Fused heterocyclic compound and organic electroluminescent device containing same

Abstract

The invention relates to the technical field of organic electroluminescence, in particular to a fused heterocyclic compound and an organic electroluminescence device containing the compound. The compound has a characteristic double-boron-nitrogen aromatic fused structure, and rigid substituents such as phenanthrene amine, naphthylamine, anthramine and fluoranthene amine are introduced to the periphery of the compound, so that a molecule has a relatively high T2 energy level, the T1 energy level is remarkably reduced, T2 is slightly higher than S1 energy level, T2-T1 internal conversion is inhibited, T2-S1 exciton up-conversion is promoted, the exciton utilization rate is increased, and the luminous efficiency is remarkably improved. An OLED device prepared from the compound has the advantages of low starting voltage, high color purity, high efficiency and excellent service life, meets the requirements of a high-performance display panel on a luminescent material, and has a good application prospect.

Description

Technical Field

[0001] This invention relates to the field of organic electroluminescence technology, and particularly to a fused heterocyclic compound and an organic electroluminescence device containing the compound. Background Technology

[0002] Organic light-emitting devices (OLEDs) are current-driven thin-film devices with a sandwich-like structure, consisting of one or more layers of organic functional materials sandwiched between the anode and cathode. Under the influence of an electric field, holes generated at the anode and electrons at the cathode move and are injected into the hole transport layer and electron transport layer, respectively, migrating to the light-emitting layer. When these two electrons recombine in the light-emitting layer, they generate excitons, which in turn excite the light-emitting molecules to ultimately produce visible light.

[0003] OLED features self-emissive properties, wide viewing angle, wide color gamut, and short response time. It can be made into large-size and / or flexible ultra-thin panels. It is a rapidly developing new display technology with a high degree of process integration. It is currently widely used in display products such as TVs, smartphones, tablets, automotive displays, and lighting. It will also be further applied to creative display products such as large-size displays and flexible screens.

[0004] In OLED devices, the emissive layer material, especially the guest material doped in the emissive layer, plays a crucial role in luminous efficiency, device lifetime, and emission spectrum. In recent years, multiple resonance thermally induced delayed fluorescence (MR-TADF) materials have attracted widespread attention from the scientific and industrial communities due to their advantages of high color purity and high luminous efficiency (Adv. Mater. 2016, 28, 2777–2781). Summary of the Invention

[0005] As mentioned above, MR-TADF materials have attracted widespread attention from the scientific and industrial communities due to their high color purity and high luminous efficiency. However, the lifespan of MR-TADF materials remains a key factor affecting the lifespan of OLED panels. Therefore, obtaining MR-TADF luminescent molecules that combine long lifespan with high color purity and high luminous efficiency is crucial for expanding their further applications in the display field.

[0006] To address the aforementioned problems, one objective of this invention is to provide a novel fused heterocyclic compound. Specifically, this application provides: 1) a fused heterocyclic compound, wherein the compound is represented by the general formula D1, D2, or D3:

[0007]

[0008] X1 is represented by the following general formulas E1, E2, E3, and E4:

[0009]

[0010] R1~R 17 The groups are independently selected from hydrogen atoms, deuterium atoms, fluorine atoms, substituted silyl groups with 1 to 50 carbon atoms, substituted or unsubstituted alkyl groups with 1 to 50 carbon atoms, substituted or unsubstituted alkenyl groups with 2 to 20 carbon atoms, substituted or unsubstituted alkynyl groups with 2 to 20 carbon atoms, substituted or unsubstituted alkoxy groups with 1 to 50 carbon atoms, substituted or unsubstituted fluoroalkyl groups with 1 to 20 carbon atoms, substituted or unsubstituted fluoroalkoxy groups with 1 to 20 carbon atoms, substituted or unsubstituted cycloalkyl groups with 3 to 50 cyclic carbon atoms, substituted or unsubstituted aryl groups with 6 to 50 cyclic carbon atoms, and substituted or unsubstituted monovalent heterocyclic groups with 5 to 50 cyclic carbon atoms.

[0011] Y1 is either O or S.

[0012] 2) According to the fused heterocyclic compound described in 1) above, wherein R1 to R 17The substituents are independently selected from: hydrogen atom, deuterium atom, chlorine atom, bromine atom, fluorine atom, cyano, nitro, substituted silyl group, substituted or unsubstituted methyl, substituted or unsubstituted ethyl, substituted or unsubstituted n-propyl, substituted or unsubstituted isopropyl, substituted or unsubstituted n-butyl, substituted or unsubstituted isobutyl, substituted or unsubstituted sec-butyl, substituted or unsubstituted tert-butyl, substituted or unsubstituted 2-methylbutyl, substituted or unsubstituted n-pentyl, substituted or unsubstituted sec-pentyl, substituted or unsubstituted trifluoromethyl, etc. Substituted or unsubstituted pentafluoroethyl, substituted or unsubstituted 2,2,2-trifluoroethyl, substituted or unsubstituted vinyl, substituted or unsubstituted propenyl, substituted or unsubstituted n-butenyl, substituted or unsubstituted isobutenyl, substituted or unsubstituted n-pentenyl, substituted or unsubstituted isopentenyl, substituted or unsubstituted neopentenyl, substituted or unsubstituted ethynyl, substituted or unsubstituted propynyl, substituted or unsubstituted n-butynyl, substituted or unsubstituted isobutynyl, substituted or unsubstituted n-pentynyl, substituted or unsubstituted isopentenynyl Substituted or unsubstituted neopentynyl, substituted or unsubstituted cyclopropyl, substituted or unsubstituted cyclobutyl, substituted or unsubstituted cyclopentyl, substituted or unsubstituted cyclohexyl, substituted or unsubstituted adamantyl, substituted or unsubstituted thiophene, substituted or unsubstituted indolyl, substituted or unsubstituted furanyl, substituted or unsubstituted phenyl, substituted or unsubstituted pyridyl, substituted or unsubstituted biphenyl, substituted or unsubstituted naphthyl, substituted or unsubstituted anthraceneyl, substituted or unsubstituted phenanthryl, substituted or unsubstituted indenyl, substituted or unsubstituted Substituted fluorenyl, substituted or unsubstituted spirodifluorenyl, substituted or unsubstituted indofluorenyl, substituted or unsubstituted fluoranyl, substituted or unsubstituted pyrene, substituted or unsubstituted peryl, substituted or unsubstituted tetraphenyl, substituted or unsubstituted benzothiophene, substituted or unsubstituted benzothiophene, substituted or unsubstituted benzofuranyl, substituted or unsubstituted dibenzothiophene, substituted or unsubstituted dibenzothiophene, substituted or unsubstituted dibenzofuranyl, substituted or unsubstituted dibenzoselenyl, and substituted or unsubstituted carbazoyl.

[0013] 3) According to the fused heterocyclic compounds described in 1) or 2) above, wherein "substituted or unsubstituted" in the fused heterocyclic compounds means that the substituent is independently selected from deuterium, tritium, halogen, cyano, nitro, hydroxyl, monovalent alkyl or cycloalkyl with 1 to 10 carbon atoms, monovalent monocyclic aryl or fused cyclic aryl with 6 to 30 carbon atoms, or monovalent heterocyclic group or fused cyclic heteroaryl with 2 to 50 carbon atoms.

[0014] 4) A fused heterocyclic compound according to any one of 1) to 3) above, wherein the fused heterocyclic compound is selected from the following structures:

[0015]

[0016]

[0017]

[0018]

[0019]

[0020]

[0021]

[0022]

[0023]

[0024]

[0025]

[0026]

[0027]

[0028]

[0029]

[0030]

[0031]

[0032]

[0033]

[0034]

[0035] 5) An organic electroluminescent device, wherein the organic electroluminescent device comprises an anode, a cathode, and at least one organic thin film located between the anode and the cathode, the organic thin film containing any one of the compounds described in 1) to 4).

[0036] 6) The organic electroluminescent device according to 5) above, wherein the organic thin film includes any one or at least two combinations of a hole injection layer, a hole transport layer, an electron blocking layer, a light-emitting layer, an exciton blocking layer, a hole blocking layer, an electron transport layer, and an electron injection layer, and at least one of the light-emitting layers contains any one of the compounds described in 1 to 4 above.

[0037] 7) The organic electroluminescent device according to 5) above, wherein the compound is used as a luminescent material in the luminescent layer of the organic electroluminescent device.

[0038] The superior performance of the compounds of the present invention as luminescent layer materials in organic electroluminescent devices is determined by the following structural design: special groups such as phenanthreneamine, naphthylamine, anthraceneamine, and fluoranthracene are introduced into the peripheral position of the blue boron-nitrogen aromatic fused ring structure. This significantly reduces the T1 energy level (first triplet energy level) of the molecule while maintaining a high T2 energy level (second triplet energy level). Furthermore, the T2 energy level is slightly higher than the S1 energy level (first singlet energy level), minimizing the internal conversion from T2 to T1. This allows excitons to be transported in higher energy level channels during transport and undergo the T2 to S1 energy level transition, greatly improving the utilization rate of excitons by the luminescent molecules and thus enhancing device efficiency.

[0039] The beneficial effects of this invention are: the OLED devices prepared by the compounds of this invention have low start-up voltage, high color purity, high luminous efficiency, and long service life, which can meet the current requirements of the display industry for high-performance materials and show good application prospects. Attached Figure Description

[0040] The accompanying drawings, which are included to provide a further understanding of this application and form part of this application, illustrate exemplary embodiments of this application and are used to explain this application, but do not constitute an undue limitation of this application. In the drawings:

[0041] Figure 1 The diagram below shows the structure of an organic electroluminescent device using the compounds of this invention. The meanings of each layer in the device are as follows:

[0042] 1. Transparent substrate layer; 2. ITO anode layer; 3. Hole injection layer; 4. Hole transport layer A; 5. Hole transport layer B (or electron blocking layer); 6. Light-emitting layer; 7. Electron transport layer B (or hole blocking layer); 8. Electron transport layer A; 9. Electron injection layer; 10. Cathode reflective electrode layer Detailed Implementation

[0043] the term

[0044] In this invention, the alkyl group can be straight-chain or branched. The number of carbon atoms in the alkyl group is not particularly limited, for example, 1 to 50, preferably 1 to 20, and more preferably 1 to 6. Specific examples of alkyl groups include, but are not limited to, methyl, ethyl, propyl, n-propyl, isopropyl, butyl, n-butyl, isobutyl, tert-butyl, sec-butyl, 1-methylbutyl, 1-ethylbutyl, pentyl, n-pentyl, isopentyl, neopentyl, tert-pentyl, hexyl, n-hexyl, 1-methylpentyl, 2-methylpentyl, 4-methyl-2-pentyl, 3,3-dimethylbutyl, 2-ethylbutyl, heptyl, n-heptyl, 1-methylhexyl, cyclopentylmethyl, cyclohexylmethyl, octyl, n-octyl, tert-octyl, 1-methylheptyl, 2-ethylhexyl, 2-propylpentyl, n-nonyl, 2,2-dimethylheptyl, 1-ethylpropyl, 1,1-dimethylpropyl, isohexyl, 4-methylhexyl, and 5-methylhexyl.

[0045] In this invention, the aforementioned alkyl groups may be substituted. For example, the number of carbon atoms in fluorinated alkyl groups and fluorinated alkoxy groups substituted with fluorine is not particularly limited, for example, 1 to 20, more preferably 1 to 6. Examples of fluorinated alkyl groups include, but are not limited to, fluoromethyl, difluoromethyl, trifluoromethyl, trichloromethyl, pentafluoroethyl, 2,2,2-trifluoroethyl, and heptafluoropropyl.

[0046] Alkenyl refers to a hydrocarbon group having one or more carbon-carbon double bonds, comprising substituted or unsubstituted linear or branched structures, with no particular limitation on the number of carbon atoms, for example, from 2 to 20. The alkenyl group can be monounsaturated or polyunsaturated and can have one or more substituents. Specifically, alkenyl groups include, for example: vinyl, propenyl, butenyl, pentenyl, hexenyl, heptenyl, octenyl, nonenyl, decenyl, undecenyl, dodecenyl, tridecenyl, tetradecenyl, pentadecenyl, hexadecenyl, heptadecenyl, octadecenyl, nonadecanyl, eicosene, etc.; and their branched isomers and substituted derivatives (such as haloalkenyl, cyano-substituted alkenyl, alkoxy-substituted alkenyl, aryl-substituted alkenyl, amino-substituted alkenyl, etc.). Preferred alkenyl groups can be straight-chain or branched structures with 2 to 12 carbon atoms, and more preferably lower alkenyl groups with 2 to 6 carbon atoms, such as vinyl, propenyl, n-butenyl, isobutenyl, n-pentenyl, isopentenyl, neopentenyl, etc.

[0047] An alkynyl group refers to a hydrocarbon group having one or more carbon-carbon triple bonds, comprising substituted or unsubstituted linear or branched structures, with no particular limitation on the number of carbon atoms, for example, 2 to 20. The alkynyl group can be a single triple bond (monoyynyl) or contain multiple triple bonds (polyynyl), and can carry one or more substituents. Specifically, alkynyl groups include, for example: ethynyl, propynyl, butynyl, pentyynyl, hexynyl, heptyynyl, octyynyl, nonynyl, decanynyl, undecynyl, dodecaynyl, tridecaynyl, tetradecaynyl, pentadecynyl, hexadecynyl, heptadecaynyl, octadecynyl, nonadecaynyl, eicosynyl, etc.; and their branched isomers and substituted derivatives (such as haloalkynyl, cyano-substituted alkynyl, alkoxy-substituted alkynyl, aryl-substituted alkynyl, amino-substituted alkynyl, etc.). The preferred alkynyl group can be a straight-chain or branched structure with 2 to 12 carbon atoms, and more preferably a lower alkynyl group with 2 to 6 carbon atoms, such as ethynyl, propynyl, n-butynyl, isobutynyl, n-pentynyl, isopentenynyl, neopentynyl, etc.

[0048] The cycloalkyl group can be monocyclic or fused-ring, and the number of carbon atoms is not particularly limited, for example, 3 to 50, preferably 3 to 20, and more preferably 3 to 6. Specific examples include cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, cycloheptyl, and adamantyl, with cyclohexyl being a preferred example.

[0049] The aryl group can be monocyclic or polycyclic, and the number of carbon atoms is not particularly limited, for example, 6 to 50, preferably 6 to 20. Examples of monocyclic aryl groups include, but are not limited to, phenyl, biphenyl, terphenyl, and terphenyl. Examples of polycyclic aryl groups include naphthyl, anthraceneyl, phenanthryl, pyrene, perylene, tetraphenyl, fluorenyl, acenaphathcenyl, triphenylene, and fluoranthyl, but the scope of the invention is not limited thereto.

[0050] A "heterocyclic group" is a cyclic compound group in which one or more atoms in the ring are replaced by heteroatoms other than carbon (such as nitrogen, oxygen, sulfur, etc.). A fused-ring heteroaryl group is a cyclic compound group in which at least two rings (at least one of which is an aromatic ring) share one or more carbon atoms, and at least one ring contains one or more heteroatoms. Examples of heterocyclic groups and fused-ring heteroaryl groups include, but are not limited to, thiophene, furanyl, pyrrole, imidazolyl, triazolyl, azole, diazolyl, triazolyl, pyridinyl, bipyridinyl, pyrimidinyl, triazinyl, acridine, pyridazinyl, quinolinyl, quinazolinyl, quinoxalinyl, phthalazinyl, pyridopyrimidinyl, pyridopyrazinyl, pyrazinopyrazinyl, isoquinolinyl, indolyl, carbazole, benzozolyl, benzazole, benzimidazolyl, benzothiazolyl, benzocarbazole, benzothiaphenyl, dibenzothiaphenyl, benzofuranyl, dibenzofuranyl, thiazolyl, isozolyl, diazolyl, thiadiazolyl, benzothiazolyl, and phenothiazinyl.

[0051] The term silyl is intended to include alkyl-substituted silyl and aryl-substituted silyl. Specific examples of such silyls include trimethylsilyl, triethylsilyl, triphenylsilyl, trimethoxysilyl, dimethoxyphenylsilyl, diphenylmethylsilyl, diphenylvinylsilyl, methylcyclobutylsilyl, and dimethylfuranylsilyl.

[0052] The principles and features of the present invention will be further illustrated below with several synthetic embodiments. The embodiments are only used to explain the present invention, but are not intended to limit the scope of the present invention.

[0053] Synthesis Example:

[0054] Synthesis Example 1: Synthesis of Chemical 5

[0055]

[0056] Synthesis of intermediate 1a: 13.5 g of N-phenyl-9-phenanthreneamine, 9.5 g of 3-chloro-1-bromobenzene, 0.9 g of tris(dibenzylacetone)dipalladium, 0.4 g of tri-tert-butylphosphine, and 6.2 g of sodium tert-butoxide were weighed into a flask. 200 mL of toluene was added, and the mixture was purged under nitrogen protection at 80 °C for 6 h. The reaction was stopped, cooled to room temperature, extracted with ethyl acetate and water, concentrated by rotary evaporation, and purified by silica gel column chromatography to give 14 g of product (75% yield). The molecular weight was determined by mass spectrometry to be m / z = 380.9 (M+H). + .

[0057] Synthesis of intermediate 1b: 19 g of intermediate 1a, 7.5 g of 4-tert-butylaniline, 0.9 g of tris(dibenzylacetone)dipalladium, 0.4 g of tri-tert-butylphosphine, and 6.2 g of sodium tert-butoxide were weighed into a flask. 200 mL of toluene was added, and the mixture was refluxed at 100 °C for 20 h under nitrogen protection. The reaction was stopped, cooled to room temperature, extracted with ethyl acetate and water, concentrated by rotary evaporation, and purified by silica gel column chromatography to give 17.2 g of product (70% yield). The molecular weight was determined by mass spectrometry to be m / z = 493.7 (M+H). + .

[0058] Synthesis of intermediate 1c: 24.6 g of intermediate 1b, 21.3 g of N-(4-(tert-butyl)phenyl)-2,3-dichloroaniline, 0.9 g of tris(dibenzylacetone)dipalladium, 0.4 g of tri-tert-butylphosphine, and 6.2 g of sodium tert-butoxide were weighed into a flask. 200 mL of toluene was added, and the mixture was refluxed at 100 °C for 20 h under nitrogen protection. The reaction was stopped, cooled to room temperature, extracted with ethyl acetate and water, concentrated by rotary evaporation, and purified by silica gel column chromatography to give 15 g of product (35% yield). The molecular weight was determined by mass spectrometry to be m / z = 883.6 (M+H). + .

[0059] Synthesis of Chemical 5: 4.4 g of intermediate 1c was weighed and dissolved in 40 mL of dry xylene. Under nitrogen protection, 5 mL of n-butyllithium solution (2.5 M) was added dropwise at -20 °C, and the mixture was stirred at low temperature for 1 h, then at room temperature for 1 h. The mixture was then returned to -20 °C, and 3.75 g of boron tribromide was added. The mixture was stirred at low temperature for 1 h, then at room temperature for 2 h. 2.6 g of diisopropylethylamine was then added, and the mixture was heated to 100 °C for 6 h. The reaction was stopped, cooled to room temperature, and neutralized with sodium carbonate solution. The mixture was extracted three times with dichloromethane, and the organic phase was collected. The solvent was evaporated, and the crude product was separated by silica gel column chromatography. Recrystallization from dichloromethane / ethanol yielded 1.0 g of the target product. The yield was 23%, and the molecular weight, determined by mass spectrometry, was m / z = 857.0 (M+H). + .

[0060] Synthesis Example 2: Synthesis of Chemical 16

[0061]

[0062] Synthesis of intermediate 2a: 17.3 g of N-(1,1'-diphenyl)-9-phenanthreneamine, 9.5 g of 3-chloro-1-bromobenzene, 0.9 g of tris(dibenzylacetone)dipalladium, 0.4 g of tri-tert-butylphosphine, and 6.2 g of sodium tert-butoxide were weighed into a flask. 200 mL of toluene was added, and the mixture was purged under nitrogen protection at 90 °C for 5 h. The reaction was stopped, cooled to room temperature, extracted with ethyl acetate and water, concentrated by rotary evaporation, and purified by silica gel column chromatography to give 16 g of product (70% yield). The molecular weight was determined by mass spectrometry to be m / z = 457.0 (M+H). + .

[0063] Synthesis of intermediate 2b: 22.8 g of intermediate 2a, 7.5 g of 4-tert-butylaniline, 0.8 g of tris(dibenzylacetone)dipalladium, 0.45 g of tri-tert-butylphosphine, and 6.5 g of sodium tert-butoxide were weighed into a flask. 200 mL of toluene was added, and the mixture was refluxed at 110 °C for 8 h under nitrogen protection. The reaction was stopped, cooled to room temperature, extracted with ethyl acetate and water, concentrated by rotary evaporation, and purified by silica gel column chromatography to give 17 g of product, with a yield of 60%. The molecular weight was determined by mass spectrometry to be m / z = 569.8 (M+H). + .

[0064] Synthesis of intermediate 2c: 28 g of intermediate 2b, 21.3 g of N-(4-(tert-butyl)phenyl)-4,5-dichloro-[1,1'-biphenyl]-3-aniline, 0.8 g of tris(dibenzylacetone)dipalladium, 0.45 g of tri-tert-butylphosphine, and 6.5 g of sodium tert-butoxide were weighed into a flask. 200 mL of toluene was added, and the mixture was refluxed at 110 °C for 8 h under nitrogen protection. The reaction was stopped, cooled to room temperature, extracted with ethyl acetate and water, concentrated by rotary evaporation, and purified by silica gel column chromatography to give 20.7 g of product, with a yield of 40%. The molecular weight was determined by mass spectrometry to be m / z = 1035.8 (M+H). + .

[0065] Synthesis of Chemical 16: 5.2 g of intermediate 2c was weighed and dissolved in 50 mL of dry xylene. Under nitrogen protection, 6 mL of n-butyllithium solution (2.5 M) was added dropwise at -30 °C, and the mixture was stirred at low temperature for 2 h, then at room temperature for 2 h. The mixture was then returned to -30 °C, and 4 g of boron tribromide was added. The mixture was stirred at low temperature for 1 h, then at room temperature for 2 h. 3 g of diisopropylethylamine was then added, and the mixture was heated to 80 °C for 8 h. The reaction was stopped, cooled to room temperature, and neutralized with sodium carbonate solution. The mixture was extracted three times with dichloromethane, and the organic phase was collected. The solvent was evaporated, and the crude product was separated by silica gel column chromatography. Recrystallization from dichloromethane / ethanol yielded 1.0 g of the target product. The yield was 20%, and the molecular weight, determined by mass spectrometry, was m / z = 1009.2 (M+H). + .

[0066] Synthesis Example 3: Synthesis of Chemical 124

[0067]

[0068] Synthesis of intermediate 3a: 18.5 g of N-[1,1'-diphenyl]yl-2-pyrene, 9.5 g of 3-chloro-1-bromobenzene, 0.7 g of tris(dibenzylacetone)dipalladium, 0.35 g of tri-tert-butylphosphine, and 5.8 g of sodium tert-butoxide were weighed into a flask. 200 ml of toluene was added, and the mixture was purged under nitrogen protection at 95 °C for 6 h. The reaction was stopped, cooled to room temperature, extracted with ethyl acetate and water, concentrated by rotary evaporation, and purified by silica gel column chromatography to give 18.7 g of product (78% yield). The molecular weight was determined by mass spectrometry to be m / z = 481.0 (M+H). + .

[0069] Synthesis of intermediate 3b: 24 g of intermediate 3a, 7.5 g of 4-tert-butylaniline, 0.7 g of tris(dibenzylacetone)dipalladium, 0.35 g of tri-tert-butylphosphine, and 5.8 g of sodium tert-butoxide were weighed into a flask. 200 mL of toluene was added, and the mixture was refluxed at 105 °C for 12 h under nitrogen protection. The reaction was stopped, cooled to room temperature, extracted with ethyl acetate and water, concentrated by rotary evaporation, and purified by silica gel column chromatography to give 13.3 g of product, with a yield of 45%. The molecular weight was determined by mass spectrometry to be m / z = 593.8 (M+H).+ .

[0070] Synthesis of intermediate 3c: 30 g of intermediate 3b, 22 g of N,N'-2,3-dichloro-5-methyl-di(4-(tert-butyl)phenyl)amine, 0.7 g of tris(dibenzylacetone)dipalladium, 0.35 g of tri-tert-butylphosphine, and 5.8 g of sodium tert-butoxide were weighed into a flask. 200 ml of toluene was added, and the mixture was refluxed at 105 °C for 12 h under nitrogen protection. The reaction was stopped, cooled to room temperature, extracted with ethyl acetate and water, concentrated by rotary evaporation, and purified by silica gel column chromatography to obtain 18 g of product, with a yield of 36%. The molecular weight was determined by mass spectrometry to be m / z = 997.8 (M+H). + .

[0071] Synthesis of Chemical 124: 5.0 g of intermediate 3C was weighed and dissolved in 80 mL of dry xylene. Under nitrogen protection, 6 mL of n-butyllithium solution (2.5 M) was added dropwise at -50 °C, with stirring at low temperature for 1.5 h, followed by stirring at room temperature for 1.5 h. The mixture was then returned to -50 °C, and 4 g of boron tribromide was added. The mixture was stirred at low temperature for 1.5 h, followed by stirring at room temperature for 1.5 h. Then, 3.5 g of diisopropylethylamine was added, and the mixture was heated to 85 °C for 9 h. The reaction was stopped, cooled to room temperature, and neutralized with sodium carbonate solution. The mixture was extracted three times with dichloromethane, and the organic phase was collected. The solvent was evaporated, and the crude product was separated by silica gel column chromatography. Recrystallization from dichloromethane / ethanol yielded 1.1 g of the target product. The yield was 23%, and the molecular weight determined by mass spectrometry was m / z = 971.1 (M+H). + .

[0072] Synthesis Example 4: Synthesis of Chemical 200

[0073]

[0074] Synthesis of intermediate 4a: 18.5 g of N-[1,1'-diphenyl]yl-2-pyrene, 9.5 g of 3-chloro-1-bromobenzene, 1 g of tris(dibenzylacetone)dipalladium, 0.5 g of tri-tert-butylphosphine, and 6.5 g of sodium tert-butoxide were weighed into a flask. 200 mL of toluene was added, and the mixture was purged under nitrogen protection at 110 °C for 4 h. The reaction was stopped, cooled to room temperature, extracted with ethyl acetate and water, concentrated by rotary evaporation, and purified by silica gel column chromatography to give 20.4 g of product (85% yield). The molecular weight was determined by mass spectrometry to be m / z = 481.0 (M+H). + .

[0075] Synthesis of intermediate 4b: 24 g of intermediate 4a, 7.5 g of 4-tert-butylaniline, 1 g of tris(dibenzylacetone)palladium, 0.5 g of tri-tert-butylphosphine, and 6.5 g of sodium tert-butoxide were weighed into a flask. 200 mL of toluene was added, and the mixture was refluxed at 120 °C for 10 h under nitrogen protection. The reaction was stopped, cooled to room temperature, extracted with ethyl acetate and water, concentrated by rotary evaporation, and purified by silica gel column chromatography to give 16.3 g of product, with a yield of 55%. The molecular weight was determined by mass spectrometry to be m / z = 593.8 (M+H). + .

[0076] Synthesis of intermediate 4c: 30 g of intermediate 4b, 27.5 g of 8-(tert-butyl)-N-(4-(tert-butyl)phenyl)-N-(2,3-dichloro-5-fluorophenyl)dibenzo[b,d]thiophene-2-amine, 1 g of tris(dibenzylacetone)dipalladium, 0.5 g of tri-tert-butylphosphine, and 6.5 g of sodium tert-butoxide were weighed into a flask. 200 mL of toluene was added, and the mixture was refluxed at 120 °C for 10 h under nitrogen protection. The reaction was stopped, cooled to room temperature, extracted with ethyl acetate and water, concentrated by rotary evaporation, and purified by silica gel column chromatography to give 17.7 g of product, with a yield of 32%. The molecular weight was determined by mass spectrometry to be m / z = 1107.9 (M+H). + .

[0077] Synthesis of Chemical 200: 5.5 g of intermediate 4C was weighed and dissolved in 60 mL of dry xylene. Under nitrogen protection, 5.5 mL of n-butyllithium solution (2.5 M) was added dropwise at -10 °C, with stirring at low temperature for 0.5 h, followed by stirring at room temperature for 0.5 h. The mixture was then returned to -10 °C, and 4.2 g of boron tribromide was added, with stirring at low temperature for 0.5 h, followed by stirring at room temperature for 0.5 h. Then, 3 g of diisopropylethylamine was added, and the mixture was heated to 95 °C for 6 h. The reaction was stopped, cooled to room temperature, and neutralized with sodium carbonate solution. The mixture was extracted three times with dichloromethane, and the organic phase was collected. The solvent was evaporated, and the crude product was separated by silica gel column chromatography. Recrystallization from dichloromethane / ethanol yielded 0.7 g of the target product. The yield was 13%, and the molecular weight determined by mass spectrometry was m / z = 1081.2 (M+H). + .

[0078] Synthesis Example 5: Synthesis of Chemical 286

[0079]

[0080] Synthesis of intermediate 5a: 17.3 g of N-(1',1-diphenyl)-10-phenylanthracene-9-amine, 9.5 g of 3-chloro-1-bromobenzene, 0.9 g of tris(dibenzylacetone)dipalladium, 0.45 g of tri-tert-butylphosphine, and 5.5 g of sodium tert-butoxide were weighed into a flask. 200 ml of toluene was added, and the mixture was purged under nitrogen protection at 90 °C for 10 h. The reaction was stopped, cooled to room temperature, extracted with ethyl acetate and water, concentrated by rotary evaporation, and purified by silica gel column chromatography to give 17.8 g of product (78% yield). The molecular weight was determined by mass spectrometry to be m / z = 457.0 (M+H). + .

[0081] Synthesis of intermediate 5b: 23 g of intermediate 5a, 7.5 g of 4-tert-butylaniline, 0.9 g of tris(dibenzylacetone)dipalladium, 0.45 g of tri-tert-butylphosphine, and 5.5 g of sodium tert-butoxide were weighed into a flask. 200 mL of toluene was added, and the mixture was refluxed at 115 °C for 9 h under nitrogen protection. The reaction was stopped, cooled to room temperature, extracted with ethyl acetate and water, concentrated by rotary evaporation, and purified by silica gel column chromatography to give 14 g of product, with a yield of 43%. The molecular weight was determined by mass spectrometry to be m / z = 658.9 (M+H). + .

[0082] Synthesis of intermediate 5c: 33 g of intermediate 5b, 27.5 g of 8-(tert-butyl)-N-(4-(tert-butyl)phenyl)-N-(2,3-dichlorophenyl)dibenzo[b,d]furan-2-amine, 0.9 g of tris(dibenzylacetone)dipalladium, 0.45 g of tri-tert-butylphosphine, and 5.5 g of sodium tert-butoxide were weighed into a flask. 200 mL of toluene was added, and the mixture was refluxed at 110 °C for 9 h under nitrogen protection. The reaction was stopped, cooled to room temperature, extracted with ethyl acetate and water, concentrated by rotary evaporation, and purified by silica gel column chromatography to give 15.7 g of product, with a yield of 28%. The molecular weight was determined by mass spectrometry to be m / z = 1125.9 (M+H). + .

[0083] Synthesis of Chemical 286: 5.6 g of intermediate 5c was weighed and dissolved in 40 mL of dry xylene. Under nitrogen protection, 5 mL of n-butyllithium solution (2.5 M) was added dropwise at -25 °C, and the mixture was stirred at low temperature for 4 h, then at room temperature for 4 h. The mixture was then returned to -25 °C, and 4.8 g of boron tribromide was added. The mixture was stirred at low temperature for 4 h, then at room temperature for 4 h. Then, 3.6 g of diisopropylethylamine was added, and the mixture was heated to 105 °C for 4 h. The reaction was stopped, cooled to room temperature, and neutralized with sodium carbonate solution. The mixture was extracted three times with dichloromethane, and the organic phase was collected. The solvent was evaporated, and the crude product was separated by silica gel column chromatography. Recrystallization from dichloromethane / ethanol yielded 0.9 g of the target product. The yield was 17%, and the molecular weight determined by mass spectrometry was m / z = 1099.2 (M+H). + .

[0084] Synthesis Example 6: Synthesis of Chemical 371

[0085]

[0086] Synthesis of intermediate 6a: 14.7 g of N-phenylfluoranthracene-3-amine, 15.5 g of 3-bromo-6-tert-butylcarbazole, 1.1 g of tris(dibenzylacetone)dipalladium, 0.55 g of tri-tert-butylphosphine, and 7 g of sodium tert-butoxide were weighed into a flask. 200 mL of toluene was added, and the mixture was purged under nitrogen protection at 100 °C for 8 h. The reaction was stopped, cooled to room temperature, extracted with ethyl acetate and water, concentrated by rotary evaporation, and purified by silica gel column chromatography to give 19 g of product (74% yield). The molecular weight was determined by mass spectrometry to be m / z = 515.7 (M+H). + .

[0087] Synthesis of intermediate 6b: 30 g of intermediate 6a, 21.2 g of 3,6-di-tert-butyl-9-(2,3-dichlorophenyl)-9H-carbazole, 1.1 g of tris(dibenzylacetone)dipalladium, 0.55 g of tri-tert-butylphosphine, and 7 g of sodium tert-butoxide were weighed into a flask. 200 mL of toluene was added, and the mixture was refluxed at 100 °C for 8 h under nitrogen protection. The reaction was stopped, cooled to room temperature, extracted with ethyl acetate and water, concentrated by rotary evaporation, and purified by silica gel column chromatography to give 18 g of product, with a yield of 40%. The molecular weight was determined by mass spectrometry to be m / z = 903.6 (M+H). + .

[0088] Synthesis of Chemical 371: 4.5 g of intermediate 6b was weighed and dissolved in 60 mL of dry xylene. Under nitrogen protection, 5 mL of n-butyllithium solution (2.5 M) was added dropwise at -35 °C, and the mixture was stirred at low temperature for 1 h, then at room temperature for 1 h. The temperature was then returned to -20 °C, and 4.5 g of boron tribromide was added. The mixture was stirred at low temperature for 1 h, then at room temperature for 1 h. Then, 3.2 g of diisopropylethylamine was added, and the mixture was heated to 85 °C for 10 h. The reaction was stopped, cooled to room temperature, and neutralized to neutral with sodium carbonate solution. The mixture was extracted three times with dichloromethane, and the organic phase was collected. The solvent was evaporated, and the crude product was separated by silica gel column chromatography. Recrystallization from dichloromethane / ethanol yielded 0.65 g of the target product. The yield was 15%, and the molecular weight determined by mass spectrometry was m / z = 877.0 (M+H). + .

[0089] Device Examples 1-25: Fabrication of Organic Electroluminescent Devices Used as Light-Emitting Layer Materials

[0090] A 25mm × 75mm × 1.1mm thick glass substrate with an indium tin oxide (ITO) transparent electrode (anode) was ultrasonically cleaned in isopropanol for 5 minutes, followed by ultraviolet (UV)-ozone cleaning for 30 minutes. The cleaned glass substrate was then mounted on the substrate holder of a vacuum evaporation apparatus, and a vacuum of 1 × 10⁻⁶ was applied. -5 ~1×10 -6Pa, a hole injection layer (HIL) HATCN is deposited on an ITO transparent conductive layer. A hole transport layer (HTL) is deposited on the hole injection layer. Then, an electron blocking layer (EBL) is deposited on the hole transport layer. Then, a light-emitting layer (EML) is co-deposited on the electron blocking layer. The light-emitting layer (EML) uses a multi-source co-deposition method to deposit the light-emitting material and the host material (H), wherein the doping concentration of the light-emitting material is 2wt%. Then, a hole blocking layer (HBL) is deposited on the light-emitting layer. Then, an electron transport material (ETL) and lithium 8-hydroxyquinoline (Liq) are deposited on the hole blocking layer in a doping ratio of 1:1. Then, an electron injection electrode (EIL) Liq is deposited on the ETL. Then, a metal cathode aluminum (Al) is deposited on the EIL. The structure of the organic electroluminescent device in Example 1 is as follows. Figure 1 As shown, Figure 1 The stacking order and function of each functional layer are also shown. The molecular structure of the material used in OLED is shown in Table 1.

[0091] Table 1 Materials used in OLEDs

[0092]

[0093] The specific device structure of Device Example 1 is: ITO(130) / HATCN(15) / HTL(60) / EBL(40) / H:Liq(40,2wt%) / HBL(5) / ETL:Liq(30,40wt%) / Liq(1) / Al(100). It should be noted that the numbers in parentheses represent the film thickness (unit: nm).

[0094] The only difference between Device Examples 2 to 25 and Device Example 1 is that the compound 5 of the present invention used in the light-emitting layer is replaced with other compounds of the present invention, as detailed in Table 2.

[0095] Comparative Examples 1-5:

[0096] The comparative example differs from device embodiment 1 in that component 1 in the organic electroluminescent device is replaced with industry-known R-1 to R-5, and the resulting device performance test data are shown in Table 2. The OLED was characterized using standard methods. For this purpose, the electroluminescence spectrum, current efficiency (measured in cd / A), power efficiency (measured in lm / W), and external quantum efficiency (EQE, measured as a percentage) were determined, calculated as a function of luminous density from the current / voltage / luminous density characteristic line (IUL characteristic line) exhibiting Lambertian emission characteristics. EQE1000 represents 1000 cd / m². 2 The external quantum efficiency at operating brightness, T95 indicates the device's efficiency at 1000 cd / m². 2The operating time when the device brightness decreases to 95% from the initial brightness, Peak and FWHM values ​​indicate the device's operating time at 1000 cd / m². 2 The emission peak and spectral half-width are shown in Table 2. The device performance of Examples 1-15 and Comparative Example 1 of the present invention is summarized in Table 2.

[0097] Table 2. Device characteristic results of the examples and comparative examples

[0098]

[0099]

[0100] Table 3. Energy levels of the luminescent molecules used in the Examples and Comparative Examples

[0101]

[0102]

[0103] Compared to Comparative Examples 1-5, the compounds of the present invention exhibit narrow-band blue light emission in single-host system devices (Examples 1-25), while maintaining the same device lifetime and significantly improving efficiency. The main reason for this is the introduction of special groups such as phenanthreneamine, naphthylamine, anthraceneamine, and fluoranthracene into the peripheral positions of the blue-light boron-nitrogen aromatic fused-ring structure. This significantly lowers the T1 energy level of the molecule (see Table 3) while maintaining a relatively high T2 energy level (slightly higher than the S1 energy level), minimizing internal conversions from T2 to T1. This allows excitons to transport primarily through higher energy channels and undergo T2-to-S1 transitions, greatly improving the utilization rate of excitons by the luminescent molecules and thus enhancing device efficiency.

Claims

1. A fused heterocyclic compound, characterized in that, The compound is represented by the general formula D1, D2 or D3: X1 is represented by the following general formulas E1, E2, E3, and E4: R1~R 17 The groups are independently selected from hydrogen atoms, deuterium atoms, fluorine atoms, substituted silyl groups with 1 to 50 carbon atoms, substituted or unsubstituted alkyl groups with 1 to 50 carbon atoms, substituted or unsubstituted alkenyl groups with 1 to 20 carbon atoms, substituted or unsubstituted alkynyl groups with 2 to 20 carbon atoms, substituted or unsubstituted alkoxy groups with 1 to 50 carbon atoms, substituted or unsubstituted fluoroalkyl groups with 1 to 20 carbon atoms, substituted or unsubstituted fluoroalkoxy groups with 1 to 20 carbon atoms, substituted or unsubstituted cycloalkyl groups with 3 to 50 cyclic carbon atoms, substituted or unsubstituted aryl groups with 6 to 50 cyclic carbon atoms, and substituted or unsubstituted monovalent heterocyclic groups with 5 to 50 cyclic carbon atoms. Y1 is either O or S.

2. The fused heterocyclic compound according to claim 1, characterized in that, The R1~R 17 The substituents are independently selected from: hydrogen atom, deuterium atom, chlorine atom, bromine atom, fluorine atom, cyano, nitro, substituted silyl group, substituted or unsubstituted methyl, substituted or unsubstituted ethyl, substituted or unsubstituted n-propyl, substituted or unsubstituted isopropyl, substituted or unsubstituted n-butyl, substituted or unsubstituted isobutyl, substituted or unsubstituted sec-butyl, substituted or unsubstituted tert-butyl, substituted or unsubstituted 2-methylbutyl, substituted or unsubstituted n-pentyl, substituted or unsubstituted sec-pentyl, substituted or unsubstituted trifluoromethyl, etc. Substituted or unsubstituted pentafluoroethyl, substituted or unsubstituted 2,2,2-trifluoroethyl, substituted or unsubstituted vinyl, substituted or unsubstituted propenyl, substituted or unsubstituted n-butenyl, substituted or unsubstituted isobutenyl, substituted or unsubstituted n-pentenyl, substituted or unsubstituted isopentenyl, substituted or unsubstituted neopentenyl, substituted or unsubstituted ethynyl, substituted or unsubstituted propynyl, substituted or unsubstituted n-butynyl, substituted or unsubstituted isobutynyl, substituted or unsubstituted n-pentynyl, substituted or unsubstituted isopentenynyl Substituted or unsubstituted neopentynyl, substituted or unsubstituted cyclopropyl, substituted or unsubstituted cyclobutyl, substituted or unsubstituted cyclopentyl, substituted or unsubstituted cyclohexyl, substituted or unsubstituted adamantyl, substituted or unsubstituted thiophene, substituted or unsubstituted indolyl, substituted or unsubstituted furanyl, substituted or unsubstituted phenyl, substituted or unsubstituted pyridyl, substituted or unsubstituted biphenyl, substituted or unsubstituted naphthyl, substituted or unsubstituted anthraceneyl, substituted or unsubstituted phenanthryl, substituted or unsubstituted indenyl, substituted or unsubstituted Substituted fluorenyl, substituted or unsubstituted spirodifluorenyl, substituted or unsubstituted indofluorenyl, substituted or unsubstituted fluoranyl, substituted or unsubstituted pyrene, substituted or unsubstituted peryl, substituted or unsubstituted tetraphenyl, substituted or unsubstituted benzothiophene, substituted or unsubstituted benzothiophene, substituted or unsubstituted benzofuranyl, substituted or unsubstituted dibenzothiophene, substituted or unsubstituted dibenzothiophene, substituted or unsubstituted dibenzofuranyl, substituted or unsubstituted dibenzoselenyl, and substituted or unsubstituted carbazoyl.

3. The fused heterocyclic compound according to claims 1-2, characterized in that, In the fused heterocyclic compounds, "substituted or unsubstituted" means that the substituent is independently selected from deuterium, tritium, halogen, cyano, nitro, hydroxyl, monovalent alkyl or cycloalkyl with 1 to 10 carbon atoms, monovalent monocyclic aryl or fused aryl with 6 to 30 carbon atoms, or monovalent heterocyclic or fused heteroaryl with 2 to 50 carbon atoms.

4. The fused heterocyclic compound according to any one of claims 1 to 3, characterized in that, The fused heterocyclic compounds are selected from the following structures:

5. An organic electroluminescent device, characterized in that, The organic electroluminescent device includes an anode, a cathode, and at least one organic thin film located between the anode and the cathode, wherein the organic thin film contains the compound according to any one of claims 1 to 4.

6. The organic electroluminescent device according to claim 5, characterized in that, The organic thin film includes any one or at least two combinations of a hole injection layer, a hole transport layer, an electron blocking layer, a light-emitting layer, an exciton blocking layer, a hole blocking layer, an electron transport layer, and an electron injection layer, and at least one of the light-emitting layers contains the compound of any one of claims 1 to 4.

7. The organic electroluminescent device according to claim 5, characterized in that, The compound is used as a luminescent material in the luminescent layer of organic electroluminescent devices.

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