Boron-nitrogen compound, application thereof and organic electroluminescent device containing compound

Abstract

The invention relates to a boron-nitrogen compound, application thereof and an organic electroluminescent device containing the compound, in particular to a blue fluorescent luminescent material with high efficiency and long service life. The material is optimally designed in the following manner: firstly, replacing a triarylamine unit at a boron para-position in DABNA-2 (CAS: 1689553-04-5) with a spirofluorene indole acridine unit, and carrying out monosubstitution or polysubstitution on a carbazole part of the spirofluorene indole acridine unit; and secondly, replacing the biphenyl unit at the boron para-position with a substituted benzothiophene unit. Through the design, the luminous efficiency and the device stability are optimized, so that the service life of the device is remarkably prolonged.

Description

Technical Field

[0001] The invention relates to the technical field of organic electroluminescence, and in particular to a novel organic compound and application thereof, and an organic electroluminescence device containing the compound. Background Art

[0002] OLED display panels, which are composed of organic light-emitting diodes (OLED), have the advantages of low power consumption, wide color gamut, and high brightness. After nearly ten years of technological iterations, their commercial applications are becoming more and more extensive. Specifically, under the action of the electric field, the electron and hole carriers generated by the cathode and anode of OLED move relative to each other, and meet and recombine into excitons in the light-emitting layer through the electron transport layer and the hole transport layer. The excitons generate photons through radiation, thereby generating visible light. OLED has the characteristics of self-luminescence, wide viewing angle, rollability, and short response time. It has great advantages in large-size and / or flexible ultra-thin panels. It is a new display technology that is rapidly developing and has a high degree of process integration. It has been widely used in display products such as TVs, smart phones, tablets, car displays, and lighting. It will also be further used in creative display products such as large-size displays and flexible screens.

[0003] OLED devices are composed of three colors: red, green, and blue. However, the life of phosphorescent materials for blue light cannot meet commercial requirements. Therefore, blue light materials are still mainly fluorescent materials. Since the exciton utilization rate of fluorescent materials is only 25%, in order to obtain higher efficiency, top-emitting device structures are widely used. That is, under fixed color coordinates, the narrower the intrinsic spectrum of the material, the higher the device efficiency. Therefore, narrow spectrum materials have become an effective solution for scientific researchers to develop high-efficiency blue light materials. Due to the weak electronic properties of boron and nitrogen atoms, boron nitrogen materials (DOI: 10.1002 / adma.201505491) show multiple resonances of the entire molecule, which not only makes the HOMO / LUMO electron cloud distribution more uniform, but also makes the non-radiative vibration of the molecule suppressed to a large extent, so that the half-peak width of the spectrum of the entire molecule is very narrow and has a lower shoulder peak. Summary of the invention

[0004] The present invention mainly designs a high-efficiency, long-life blue fluorescent luminescent material. First, a triarylamine unit in a boron-para-position of DABNA-2 (CAS: 1689553-04-5) is replaced with a spirofluorene indole acridine unit, and the hydrogen on the carbazole part of the spirofluorene indole acridine unit is monosubstituted or polysubstituted. Secondly, the biphenyl unit in the boron-para-position is replaced with a substituted benzothiophene unit. Specifically, the present invention provides:

[0005] 1) A fused heterocyclic compound, characterized in that the fused heterocyclic compound is represented by the following general formula (1):

[0006]

[0007] R1 represents hydrogen, substituted or unsubstituted alkyl, substituted or unsubstituted silyl;

[0008] R2 to R6 independently represent hydrogen, substituted or unsubstituted alkyl, substituted or unsubstituted silyl, substituted or unsubstituted aryl, substituted or unsubstituted heteroaryl, substituted or unsubstituted diphenylamino, and adjacent groups may form a ring; a, b, c, d, e are independently 0 to 4;

[0009] Ar1 and Ar2 each independently represent a substituted or unsubstituted aryl group, or a substituted or unsubstituted heteroaryl group;

[0010] The entire molecule may be deuterated or undeuterated.

[0011] 2) According to the fused heterocyclic compound for an organic electroluminescent device described in 1) above, wherein R1 represents a substituted or unsubstituted alkyl group having 1 to 6 carbon atoms, preferably a methyl group, a tert-butyl group, an isopentyl group, etc.

[0012] 3) According to the fused heterocyclic compound for organic electroluminescent devices described in 1) above, wherein R2 to R6 represent substituted or unsubstituted alkyl groups having 1 to 6 carbon atoms, substituted or unsubstituted phenyl groups; preferably tert-butyl group, phenyl group, o-methylphenyl group, p-tert-butylphenyl group, m-tert-butylphenyl group, etc.

[0013] 4) According to the fused heterocyclic compound for an organic electroluminescent device described in 1) above, wherein Ar1 and Ar2 each independently represent a substituted or unsubstituted phenyl group; preferably tert-butylphenyl, tetramethylnaphthyl, 2-phenyl-4-tert-butylphenyl, 9,9-dimethylfluorenyl, etc.

[0014] 5) According to the fused heterocyclic compound for an organic electroluminescent device described in 1) above, the "substituted" in the "substituted or unsubstituted" in the compound means that the substituent is independently selected from a deuterium atom, a tritium atom, a halogen atom, a cyano group, a nitro group, a hydroxyl group, a monovalent alkyl group or a cycloalkyl group having 1 to 10 carbon atoms, a monovalent monocyclic aromatic group or a condensed aromatic group having 6 to 30 carbon atoms, and a monovalent heterocyclic group or a condensed heteroaryl group having 2 to 50 carbon atoms.

[0015] 6) The fused heterocyclic compound for an organic electroluminescent device according to 1) above, wherein the fused heterocyclic compound is selected from the following structures:

[0016]

[0017]

[0018]

[0019]

[0020]

[0021]

[0022]

[0023]

[0024]

[0025]

[0026]

[0027] 7) 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, and the organic thin film contains the compound described in any one of 1) to 6) above.

[0028] 8) The organic electroluminescent device according to 7) above, wherein the compound is used as a light-emitting material in the organic electroluminescent device.

[0029] Compared with the prior art, the beneficial effects of the present invention are as follows: first, relative to triphenylamine, the spirofluorene indole acridine unit has good electron-donating properties and rigidity, which can further expand the degree of multiple resonance and improve the radiation rate, thereby improving the efficiency of the device; at the same time, after the hydrogen substitution on the carbazole part of the spirofluorene indole acridine unit, aggregation can be suppressed and the HOMO / LUMO energy level and luminescence spectrum can be regulated. Secondly, relative to phenyl, the benzothiophene unit has a lower triplet energy level, which can quench excessive triplet excitons, thereby improving the stability of the device. Therefore, by adjusting and optimizing a variety of units, the efficiency and life of the device are effectively improved. In addition, in top-emitting devices, the device efficiency is affected by the spectrum and energy level of the luminescent material. The material of the present invention is more matched with the commercial device structure in terms of spectrum and energy level, thereby obtaining high-efficiency and long-life device performance. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] The drawings described herein are used to provide a further understanding of the present application and constitute a part of the present application. The illustrative embodiments of the present application and their descriptions are used to explain the present application and do not constitute an improper limitation on the present application. In the drawings:

[0031] Figure 1This is a schematic diagram of the structure of an organic electroluminescent device to which the compound of the present invention is applied, wherein the meanings of the various layers of the device structure are as follows:

[0032] 1. 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, 11. Light coupling layer, 12. Package cover layer. DETAILED DESCRIPTION

[0033] the term

[0034] In the present invention, the alkyl group may be linear or branched. The number of carbon atoms in the alkyl group is not particularly limited, and is, 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.

[0035] Alkoxy refers to -O-alkyl, wherein the number of carbon atoms is not particularly limited, for example, 1 to 50, preferably 1 to 20, more preferably 1 to 6. Examples of alkoxy include, but are not limited to, methoxy, ethoxy, propoxy (eg, n-propoxy and isopropoxy), and tert-butoxy.

[0036] In the present invention, the above-mentioned alkyl or alkoxy group may be substituted. For example, in the fluorinated alkyl group and the fluorinated alkoxy group substituted with fluorine, the number of carbon atoms 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. Examples of fluorinated alkoxy groups include, but are not limited to, trifluoromethoxy, 2,2,2-trifluoroethoxy, and pentafluoroethoxy.

[0037] The cycloalkyl group may be a monocyclic ring or a condensed ring, and the number of carbon atoms therein is not particularly limited, and is, 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, and cyclohexyl is preferred.

[0038] The aryl group may be a monocyclic or polycyclic aryl group, wherein 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, anthracenyl, phenanthrenyl, pyrenyl, perylenyl, tetraphenyl, fluorenyl, acenaphthenyl, triphenylene and fluoranthene, but the scope of the present invention is not limited thereto. Heteroaryl refers to an aryl group containing other elements (such as nitrogen, oxygen, sulfur, etc.) replacing carbon atoms in the aromatic ring. There is no particular limitation on the number of carbon atoms, for example, 2 to 50, preferably 4 to 20.

[0039] "Heterocyclyl" refers to 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 refers to 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, thienyl, furanyl, pyrrolyl, imidazolyl, triazolyl, oxazolyl, oxadiazolyl, triazolyl, pyridyl, bipyridyl, pyrimidyl, triazinyl, triazolyl, acridinyl, pyridazinyl, pyrazinyl, quinolyl, quinazolinyl, quinoxalinyl, phthalazinyl, pyridopyrimidinyl, pyridopyrazinyl, pyrazinopyrazinyl, isoquinolyl, indolyl, carbazolyl, benzoxazolyl, benzimidazolyl, benzothiazolyl, benzocarbazolyl, benzothienyl, dibenzothienyl, benzofuranyl, dibenzofuranyl, thiazolyl, isoxazolyl, oxadiazolyl, thiadiazolyl, benzothiazolyl, and phenothiazinyl.

[0040] Silyl is intended to include alkyl-substituted silyl and aryl-substituted silyl. Specific examples of such silyl include trimethylsilyl, triethylsilyl, triphenylsilyl, trimethoxysilyl, dimethoxyphenylsilyl, diphenylmethylsilyl, diphenylvinylsilyl, methylcyclobutylsilyl, and dimethylfurylsilyl.

[0041] "Deuterated" or "deuterated or not deuterated" refers to one or more deuterated or fully deuterated.

[0042] The specific synthesis steps are as follows:

[0043] Synthesis Example 1

[0044]

[0045] Synthesis of intermediate M001-1:

[0046] Weigh 3,6-dimethylcarbazole (21.48g, 110mmol, C1), 2-fluoro-4-chlorobromobenzene (38.0g, 100mmol, C2), cesium carbonate (39.1g, 120mmol) in a flask, add 300mL dry N,N-dimethylformamide, and purify. Under nitrogen protection, react at 140℃ for 6h. Stop the reaction, cool to room temperature, pour into 600ml water, precipitate solid, and filter. Collect the solid, separate and purify with silica gel column to obtain 32.34g product with a yield of 84%. The molecular weight measured by mass spectrometry is m / z=384.9 (M+H) + ;

[0047] Synthesis of intermediate M001-2:

[0048] Weigh the intermediate M001-1 (30.52g, 80mmol) and dissolve it in 300mL of anhydrous THF, and stir at -78℃ for 20 minutes. Under nitrogen protection, add n-butyl lithium in n-hexane solution (38.4mL, 96mmol, 2.5M) to the reaction solution. After the addition is complete, keep stirring at low temperature for 1h. At -78℃, weigh 9-fluorenone (17.28g, 96mmol, C3) and add it to the reaction solution, return to room temperature naturally, and react for 10h. Add 100mL of water to quench the reaction, extract with ethyl acetate / water three times, collect the organic phase, remove the solvent by rotary evaporation, and separate with silica gel column to obtain the crude product. Dissolve the crude product in 200mL of dichloromethane, stir at room temperature, add boron trifluoride ether (9.6mL, 80mmol) dropwise under nitrogen protection, and stir at room temperature for 1h. Stop the reaction, add sodium carbonate solution to neutralize the reaction solution, and extract with dichloromethane three times. The solvent was removed by rotary evaporation and separated by silica gel column to obtain 29.15 g of intermediate M2 with a yield of 78%. The molecular weight measured by mass spectrometry was m / z=467.2 (M+H) + ;

[0049] Synthesis of intermediate M001-3:

[0050] Weigh the intermediate M001-2 (28.03g, 60mmol), 4-tert-butylaniline (10.73g, 72mmol, C4), tris(dibenzylideneacetone)dipalladium (1.66g, 1.8mmol), 2-dicyclohexylphosphine-2',6'-dimethoxy-1,1'-biphenyl (1.48g, 3.6mmol, S-Phos), and sodium tert-butoxide (11.52g, 120mmol) in a flask, and add 300mL toluene and ventilate. Under nitrogen protection, reflux at 110°C for 20h. Stop the reaction, cool to room temperature, extract with ethyl acetate and water, and concentrate by rotary evaporation. Then separate and purify with a silica gel column to obtain about 30.29g of product with a yield of 87%. The molecular weight measured by mass spectrometry is m / z=580.3 (M+H) + ;

[0051] Synthesis of intermediate M001-4:

[0052] Weigh the intermediate M001-3 (29.15g, 50mmol), 1-bromo-5-(tert-butyl)-2,3-dichlorobenzene (14.1g, 50mmol, C5), tris(dibenzylideneacetone)dipalladium (1.66g, 1.5mmol), 2-dicyclohexylphosphine-2',4',6'-triisopropylbiphenyl (1.43g, 3.0mmol, X-Phos), and sodium tert-butoxide (96.10g, 100mmol) in a flask, and add 300mL toluene and ventilate. Under nitrogen protection, reflux at 110°C for 12h. Stop the reaction, cool to room temperature, extract with ethyl acetate and water, and concentrate by rotary evaporation. Then separate and purify with a silica gel column to obtain about 32.05g of product with a yield of 82%. The molecular weight measured by mass spectrometry is m / z=781.8 (M+H) + ;

[0053] Synthesis of intermediate M001-5:

[0054] Weigh the intermediate M001-4 (31.26g, 40mmol), 4-tert-butylaniline (7.15g, 48mmol, C4), tris(dibenzylideneacetone)dipalladium (1.48g, 1.6mmol), 2-dicyclohexylphosphine-2',6'-dimethoxy-1,1'-biphenyl (1.32g, 3.2mmol, S-Phos), and sodium tert-butoxide (7.68g, 80mmol) in a flask, and add 200mL of xylene and purify. Under nitrogen protection, reflux at 140°C for 20h. Stop the reaction, cool to room temperature, extract with ethyl acetate and water, and concentrate by rotary evaporation. Then separate and purify with a silica gel column to obtain about 27.2g of product with a yield of 76%. The molecular weight measured by mass spectrometry is m / z=894.8 (M+H) + ;

[0055] Synthesis of intermediate M001-6:

[0056] Weigh the intermediate M001-5 (26.84g, 30mmol), 3-bromo-5-(tert-butyl)benzo[B]thiophene (9.69g, 36mmol, C6), tri(dibenzylideneacetone)dipalladium (1.66g, 1.5mmol), tri-tert-butylphosphine (6.97g, 3.0mmol), and sodium tert-butoxide (57.66g, 60mmol) in a flask, and add 200mL toluene and ventilate. Under nitrogen protection, reflux at 110°C for 12h. Stop the reaction, cool to room temperature, extract with ethyl acetate and water, and concentrate by rotary evaporation. Then separate and purify with a silica gel column to obtain about 23.72g of product with a yield of 73%. The molecular weight measured by mass spectrometry is m / z=1082.9 (M+H) + ;

[0057] Synthesis of product BD001:

[0058] Weigh the intermediate M001-6 (21.66 g, 20 mmol) and dissolve it in 100 mL of dry xylene. Protect with nitrogen. Add tert-butyl lithium solution (15.4 mL, 30 mmol, 1.3 M) dropwise at -20 ° C, stir at low temperature for 1 hour, and stir at 60 ° C for 1 hour. Return to -20 ° C, add boron tribromide (10.0 g, 40 mmol), stir at low temperature for 1 hour, and stir at room temperature for 2 hours. Add diisopropylethylamine (7.68 g, 60 mmol), heat to 110 ° C and react for 6 hours. Stop the reaction, cool to room temperature, add sodium carbonate solution to neutralize to neutrality, extract with dichloromethane three times, collect the organic phase, spin dry the solvent, separate on a silica gel column, and obtain 3.38 g of yellow solid with a yield of 16%. The molecular weight measured by mass spectrometry is m / z=1041.5 (M+H) + ;

[0059] Synthesis Example 2

[0060]

[0061] The synthesis conditions of product BD004 are the same as those of product BD001, except that C1 is replaced by C7; the molecular weight measured by liquid chromatography mass spectrometry is m / z=1140.6 (M+H) + .

[0062] Synthesis Example 3

[0063]

[0064] The synthesis conditions of product BD005 are the same as those of product BD001, except that C8 replaces C1; the molecular weight measured by liquid chromatography-mass spectrometry is m / z=1256.7 (M+H) + .

[0065] Synthesis Example 4

[0066]

[0067] The synthesis conditions of product BD010 are the same as those of product BD001, except that C1 is replaced by C9; the molecular weight measured by liquid chromatography mass spectrometry is m / z=1208.6 (M+H) + .

[0068] Synthesis Example 5

[0069]

[0070] The synthesis conditions of product BD013 are the same as those of product BD001, except that C1 is replaced by C10; the molecular weight measured by liquid chromatography mass spectrometry is m / z=1280.6 (M+H) + .

[0071] Synthesis Example 6

[0072]

[0073] The synthesis conditions of product BD018 are the same as those of product BD001, except that C1 is replaced by C11; the molecular weight measured by liquid chromatography mass spectrometry is m / z=1460.6 (M+H) + .

[0074] Synthesis Example 7

[0075]

[0076] The synthesis conditions of product BD019 are the same as those of product BD001, except that C1 is replaced by C12; the molecular weight measured by liquid chromatography mass spectrometry is m / z=1160.6 (M+H) + .

[0077] Synthesis Example 8

[0078]

[0079] The synthesis conditions of product BD024 are the same as those of product BD001, except that C1 is replaced by C13; the molecular weight measured by liquid chromatography mass spectrometry is m / z=1162.6 (M+H) + .

[0080] Synthesis Example 9

[0081]

[0082] The synthesis conditions of product BD029 are the same as those of product BD001, except that C1 is replaced by C14; the molecular weight measured by liquid chromatography mass spectrometry is m / z=1132.6 (M+H) + .

[0083] Synthesis Example 10

[0084]

[0085] The synthesis conditions of product BD033 are the same as those of product BD001, except that C1 is replaced by C15; the molecular weight measured by liquid chromatography mass spectrometry is m / z=1220.6 (M+H) + .

[0086] Synthesis Example 11

[0087]

[0088] The synthesis conditions of product BD036 are the same as those of product BD001, except that C1 is replaced by C16; the molecular weight measured by liquid chromatography mass spectrometry is m / z=1195.6 (M+H) + .

[0089] Synthesis Example 12

[0090]

[0091] The synthesis conditions of product BD038 are the same as those of product BD001, except that C1 is replaced by C17; the molecular weight measured by liquid chromatography-mass spectrometry is m / z=1118.5 (M+H) + .

[0092] Synthesis Example 13

[0093]

[0094] The synthesis conditions of product BD041 are the same as those of product BD010, except that C18 replaces C5; the molecular weight measured by liquid chromatography-mass spectrometry is m / z=1166.6 (M+H) + .

[0095] Synthesis Example 14

[0096]

[0097] The synthesis conditions of product BD033 are the same as those of product BD001, except that C1 is replaced by C19 and C5 is replaced by C20; the molecular weight measured by liquid chromatography mass spectrometry is m / z=1230.7 (M+H) + .

[0098] Synthesis Example 15

[0099]

[0100] The synthesis conditions of product BD052 are the same as those of product BD004, except that C21 replaces C5; the molecular weight measured by liquid chromatography mass spectrometry is m / z=1218.7 (M+H) + .

[0101] Synthesis Example 16

[0102]

[0103] The synthesis conditions of product BD058 are the same as those of product BD004, except that C22 replaces C5; the molecular weight measured by liquid chromatography mass spectrometry is m / z=1218.6 (M+H) + .

[0104] Synthesis Example 17

[0105]

[0106] The synthesis conditions of product BD063 are the same as those of product BD001, except that C23 replaces C1 and C24 replaces C3; the molecular weight measured by liquid chromatography mass spectrometry is m / z=1160.6 (M+H) + .

[0107] Synthesis Example 18

[0108]

[0109] The synthesis conditions of product BD069 are the same as those of product BD001, except that C25 replaces C1 and C26 replaces C3; the molecular weight measured by liquid chromatography mass spectrometry is m / z=1200.6 (M+H) + .

[0110] Synthesis Example 19

[0111]

[0112] The synthesis conditions of product BD076 are the same as those of product BD004, except that one of the C4 is replaced by C27; the molecular weight measured by liquid chromatography mass spectrometry is m / z=1140.6 (M+H) + .

[0113] Synthesis Example 20

[0114]

[0115] The synthesis conditions of product BD082 are the same as those of product BD004, except that C27 replaces C4; the molecular weight measured by liquid chromatography mass spectrometry is m / z=1140.6 (M+H) + .

[0116] Synthesis Example 21

[0117]

[0118] The synthesis conditions of product BD092 are the same as those of product BD058, except that one of the C4 is replaced by C28; the molecular weight measured by liquid chromatography mass spectrometry is m / z=1272.7 (M+H) + .

[0119] Synthesis Example 22

[0120]

[0121] The synthesis conditions of product BD102 are the same as those of product BD001, except that C19 replaces C1, and C28 replaces C4; the molecular weight measured by liquid chromatography mass spectrometry is m / z=1324.8 (M+H) + .

[0122] Synthesis Example 23

[0123]

[0124] The synthesis conditions of product BD106 are the same as those of product BD082, except that C29 replaces C7; the molecular weight measured by liquid chromatography mass spectrometry is m / z=1180.6 (M+H) + .

[0125] Synthesis Example 24

[0126]

[0127] The synthesis conditions of product BD112 are the same as those of product BD004, except that C30 replaces C6; the molecular weight measured by liquid chromatography-mass spectrometry is m / z=1174.6 (M+H) + .

[0128] Synthesis Example 25

[0129]

[0130] The synthesis conditions of product BD124 are the same as those of product BD004, except that one of C4 is replaced by C28, and C6 is replaced by C31. The molecular weight measured by liquid chromatography mass spectrometry is m / z=1248.7 (M+H). + .

[0131] Synthesis Example 26

[0132]

[0133] The synthesis conditions of product BD004 are the same as those of product BD004, except that one of the C4 is replaced by C32; the molecular weight measured by liquid chromatography mass spectrometry is m / z=1216.7 (M+H) + .

[0134] Synthesis Example 27

[0135]

[0136] The synthesis conditions of product BD134 are the same as those of product BD004, except that one of the C4 is replaced by C33; the molecular weight measured by liquid chromatography mass spectrometry is m / z=1174.6 (M+H) + .

[0137] Synthesis Example 28

[0138]

[0139] The synthesis conditions of product BD137 are the same as those of product BD004, except that C34 replaces C33; the molecular weight measured by liquid chromatography mass spectrometry is m / z=1110.5 (M+H) + .

[0140] Synthesis Example 29

[0141]

[0142] The synthesis conditions of product BD140 are the same as those of product BD082, except that 35 replaces C5 and C36 replaces 6; the molecular weight measured by liquid chromatography-mass spectrometry is m / z=1105.5 (M+H) + .

[0143] Synthesis Example 30

[0144]

[0145] The synthesis conditions of product BD150 are the same as those of product BD076, except that C19 replaces C7 and C37 replaces C5; the molecular weight measured by liquid chromatography-mass spectrometry is m / z=1225.8 (M+H) + .

[0146] Synthesis Example 31

[0147]

[0148] The synthesis conditions of product BD151 are the same as those of product BD005, except that C38 replaces C2, C39 replaces C5, and C40 replaces C6; the molecular weight measured by liquid chromatography mass spectrometry is m / z=1272.8 (M+H) + .

[0149] Synthesis Example 32

[0150]

[0151] The synthesis conditions of product BD158 are the same as those of product BD004, except that C41 replaces C7, C42 replaces C2, C43 replaces C3, C44 replaces C4, C45 replaces C5, and C46 replaces C6; the molecular weight measured by liquid chromatography mass spectrometry is m / z=1238.8 (M+H) + .

[0152] Device Example: Fabrication of Organic Electroluminescent Devices Used as Light Emitting Materials

[0153] A 50 mm × 50 mm × 0.7 mm thick glass substrate with an indium tin oxide / silver / indium tin oxide (ITO / Ag / ITO) anode was ultrasonically cleaned in isopropyl alcohol for 5 minutes. The cleaned glass substrate was mounted on a substrate rack of a vacuum evaporation device and evacuated to 1×10 -5 ~1×10 -6 Pa, before evaporating the organic material, treat with nitrogen plasma for 120 seconds. Then co-evaporate HT and PD as a doped hole injection layer (HIL) on the anode, with a film thickness of 10nm, where the doping concentration of PD is 3%. Evaporate HT on the hole injection layer as a hole transport layer (HTL) with a film thickness of 132nm. Then, evaporate EB on the hole transport layer as an electron blocking layer (EBL) with a film thickness of 5nm. Then, co-evaporate the light-emitting layer (EML) on the electron blocking layer with a film thickness of 20nm; the light-emitting layer (EML) adopts a multi-source co-evaporation method to evaporate the main material and the light-emitting material (BH and BD001) of the light-emitting layer, where the doping concentration of the light-emitting material is 1.5%. Then evaporate HB on the light-emitting layer as a hole blocking layer (HBL) with a film thickness of 5nm. Then on the hole blocking layer, 1:1 co-evaporate the electron transport material (ET) and 8-hydroxyquinoline lithium (Liq) as the electron transport layer (ETL), with a film thickness of 30nm. In addition, LiF was evaporated on the ETL as an electron injection layer (EIL) with a thickness of 1 nm. Then, cathode metal magnesium / silver (Mg / Ag) was co-evaporated on the EIL with a thickness of 13.2 nm, wherein the doping concentration of magnesium was 10%. Finally, CP was evaporated as a light coupling layer (CPL) with a thickness of 70 nm. The fabricated device was transferred to a glove box and encapsulated with a glass cover. The structure of the organic electroluminescent device of Example 1 is shown in FIG. Figure 1 As shown, Figure 1 The stacking order and role of each functional layer are also shown.

[0154] The OLED has the following layer structure in principle: ITO / Ag / ITO substrate / hole injection layer (HIL) / hole transport layer (HTL) / electron blocking layer (EBL) / luminescent layer (EML) / hole blocking layer (HBL) / electron transport layer (ETL) / electron injection layer (EIL) / cathode / coupling layer (CPL). The exact structure of the OLED is shown in Table 1.

[0155] Table 1 Materials used for OLED

[0156]

[0157] manual

[0158]

[0159] Device Example 1 :

[0160] ITO / Ag / ITO / HT:PD(10nm,3%) / HT(132nm) / EB(5nm) / BH:BD001(20nm,1.5%) / HB(5nm) / ET:Liq(30nm,50%) / LiF(1nm) / Ag:Mg(13.2nm,10%) / CP(70nm)

[0161] The only difference between device example 2-32 and device example 1 is that BD001 of the present invention used in the light-emitting layer is replaced with other compounds of the present invention. The obtained device performance test data is shown in Table 2.

[0162] Device Comparison Examples 1 to 4 :

[0163] Compared with device embodiment 1, the difference between this comparative example is that BD001 in the organic electroluminescent device is changed to Ref-1, Ref-2, Ref-3, and Ref-4 which are well-known in the industry and have been commercially applied. The obtained device performance test data are shown in Table 2.

[0164] The OLEDs were characterized by standard methods. For this purpose, the electroluminescence spectrum, half-peak width, current efficiency (measured in cd / A), power efficiency (measured in lm / W) and external quantum efficiency (EQE, measured in %) and color coordinates (CIEx, CIEy) were determined, which were calculated as a function of the luminous density from the current / voltage / luminous density characteristic line (IUL characteristic line) exhibiting Lambertian emission characteristics. The blue light index (BI) is expressed at 10 mA / cm 2 Current efficiency / CIEy under T95, which means the device is at 20mA / cm 2 The FWHM value indicates the working time of the device when the brightness decreases to 95% at the initial brightness of 10mA / cm 2 The device performances of Examples 1 to 32 of the present invention and Comparative Examples 1 to 4 are summarized in Table 2;

[0165] Table 2 Device performance

[0166]

[0167]

[0168] As can be seen from Table 2, compared with the prior art, the use of material embodiments 1-32 of the present invention has good performance in spectrum narrowing, efficiency and life improvement. Compared with Comparative Example 2, the FWHM of BD082 of device embodiment 20 is narrowed by 1nm, the efficiency is improved by 10.3%, and the life is also improved by 28%; the performance improvement comes from the large plane of indole acridine, which can increase the rigidity of the molecule, improve the radiation rate and stability. Compared with Comparative Example 3, the FWHM of BD010 of device embodiment 4 is narrowed by 0.7nm, the efficiency is improved by 5.9%, and the life is also improved by 9.4%. The performance improvement comes from the greater conjugation of indole acridine relative to indole; at the same time, after the hydrogen on the carbazole part is replaced, aggregation can be inhibited; thereby improving efficiency and life. Compared with Comparative Example 4, the FWHM of BD004 of device embodiment 2 is slightly narrowed, but the efficiency is improved by 14.6%, and the life is also improved by 7.8%. The performance improvement comes from the spectrum and energy level that better match the device. Molecular deuteration can also improve the device lifespan to a certain extent. For example, the device embodiment 31 has a lifespan increased by 13.6% compared to device 3. This is because the deuterium atom has a shorter bond length than the hydrogen atom and is more stable.

Claims

1. A fused heterocyclic compound, characterized in that: The fused heterocyclic compound is represented by the following general formula (1): R1 represents hydrogen, substituted or unsubstituted alkyl, substituted or unsubstituted silyl; R2 to R6 independently represent hydrogen, substituted or unsubstituted alkyl, substituted or unsubstituted silyl, substituted or unsubstituted aryl, substituted or unsubstituted heteroaryl, substituted or unsubstituted diphenylamino, and adjacent groups may form a ring; a, b, c, d, e are independently 0 to 4; Ar1 and Ar2 each independently represent a substituted or unsubstituted aryl group, or a substituted or unsubstituted heteroaryl group; The entire molecule may be deuterated or undeuterated.

2. The fused heterocyclic compound for an organic electroluminescent device according to claim 1, characterized in that: The R1 represents a substituted or unsubstituted alkyl group having 1 to 6 carbon atoms.

3. The fused heterocyclic compound for an organic electroluminescent device according to claim 1, characterized in that: The R2 to R6 represent a substituted or unsubstituted alkyl group having 1 to 6 carbon atoms or a substituted or unsubstituted phenyl group.

4. The fused heterocyclic compound for an organic electroluminescent device according to claim 1, characterized in that: The Ar1 and Ar2 each independently represent a substituted or unsubstituted phenyl group.

5. The fused heterocyclic compound for an organic electroluminescent device according to claim 1, characterized in that: The "substituted" in the "substituted or unsubstituted" in the compound means that the substituent is independently selected from a deuterium atom, a tritium atom, a halogen atom, a cyano group, a nitro group, a hydroxyl group, a monovalent alkyl group or a cycloalkyl group having 1 to 10 carbon atoms, a monovalent monocyclic aromatic group or a condensed aromatic group having 6 to 30 carbon atoms, and a monovalent heterocyclic group or a condensed heteroaryl group having 2 to 50 carbon atoms.

6. The fused heterocyclic compound for an organic electroluminescent device according to claim 1, characterized in that: The fused heterocyclic compound is selected from the following structures:

7. An organic electroluminescent device, characterized in that: The organic electroluminescent device comprises an anode, a cathode and at least one organic thin film between the anode and the cathode, wherein the organic thin film contains the compound according to any one of claims 1 to 6.

8. The organic electroluminescent device according to claim 7, characterized in that: The compound is used as a light-emitting material in an organic electroluminescent device.

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