6). For example, when the host contains 2 compounds having the structures of formulas (H-1) to (H-6), the weight ratio of the two compounds is 1:5 to 5:1.

In one embodiment of the invention, the organic electroluminescent composition is a light-emitting layer; the main materials in the composition are 1-2 of the compounds H1-1 to H1-427. In a preferred embodiment, the organic electroluminescent composition comprises 0.3-30.0wt% of any one of the compounds of formula I or formula II, and the remaining 99.7-70.0wt% of the composition is 1-2 of the compounds H1-1 to H1-427. For example, when 2 compounds of formulas H1-1 to H1-427 are included in the composition, the weight ratio of the two compounds is 1:5 to 5:1.

In one embodiment of the invention, the organic electroluminescent composition is a light-emitting layer; the doping material in the organic electroluminescent composition is any compound shown in the formula I (the content is 0.3-30.0 wt%); the main body material (content of 99.7wt% -70.0wt%) is composed of any one of the compounds shown as the formula Trz1-A, trz2-A, trz3-A, trz4-A, trz5-A or Trz6-A and any one of the compounds shown as the formulas H-1 to H-6. For example, in the host material, the weight ratio of Trz1-A, trz2-A, trz3-A, trz4-A, trz5-A or Trz6-A compound to the compound of H-1, H-2, H-3, H-4, H-5 or H-6 is 1:5 to 5:1.

In one embodiment of the invention, the organic electroluminescent composition is a light-emitting layer; the doping material in the organic electroluminescent composition is any compound shown in the formula I (the content is 0.3-30.0 wt%); the main material (content of 99.7wt% -70.0wt%) is composed of any one of 1,3, 5-triazine derivatives shown in formulas TRZ-1 to TRZ-76 and any one of carbazole or carboline derivatives shown in formulas H1-1 to H1-427. For example, in the host material, the weight ratio between the 1,3, 5-triazine derivative and the carbazole or carboline derivative is 1:5 to 5:1.

In one embodiment of the invention, the organic electroluminescent composition is a light-emitting layer; the doping material in the organic electroluminescent composition is any one compound (the content is 0.3-30.0 wt%) shown in the formulas BN 1-BN 180; the main body material (the content is 99.7wt% -70.0wt%) is composed of any one of the compounds shown as the formula Trz1-A, trz2-A, trz3-A, trz4-A, trz5-A and Trz6-A and any one of carbazole or carboline derivatives shown as the formulas H1-1 to H1-427. For example, in the host materials, the weight ratio between the compounds of formulae Trz1-A, trz2-A, trz3-A, trz4-A, trz5-A, and Trz6-A, and carbazole or carboline derivatives of formulae H1-1 to H1-427 is 1:5 to 5:1.

In one embodiment of the present invention, the organic electroluminescent device further comprises a substrate, and an anode layer, an organic light-emitting functional layer and a cathode layer sequentially formed on the substrate; the organic light-emitting functional layer comprises a light-emitting layer containing the organic electroluminescent composition, and can also comprise any one or a combination of at least two of a hole injection layer, a hole transport layer, an electron blocking layer, a hole blocking layer, an electron transport layer and an electron injection layer.

In another aspect, the invention provides an application of the organic electroluminescent device in an organic electroluminescent display or an organic electroluminescent illumination source.

Description of the terms

Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs.

As used herein, the term "comprising" or "including" can be open, semi-closed, and closed. In other words, the term also includes "consisting essentially of …," or "consisting of ….

Definition of groups

In this specification, groups and substituents thereof can be selected by one skilled in the art to provide stable moieties and compounds. When substituents are described by conventional formulas written from left to right, the substituents also include chemically equivalent substituents obtained when writing formulas from right to left.

The section headings used in this specification are for organizational purposes only and are not to be construed as limiting the subject matter described. All documents or portions of documents cited in this disclosure, including but not limited to patents, patent applications, articles, books, operating manuals, and treatises, are hereby incorporated by reference in their entirety.

Unless otherwise specified, all technical and scientific terms used herein have the standard meaning of the art to which the claimed subject matter belongs. In case there are multiple definitions for a term, the definitions herein control.

As used herein, the singular forms "a", "an", and "the" are understood to include plural referents unless the context clearly dictates otherwise. Furthermore, the term "comprising" is an open-ended limitation and does not exclude other aspects, i.e. it includes the content indicated by the invention.

Unless otherwise indicated, the present invention employs conventional methods of mass spectrometry, elemental analysis, and the various steps and conditions are referred to in the art by conventional procedures and conditions.

The present invention employs, unless otherwise indicated, standard nomenclature for analytical chemistry, organic synthetic chemistry and optics, and standard laboratory procedures and techniques. In some cases, standard techniques are used for chemical synthesis, chemical analysis, and light emitting device performance detection.

The compounds of the present invention may contain non-natural proportions of atomic isotopes on one or more of the atoms comprising the compounds. For example, compounds such as deuterium (2H) may be labeled with a radioisotope. All isotopic variations of the compounds of the present invention, whether radioactive or not, are intended to be encompassed within the scope of the present invention.

In the present invention, the number of "substitutions" may be one or more unless otherwise specified; when plural, it means two or more, for example, may be 2, 3 or 4. In addition, when the number of "substitutions" is plural, the "substitutions" may be the same or different. In the present invention, the "substituted" position may be any position unless otherwise specified.

In the present invention, as part of a group or other groups (e.g., as used in halogen-substituted alkyl groups and the like), the term "alkyl" is meant to include both branched and straight-chain saturated aliphatic hydrocarbon groups having the indicated number of carbon atoms. For example, C ₁ ～C ₂₀ Alkyl groups include straight or branched chain alkyl groups having 1 to 20 carbon atoms. As in "C ₁ ～C ₆ Alkyl "is defined to include in straight or branched chain linkagesA group having 1, 2, 3, 4, 5, or 6 carbon atoms in the structure. For example, in the present invention, the C1-C6 alkyl groups are each independently methyl, ethyl, propyl, butyl, pentyl or hexyl; wherein propyl is C3 alkyl (including isomers such as n-propyl or isopropyl); butyl is C4 alkyl (including isomers such as n-butyl, sec-butyl, isobutyl, or tert-butyl); pentyl is C5 alkyl (including isomers such as n-pentyl, 1-methyl-butyl, 1-ethyl-propyl, 2-methyl-1-butyl, 3-methyl-1-butyl, isopentyl, t-pentyl or neopentyl); hexyl is C6 alkyl (including isomers such as n-hexyl or isohexyl).

The term "alkoxy" as used herein refers to an alkyl group as defined above, each attached via an oxygen bond (-O-).

In the present invention, the term "Cn-m aryl" as part of a group or other group refers to a monocyclic or polycyclic aromatic group having n to m ring carbon atoms (the ring atoms being carbon atoms only) having at least one carbocyclic ring with a conjugated pi-electron system. Examples of the above aryl unit include phenyl, naphthyl, indenyl, azulenyl, fluorenyl, phenanthryl, or anthracyl. In one embodiment, the aryl group is preferably a C6-14 aryl group, such as phenyl and naphthyl, more preferably phenyl.

In the present invention, the term "n-m membered heteroaryl" as part of a group or other group means an aromatic group having one or more (e.g., 1, 2, 3 and 4) heteroatoms selected from nitrogen, oxygen and sulfur, having from n to m ring atoms, said heteroaryl being a monocyclic, bicyclic, tricyclic or tetracyclic ring system, wherein at least one ring is an aromatic ring. Heteroaryl groups within the scope of this definition include, but are not limited to: acridinyl, carbazolyl, cinnolinyl, quinoxalinyl, pyrazolyl, indolyl, benzotriazole, furanyl, thienyl, benzothienyl, benzofuranyl, quinolinyl, isoquinolinyl, oxazolyl, isoxazolyl, pyrazinyl, pyridazinyl, pyridyl, pyrimidinyl, pyrrolyl, tetrahydroquinolinyl, imidazolyl, triazolyl, tetrazolyl, thiazolyl, isothiazolyl, furazanyl, thiadiazolyl, oxadiazolyl, pyridyl, pyrazinyl, pyridazinyl, pyrimidinyl, triazinyl, purinyl, pteridinyl, naphthyridinyl, quinazolinyl, phthalazinyl, imidazopyridinyl, imidazothiazolyl, imidazooxazolyl, benzothiazolyl, benzoxazolyl, benzimidazolyl, isoindolyl, indazolyl, pyrrolopyridinyl, thienopyridinyl, benzothiadiazolyl, benzoxadiazolyl, pyrrolopyrimidinyl, thienofuranyl. In one embodiment, as preferable examples of the "5-to 18-membered heteroaryl group", furyl, thienyl, pyrrolyl, imidazolyl, thiazolyl, pyrazolyl, oxazolyl, isoxazolyl, isothiazolyl, pyridyl, pyrimidinyl and carbazolyl groups are cited, and carbazolyl groups are more preferable.

The term Cn-Cm cycloalkyl as used herein refers to mono-or multicyclic alkyls having from n to m carbon atoms, such as 3-C10 cycloalkyl and C3-C6 cycloalkyl. Examples include adamantyl, cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, cycloheptyl and bicycloheptyl. In one embodiment, the C3-C10 cycloalkyl is preferably adamantyl or cyclohexyl.

The definition of a carbon number range for a group as described in the present invention means that any integer included in the definition, such as C, of carbon atoms ₁ ～C ₂₀ It is meant that the number of carbon atoms of the radical may be 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19 or 20, C ₃ -C ₁₀ It is meant that the number of carbon atoms of the group may be 3, 4, 5, 6, 7, 8, 9 or 10, and so on for the other groups.

The above preferred conditions can be arbitrarily combined on the basis of not deviating from the common knowledge in the art, and thus, each preferred embodiment of the present invention can be obtained.

The reagents and materials used in the present invention are commercially available.

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

the boron nitride compound adopts a binuclear strategy to realize effective red shift of a BN derivative spectrum, has a narrow spectrum, is used as a narrow spectrum luminescent material for preparing a luminescent layer of an organic electroluminescent device, realizes narrow spectrum TADF emission, and ensures that the electroluminescent external quantum efficiency of the device is up to more than 24 percent.

Drawings

Fig. 1 is a schematic structural diagram of an organic electroluminescent device according to the present invention, wherein 1 is an ITO anode, 2 is a hole injection layer, 3 is a hole transport layer, 4 is a light emitting layer, 5 is an electron transport layer, 6 is an electron injection layer, and 7 is a metal cathode.

FIG. 2 shows the result of the reaction of Compound BN31 in toluene (concentration: 1X 10) ^-5 M) photoluminescence spectrum in the sample.

FIG. 3 is an electroluminescent spectrum of the compound BN 31.

Detailed Description

The technical scheme of the invention is further described by the following specific embodiments. It will be apparent to those skilled in the art that the examples are merely to aid in understanding the invention and are not to be construed as a specific limitation thereof.

In the examples of the present invention, the starting materials used for the synthesis of the indicated compounds were as follows:

the raw materials BXX adopted are as follows

The invention is further illustrated by means of the following representative examples, which are not intended to limit the invention to the examples described. The experimental methods, in which specific conditions are not noted in the following examples, were selected according to conventional methods and conditions, or according to the commercial specifications.

The basic process route of the compound synthesis related by the invention is as follows:

the preparation method comprises the steps of taking BN-Bpin as a substrate, firstly coupling a simple Suzuki reaction with (not) monobromobiphenyl compounds containing various substituents to obtain a precursor, and then carrying out classical scholl oxidative coupling in the presence of ferric trichloride to obtain a final product. The specific synthesis process comprises the following steps:

In the first step, 2 '-iodo-1, 1':3',1' -triphenyls (B1-B15) (0.6 mmol), 383mg BN-Bpin (0.5 mmol), 0.14g potassium carbonate (1 mmol) and water (2 mL) were added to tetrahydrofuran (16 mL), the mixture was bubbled with nitrogen for 10 min, and 28.9mg tetrakis (triphenylphosphine) palladium (0.025 mmol) was added under high flow of nitrogen. The mixture was heated to reflux and stirred for 12 hours. After the reaction system was cooled to room temperature, the reaction mixture was extracted with dichloromethane and water, the organic phase was dried by heating under vacuum, and then purified by column chromatography to obtain the precursor BN-DBTn (n=1-180).

In a second step, 0.3mmol BN-DBTn (A1-A12) is dissolved in 50mL ultra-dry dichloromethane and 1.12g ferric trichloride is dissolved in 10mL nitromethane. Liquid nitrogen is degassed and displaced for 30min. The nitromethane mixture was slowly added dropwise under an ice water bath, and then slowly warmed to room temperature, and the reaction was continued for 2 hours. The reaction was quenched by addition of 5mL of methanol and 5mL of water, the reaction mixture was extracted with dichloromethane and water, the organic phase was dried by heating under vacuum, and then purified by column chromatography to give the desired product BNn (n=1-180). The data obtained for the target compounds are shown in Table 1.

Experimental details of the synthetic examples are illustrated by compound BN 31:

In the first step 214mg of 2 '-iodo-1, 1':3',1' -triphenylCompound (0.6 mmol), 383mg BN-Bpin (0.5 mmol), 0.14g Potassium carbonate (1 mmol) and water (2 mL) were added to tetrahydrofuran (16 mL), the mixture was bubbled with nitrogen for 10 min, and 28.9mg tetrakis (triphenylphosphine) palladium (0.025 mmol) was added under high flow of nitrogen. The mixture was heated to reflux and stirred for 12 hours. After the reaction system was cooled to room temperature, the reaction mixture was extracted with dichloromethane and water, the organic phase was dried by heating under vacuum, and then purified by column chromatography to obtain the precursor BN-DPT31.

In a second step, 260mg of BN-DPT31 (0.3 mmol) is dissolved in 50mL of ultra-dry dichloromethane and 1.12g of ferric trichloride is dissolved in 10mL of nitromethane. Liquid nitrogen is degassed and displaced for 30min. The nitromethane mixture was slowly added dropwise under an ice water bath, and then slowly warmed to room temperature, and the reaction was continued for 2 hours. The reaction mixture was extracted with dichloromethane and water, and the organic phase was dried by heating under vacuum, followed by purification by column chromatography to give the desired product BN31.

The product was characterized in that the elemental analysis used a test instrument of Vario Micro Cube from Agilent, U.S.A., test element types were: C. h, N, S. The instrument used for mass spectrometry is a triple quadrupole mass spectrometer in tandem with ultra high performance liquid chromatography in U.S. Thermo Fisher TSQ Endura.

TABLE 1 summary of synthetic example product data

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Electroluminescent device embodiment

Some representative electroluminescent device embodiments are given below, and some of the material molecular structures involved in the device embodiments are as follows:

the following embodiment of electroluminescent devices prepared by using the material of the present invention, the specific device preparation process is as follows:

(1) And (3) substrate processing: the transparent ITO glass is used as a substrate material for preparing devices, is subjected to ultrasonic treatment for 30min by using 5% ITO washing liquid, is sequentially subjected to ultrasonic washing by using distilled water (2 times), acetone (2 times) and isopropanol (2 times), and is finally stored in isopropanol. Before each use, the surface of the ITO glass is carefully wiped by acetone cotton balls and isopropanol cotton balls, and after the isopropanol is washed, the ITO glass is dried, and then is treated by plasma for 5min for standby. The preparation of the device is completed by combining spin coating and vacuum evaporation process.

(2) Hole injection lamination hole transport layer preparation: a layer of 20nm thick PEDOT PSS (Poly 3, 4-ethylenedioxythiophene) polystyrene sulfonate, which is commercially available from Heraeus Corp. Germany, was first spin-coated on the ITO surface as a hole injection layer, then a 50nm thick Poly-HTL was spin-coated on the hole injection layer as a hole transport layer, and then the ITO glass with the hole injection layer and the hole transport layer was annealed at 200℃for 30 minutes in a nitrogen-protected glove box (cross-linking the Poly-HTL).

(3) Preparing a light-emitting layer: the main material and the luminescent material are dissolved in dimethylbenzene according to the proportion of 97wt% (weight percent concentration) to prepare a solution with the concentration of 2wt%, and the prepared solution is used for preparing the luminescent layer by spin coating, wherein the thickness of the luminescent layer is 50nm.

(4) Preparation of an electron transport layer, an electron injection layer and a metal electrode: an electron transport layer, an electron injection layer and a metal electrode are prepared by adopting an evaporation process, and when the vacuum degree of a vacuum evaporation system reaches 5 multiplied by 10 ^-4 Starting vapor deposition when Pa is lower, and sequentially depositing the vapor deposition rate on the luminous layer by using a Saint film thickness instrument and a vacuum vapor deposition processAn organic electron transport layer, a LiF electron injection layer, and a metallic Al electrode (see the following effect examples for specific device structures). Wherein the deposition rate of the organic material is

Deposition rate of LiF->

The deposition rate of Al is->

Device examples A1 to A108

In the organic electroluminescent device (structure shown in FIG. 1) in device examples A1-A108, PEDOT: PSS was used as a hole injection layer, poly-HTL was used as a hole transport layer, H1-48 was used as a host material in a light emitting layer, BN-1 to BN-618 were respectively used as doped light emitting materials (doping concentration was 2 wt%), tmPyPB was used as an electron transport material, liF was used as an electron injection layer, and Al was used as a metal cathode. Effect example the organic electroluminescent device structure was [ ITO/PEDOT: PSS (20 nm)/Poly-HTL (50 nm)// H1-33+3wt% bnn/TRZ-8 (50 nm)/LiF (1 nm)/Al (100 nm) ].

The current, voltage, brightness, luminescence spectrum and other characteristics of the device were synchronously tested using a Photo Research PR 655 spectral scanning luminance meter and a Keithley K2400 digital source meter system. The performance test of the device was performed at room temperature under ambient atmosphere. The External Quantum Efficiency (EQE) of the device is calculated from the current density, brightness and electro-spectral combined with the visual function in the case of the light emission as a langerhans distribution.

The test results are shown in Table 2.

TABLE 2

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The electroluminescent device effect implementation data listed in table 2 prove that the luminescent material provided by the invention can be used for preparing high-efficiency organic electroluminescent devices, and the electroluminescent spectrum has narrow band characteristics, the half-peak width of the electroluminescent spectrum is less than or equal to 56nm, and the electroluminescent external quantum efficiency is as high as more than 27%.

And wherein the compound BN31 is present in a toluene solution (concentration: 1X 10 ^-5 M) (i.e., fluorescence spectrum, excitation wavelength 365nm as measured by FLS980 fluorescence spectrometer) as shown in fig. 2, it can be seen from fig. 2 that the luminescence peak position is 560nm and the half-width is 52nm.

FIG. 3 shows the electroluminescent spectrum of the compound BN31 (obtained by measuring with a Photo Research PR 655 spectroscanning luminance meter), which is shown in FIG. 3, and has a luminescence peak position of 559nm and a half-width of 48nm.

Device examples B1 to B108

In the organic electroluminescent device in device examples B1 to B108, in the organic electroluminescent device (structure shown in FIG. 1) in effect example 2, PEDOT: PSS was used as a hole injection layer, poly-HTL was used as a hole transport layer, a mixture of H1-33 and TRZ-8 in a light emitting layer was used as a host material (weight mixing ratio of H1-33 to TRZ-8 was 1:1), BNn was used as a doped light emitting material (doping concentration was 3 wt%), TRZ-8 was used as an electron transport material, liF was used as an electron injection layer, and Al was used as a metal cathode, respectively. Effect example the organic electroluminescent device structure was [ ITO/PEDOT: PSS (20 nm)/Poly-HTL (50 nm)/H1-33:trz-8+3wt% bnn/TRZ-8 (50 nm)/LiF (1 nm)/Al (100 nm) ].

The effect of the device was also tested, the peak position and half-width of the electroluminescent spectrum, and the electroluminescent external quantum efficiency were tested, and the test results are shown in table 3.

TABLE 3 Table 3

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The electroluminescent device effect implementation data listed in table 3 prove that the luminescent material provided by the invention can be used for preparing high-efficiency organic electroluminescent devices, and the electroluminescent spectrum has narrow band characteristics, the half-peak width of the electroluminescent spectrum is less than or equal to 55nm, and the electroluminescent external quantum efficiency is as high as more than 27%.

The applicant states that the present invention is illustrated by the above examples of boron nitride compounds of the present invention and their use, but the present invention is not limited to the above examples, i.e. it is not meant that the present invention must be practiced in dependence upon the above examples. It should be apparent to those skilled in the art that any modification of the present invention, equivalent substitution of selected raw materials, addition of auxiliary components, selection of specific modes, etc. fall within the scope of the present invention and the scope of disclosure.

Claims

1. A boron nitride compound, characterized in that the boron nitride compound has a structure represented by formula I:

R ¹ and R is ² Is independently H, deuterium, fluorine, CN, C1-C20 alkyl, C1-C20 alkoxy, C3-C10 cycloalkyl or C6-overC14 aryl, substituted by one or more R ^a Substituted C6-C18 aryl, 5-to 18-membered heteroaryl, substituted with one or more R ^a Substituted 5-to 18-membered heteroaryl, diphenylamino, or substituted with one or more R ^a Substituted diphenylamino groups;

R ⁴ independently H, deuterium, fluorine, CN, C1-C20 alkyl, C1-C20 alkoxy, C3-C10 cycloalkyl, C6-C14 aryl, substituted with one or more R ^a Substituted C6-C18 aryl, 5-to 18-membered heteroaryl, substituted with one or more R ^a Substituted 5-to 18-membered heteroaryl, diphenylamino, or substituted with one or more R ^a Substituted diphenylamino groups;

R ⁵ 、R ⁶ independently H, deuterium, C1-C20 alkyl, C1-C20 alkoxy, C3-C10 cycloalkyl, C6-C14 aryl, 5-to 18-membered heteroaryl;

R ^a independently at each occurrence deuterium, fluorine, CN, C1-C12 alkyl, C1-C12 alkoxy, C3-C12 cycloalkyl, C6-C14 aryl, substituted with one or more R ^b Substituted C6-C14 aryl, 5-to 18-membered heteroaryl, substituted with one or more R ^b Substituted 5-to 18-membered heteroaryl, diphenylamino, or substituted with one or more R ^b Substituted diphenylamino groups;

R ^b independently at each occurrence deuterium, fluorine, CN, C1-C12 alkyl, C1-C12 alkoxy, C3-C10 cycloalkyl, C6-C14 aryl, substituted with one or more R ^c Substituted C6-C14 aryl, 5-to 18-membered heteroaryl, substituted with one or more R ^c Substituted 5-to 18-membered heteroaryl, diphenylamino, or substituted with one or more R ^c Substituted diphenylamino groups;

R ^c independently for each occurrence deuterium, fluorine, CN, C1-C12 alkyl, C1-C12 alkoxy, C3-C10 cycloalkyl, C6-C14 aryl substituted with one or more Rd, 5-to 18-membered heteroaryl, substituted with one or more R ^d Substituted 5-to 18-membered heteroaryl, diphenylamino, or substituted with one or more R ^d Substituted diphenylamino groups;

R ^d independently at each occurrence deuterium, fluorine, C1-C12 alkyl, C1-C12 alkoxy, C3-C10 ringAlkyl, C6-C14 aryl or substituted by one or more R ^e Substituted C6-C14 aryl;

R ^e each occurrence is independently deuterium, fluorine, C1-C12 alkyl, C1-C12 alkoxy, C3-C10 cycloalkyl, or C6-C14 aryl.

2. The boron nitride according to claim 1, wherein said R ¹ And R is ² Independently H, deuterium, fluorine, C1-C12 alkyl, C ₁ ～C ₁₂ Alkoxy, C ₃ -C ₁₀ Cycloalkyl, phenyl, substituted with at least one C ₁ -C ₁₂ Alkyl-substituted aryl, phenyl-C ₁ ～C ₁₂ Alkyl, at least one C ₁ -C ₁₂ Alkoxy-substituted aryl, diphenylamino, substituted by at least one C ₁ -C ₁₂ Alkyl-substituted diphenylamino, carbazolyl, substituted by at least one C ₁ -C ₁₂ Alkyl-substituted carbazolyl;

preferably, said R ^a Each occurrence is independently deuterium, fluorine, C ₁ ～C ₁₂ Alkyl, C ₁ ～C ₁₂ Alkoxy, C ₃ -C ₁₀ Cycloalkyl, at least one C ₁ -C ₁₂ Alkyl-substituted phenyl, phenyl-C ₁ ～C ₁₂ Alkyl, at least one C ₁ -C ₁₂ Alkoxy-substituted phenyl, diphenylamino, substituted by at least one C ₁ -C ₁₂ Alkyl-substituted diphenylamino, carbazolyl, substituted by at least one C ₁ -C ₁₂ Alkyl-substituted carbazolyl;

preferably, said R ^b Each occurrence is independently deuterium, fluorine, C ₁ ～C ₁₂ Alkyl, C ₁ ～C ₁₂ Alkoxy, C ₃ -C ₁₀ Cycloalkyl, at least one C ₁ -C ₁₂ Alkyl-substituted phenyl, phenyl-C ₁ ～C ₁₂ Alkyl, at least one C ₁ -C ₁₂ Alkoxy-substituted phenyl, diphenylamino, substituted by at least one C ₁ -C ₁₂ Alkyl-substituted diphenylamino, carbazolyl, substituted by at least one C ₁ -C ₁₂ Alkyl-substituted carbazolyl;

preferably, said R ^c Each occurrence is independently deuterium, fluorine, C ₁ ～C ₁₂ Alkyl, C ₁ ～C ₁₂ Alkoxy, C ₃ -C ₁₀ Cycloalkyl, at least one C ₁ -C ₁₂ Alkyl-substituted phenyl, phenyl-C ₁ ～C ₁₂ Alkyl, at least one C ₁ -C ₁₂ Alkoxy-substituted phenyl, diphenylamino, substituted by at least one C ₁ -C ₁₂ Alkyl-substituted diphenylamino, carbazolyl, substituted by at least one C ₁ -C ₁₂ Alkyl-substituted carbazolyl.

Preferably, said R ^d Each occurrence is independently D (deuterium), fluorine, C ₁ ～C ₁₂ Alkyl, C ₁ ～C ₁₂ Alkoxy, C ₃ -C ₁₀ Cycloalkyl, at least one C ₁ -C ₁₂ Phenyl substituted by alkyl, substituted by at least one C ₁ -C ₁₂ Phenyl substituted by alkoxy, carbazolyl, substituted by at least one C ₁ -C ₁₂ Alkyl-substituted carbazolyl.

3. The boron nitride compound according to claim 1 or 2, wherein R ¹ And R is ² H, D (deuterium), fluorine, methyl, ethyl, n-propyl, isopropyl, n-butyl, tert-butyl, hexyl, octyl, decyl,

Methoxy, ethoxy, butoxy, hexyloxy, < >>

Cyclohexyl, adamantyl, phenyl, 4-methylPhenyl-phenyl, 4-ethyl-phenyl, 4-propyl-phenyl, 4-isopropylphenyl, 4-n-butylphenyl,/->

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Wherein the wavy line represents the attachment site of the group;

preferably, said R ¹ And R is ² Independently H, methyl,

Phenyl group,/->

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Wherein the wavy line represents the attachment site of the group;

preferably, said R ¹ And R is ² The same is selected from H, methyl,

Phenyl group,/->

In (a) and (b)Any one of them;

wherein R is ^g Is H, methyl, isopropyl, tert-butyl or

Preferably, R ⁴ H, C1 to C8 alkyl, C6 to C12 aryl, C5 to C18 heteroaryl, R ^f Substituted C6-C12 aryl or R ^f Substituted C5-C18 heteroaryl;

Methoxy, ethoxy, butoxy, hexyloxy, < >>

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Wherein the wavy line represents the attachment site of the group;

preferably, said R ^f Is H, methyl,

Phenyl group,/->

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Wherein the wavy line represents the attachment site of the group;

preferably, said R ⁴ Is H, methyl,

Phenyl group,/->

R ^h Is H, methyl, tert-butyl or +.>

Preferably, R ⁵ H, C1 to C8 alkyl, C6 to C18 aryl or C5 to C18 heteroaryl;

preferably, R ⁶ Is H or methyl.

4. A boron nitride compound according to any one of claims 1 to 3, wherein said boron nitride compound is any one of the following compounds:

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5. the method for producing a boron nitrogen compound according to any one of claims 1 to 4, comprising the steps of:

preferably, the molar ratio of the compound BN-Bpin to the compound B in the step (1) is 1:0.8-2;

preferably, the weakly basic material is potassium carbonate;

preferably, the catalyst in the step (1) is used in an amount of 0.1% -15% of the amount of the substance of the compound BN-Bpin;

preferably, the solvent of the reaction of step (1) is tetrahydrofuran;

preferably, the reaction of step (1) is carried out under reflux;

preferably, the reaction time of step (1) is from 5 to 24 hours;

preferably, the time of the ring closing reaction in the step (2) is 0.5-12 hours;

6. An organic electroluminescent composition, characterized in that it comprises the boron nitride compound according to any one of claims 1 to 4 and a host material as doping materials;

7. The organic electroluminescent composition according to claim 6, wherein the host material is a carbazole derivative and/or carboline derivative having a structure represented by any one of formulae (H-1) to (H-6):

wherein R is ^1H And R is ^2H Independently any of the following groups:

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wherein R is ^aH And R is ^bH H, C independently ₁ -C ₂₀ Alkyl, C ₁ -C ₂₀ Alkoxy, C ₆ -C ₂₀ Aryl, C ₁ -C ₂₀ Alkyl substituted C ₆ -C ₂₀ Aryl or C ₁ -C ₂₀ Alkoxy substituted C ₆ -C ₂₀ Aryl, number represents the attachment site of the group;

preferably, the organic electroluminescent composition preferably contains 0.3 to 30.0wt% of the boron-nitrogen compound as defined in any one of claims 1 to 4 as a doping material, and the remaining 99.7 to 70.0wt% of the composition is a host material composed of 1 to 2 compounds having the structures of formulae (H-1) to (H-6);

preferably, the host material contains 2 compounds having the structures of formulae (H-1) to (H-6) in a weight ratio of 1:5 to 5:1;

preferably, the host material in the organic electroluminescent composition is one or two of the compounds H1-1 to H1-427;

Preferably, the organic electroluminescent composition comprises 0.3-30.0wt% of boron-nitrogen compound with a structure shown in formula I as defined in any one of claims 1-4, and the rest 99.7-70.0wt% is 1 or 2 of compounds H1-1 to H1-427:

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preferably, the organic electroluminescent composition contains 2 compounds H1-1 to H1-427 as main materials, and the weight ratio of the two compounds is 1:5 to 5:1;

preferably, the doping material in the organic electroluminescent composition is any one of the boron-nitrogen compounds according to any one of claims 1 to 4; the main material is composed of any one of compounds shown as the formulas Trz1-A, trz2-A, trz3-A, trz4-A, trz5-A or Trz6-A and any one of compounds with structures shown as the formulas H-1 to H-6;

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wherein asterisks represent the attachment site of the group;

preferably, the weight ratio of the Trz1-A, trz2-A, trz3-A, trz4-A, trz5-A or Trz6-A compound to the H-1, H-2, H-3, H-4, H-5 or H-6 compound in the main material is 1:5-5:1;

Preferably, the doping material in the organic electroluminescent composition is any one of boron-nitrogen compounds with the structure shown in the formula I; the main material is composed of any one of compounds shown as formulas TRZ-1 to TRZ-76 and any one of carbazole or carboline derivatives shown as formulas H1-1 to H1-427;

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preferably, the weight ratio between the compound represented by the formulas TRZ-1 to TRZ-76 and the carbazole or carboline derivative in the host material is 1:5 to 5:1.

8. An organic electroluminescent material, characterized in that it comprises the boron-nitrogen compound according to any one of claims 1 to 4 or the organic electroluminescent composition according to claim 6 or 7.

9. An organic electroluminescent device comprising an anode and a cathode and an organic thin film layer disposed between the anode and the cathode, the organic thin film layer comprising a light emitting layer, an optional hole injection layer, an optional hole transport layer, an optional electron injection layer, wherein at least one of the light emitting layer, the electron injection layer, the electron transport layer, the hole injection layer comprises the boron-nitrogen compound of any one of claims 1-4 or the organic electroluminescent composition of claim 6 or 7;

Preferably, the light-emitting layer comprises the boron nitrogen compound according to any one of claims 1 to 4 or the organic electroluminescent composition according to claim 6 or 7;

preferably, the organic electroluminescent device further comprises an optional hole blocking layer, an optional electron blocking layer and an optional capping layer.

10. Use of an organic electroluminescent device according to claim 9 in an organic electroluminescent display or an organic electroluminescent illumination source.