Bis-carbazolo pyrene compound and organic electroluminescent device containing same

Abstract

The invention provides a dicarbazolo pyrene compound for an organic light-emitting device and the organic light-emitting device containing the dicarbazolo pyrene compound. Wherein the dicarbazolo pyrene structure has very strong rigidity and can effectively inhibit non-radiation vibration, so that the efficiency of the device is improved. Moreover, steric hindrance groups such as diarylamine or tertiary butyl are connected to the periphery of the dicarbazolo pyrene structure, so that aggregation can be effectively inhibited, and the service life of the device is prolonged; and meanwhile, the service life of the device is prolonged due to the relatively shallow HOMO / LUMO energy level.

Description

Technical Field

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

[0002] The luminescent materials of the organic light-emitting diode (OLED) panel are composed of red, green and blue. High-performance and high-color-purity luminescent materials can enable OLED panels to have better color reproduction and brightness. Red light is affected by the "energy gap rule". At the same time, the commercial red light material is a phosphorescent material, which will have a large efficiency roll-off. Therefore, there is a lot of room for improvement in the efficiency of red light materials. The main way to improve efficiency is to increase the utilization and stability of triplet excitons. Traditional phosphorescent materials have a relatively large triplet exciton concentration and a relatively low radiation rate, which leads to a serious roll-off of material efficiency, affecting device efficiency. In addition, phosphorescent materials have a relatively high half-width, which makes it difficult to achieve deep red light or high-efficiency deep red light emission.

[0003] Therefore, how to achieve high-efficiency red light has become one of the focuses of OLED research. Summary of the invention

[0004] In order to solve the above technical problems, the present invention provides: 1) a biscarbazopyrene compound for an organic electroluminescent device, wherein the compound is represented by formula (1) to formula (8):

[0005]

[0006] wherein a and b are each an integer from 1 to 7, such as 1, 2, 3, 4, 5, 6, 7, and r is an integer from 1 to 6, such as 1, 2, 3, 4, 5, 6;

[0007] When there are multiple R1 and R2, the multiple R1 and R2 may be the same or different;

[0008] The R1 and R2 are selected from hydrogen, fluorine, substituted or unsubstituted alkyl having 1 to 50 carbon atoms, substituted or unsubstituted cycloalkyl having 3 to 50 ring carbon atoms, substituted or unsubstituted aryl having 6 to 50 ring carbon atoms, substituted or unsubstituted arylamine having 6 to 50 ring carbon atoms, substituted or unsubstituted monovalent heterocyclic group having 5 to 50 ring atoms, and substituted or unsubstituted silyl.

[0009] 2) According to the biscarbazole pyrene 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.

[0010] 3) According to the biscarbazole pyrene compound for organic electroluminescent devices described in 1) or 2) above, wherein R1 and R2 are selected from hydrogen, fluorine, substituted or unsubstituted alkyl having 1 to 20 carbon atoms, substituted or unsubstituted cycloalkyl having 3 to 8 ring carbon atoms, substituted or unsubstituted aryl having 6 to 10 ring carbon atoms, substituted or unsubstituted diphenylamine, substituted or unsubstituted monovalent heterocyclic group having 5 to 10 ring atoms, and substituted or unsubstituted silyl.

[0011] 4) The biscarbazopyrene compound for an organic electroluminescent device according to 1) or 2) above, wherein R1 and R2 are selected from hydrogen, a substituted or unsubstituted alkyl group having 1 to 6 carbon atoms, and a substituted or unsubstituted diphenylamine group.

[0012] 5) The biscarbazole pyrene compound for an organic electroluminescent device according to 1 above, characterized in that the biscarbazole pyrene compound is selected from the following structures:

[0013]

[0014]

[0015]

[0016]

[0017]

[0018]

[0019]

[0020]

[0021]

[0022]

[0023]

[0024]

[0025] 6) An organic electroluminescent device, wherein the organic electroluminescent device comprises an anode, a cathode and at least one organic thin film between the anode and the cathode, and the organic thin film contains the compound described in any one of 1) to 5) above.

[0026] 7) The organic electroluminescent device according to 6) above, wherein the compound is used as a light-emitting material in the organic electroluminescent device.

[0027] The beneficial effects of the present invention include: the biscarbazopyrene structure in the invention has strong rigidity and can effectively suppress non-radiative vibration, thereby improving the efficiency of the device. Moreover, by connecting steric groups such as diarylamine or tert-butyl to the periphery of the biscarbazopyrene structure, aggregation can be effectively suppressed and the device life can be improved; at the same time, its shallow HOMO / LUMO energy level increases the device life. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] 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:

[0029] Figure 1 This 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:

[0030] 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 DESCRIPTION

[0031] the term

[0032] 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.

[0033] The cycloalkyl group may be a monocyclic ring or a condensed ring. Specific examples include cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, cycloheptyl, and adamantyl, and preferably cyclohexyl is used.

[0034] The aryl group can be a monocyclic or polycyclic aryl group. 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, naphthacene, fluorenyl, acenaphthenyl, triphenylene and fluoranthenyl, but the scope of the present invention is not limited thereto.

[0035] The arylamine group is an amine group substituted with an aryl group. Examples of arylamine groups include substituted or unsubstituted monoarylamine groups, substituted or unsubstituted diarylamine groups, and substituted or unsubstituted triarylamine groups. The aryl group in the arylamine group can be a monocyclic or polycyclic aryl group. The arylamine group can contain two or more aryl groups. In this case, the aryl group can be a monocyclic aryl group or a polycyclic aryl group. Alternatively, the aryl group can be composed of a monocyclic aryl group and a polycyclic aryl group. The aryl group in the arylamine group can be selected from those exemplified above. Specific examples of the arylamino group include phenylamino, naphthylamino, biphenylamino, anthracenylamino, diphenylamino, N-phenylnaphthylamino, xylylamino, N-phenyltolylamino, N-phenylbiphenylamino, N-phenylnaphthylamino, N-biphenylnaphthylamino, N-naphthylfluorenylamino, N-phenylphenanthrenylamino, N-biphenylphenanthrenylamino, N-phenylfluorenylamino, N-phenylterphenylamino, N-phenanthrenylfluorenylamino, and N-biphenylfluorenylamino.

[0036] "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.

[0037] 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.

[0038] Preferably, the "substituted" group in "substituted or unsubstituted" is independently selected from any one or more of the following groups: deuterium atom, tritium atom, halogen atom, cyano group, nitro group, hydroxyl group, methyl group, methoxy group, ethyl group, n-propyl group, isopropyl group, n-butyl group, isobutyl group, sec-butyl group, tert-butyl group, 2-methylbutyl group, cyclohexyl group, adamantyl group, 2-ethylhexyl group, trifluoromethyl group, pentafluoroethyl group, 2,2,2-trifluoroethyl group, phenyl group, deuterated benzene group phenyl, fluorophenyl, methylphenyl, n-propylphenyl, tert-butylphenyl, trimethylphenyl, triphenylphenyl, tetraphenylphenyl, cyanophenyl, pyridyl, naphthyl, anthracenyl, biphenyl, diphenyl, terphenyl, fluorenyl, spirobifluorenyl, furanyl, benzofuranyl, dibenzofuranyl, azadibenzofuranyl, thienyl, benzothienyl, dibenzothienyl, azadibenzothienyl, carbazolyl, phenylcarbazolyl, azacarbazolyl.

[0039] The principles and features of the present invention will be further illustrated below by taking a number of synthesis examples and device examples as examples. The examples cited are only used to explain the present invention, but are not used to limit the scope of the present invention. In addition, the isotopic types of hydrogen atoms present in the molecules of the compounds used in the present invention are not particularly limited. For example, all hydrogen atoms in the molecules can be 1 H, or part or all of it 2 H (deuterium D).

[0040] Synthesis Example 1: Synthesis of FRD001

[0041] Synthesis of intermediate 1-1

[0042]

[0043] Diphenylamine (RM-1, 8.45g, 50mmol), 2-bromo-1-chloro-4-iodobenzene (15.80g, 50mmol), tri(dibenzylideneacetone)dipalladium (0.93g, 1.0mmol), sodium tert-butoxide (7.20g, 75mmol). The reaction system was ventilated three times and protected by nitrogen. Then, a toluene solution (1mol / L) of tri-tert-butylphosphine and 200mL of toluene were added with a syringe (4.0mL, 4.0mmol). Under nitrogen protection, heat and stir, and react at 105°C for 12h. Stop the reaction, cool to room temperature, add 200mL of deionized water, and transfer the reaction solution to a separatory funnel for extraction and separation. The extract was dried over anhydrous magnesium sulfate and concentrated, and the sample was purified by silica gel column chromatography to obtain intermediate 1-1, 17.85g, with a yield of 88%; the molecular weight measured by liquid chromatography-mass spectrometry was m / z=358;

[0044] Synthesis of intermediate 1-2:

[0045]

[0046] Add intermediate 1-1 (14.32 g, 40 mmol), o-nitrobenzeneboric acid (6.68 g, 40 mmol), 100 mL of toluene, 20 mL of ethanol and 50 mL of 2M potassium carbonate aqueous solution into a 250 mL round-bottom flask and stir to dissolve. The reaction system was ventilated three times, and tetrakis(triphenylphosphine)palladium (1.78 g, 1.6 mmol) was added under nitrogen protection. Under nitrogen protection, heated and stirred, refluxed at 110°C for 12 h. Stop the reaction, cool to room temperature, add 100 ml of deionized water, and transfer the reaction solution to a separatory funnel for extraction and separation. The extract was dried over anhydrous magnesium sulfate and concentrated, and the sample was purified by silica gel column chromatography to obtain intermediate 1-2, 12.07 g, with a yield of 78%; the molecular weight measured by liquid chromatography-mass spectrometry was m / z=387;

[0047] Synthesis of intermediate 1-3:

[0048]

[0049] Add intermediate 1-2 (11.61 g, 30 mmol), triphenylphosphine (19.67 g, 75 mmol), and 100 mL of dichlorobenzene to a 250 mL round-bottom flask, stir to dissolve, and ventilate the reaction system three times. Under nitrogen protection, heat and stir, and react at 170 ° C for 12 hours. Stop the reaction, cool to room temperature, and remove dichlorobenzene by reduced pressure evaporation. Then add 100 ml of deionized water and 100 mL of ethyl acetate, and transfer the reaction solution to a separatory funnel for extraction and separation. The extract was dried over anhydrous magnesium sulfate and concentrated, and the sample was purified by silica gel column chromatography to obtain intermediate 1-3, 9.50 g, with a yield of 86%; the molecular weight measured by liquid chromatography-mass spectrometry was m / z = 368;

[0050] Synthesis of intermediate 1-4:

[0051]

[0052] Add intermediate 1-3 (9.20g, 25mmol), 1,1'-bis(diphenylphosphino)ferrocenepalladium dichloride (0.37g, 0.5mmol), bis(pinacol)diboron (8.89g, 35mmol), potassium acetate (9.80g, 100mmol) and 150ml anhydrous N, N-dimethylformamide to a 250mL round-bottom flask, stir, and ventilate the reaction system three times. Under nitrogen protection, heat and stir, react at 80°C for 12h. Stop the reaction, cool to room temperature, and remove N, N-dimethylformamide by reduced pressure evaporation. Then add 100ml deionized water and 100mL ethyl acetate, and transfer the reaction solution to a separatory funnel for extraction and separation. The extract is dried and concentrated with anhydrous magnesium sulfate, and the sample is purified by silica gel column chromatography to obtain intermediate 1-4, 9.50g, with a yield of 86%; the molecular weight measured by liquid phase mass spectrometry is m / z=368;

[0053] Synthesis of intermediate 1-5:

[0054]

[0055] Add intermediate 1-4 (7.36 g, 20 mmol), 3,8-dibromo-4,9-diiodopyrene (RM-2, 6.10 g, 10 mmol), 100 mL of toluene and 30 mL of 2M potassium carbonate aqueous solution to a 250 mL round-bottom flask and stir to dissolve. The reaction system was ventilated three times, and tetrakis(triphenylphosphine)palladium (0.89 g, 0.8 mmol) was added under nitrogen protection. Under nitrogen protection, heated and stirred, refluxed at 110°C for 12 h. Stop the reaction, cool to room temperature, add 100 ml of deionized water, and transfer the reaction solution to a separatory funnel for extraction and separation. The extract was dried over anhydrous magnesium sulfate and concentrated, and the sample was purified by silica gel column chromatography to obtain intermediate 1-5, 7.77 g, with a yield of 76%; the molecular weight measured by liquid phase mass spectrometry was m / z=1022;

[0056] FRD001 Synthesis:

[0057]

[0058] Under nitrogen atmosphere, intermediate 1-5 (7.15 g, 7.0 mmol) was dissolved in 50 mL of anhydrous N, N-dimethylformamide, and then tetrabutylammonium hydroxide (9.10 g, 35 mmol, 40% in methanol) was added, and finally cuprous iodide (2.66 g, 14.0 mmol) was added. The reaction was carried out at 120°C for 24 h. The reaction was stopped, cooled to room temperature, 100 ml of deionized water and ethyl acetate were added, and the reaction solution was transferred to a separatory funnel and extracted and separated. The extract was dried over anhydrous magnesium sulfate and concentrated, and the sample was purified by silica gel column chromatography to obtain the product FRD001, 3.38 g, with a yield of 56%; the molecular weight measured by liquid phase mass spectrometry was m / z=863;

[0059] Table 1

[0060]

[0061]

[0062]

[0063]

[0064] Synthesis Example 27: Synthesis of FRD159

[0065] Synthesis of intermediate 159-1:

[0066]

[0067] 1-Bromocarbazole (RM-3, 7.35g, 30mmol), 1,1'-bis(diphenylphosphinoferrocene)palladium dichloride (0.44g, 0.6mmol), bis(pinacol)diboron (10.16g, 40mmol), potassium acetate (11.76g, 120mmol) and 150ml of anhydrous N, N-dimethylformamide were added to a 250mL round-bottom flask, stirred, and the reaction system was vented three times. Under nitrogen protection, heated and stirred, reacted at 80°C for 12h. Stop the reaction, cool to room temperature, and remove N, N-dimethylformamide by reduced pressure evaporation. Then add 100ml of deionized water and 100mL of ethyl acetate, and transfer the reaction solution to a separatory funnel for extraction and separation. The extract was dried over anhydrous magnesium sulfate and concentrated, and the sample was purified by silica gel column chromatography to obtain intermediate 159-1, 7.82 g, with a yield of 89%; the molecular weight measured by liquid chromatography-mass spectrometry was m / z = 293;

[0068] Synthesis of intermediate 159-2:

[0069]

[0070] Add intermediate 159-1 (7.32 g, 25 mmol), 1,6-diisopropyl-3,8-dibromo-4,9-diiodopyrene (RM-4, 8.69 g, 12.5 mmol), 100 mL of toluene and 30 mL of 2M potassium carbonate aqueous solution into a 250 mL round-bottom flask and stir to dissolve. The reaction system was ventilated three times, and tetrakis(triphenylphosphine)palladium (1.12 g, 1.0 mmol) was added under nitrogen protection. Under nitrogen protection, heated and stirred, refluxed at 110°C for 12 h. Stop the reaction, cool to room temperature, add 100 ml of deionized water, and transfer the reaction solution to a separatory funnel for extraction and separation. The extract was dried over anhydrous magnesium sulfate and concentrated, and the sample was purified by silica gel column chromatography to obtain intermediate 159-2, 7.06 g, with a yield of 73%; the molecular weight measured by liquid chromatography-mass spectrometry was m / z=774;

[0071] FRD159 synthesis:

[0072]

[0073] Under nitrogen atmosphere, the intermediate 159-2 (6.19 g, 8.0 mmol) was dissolved in 50 mL of anhydrous N, N-dimethylformamide, and then tetrabutylammonium hydroxide (10.4 g, 40 mmol, 40% in methanol) was added, and finally cuprous iodide (3.04, 16.0 mmol) was added. The reaction was carried out at 120°C for 24 h. The reaction was stopped, cooled to room temperature, 100 ml of deionized water and ethyl acetate were added, and the reaction solution was transferred to a separatory funnel and extracted and separated. The extract was dried over anhydrous magnesium sulfate and concentrated, and the sample was purified by silica gel column chromatography to obtain the product FRD159, 3.30 g, with a yield of 54%; the molecular weight measured by liquid phase mass spectrometry was m / z=612;

[0074] Table 2

[0075]

[0076]

[0077] Synthesis Example 36: Synthesis of FRD193

[0078] Synthesis of intermediate 193-1:

[0079]

[0080] 1-Bromo-3,6-di-tert-butylcarbazole (RM-5, 10.74 g, 30 mmol), 1,1'-bis(diphenylphosphinoferrocene)palladium dichloride (0.37 g, 0.5 mmol), bis(pinacol)diboron (10.16 g, 40 mmol), potassium acetate (11.76 g, 120 mmol) and 150 ml of anhydrous N, N-dimethylformamide were added to a 250 ml round-bottom flask, stirred, and the reaction system was vented three times. Under nitrogen protection, heated and stirred, reacted at 80 ° C for 12 h. Stop the reaction, cool to room temperature, and remove N, N-dimethylformamide by reduced pressure evaporation. Then add 100 ml of deionized water and 100 ml of ethyl acetate, and transfer the reaction solution to a separatory funnel for extraction and separation. The extract was dried over anhydrous magnesium sulfate and concentrated, and the sample was purified by silica gel column chromatography to obtain intermediate 193-1, 11.30 g, with a yield of 93%; the molecular weight measured by liquid chromatography-mass spectrometry was m / z = 405;

[0081] Synthesis of intermediate 193-2:

[0082]

[0083] Add intermediate 193-1 (10.13 g, 25 mmol), 1,6-dichloro-3,8-dibromo-4,9-diiodopyrene (RM-6, 8.50 g, 12.5 mmol), 100 mL of toluene and 30 mL of 2M potassium carbonate aqueous solution into a 250 mL round-bottom flask and stir to dissolve. The reaction system was ventilated three times, and tetrakis(triphenylphosphine)palladium (1.12 g, 1.0 mmol) was added under nitrogen protection. Under nitrogen protection, heated and stirred, refluxed at 110°C for 12 h. Stop the reaction, cool to room temperature, add 100 ml of deionized water, and transfer the reaction solution to a separatory funnel for extraction and separation. The extract was dried over anhydrous magnesium sulfate and concentrated, and the sample was purified by silica gel column chromatography to obtain intermediate 159-2, 9.22 g, with a yield of 75%; the molecular weight measured by liquid chromatography-mass spectrometry was m / z=984;

[0084] Synthesis of intermediate 193-3:

[0085]

[0086] Under nitrogen atmosphere, the intermediate 193-2 (7.87 g, 8.0 mmol) was dissolved in 50 mL of anhydrous N, N-dimethylformamide, and then tetrabutylammonium hydroxide (10.4 g, 40 mmol, 40% in methanol) was added, and finally cuprous iodide (3.04, 16.0 mmol) was added. The reaction was carried out at 120°C for 24 h. The reaction was stopped, cooled to room temperature, 100 ml of deionized water and ethyl acetate were added, and the reaction solution was transferred to a separatory funnel and extracted and separated. The extract was dried over anhydrous magnesium sulfate and concentrated, and the sample was purified by silica gel column chromatography to obtain the intermediate 193-3, 3.42 g, with a yield of 52%; the molecular weight measured by liquid phase mass spectrometry was m / z=822;

[0087] Synthesis of FRD193:

[0088]

[0089] Diphenylamine (RM-1, 1.69 g, 10 mmol), intermediate 193-3 (3.28 g, 5 mmol), tris(dibenzylideneacetone)dipalladium (0.19 g, 0.2 mmol), sodium tert-butoxide (1.44 g, 15 mmol). The reaction system was ventilated three times and protected by nitrogen. Then, a toluene solution (1 mol / L) of tri-tert-butylphosphine and 100 ml of xylene were added with a syringe (0.8 mL, 0.8 mmol). Under nitrogen protection, the mixture was heated and stirred at 140°C for 12 h. The reaction was stopped, cooled to room temperature, 100 ml of deionized water was added, and the reaction solution was transferred to a separatory funnel for extraction and separation. The extract was dried over anhydrous magnesium sulfate and concentrated, and the sample was purified by silica gel column chromatography to obtain the product FRD193, 3.42 g, with a yield of 63%; the molecular weight measured by liquid chromatography-mass spectrometry was m / z=1087.

[0090] Table 3

[0091]

[0092]

[0093] Synthesis Example 47: Synthesis of FRD233

[0094] Synthesis of intermediate 233-1:

[0095]

[0096] 3,6-di-tert-butylcarbazole (RM-7, 8.37 g, 30 mmol), 1,6-diisopropyl-4,9-dibromo (14.65 g, 33 mmol), tri(dibenzylideneacetone)dipalladium (0.55 g, 0.6 mmol), sodium tert-butoxide (5.76 g, 60 mmol). The reaction system was ventilated three times and protected by nitrogen. Then, a toluene solution (1 mol / L) of tri-tert-butylphosphine and 100 ml of toluene were added with a syringe (2.4 mL, 2.4 mmol). Under nitrogen protection, heat and stir, and react at 105 ° C for 12 h. Stop the reaction, cool to room temperature, add 100 ml of deionized water, and transfer the reaction solution to a separatory funnel for extraction and separation. The extract was dried over anhydrous magnesium sulfate and concentrated, and the sample was purified by silica gel column chromatography to obtain intermediate 233-2, 16.0 g, with a yield of 83%; the molecular weight measured by liquid chromatography-mass spectrometry was m / z=642;

[0097] Synthesis of intermediate 233-2:

[0098]

[0099] Intermediate 233-1 (12.84 g, 20 mmol), 3,6-tert-butyldimethylsilylcarbazole (RM-9, 8.69 g, 22 mmol), tri(dibenzylideneacetone)dipalladium (0.37 g, 0.4 mmol), sodium tert-butoxide (3.84 g, 40 mmol). The reaction system was ventilated three times and protected by nitrogen. Then, a toluene solution (1.6 mL, 1.6 mmol) of tri-tert-butylphosphine and 100 ml of xylene were added with a syringe. Under nitrogen protection, heated and stirred, reacted at 115 ° C for 12 h. Stop the reaction, cool to room temperature, add 100 ml of deionized water, and transfer the reaction solution to a separatory funnel for extraction and separation. The extract was dried over anhydrous magnesium sulfate and concentrated, and the sample was purified by silica gel column chromatography to obtain intermediate 233-2, 14.55 g, with a yield of 76%; the molecular weight measured by liquid chromatography-mass spectrometry was m / z = 957;

[0100] Synthesis of intermediate 233-3:

[0101]

[0102] Dissolve the intermediate 233-2 (14.35 g, 15 mmol) in 100 mL of chloroform. At 0°C, add N-bromosuccinimide (NBS, 5.70 g, 32 mmol) in batches. Slowly warm to room temperature and react for 20 hours. Stop the reaction, add 100 ml of deionized water, and transfer the reaction solution to a separatory funnel for extraction and separation. Dry the extract with anhydrous magnesium sulfate and concentrate it, and purify the sample by silica gel column chromatography to obtain the product intermediate 233-3, 13.29 g, with a yield of 84%; the molecular weight measured by liquid chromatography-mass spectrometry is m / z=1055;

[0103] FRD233 synthesis:

[0104]

[0105] Intermediate 233-3 (10.55 g, 10 mmol), tri(dibenzylideneacetone)dipalladium (0.19 g, 0.2 mmol), sodium tert-butoxide (1.92 g, 20 mmol). The reaction system was ventilated three times and protected by nitrogen. Then, a toluene solution (1 mol / L) of tri-tert-butylphosphine and 50 ml of xylene were added with a syringe (0.8 mL, 0.8 mmol). Under nitrogen protection, the mixture was heated and stirred at 140°C for 12 h. The reaction was stopped, cooled to room temperature, 100 ml of deionized water was added, and the reaction solution was transferred to a separatory funnel for extraction and separation. The extract was dried over anhydrous magnesium sulfate and concentrated, and the sample was purified by silica gel column chromatography to obtain FRD233, 14.55 g, with a yield of 56%; the molecular weight measured by liquid chromatography-mass spectrometry was m / z=953.

[0106] Table 4

[0107]

[0108]

[0109] Device Example: Fabrication of an Organic Electroluminescent Device Using Red Light Emitting Layer Materials

[0110] A 50 mm × 50 mm × 0.7 mm thick glass substrate with an indium tin oxide (ITO) anode was ultrasonically cleaned in isopropyl alcohol for 5 minutes. The cleaned glass substrate was mounted on a substrate rack of a vacuum deposition 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 HI as a doping layer (HIL) on the anode, with a film thickness of 10nm, where the doping concentration of HI is 3%. Evaporate HT on the hole injection layer as a hole transport layer (HTL) with a film thickness of 140nm. Then, evaporate EB on the hole transport layer as an electron blocking layer (EBL) with a film thickness of 80nm. Then, co-evaporate the light-emitting layer (EML) on the electron blocking layer with a film thickness of 40nm; the light-emitting layer (EML) adopts a multi-source co-evaporation method to evaporate the main material, sensitizer and light-emitting material (RH, PRD and FRD001) of the light-emitting layer, where the doping concentration of the sensitizer is 5%, and the doping concentration of the light-emitting material is 0.5%. 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, an electron transport material (ET) and 8-hydroxyquinoline lithium (Liq) were co-deposited in a ratio of 1:1 as an electron transport layer (ETL) with a film thickness of 30 nm. In addition, LiF was evaporated on the ETL as an electron injection layer (EIL) with a film thickness of 1 nm. Then, metal aluminum (Al) was co-evaporated on the EIL with a film thickness of 100 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.

[0111] The OLED has in principle the following layer structure: ITO substrate / hole injection layer (HIL) / hole transport layer (HTL) / electron blocking layer (EBL) / emissive layer (EML) / hole blocking layer (HBL) / electron transport layer (ETL) / electron injection layer (EIL) / cathode. The exact structure of the OLED is shown in Table 5.

[0112] Table 5 Materials used for OLED

[0113]

[0114] Device Example 1:

[0115] ITO / HT:HI(10nm,3%) / HT(140nm) / EB(80nm) / RH:PRD:FRD001(40nm,5%,0.5%) / HB(5nm) / ET:Liq(30nm,50%) / LiF(1nm) / Al(100nm)

[0116] The only difference between device example 2-56 and device example 1 is that the FRD001 of the present invention used in the light-emitting layer is replaced by other compounds of the present invention. The performance test data of the obtained devices are shown in Table 5.

[0117] Comparative Examples 1 to 4:

[0118] Compared with device embodiment 1, the difference between comparative examples 1-3 is that FRD001 in the organic electroluminescent device is changed to RD-1, RD-2, and RD-3 which are well known in the industry and have been commercially applied. The obtained device performance test data are shown in Table 5.

[0119] Compared with device example 1, this comparative example 4 is different in that device example 1 does not contain the materials of the present invention or RD1-RD3, and the light-emitting layer is composed of RH and PRD to form a phosphorescent light-emitting device. The obtained device performance test data is shown in Table 5.

[0120] The OLEDs were characterized by standard methods. For this purpose, the electroluminescence spectrum, the current efficiency (CE, measured in cd / A), the power efficiency (measured in lm / W) and the external quantum efficiency (EQE, measured in %) were determined, which were calculated as a function of the luminous density from a current / voltage / luminous density characteristic (IUL characteristic) exhibiting Lambertian emission characteristics. The EQE is expressed at 10 mA / cm 2 External quantum efficiency under T95, which means the device is at 20mA / cm 2 The device brightness is reduced to 95% of the working time, and the Peak and FWHM values ​​indicate that the device is at 10mA / cm 2 The device performances of Examples 1 to 56 of the present invention and Comparative Examples 1 to 3 are summarized in Table 6;

[0121] Table 6 Device performance

[0122]

[0123]

[0124]

[0125] As can be seen from Table 6, relative to the prior art, the use of material embodiments 1-56 of the present invention can improve the device life while narrowing the spectrum and improving the device efficiency. Compared with the comparative example, the spectral half-peak width of the device embodiment is reduced by an average of 10-20nm. Relative to Comparative Example 1, the spectral half-peak width of device embodiment 42 where FRD214 is located is reduced by 11nm, the efficiency is improved by 30.4%, and the life is improved by 810%. Relative to Comparative Example 3, the spectral half-peak width of device embodiment 13 where FRD072 is located is reduced by 15nm, the efficiency is improved by 84%, and the life is improved by 101%. Relative to Comparative Example 4, the spectral half-peak width of device embodiment 53 where FRD241 is located is reduced by 22nm, the efficiency is improved by 26.4%, and the life is improved by 28.6%.

[0126] The dicarbazole pyrene structure in the present invention has strong rigidity and can effectively suppress non-radiative vibration, thereby improving device efficiency. Moreover, the steric hindering groups such as diarylamine or tert-butyl are connected to the periphery of the dicarbazole pyrene structure, which can effectively suppress aggregation and improve device life; at the same time, the electron-donating group makes it have a shallow HOMO / LUMO energy level. Increase the device life.

Claims

1. A biscarbazopyrene compound for an organic electroluminescent device, characterized in that: The compound is represented by formula (1) to formula (8): wherein a and b are each an integer from 1 to 7, and r is an integer from 1 to 6; When there are multiple R1 and R2, the multiple R1 and R2 may be the same or different; The R1 and R2 are selected from hydrogen, fluorine, substituted or unsubstituted alkyl having 1 to 50 carbon atoms, substituted or unsubstituted cycloalkyl having 3 to 50 ring carbon atoms, substituted or unsubstituted aryl having 6 to 50 ring carbon atoms, substituted or unsubstituted arylamine having 6 to 50 ring carbon atoms, substituted or unsubstituted monovalent heterocyclic group having 5 to 50 ring atoms, and substituted or unsubstituted silyl.

2. The biscarbazopyrene 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.

3. The biscarbazopyrene compound for an organic electroluminescent device according to claim 1 or 2, characterized in that: The R1 and R2 are selected from hydrogen, fluorine, substituted or unsubstituted alkyl having 1 to 20 carbon atoms, substituted or unsubstituted cycloalkyl having 3 to 8 ring carbon atoms, substituted or unsubstituted aryl having 6 to 10 ring carbon atoms, substituted or unsubstituted diphenylamino, substituted or unsubstituted monovalent heterocyclic group having 5 to 10 ring atoms, and substituted or unsubstituted silyl.

4. The biscarbazopyrene compound for an organic electroluminescent device according to claim 1 or 2, characterized in that: The R1 and R2 are selected from hydrogen, a substituted or unsubstituted alkyl group having 1 to 6 carbon atoms, and a substituted or unsubstituted diphenylamino group.

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

6. 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 5.

7. The organic electroluminescent device according to claim 6, characterized in that: The compound is used as a light-emitting material in an organic electroluminescent device.

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