Boron-containing nitrogen polyheterocyclic aromatic compound, light-emitting material, and organic electroluminescent device

Abstract

The present application relates to the technical field of organic electroluminescent material, in particular to a boron-nitrogen-containing multi-heterocyclic aromatic compound, a luminescent material and an organic electroluminescent device. The boron-nitrogen-containing multi-heterocyclic aromatic compound is selected from the compound shown in the following formula I; the boron-nitrogen-containing multi-heterocyclic aromatic compound has high stability, so that it has good rigidity, can effectively inhibit molecular vibration relaxation, reduce non-radiative transition, and prolong its service life, and at the same time, has good photoelectric conversion efficiency.

Description

Technical Field

[0001] This invention relates to the field of organic electroluminescent materials technology, and more specifically, to boron-nitrogen-containing multi-heterocyclic aromatic hydrocarbon compounds, luminescent materials, and organic electroluminescent devices. Background Technology

[0002] OLED display technology, as a self-emissive display solution, relies on organic materials to achieve electroluminescence under an electric field. Compared to traditional LCD display technology, which requires a backlight module, OLED has inherent advantages such as ultra-high contrast, fast response, flexibility, and a thinner physical structure. After decades of development, OLED has evolved from early monochrome displays to full-color displays, large sizes, and even rollable forms. Especially after the maturity of active-matrix OLED (AMOLED) driving technology, it has been widely used in high-end mobile phones, televisions, and wearable devices. However, OLED technology still faces challenges such as rapid efficiency decay of blue materials, short overall device lifespan, especially the lifespan of blue light elements, and high energy consumption under high resolution and high color purity requirements. These technical shortcomings largely stem from the low exciton utilization efficiency and poor material stability of the organic light-emitting materials themselves.

[0003] In OLED devices, the performance of the luminescent material directly determines the display effect and device lifespan. Based on the light-emitting mechanism, OLED luminescent materials have undergone three main generations of development: traditional fluorescent materials can only utilize 25% of singlet excitons, resulting in low internal quantum efficiency; second-generation phosphorescent materials (PHOLED) enhance intersystem crossing by introducing heavy metal atoms, theoretically utilizing 100% of singlet and triplet excitons, greatly improving efficiency. However, these materials typically contain precious metals such as iridium and platinum, leading to high costs, and the color purity and stability of blue phosphorescent materials remain unsatisfactory; third-generation thermally activated delayed fluorescence materials (TADF) reduce the singlet-triple energy level difference (ΔEST), allowing triplet excitons to undergo reverse intersystem crossing after thermal activation before emitting light. Theoretically, this also achieves 100% exciton utilization without the need for precious metals, reducing costs. However, conventional TADF materials typically have a broad emission spectrum, resulting in poor color purity, and in the solid state, efficiency decreases due to concentration quenching or vibrational relaxation of excited-state molecules.

[0004] In recent years, a class of multi-component heterocyclic aromatic hydrocarbon materials combining boron (B) and nitrogen (N) atoms have shown great potential as novel sensitizers or luminescent guests. These materials typically exhibit multiple resonance-thermally activated delayed fluorescence (MR-TADF) characteristics. The core of this approach lies in the precise arrangement of boron and nitrogen atoms within the aromatic framework, achieving atomic-scale separation of the highest occupied molecular orbital (HOMO) and lowest unoccupied molecular orbital (LUMO). This effectively reduces ΔEST, promotes efficient reverse intersystem crossing processes, and significantly narrows the full width at half maximum (FWHM) of the emission spectrum, thus significantly improving color purity. While these materials hold great promise for improving OLED performance, challenges remain to be overcome, including molecular design, optimization of synthesis processes, energy level matching with the host material, photothermal stability under long-term operation (especially for blue light materials), and yield control for large-scale production.

[0005] In view of this, the present invention is proposed. Summary of the Invention

[0006] The purpose of this invention is to provide boron-nitrogen-containing multi-component heterocyclic aromatic hydrocarbon compounds, luminescent materials, and organic electroluminescent devices. Embodiments of this invention provide a boron-nitrogen-containing multi-component heterocyclic aromatic hydrocarbon compound with high stability, resulting in good rigidity. This effectively suppresses molecular vibrational relaxation, reduces non-radiative transitions, and extends its lifespan. Simultaneously, it exhibits good photoelectric conversion efficiency.

[0007] This invention is implemented as follows: In a first aspect, the present invention provides a boron-nitrogen-containing polycyclic aromatic hydrocarbon compound selected from compounds shown in Formula I below; Where X is selected from the linker bond, N (R6), O, S, C (R7)(R8), Si (R9)(R 10 ), Ge(R) 11 (R) 12 Any one of Se and Te; The CY1 ring, CY2 ring, CY3 ring, and CY4 ring are each independently selected from any one of the following: substituted or unsubstituted C6-C10 aromatic rings, substituted or unsubstituted C5-C10 aromatic heterocycles, substituted or unsubstituted C6-C30 fused aromatic rings, and substituted or unsubstituted C6-C30 fused aromatic heterocycle groups, wherein the heteroatom is any one of N, O, S, Se, Si, and Ge; R1-R 12Each of the following groups is independently selected from hydrogen, deuterium, halogen, hydroxyl, cyano, nitro, amino, sulfonic acid, acyl, carbonyl, carboxylic acid, ester, isocyanate, mercapto, sulfinyl, phosphin, substituted or unsubstituted C1-C50 alkyl, substituted or unsubstituted C6-C50 aryl, substituted or unsubstituted C4-C50 heteroaryl, substituted or unsubstituted C3-C50 cycloalkyl, substituted or unsubstituted C1-C50 alkoxy, substituted or unsubstituted C2-C50 olefin and alkyne, substituted or unsubstituted C3-C50 heterocyclic, substituted or unsubstituted C5-C50 spirocyclic, substituted or unsubstituted C1-C50 silyl and substituted or unsubstituted C1-C50 germanyl, or adjacent substituents may be linked to form a ring, wherein the heteroatom may be one or more of N, O, S, P, Si, Ge, and Se.

[0008] In a second aspect, the present invention provides a luminescent material according to the foregoing embodiments, which includes the boron-nitrogen-containing polycyclic heterocyclic aromatic hydrocarbon compound described in any one of the foregoing embodiments.

[0009] Thirdly, the present invention provides an organic electroluminescent device comprising a light-emitting layer formed of the light-emitting material described in any of the foregoing embodiments.

[0010] The present invention has the following beneficial effects: The boron-nitrogen-containing multi-component heterocyclic aromatic hydrocarbon compound provided in the embodiments of the present invention is a novel sensitizing and doping material with a benzene ring as the central aromatic ring of the molecular skeleton. This structure gives the boron-nitrogen-containing multi-component heterocyclic aromatic hydrocarbon compound high stability, which can suppress molecular vibrational relaxation and reduce non-radiative transitions, thereby achieving a better lifespan. At the same time, the boron-nitrogen-containing multi-component heterocyclic aromatic hydrocarbon compound has good high exciton utilization and small ΔEST, which can more easily realize intersystem crossing and achieve better photoelectric conversion efficiency. Attached Figure Description

[0011] To more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings used in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of the present invention and should not be regarded as a limitation on the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.

[0012] Figure 1 The 1H NMR spectrum of boron-nitrogen-containing multi-heterocyclic aromatic hydrocarbon compound I-83 provided in Example 1 of this invention. Detailed Implementation

[0013] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below. Where specific conditions are not specified in the embodiments, conventional conditions or conditions recommended by the manufacturer shall apply. Reagents or instruments whose manufacturers are not specified are all conventional products that can be purchased commercially.

[0014] In a first aspect, embodiments of the present invention provide a boron-nitrogen-containing multi-heterocyclic aromatic hydrocarbon compound, which is selected from compounds shown in Formula I below; Where X is selected from the linker bond, N (R6), O, S, C (R7)(R8), Si (R9)(R 10 ), Ge(R) 11 (R) 12 Any one of Se and Te; The CY1 ring, CY2 ring, CY3 ring, and CY4 ring are each independently selected from any one of the following: substituted or unsubstituted C6-C10 aromatic rings, substituted or unsubstituted C5-C10 aromatic heterocycles, substituted or unsubstituted C6-C30 fused aromatic rings, and substituted or unsubstituted C6-C30 fused aromatic heterocycle groups, wherein the heteroatom is any one of N, O, S, Se, Si, and Ge; R1-R 12 Each of the following groups is independently selected from hydrogen, deuterium, halogen, hydroxyl, cyano, nitro, amino, sulfonic acid, acyl, carbonyl, carboxylic acid, ester, isocyanate, mercapto, sulfinyl, phosphin, substituted or unsubstituted C1-C50 alkyl, substituted or unsubstituted C6-C50 aryl, substituted or unsubstituted C4-C50 heteroaryl, substituted or unsubstituted C3-C50 cycloalkyl, substituted or unsubstituted C1-C50 alkoxy, substituted or unsubstituted C2-C50 olefin and alkyne, substituted or unsubstituted C3-C50 heterocyclic, substituted or unsubstituted C5-C50 spirocyclic, substituted or unsubstituted C1-C50 silyl and substituted or unsubstituted C1-C50 germanyl, or adjacent substituents may be linked to form a ring, wherein the heteroatom may be one or more of N, O, S, P, Si, Ge, and Se.

[0015] The central component of this boron-nitrogen-containing multi-membered heterocyclic aromatic hydrocarbon compound is a six-membered heterocyclic structure containing a benzene ring and boron and nitrogen. This structure exhibits good rigidity, effectively suppressing molecular vibrational relaxation, reducing non-radiative transitions, and extending its lifetime. Simultaneously, this boron-nitrogen-containing multi-membered heterocyclic aromatic hydrocarbon compound possesses good exciton utilization and a small energy range, making it easier to achieve intersystem crossing and thus better luminescence.

[0016] Furthermore, in the embodiments of the present invention, R1-R 12The substituted or unsubstituted C1-C50 alkyl group is selected from substituted or unsubstituted C1-C10 alkyl groups; for example, any one of methyl, ethyl, isopropyl, tert-butyl, 2-methylpropyl and 2,2-dimethylpropyl.

[0017] R1-R 12 The substituted or unsubstituted C6-C50 aryl group is selected from substituted or unsubstituted C6-C12 aryl groups; for example, any one of phenyl, isopropylphenyl, tert-butylbenzene and 2,2-dimethylindenyl.

[0018] R1-R 12 The substituted or unsubstituted C4-C50 heteroaryl group is selected from the substituted or unsubstituted C4-C15 heteroaryl group; for example, it is any one of benzothiophene, benzofuran, carbazole, fluorene, thioxanthene, oxanthracene, benzoselenophene and diphenylamino.

[0019] R1-R 12 The substituted or unsubstituted C3-C50 cycloalkyl group is selected from substituted or unsubstituted C3-C10 cycloalkyl groups; for example, cyclopentyl or cyclohexyl.

[0020] R1-R 12 The substituted or unsubstituted C1-C50 silane is selected from the substituted or unsubstituted C1-C10 silane; for example, trimethylsilyl or triphenylsilyl.

[0021] R1-R 12 The substituted or unsubstituted C1-C50 germanyl group is selected from the substituted or unsubstituted C1-C10 germanyl groups, such as trimethylgermanyl or triphenylgermanyl.

[0022] In the embodiments of the present invention, the CY1 ring, CY2 ring, CY3 ring and CY4 ring are independently selected from any one of the following: benzene ring, naphthyl ring, phenanthrene ring, furan, thiophene, pyrrole, pyridine, pyrimidine, 9,9-dimethylfluorenyl, 9,9-diphenylfluorenyl, dibenzofuran, dibenzothiophene, dibenzoselenene, spirofluorenyl, benzofuran, benzothiophene, benzoquinoline and 5,5-dimethylbenzo[b] [1]siloxane[b][ ...

[0023] Furthermore, in the embodiments of the present invention, "substituted or unsubstituted" means that one, two or more hydrogen atoms on the carbon atom are substituted by one, two or more of the following substituents: deuterium, halogen, nitrile, C1-C20 alkyl, C3-C20 cycloalkyl, C6-C20 aryl, C6-C20 heteroaryl, C3-C20 heterocyclic, C3-C20 silyl, C3-C20 germanyl, or substituted by a substituent formed by the fusion of two or more of the substituents shown above. The heteroatom can be one or more combinations of O, S, N, P, B, Si and Ge.

[0024] Furthermore, in the embodiments of the present invention, the boron-nitrogen-containing polycyclic heterocyclic aromatic hydrocarbon compound is selected from any one of the compounds shown in the following structural formulas:

[0025]

[0026]

[0027]

[0028]

[0029]

[0030]

[0031]

[0032]

[0033]

[0034]

[0035]

[0036]

[0037]

[0038]

[0039]

[0040]

[0041]

[0042]

[0043]

[0044]

[0045]

[0046]

[0047]

[0048]

[0049]

[0050]

[0051]

[0052]

[0053]

[0054]

[0055] .

[0056] Secondly, embodiments of the present invention provide a method for preparing boron-nitrogen-containing polycyclic heterocyclic aromatic hydrocarbon compounds, comprising synthesis according to the following synthetic route: .

[0057] The specific process is as follows: Reactant 1, nitrogen heterocyclic reactant 1, palladium catalyst (e.g., including but not limited to tris(dibenzylacetone)palladium (DBA palladium)), organophosphorus (e.g., including but not limited to tri-tert-butylphosphine (t-Bu3P)), and base (e.g., including but not limited to cesium carbonate (Cs2CO3)) are mixed and reacted to form intermediate 1. The molar ratio of the base to reactant 1 is (1.5-2.5):1; the molar ratio of the palladium catalyst to reactant 1 is 1:(15-25); the molar ratio of the organophosphorus catalyst to reactant 1 is 1:(15-25); the molar ratio of the nitrogen heterocyclic reactant 1 to reactant 1 is 1:(2-3); and the reaction temperature is 120-150°C.

[0058] For example, the specific steps are as follows: Add reactant 1, nitrogen heterocyclic reactant 1, cesium carbonate (Cs2CO3), and o-xylene solvent to a three-necked flask. After replacing the nitrogen gas, add tris(dibenzylacetone)dipalladium (DBA palladium) and tri-tert-butylphosphine (t-Bu3P). Then react at 130°C for 12 h. After the reaction is completed, separate intermediate 1 by liquid-liquid chromatography and column chromatography. The molar ratio of cesium carbonate (Cs2CO3) to reactant 1 is 2:1, the molar ratio of DBA palladium to reactant 1 is 1:20, and the molar ratio of t-Bu3P to reactant 1 is 1:20.

[0059] Intermediate 1, nitrogen heterocyclic reactant 2, palladium catalyst (e.g., including but not limited to tris(dibenzylacetone)palladium (DBA palladium)), organophosphorus (e.g., including but not limited to tri-tert-butylphosphine (t-Bu3P)), and base (e.g., including but not limited to cesium carbonate (Cs2CO3)) are mixed and reacted to form intermediate 2; wherein, the molar ratio of the base to intermediate 1 is (1.5-2.5):1, the molar ratio of the palladium catalyst to intermediate 1 is 1:(15-25), the molar ratio of the organophosphorus to intermediate 1 is 1:(15-25), the molar ratio of the nitrogen heterocyclic reactant 2 to intermediate 1 is 1:(1.1~1.5), and the reaction temperature is 120-150℃.

[0060] For example, the specific steps are as follows: Add reactant intermediate 1, nitrogen heterocyclic reactant 2, cesium carbonate (Cs2CO3), and solvent o-xylene to a three-necked flask, replace with nitrogen, add DBA palladium and t-Bu3P, and then react at 130℃ for 12 h. After the reaction is completed, intermediate 2 is obtained by separation by liquid-liquid chromatography and column chromatography. The molar ratio of cesium carbonate (Cs2CO3) to intermediate 1 is 2:1, the molar ratio of DBA palladium to intermediate 1 is 1:20, and the molar ratio of t-Bu3P to intermediate 1 is 1:20.

[0061] The intermediate 2, an organolithium reagent (e.g., tert-butyllithium (tBuLi)), and a boride (e.g., boron tribromide (BBr3)) are mixed and reacted. The molar ratio of the organolithium reagent to the intermediate 2 is (1.5-2.5):1, and the molar ratio of the boride to the intermediate 2 is (1.5-2.5):1; the reaction temperature is 120-150℃.

[0062] For example, the specific steps are as follows: Intermediate 2 and tert-butylbenzene are added to a three-necked flask, nitrogen is purged, and the flask is cooled to -78°C. Then, under a nitrogen atmosphere, a tert-butyllithium (tBuLi) solution is slowly added dropwise to the three-necked flask. After reacting for 0.5 h, the flask is heated to 60°C and stirred for 2 h. The n-pentane is removed under vacuum. Boron tribromide (BBr3) is then added at 30°C, and the reaction system is stirred at room temperature for 1 h. Finally, N,N-diisopropylethylamine (DIEA) is added at 0°C, and the reaction system is stirred at 130°C for 6 h, then cooled to room temperature. Finally, residual boron tribromide (BBr3) is quenched with methanol, separated, column chromatography, and vacuum gradient sublimation to obtain Formula I. The molar ratio of tBuLi to intermediate 2 is 2:1, the molar ratio of BBr3 to intermediate 2 is 2:1, and the molar ratio of DIEA to intermediate 2 is 2:1.

[0063] The preparation method provided in the embodiments of the present invention can adopt the following specific synthetic route: .

[0064] Thirdly, embodiments of the present invention provide an organic electroluminescent device comprising a light-emitting layer formed of the boron-nitrogen-containing polycyclic heterocyclic aromatic hydrocarbon compound.

[0065] Specifically, the organic electroluminescent device includes an anode and a cathode, and an organic functional layer disposed between the anode and the cathode. The organic functional layer includes a hole transport layer, a light-emitting layer, and an electron transport layer. The raw materials forming the light-emitting layer include a host material and a dopant material. The dopant material includes boron-nitrogen-containing polycyclic heterocyclic aromatic hydrocarbon compounds as described above.

[0066] Anode materials can be divided into two main categories. The first category consists of traditional anode materials, such as indium tin oxide (ITO), indium zinc oxide (IZO), gold (Au), and silver (Ag). The second category consists of novel anode materials, such as poly(3,4-ethylenedioxythiophene):polystyrene sulfonic acid (PEDOT:PSS), polyaniline (PANI), and graphene composite electrodes.

[0067] The hole transport layer material that forms the hole transport layer can be a phthalocyanine derivative, a conductive polymer, or a polymer containing conductive dopants such as polyphenylene ethylene, polyaniline / dodecylbenzenesulfonic acid, poly(3,4-ethylenedioxythiophene) / poly(4-styrenesulfonate), polyaniline / camphor sulfonic acid, polyaniline / poly(4-styrenesulfonate), aromatic amine derivatives, etc.

[0068] Furthermore, a hole injection layer and an electron blocking layer may also be incorporated into the hole transport layer. The hole injection layer is located between the anode and the hole transport layer, and the material used can be a modified PEDOT:PSS, formula A, or formula B; however, it is not limited to these.

[0069]

[0070] Furthermore, the raw materials forming the light-emitting layer generally include a host material and a dopant material. The host material provides a carrier transport channel, and the dopant material is used for efficient and high-color-purity light emission. The dopant material can be further divided into a first dopant material and a second dopant material. The first dopant material is generally a red, green, or blue light-emitting material, and the second dopant material is a sensitizing material. The sensitizing material is responsible for exciton generation and energy transfer. In the embodiments of the present invention, the boron-nitrogen-containing polycyclic heterocyclic aromatic hydrocarbon compound shown in Formula I can be used as the first dopant material or as the second dopant material.

[0071] Furthermore, the electron transport layer is generally a single-layer structure, and the material forming the electron transport layer can be a single compound or a combination of multiple compounds, such as Alq3 (tris(8-hydroxyquinoline)aluminum), Znq (tris(8-hydroxyquinoline)zinc), Bebq2 (bis(10-hydroxybenzo[h]quinoline)beryllium, TPBi (1,3,5-tris(1-phenyl-1H-benzimidazol-2-yl)benzene), Bphen (4,7-diphenyl-1,10-phenanthroline), TAZ (1,2,4-triazole derivative), or polyfluorene derivatives and poly(p-styrene).

[0072] Furthermore, an electron injection layer and a hole blocking layer may also be incorporated into the electron transport layer. The electron injection layer is located between the electron transport layer and the cathode, and the material forming the electron injection layer can be one or more of LiF, NaCl, CsF, Li2O, Cs2CO3, BaO, Na, Li, and Ca.

[0073] Furthermore, the cathode material forming the cathode includes metals or alloys such as magnesium (Mg), silver (Ag), aluminum (Al), aluminum-lithium (Al-Li), calcium (Ca), magnesium-indium (Mg-In), and magnesium-silver (Mg-Ag), as well as any combination thereof.

[0074] The features and performance of the present invention will be further described in detail below with reference to embodiments.

[0075] Example 1 This invention provides a method for preparing boron-nitrogen-containing polycyclic heterocyclic aromatic hydrocarbon compound I-83, comprising: 1. Synthesis of nitrogen heterocyclic reactant 1-1

[0076] 9,9-Dimethyl-3-bromofluorene (1 eq), 4-tert-butyl-2-chloroaniline (1.2 eq), and xylene were added to a three-necked flask. After purging with nitrogen, DBA palladium (0.6% eq), X-phos (1.2% eq), and sodium tert-butoxide (2.0 eq) were added. After purging with nitrogen again, the mixture was heated to reflux for 24 h. After the reaction was complete, the mixture was cooled to room temperature, quenched with ice water, stirred for 1 h, and then separated. The organic phase was evaporated to dryness, and recrystallized with dichloromethane and n-hexane to give nitrogen-containing heterocyclic reactant 1-1 (yield 71.3%). Mass spectrometry reading: 340.17.

[0077] 2. Synthesis of intermediate 2-1

[0078] Reactant 1-1 (1 eq), along with nitrogen-containing heterocyclic reactant 1-1 (2.2 eq), Cs₂CO₃ (2 eq), and o-xylene solvent, were added to a three-necked flask. After purging with nitrogen, DBA palladium (0.05 eq) and t-Bu₃P (0.05 eq) were added, followed by another purging with nitrogen. The mixture was reacted at 130 °C for 12 h. After the reaction was complete, intermediate 2-1 (yield 73.3%) was obtained by separation by liquid-liquid chromatography and column chromatography (developing solvent: dichloromethane and hexane). Mass spectrometry reading: 888.93.

[0079] 3. Synthesis of I-83

[0080] Intermediate 2-1 (1 eq) and tert-butylbenzene were added to a three-necked flask, purged with nitrogen, and cooled to -78°C. Then, under a nitrogen atmosphere, a solution of tert-butyllithium (tBuLi) (2 eq) was slowly added dropwise to the three-necked flask. After reacting for 0.5 h, the mixture was heated to 60°C and stirred for 2 h. The n-pentane was removed under vacuum. Then, BBr3 (2 eq) was added at -30°C, and the reaction system was stirred at room temperature for 1 h. Finally, DIEA (2 eq) was added at 0°C, and the reaction system was stirred at 130°C for 6 h and then cooled to room temperature. Finally, residual boron tribromide (BBr3) was quenched with methanol, separated, column chromatography (evolving solvent: dichloromethane and hexane), and vacuum gradient sublimation were used to obtain Formula I-83 (yield 29.6%).

[0081] Characterization data: Mass spectrometry test value: 817.25.

[0082] Elemental analysis theoretical data: C: 88.21, H: 7.03, B: 1.32, N: 3.43; Test values: C: 87.52, H: 7.46, B: 1.18, N: 3.84.

[0083] The proton NMR spectrum of Formula I-83 is as follows: Figure 1 As shown.

[0084] The preparation methods of other boron-nitrogen-containing polycyclic heterocyclic aromatic hydrocarbon compounds provided in the embodiments of the present invention are the same as those provided in Example 1, and will not be described in detail here.

[0085] Device Example 1 Organic electroluminescent devices were prepared using boron-nitrogen-containing multi-component heterocyclic aromatic hydrocarbon compounds of formula I-83 provided in Example 1. The preparation method is as follows: 1. On the anode, the ITO patterned glass substrate is cut into a size of 50mm×50mm×0.5mm, cleaned three times with detergent for 5 minutes each time, then ultrasonically treated with isopropanol and acetone for 10 minutes in sequence, dried with nitrogen, and finally exposed to ultraviolet light and ozone for 30 minutes.

[0086] 2. The obtained glass substrate is loaded onto a vacuum deposition equipment. First, Formula A is deposited on the anode as a hole injection layer with a deposition thickness of 100 angstroms. Then, Formula C is deposited with a hole layer thickness of 600 angstroms. Finally, Formula D is deposited with an electron blocking layer thickness of 50 nm.

[0087]

[0088] 3. Prepare a light-emitting layer with a thickness of 400 Å by evaporating the host material 4,4'-bis(N-carbazolyl)1,1'-biphenyl (CBP) and the dopant material formula I-83 at a mass ratio of 95:5. Then, evaporate a TPBI (formula E) electron transport layer with a thickness of 400 Å on the light-emitting layer, evaporate a LiF electron injection layer with a thickness of 10 Å on the electron transport layer, and finally evaporate a cathode material Al with a thickness of 1500 Å on the electron injection layer to obtain a green-emitting organic electroluminescent device.

[0089] Device Example 2 An organic electroluminescent device was prepared according to the preparation method of Device Example 1. The preparation method is as follows: Steps 1 and 2 are the same as in Device Example 1.

[0090] 3. Prepare a light-emitting layer with a thickness of 400 Å by evaporating the host material 4,4'-bis(N-carbazolyl)1,1'-biphenyl (CBP) and the first green light dopant GD-1 at a mass ratio of 95:5. Then, evaporate a TPBI (Formula E) electron transport layer with a thickness of 400 Å on the light-emitting layer, evaporate a LiF electron injection layer with a thickness of 10 Å on the electron transport layer, and finally evaporate a cathode material Al with a thickness of 1500 Å on the electron injection layer to obtain a green light-emitting organic electroluminescent device.

[0091] Device Example 3 An organic electroluminescent device was prepared according to the preparation method of Device Example 1. The preparation method is as follows: Steps 1 and 2 are the same as in Device Example 1.

[0092] 3. Prepare a light-emitting layer with a thickness of 400 Å by evaporating the host material 4,4'-bis(N-carbazolyl)1,1'-biphenyl (CBP), the first green light dopant GD-1, and the second dopant I-83 at a mass ratio of 95:4:1. Then, evaporate a TPBI (Formula E) electron transport layer with a thickness of 400 Å on the light-emitting layer, evaporate a LiF electron injection layer with a thickness of 10 Å on the electron transport layer, and finally evaporate a cathode material Al with a thickness of 1500 Å on the electron injection layer to obtain a green light-emitting organic electroluminescent device.

[0093]

[0094] Device Examples 4-53 Organic electroluminescent devices were prepared according to the preparation method of Device Example 1. The boron-nitrogen polycyclic heterocyclic aromatic hydrocarbon compound of formula I-83 in the organic electroluminescent device was replaced with boron-nitrogen polycyclic heterocyclic aromatic hydrocarbon compounds of formulas I-1, I-9, I-14, I-20, I-50, I-85, I-104, I-125, I-141, I-153, I-182, I-200, I-213, I-227, I-245, I-280, I-328, I-384, I-403, I-418, I-436, I-491, I-513, I-535 and I-550, respectively. Organic electroluminescent devices were prepared from these compounds and are referred to as Device Example 4 to Device Example 28. See Table 1 for details.

[0095] Referring to Device Example 3, the boron-nitrogen-containing multi-component heterocyclic aromatic hydrocarbon compound of formula I-83 in the organic electroluminescent device was replaced with boron-nitrogen-containing multi-component heterocyclic aromatic hydrocarbon compounds of formulas I-1, I-9, I-14, I-20, I-50, I-85, I-104, I-125, I-141, I-153, I-182, I-200, I-213, I-227, I-245, I-280, I-328, I-384, I-403, I-418, I-436, I-491, I-513, I-535 and I-550, and organic electroluminescent devices were prepared accordingly, referred to as Device Example 29 to Device Example 53, as detailed in Table 2.

[0096] Organic electroluminescent devices were prepared using the same method as in Device Example 1, except that the doping material I-83 in the light-emitting layer was replaced with compound 1, compound 2, compound 3, compound 4, compound 5, compound 6, compound 7, compound 8, compound 9, compound 10, compound 11, and compound 12, and these were respectively prepared into organic electroluminescent devices, referred to as Comparative Examples 1-12. The structures of the compounds are shown below.

[0097] Organic electroluminescent devices were prepared using the same method as in Device Example 3, except that the second dopant material of Formula I-83 in the light-emitting layer was replaced with compound 1, compound 2, compound 3, compound 4, compound 5, compound 6, compound 7, compound 8, compound 9, compound 10, compound 11, and compound 12, and these were respectively prepared into organic electroluminescent devices, referred to as Comparative Examples 13-24. The structures of the compounds are shown below.

[0098]

[0099] The luminescence characteristics of the organic electroluminescent devices prepared in Device Examples 1-53 and the devices obtained in Comparative Examples 1-24 were tested. The measurements were performed using a KEITHLEY2400 source measurement unit and a CS-2000 spectroradiometer to evaluate the driving voltage, luminous efficiency and lifetime. The results are shown in Tables 1 and 2.

[0100] Table 1. Luminescence detection data of organic electroluminescent devices

[0101] Table 2. Luminescence detection data of organic electroluminescent devices

[0102] As shown in Table 1, compared with Comparative Examples 1-12, the device lifetime of the boron-nitrogen-containing multi-heterocyclic aromatic hydrocarbon compound provided by the present invention in the single-doped system device is 17%~19% longer than that of Comparative Examples 1-12, and the driving voltage and efficiency are reduced by 4.2%~7.9% and increased by 8.9%~16.4% respectively compared with the comparative examples.

[0103] As shown in Table 2, compared with Device 2 and Comparative Examples 13-24, when the boron-nitrogen-containing multi-heterocyclic aromatic hydrocarbon compound provided by the present invention is used as the second doping material, the device efficiency and device driving voltage are increased by 23.0%~32.3% and decreased by 7.4%~9.9% respectively compared with OLED devices made of known materials. Moreover, in the dual-doped device, the device lifetime is also significantly improved compared with the single-doped device, by 25%~27%.

[0104] In summary, organic electroluminescent devices prepared using boron-nitrogen-containing multi-cyclic aromatic hydrocarbon compounds provided by this invention as doping materials for the light-emitting layer have relatively low driving voltage, good luminous efficiency, and longer service life.

[0105] The above description is merely a preferred embodiment of the present invention and is not intended to limit the invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A boron-nitrogen-containing polycyclic heterocyclic aromatic hydrocarbon compound, characterized in that, It is selected from the compounds shown in Formula I below; Where X is selected from the linker bond, N (R6), O, S, C (R7)(R8), Si (R9)(R 10 ), Ge(R) 11 (R) 12 Any one of Se and Te; The CY1 ring, CY2 ring, CY3 ring, and CY4 ring are each independently selected from any one of the following: substituted or unsubstituted C6-C10 aromatic rings, substituted or unsubstituted C5-C10 aromatic heterocycles, substituted or unsubstituted C6-C30 fused aromatic rings, and substituted or unsubstituted C6-C30 fused aromatic heterocycle groups, wherein the heteroatom is any one of N, O, S, Se, Si, and Ge; R1-R 12 Each of the following groups is independently selected from hydrogen, deuterium, halogen, hydroxyl, cyano, nitro, amino, sulfonic acid, acyl, carbonyl, carboxylic acid, ester, isocyanate, mercapto, sulfinyl, phosphin, substituted or unsubstituted C1-C50 alkyl, substituted or unsubstituted C6-C50 aryl, substituted or unsubstituted C4-C50 heteroaryl, substituted or unsubstituted C3-C50 cycloalkyl, substituted or unsubstituted C1-C50 alkoxy, substituted or unsubstituted C2-C50 olefin and alkyne, substituted or unsubstituted C3-C50 heterocyclic, substituted or unsubstituted C5-C50 spirocyclic, substituted or unsubstituted C1-C50 silyl and substituted or unsubstituted C1-C50 germanyl, or adjacent substituents are linked to form a ring, wherein the heteroatom is one or more of N, O, S, P, Si, Ge, and Se.

2. The boron-nitrogen-containing polycyclic heterocyclic aromatic hydrocarbon compound according to claim 1, characterized in that, R1-R 12 The groups in it satisfy at least one of the following requirements: (1) The substituted or unsubstituted C1-C50 alkyl group is selected from the substituted or unsubstituted C1-C10 alkyl group; (2) The substituted or unsubstituted C6-C50 aryl group is selected from the substituted or unsubstituted C6-C12 aryl group; (3) The substituted or unsubstituted C4-C50 heteroaryl group is selected from the substituted or unsubstituted C4-C15 heteroaryl group; (4) The substituted or unsubstituted C3-C50 cycloalkyl group is selected from the substituted or unsubstituted C3-C10 cycloalkyl group; (5) The substituted or unsubstituted C1-C50 silane is selected from the substituted or unsubstituted C1-C10 silane; (6) The substituted or unsubstituted C1-C50 germanium alkyl group is selected from the substituted or unsubstituted C1-C10 germanium alkyl group.

3. The boron-nitrogen-containing polycyclic heterocyclic aromatic hydrocarbon compound according to claim 1 or 2, characterized in that, R1-R 12 The groups in it satisfy at least one of the following requirements: (1) The substituted or unsubstituted C1-C50 alkyl group is selected from any one of methyl, ethyl, isopropyl, tert-butyl, 2-methylpropyl and 2,2-dimethylpropyl; (2) The substituted or unsubstituted C6-C50 aryl group is selected from any one of phenyl, isopropylphenyl, tert-butylbenzene and 2,2-dimethylindenyl; (3) The substituted or unsubstituted C4-C50 heteroaryl group is selected from any one of benzothiophene, benzofuran, carbazole, fluorene, thioxanthene, oxanthracene, benzoselenophene and diphenylamino. (4) The substituted or unsubstituted C3-C50 cycloalkyl group is selected from cyclopentyl or cyclohexyl; (5) The substituted or unsubstituted C1-C50 silane is selected from trimethylsilyl or triphenylsilyl; (6) The substituted or unsubstituted C1-C50 germanyl group is selected from trimethylgermanyl or triphenylgermanyl.

4. The boron-nitrogen-containing polycyclic heterocyclic aromatic hydrocarbon compound according to claim 1, characterized in that, The CY1 ring, CY2 ring, CY3 ring and CY4 ring are each independently selected from any one of the following: benzene ring, naphthyl ring, phenanthrene ring, furan, thiophene, pyrrole, pyridine, pyrimidine, 9,9-dimethylfluorenyl, 9,9-diphenylfluorenyl, dibenzofuran, dibenzothiophene, dibenzoselenene, spirofluorenyl, benzofuran, benzothiophene, benzoquinoline and 5,5-dimethylbenzo[b] [1]siloxane[b][1] silyrocyclopentadiene[b][b][1][b ...

5. The boron-nitrogen-containing polycyclic heterocyclic aromatic hydrocarbon compound according to claim 1, characterized in that, The substitution in substituted or unsubstituted form is that the hydrogen on the carbon is substituted by one, two or more of the following substituents: deuterium, halogen, nitrile, C1-C20 alkyl, C3-C20 cycloalkyl, C6-C20 aryl, C6-C20 heteroaryl, C3-C20 heterocyclic, C3-C20 silyl, C3-C20 germanyl, or substituted by a substituent formed by the fusion of two or more of the substituents shown above, wherein the heteroatom is one or a combination of O, S, N, P, B, Si and Ge.

6. The boron-nitrogen-containing polycyclic heterocyclic aromatic hydrocarbon compound according to claim 1, characterized in that, The boron-nitrogen-containing polycyclic heterocyclic aromatic hydrocarbon compound is selected from any one of the compounds shown in the following structural formulas: 。 7. A luminescent material, characterized in that, It includes the boron-nitrogen-containing polycyclic aromatic hydrocarbon compounds as described in any one of claims 1-6.

8. The luminescent material according to claim 7, characterized in that, It includes a host material and a dopant material, wherein the dopant material is the boron-nitrogen-containing polycyclic heterocyclic aromatic hydrocarbon compound.

9. An organic electroluminescent device, characterized in that, It includes a light-emitting layer formed from the light-emitting material as described in claim 7 or 8.

10. The organic electroluminescent device according to claim 9, characterized in that, It includes an anode, a hole injection layer, a hole transport layer, an electron blocking layer, a light-emitting layer, an electron transport layer, an electron injection layer, and a cathode arranged in sequence.

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