Luminescent auxiliary material as well as preparation method and application thereof

Abstract

The invention discloses a light-emitting auxiliary material as well as a preparation method and application thereof, and relates to the technical field of light-emitting materials. According to the novel light-emitting auxiliary material provided by the invention, the hole mobility of the compound can be improved and the space structure can be changed by prolonging molecular conjugation of side chain groups on the compound, so that the compound is more adaptive to a device, the service life of the OLED device can be effectively prolonged, the light-emitting efficiency of the OLED device can be effectively improved, and meanwhile, the driving voltage is reduced.

Description

[0001] This application is a divisional application. The application date of the original application is May 20, 2022, the application number is 2022105584668, and the name is “A luminescent auxiliary material, its preparation method and application”. Technical Field

[0002] The present invention relates to the technical field of luminescent materials, and in particular to a luminescent auxiliary material, a preparation method thereof, and applications thereof. Background Art

[0003] OLED materials are divided into luminescent materials, hole transport materials, and electron transport materials. Hole transport materials typically have low highest occupied molecular orbital (HOMO) values, causing excitons generated in the luminescent layer to diffuse to the hole transport layer interface or to the side of the hole transport layer. This ultimately leads to luminescence at the interface within the luminescent layer or charge imbalance within the luminescent layer, resulting in light emission at the hole transport layer interface, reducing the color purity and efficiency of the organic electroluminescent device and shortening its lifespan. Introducing a luminescent auxiliary layer between the luminescent layer and the hole transport layer can effectively avoid these technical issues.

[0004] At present, the materials used as light-emitting auxiliary layers are limited. Most of these materials use fluorene ring structures. They have high hole mobility and high T1 energy to block the excitons after recombination from expanding to the transport layer, thereby improving the overall efficiency of the device. At the same time, the appropriate HOMO value reduces the transmission barrier of holes from the transport layer to the light-emitting layer, thereby reducing the device driving voltage and improving the lifespan.

[0005] So far, stable and efficient organic layer materials for organic electrical components have not been fully developed. How to develop a new luminescent auxiliary material to improve the lifespan and luminous efficiency of OLED devices while reducing the driving voltage has always been a problem that technicians in this field need to solve.

[0006] In view of this, the present invention is proposed. Summary of the Invention

[0007] The object of the present invention is to provide a luminescence auxiliary material and a preparation method thereof, aiming to utilize the luminescence auxiliary material to increase the lifespan and luminescence efficiency of OLED devices while reducing the driving voltage.

[0008] Another object of the present invention is to provide an organic electroluminescent device having the advantages of long service life, good luminous efficiency and low driving voltage.

[0009] The third object of the present invention is to improve the application of the above-mentioned organic electroluminescent device in the preparation of organic light-emitting devices or organic thin film transistors.

[0010] The present invention is achieved in that:

[0011] In a first aspect, the present invention provides a luminescence auxiliary material, the structural formula of which is shown in Formula I:

[0012]

[0013] wherein X represents oxygen or sulfur;

[0014] Ar is selected from any one of a substituted or unsubstituted C6-C30 aryl group and a substituted or unsubstituted 3-20-membered heteroaryl group, and the heteroatom in the heteroaryl group is selected from oxygen, nitrogen or sulfur, and Ar is cyclic with a benzene ring;

[0015] L is selected from a linker or wherein R3 is selected from any one of a substituted or unsubstituted C1-C30 alkyl group, a substituted or unsubstituted C1-C30 alkoxy group, a substituted or unsubstituted C3-C30 cycloalkyl group, a substituted or unsubstituted 3-30-membered heterocycloalkyl group, a substituted or unsubstituted C6-C30 aryl group, and a substituted or unsubstituted 3-30-membered heteroaryl group, and the heteroatoms in the heterocycloalkyl group and the heteroaryl group are independently selected from oxygen, nitrogen, or sulfur;

[0016] R1 and R2 are each independently selected from any one of hydrogen, substituted or unsubstituted C1-C30 alkyl, substituted or unsubstituted C3-C30 cycloalkyl, substituted or unsubstituted 3-30-membered heterocycloalkyl, substituted or unsubstituted C6-C30 aryl, and substituted or unsubstituted 3-30-membered heteroaryl, and the heteroatoms in the heterocycloalkyl and heteroaryl groups are independently selected from oxygen, nitrogen, or sulfur;

[0017] Ar1 and Ar2 are each independently selected from any one of a substituted or unsubstituted 3-30 membered heterocycloalkyl, a substituted or unsubstituted C6-C30 aryl and a substituted or unsubstituted 3-30 membered heteroaryl, and the heteroatoms in the heterocycloalkyl and heteroaryl groups are independently selected from oxygen, nitrogen or sulfur.

[0018] In a second aspect, the present invention also provides a method for preparing a luminescent auxiliary material, the synthesis route of which is as follows:

[0019]

[0020] wherein Hal1, Hal2 and Hal3 are each independently selected from halogen.

[0021] In a third aspect, the present invention further provides an organic electroluminescent device comprising a first electrode, a second electrode and an organic layer disposed between the first electrode and the second electrode, wherein the organic layer contains the luminescence auxiliary material of the above embodiment.

[0022] In a fourth aspect, the present invention further provides use of the organic electroluminescent device in preparing an organic light-emitting device or an organic thin film transistor.

[0023] The present invention has the following beneficial effects: The present invention provides a new type of luminescent auxiliary material, which can improve the hole mobility of the compound and change the spatial structure by extending the molecular conjugation of the side chain groups on the compound, thereby making it more adaptable to the device, and can effectively improve the lifespan and luminous efficiency of the OLED device while reducing the driving voltage. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the following briefly introduces the drawings required for use in the embodiments. It should be understood that the following drawings only illustrate certain embodiments of the present invention and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other relevant drawings can be obtained based on these drawings without paying any creative work.

[0025] Figure 1 The hydrogen nuclear magnetic resonance spectrum of the product prepared in Example 1 is shown. DETAILED DESCRIPTION

[0026] To make the purpose, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention are described clearly and completely below. Where specific conditions are not specified in the embodiments, conventional conditions or conditions recommended by the manufacturer are used. Where the manufacturer of the reagents or instruments is not specified, all are conventional products that can be purchased commercially.

[0027] The term "substituted or unsubstituted" herein means substituted with one, two, or more substituents selected from the group consisting of deuterium, a halogen group, a nitrile group, a hydroxyl group, a carbonyl group, an ester group, a silyl group, a boron group, a substituted or unsubstituted alkyl group, a substituted or unsubstituted cycloalkyl group, a substituted or unsubstituted alkoxy group, a substituted or unsubstituted alkenyl group, a substituted or unsubstituted alkylamino group, a substituted or unsubstituted heterocyclylamino group, a substituted or unsubstituted arylamino group, a substituted or unsubstituted aryl group, and a substituted or unsubstituted heterocyclyl group, or substituted with two or more of the substituents listed above that are linked together, or having no substituents. For example, "a substituent in which two or more substituents are linked together" may include a biphenyl group. In other words, a biphenyl group may be an aryl group, or may be interpreted as a substituent in which two phenyl groups are linked together.

[0028] An embodiment of the present invention provides a luminescence auxiliary material, the structural formula of which is shown in Formula I:

[0029]

[0030] Wherein, X in the general formula I represents oxygen (O) or sulfur (S), and can be either oxygen or sulfur.

[0031] In Formula I, Ar is selected from any one of a substituted or unsubstituted C6-C30 aryl group and a substituted or unsubstituted 3-20 membered heteroaryl group, and the heteroatom in the heteroaryl group is selected from oxygen (O), nitrogen (N), or sulfur (S), and Ar is fused to the benzene ring, and the fusion sites can be 1, 2, 2, 3, or 3, 4. Specifically, a C6-C30 aryl group refers to an aryl group having 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, or 30 carbon atoms. Similarly, a 3-20 membered heteroaryl group is named according to the number of carbon atoms, and its specific meaning is not specifically described here.

[0032] In the general formula I, L is selected from a connecting bond or When L is a connecting bond, the N atom is directly connected to the benzene ring.

[0033] Specifically, R3 is selected from any one of substituted or unsubstituted C1-C30 alkyl, substituted or unsubstituted C1-C30 alkoxy, substituted or unsubstituted C3-C30 cycloalkyl, substituted or unsubstituted 3-30 membered heterocycloalkyl, substituted or unsubstituted C6-C30 aryl and substituted or unsubstituted 3-30 membered heteroaryl, and the heteroatoms in the heterocycloalkyl and heteroaryl groups are independently selected from oxygen, nitrogen or sulfur.

[0034] In the general formula I, R1 and R2 are each independently selected from any one of hydrogen, substituted or unsubstituted C1-C30 alkyl, substituted or unsubstituted C3-C30 cycloalkyl, substituted or unsubstituted 3-30 membered heterocycloalkyl, substituted or unsubstituted C6-C30 aryl and substituted or unsubstituted 3-30 membered heteroaryl, and the heteroatoms in the heterocycloalkyl and heteroaryl groups are independently selected from oxygen, nitrogen or sulfur.

[0035] In the general formula I, Ar1 and Ar2 are each independently selected from any one of a substituted or unsubstituted 3-30 membered heterocycloalkyl, a substituted or unsubstituted C6-C30 aryl and a substituted or unsubstituted 3-30 membered heteroaryl, and the heteroatoms in the heterocycloalkyl and heteroaryl groups are independently selected from oxygen, nitrogen or sulfur.

[0036] It should be noted that by selecting groups such as R1, R2, Ar1 and Ar2 and extending the molecular conjugation, the hole mobility of the compound can be improved and the spatial structure can be changed, making it more adaptable to the device, which can effectively improve the life and luminous efficiency of the OLED device while reducing the driving voltage.

[0037] To further improve the lifespan and luminous efficiency of OLED devices while reducing the driving voltage, the inventors optimized the selection of various groups:

[0038] In a preferred embodiment, Ar is selected from any one of phenyl, biphenyl, terphenyl, naphthyl, anthracenyl and phenanthrenyl, and Ar is fused with the adjacent benzene ring on the parent nucleus to form a ring; the structural formula of the luminescent auxiliary material is any one of the general formulas II-1 to II-12:

[0039]

[0040] In a preferred embodiment, L is selected from any one of the following groups:

[0041] In a preferred embodiment, R1 and R2 are each independently selected from any one of the following groups:

[0042]

[0043] Specifically, the groups selected for R1 and R2 can be the same or different, and each is independently selected from the above groups.

[0044] In a preferred embodiment, Ar1 and Ar2 are each independently selected from one or a combination of the following groups:

[0045]

[0046] Specifically, the groups selected for Ar1 and Ar2 can be the same or different, and each is independently selected from the above groups. It can be one group or a combination of several groups, which is not limited here.

[0047] In a more preferred embodiment, the luminescent auxiliary material is selected from any one of compounds 1-263. The following 263 compounds, when applied to OLED devices, can significantly improve the lifespan and luminous efficiency of OLED devices while reducing the driving voltage. Compounds 1-263 are specifically:

[0048]

[0049]

[0050]

[0051]

[0052]

[0053]

[0054]

[0055]

[0056]

[0057]

[0058]

[0059]

[0060]

[0061]

[0062]

[0063] The present invention also provides a method for preparing the above-mentioned luminescence auxiliary material, and the synthesis route thereof is as follows:

[0064]

[0065] Specifically, the selection of R1, R2, X, L, Ar1 and Ar2 in the reaction scheme refers to the introduction of the luminescent auxiliary material (Formula I), which will not be repeated here. Hal1, Hal2 and Hal3 are each independently selected from halogen, such as fluorine, chlorine, bromine or iodine.

[0066] The specific steps of the above synthetic route are as follows:

[0067] (1) After raw materials A and B are dissolved in toluene, Pd2(dba)3, P(t-Bu)3 and t-BuONa are added under N2 atmosphere, the temperature is raised to 105-115°C and stirred for reaction for 8-12 hours. After the reaction is completed, diatomaceous earth is used for hot filtration to remove salt and catalyst. After the filtrate is cooled to room temperature, distilled water is added to the filtrate for washing. After separation, the organic phase is retained, the aqueous phase is extracted with ethyl acetate, and the combined organic layer is dried with magnesium sulfate. The solvent is removed using a rotary evaporator. Finally, a mixture of dichloromethane and petroleum ether is used as an eluent, and the remaining substance is purified by column chromatography to obtain the compound shown in Intermediate 1.

[0068] (2) After the intermediate 1 and the raw material C are dissolved in toluene, Pd2(dba)3, P(t-Bu)3 and t-BuONa are added under a N2 atmosphere, the temperature is raised to 105-115°C and the reaction is stirred for 8-12 hours. After the reaction is completed, the salt and catalyst are removed by hot filtration using diatomaceous earth. After the filtrate is cooled to room temperature, distilled water is added to the filtrate for washing. After separation, the organic phase is retained, the aqueous phase is extracted with ethyl acetate, and the combined organic layer is dried with magnesium sulfate, and the solvent is removed using a rotary evaporator. Finally, the remaining substance is purified by column chromatography using a mixture of dichloromethane and petroleum ether as an eluent to obtain the compound represented by intermediate 2.

[0069] (3) Under N2 protection, intermediate 2, raw material D, tetrakis(triphenylphosphine)palladium and potassium carbonate are added to a mixed solvent of toluene, ethanol and water, respectively, and the temperature is raised to 90-100°C for reaction for 8-10 hours. After the reaction is completed, the mixture is cooled to room temperature. After the solid is precipitated, it is filtered and washed with water to remove salt. The solid is then rinsed with a small amount of ethanol, and the filter cake is dried and placed in a methanol solution for recrystallization to obtain the compound represented by the above general formula 1.

[0070] The present invention also provides an organic electroluminescent device comprising a first electrode, a second electrode, and an organic layer disposed between the first and second electrodes, wherein the organic layer contains the aforementioned light-assisting material. The structure of the organic layer is not limited and can be at least one layer.

[0071] In some embodiments, the organic layer includes a hole injection layer, a hole transport layer, a luminescence-assisting layer, a light-emitting layer, a hole blocking layer, an electron transport layer, and an electron injection layer, arranged in sequence. The luminescence-assisting layer is prepared using a luminescence-assisting material. The inventors have discovered that using the luminescence-assisting material provided in embodiments of the present invention as the luminescence-assisting layer can significantly improve the lifespan and luminous efficiency of OLED devices while reducing the driving voltage.

[0072] Furthermore, the organic electroluminescent device can be further prepared into products such as organic light-emitting devices or organic thin film transistors, and has broad application prospects.

[0073] The features and performance of the present invention are further described in detail below with reference to the embodiments.

[0074] It should be noted that the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. All other embodiments obtained by ordinary technicians in this field based on the embodiments of the present invention without making any creative efforts shall fall within the scope of protection of the present invention.

[0075] Example 1

[0076] This embodiment provides a method for preparing a luminescent auxiliary material, comprising the following steps:

[0077]

[0078] After raw material A (40.00 mmol) and raw material B (40.00 mmol) were dissolved in toluene, Pd2(dba)3 (0.40 mmol), P(t-Bu)3 (2.00 mmol) and t-BuONa (80.00 mmol) were added under N2 atmosphere, the temperature was raised to 115°C and the reaction was stirred for 12 hours. After the reaction was completed, diatomaceous earth was used for hot filtration to remove salt and catalyst. After the filtrate was cooled to room temperature, distilled water was added to the filtrate for washing. After separation, the organic phase was retained, the aqueous phase was extracted with ethyl acetate, and the combined organic layers were dried over magnesium sulfate. The solvent was removed using a rotary evaporator. Finally, a mixture of dichloromethane and petroleum ether (V:V=1:16) was used as an eluent, and the remaining substance was purified by column chromatography to obtain the compound shown in Intermediate 1 (10.18 g, yield: 79.26%).

[0079] Intermediate 1 (31.67 mmol) and raw material C (31.67 mmol) were dissolved in toluene, and Pd2(dba)3 (0.31 mmol), P(t-Bu)3 (1.58 mmol) and t-BuONa (63.34 mmol) were added under N2 atmosphere. The temperature was raised to 115°C and stirred for 8 hours. After the reaction, diatomaceous earth was used for hot filtration to remove salt and catalyst. After the filtrate was cooled to room temperature, distilled water was added to the filtrate for washing. After separation, the organic phase was retained and the aqueous phase was extracted with ethyl acetate. The combined organic layers were dried over magnesium sulfate and the solvent was removed using a rotary evaporator. Finally, a mixture of dichloromethane and petroleum ether (V:V=1:8) was used as an eluent and the remaining substance was purified by column chromatography to obtain the compound shown in Intermediate 2 (12.12 g, yield: 75.34%).

[0080] Under N2 protection, intermediate 2 (23.85 mmol), raw material D (26.23 mmol), tetrakistriphenylphosphine palladium (0.23 mmol) and potassium carbonate (47.70 mmol) were respectively added to a mixed solvent of toluene, ethanol and water, and the temperature was raised to 100°C for reaction for 10 h. After the reaction was completed, the mixture was cooled to room temperature. After the solid was precipitated, it was filtered and washed with water to remove salt. It was then rinsed with a small amount of ethanol, the filter cake was dried, and placed in methanol solution for recrystallization to obtain compound 1; (13.22 g, yield: 80.37%, Mw: 689.86).

[0081] The obtained compound-1 was tested and analyzed, and the results were as follows:

[0082] HPLC purity: >99.95%.

[0083] Mass spectrometry test: theoretical value is 689.86; tested value is 689.69.

[0084] Elemental analysis:

[0085] Calculated values: C, 90.54; H, 5.11; N, 2.03; O, 2.32.

[0086] The test values ​​are: C, 90.16; H, 5.45; N, 2.23; O, 2.41.

[0087] The NMR images of the products prepared in the embodiment are as follows Figure 1 shown.

[0088] Example 2

[0089] This embodiment provides a method for preparing a luminescent auxiliary material, comprising the following steps:

[0090]

[0091] After raw material A (40.00 mmol) and raw material B (40.00 mmol) were dissolved in toluene, Pd2(dba)3 (0.40 mmol), P(t-Bu)3 (2.00 mmol) and t-BuONa (80.00 mmol) were added under N2 atmosphere, the temperature was raised to 115°C and the reaction was stirred for 12 hours. After the reaction was completed, diatomaceous earth was used for hot filtration to remove salt and catalyst. After the filtrate was cooled to room temperature, distilled water was added to the filtrate for washing. After separation, the organic phase was retained, the aqueous phase was extracted with ethyl acetate, and the combined organic layers were dried over magnesium sulfate. The solvent was removed using a rotary evaporator. Finally, a mixture of dichloromethane and petroleum ether (V:V=1:16) was used as an eluent, and the remaining substance was purified by column chromatography to obtain the compound shown in Intermediate 1 (10.11 g, yield: 78.69%).

[0092] Intermediate 1 (31.45 mmol) and raw material C (31.45 mmol) were dissolved in toluene, and Pd2(dba)3 (0.31 mmol), P(t-Bu)3 (1.57 mmol) and t-BuONa (62.90 mmol) were added under N2 atmosphere. The temperature was raised to 115°C and stirred for 8 h. After the reaction, diatomaceous earth was used for hot filtration to remove salt and catalyst. After the filtrate was cooled to room temperature, distilled water was added to the filtrate for washing. After separation, the organic phase was retained and the aqueous phase was extracted with ethyl acetate. The combined organic layers were dried over magnesium sulfate and the solvent was removed using a rotary evaporator. Finally, a mixture of dichloromethane and petroleum ether (V:V=1:8) was used as an eluent and the remaining substance was purified by column chromatography to obtain the compound shown in Intermediate 2 (10.45 g, yield: 76.97%).

[0093] Under N2 protection, intermediate 2 (24.19 mmol), raw material D (26.60 mmol), tetrakis(triphenylphosphine)palladium (0.24 mmol) and potassium carbonate (48.38 mmol) were respectively added to a mixed solvent of toluene, ethanol and water, and the temperature was raised to 100°C for reaction for 10 h. After the reaction was completed, the mixture was cooled to room temperature. After the solid was precipitated, it was filtered and washed with water to remove salt. It was then rinsed with a small amount of ethanol, the filter cake was dried, and placed in methanol solution for recrystallization to obtain compound 7; (11.82 g, yield: 79.65%, Mw: 613.76).

[0094] The obtained compound 7 was tested and analyzed, and the results were as follows:

[0095] HPLC purity: >99.95%.

[0096] Mass spectrometry test: theoretical value is 613.76; tested value is 613.97.

[0097] Elemental analysis:

[0098] Calculated values: C, 90.02; H, 5.09; N, 2.28; O, 2.61.

[0099] The test values ​​are: C, 89.88; H, 5.21; N, 2.35; O, 2.73.

[0100] Example 3

[0101] This embodiment provides a method for preparing a luminescent auxiliary material, comprising the following steps:

[0102]

[0103] After raw material A (40.00 mmol) and raw material B (40.00 mmol) were dissolved in toluene, Pd2(dba)3 (0.40 mmol), P(t-Bu)3 (2.00 mmol) and t-BuONa (80.00 mmol) were added under N2 atmosphere, the temperature was raised to 115°C and the reaction was stirred for 12 hours. After the reaction was completed, diatomaceous earth was used for hot filtration to remove salt and catalyst. After the filtrate was cooled to room temperature, distilled water was added to the filtrate for washing. After separation, the organic phase was retained, the aqueous phase was extracted with ethyl acetate, and the combined organic layers were dried over magnesium sulfate. The solvent was removed using a rotary evaporator. Finally, a mixture of dichloromethane and petroleum ether (V:V=1:16) was used as an eluent, and the remaining substance was purified by column chromatography to obtain the compound shown in Intermediate 1 (12.35 g, yield: 77.69%).

[0104] Intermediate 1 (31.06 mmol) and raw material C (31.06 mmol) were dissolved in toluene, and Pd2(dba)3 (0.31 mmol), P(t-Bu)3 (1.55 mmol) and t-BuONa (62.12 mmol) were added under N2 atmosphere. The temperature was raised to 115°C and stirred for 8 h. After the reaction, diatomaceous earth was used for hot filtration to remove salt and catalyst. After the filtrate was cooled to room temperature, distilled water was added to the filtrate for washing. After separation, the organic phase was retained and the aqueous phase was extracted with ethyl acetate. The combined organic layers were dried over magnesium sulfate and the solvent was removed using a rotary evaporator. Finally, a mixture of dichloromethane and petroleum ether (V:V=1:8) was used as an eluent and the remaining substance was purified by column chromatography to obtain the compound shown in Intermediate 2 (11.78 g, yield: 74.69%).

[0105] Under N2 protection, intermediate 2 (23.18 mmol), raw material D (25.49 mmol), tetrakistriphenylphosphine palladium (0.23 mmol) and potassium carbonate (46.36 mmol) were respectively added to a mixed solvent of toluene, ethanol and water, and the temperature was raised to 100°C for 10 h. After the reaction was completed, the mixture was cooled to room temperature. After the solid was precipitated, it was filtered and washed with water to remove salt. It was then rinsed with a small amount of ethanol, the filter cake was dried, and placed in methanol solution for recrystallization to obtain compound 80; (12.49 g, yield: 78.13%, Mw: 689.86).

[0106] The obtained compound-80 was tested and analyzed, and the results were as follows:

[0107] HPLC purity: >99.95%.

[0108] Mass spectrometry test: theoretical value is 689.86; tested value is 689.62.

[0109] Elemental analysis:

[0110] Calculated values: C, 90.54; H, 5.11; N, 2.03; O, 2.32.

[0111] The test values ​​are: C,90.23H,5.41; N,2.31; O,2.39.

[0112] Example 4

[0113] This embodiment provides a method for preparing a luminescent auxiliary material, comprising the following steps:

[0114]

[0115] After raw material A (40.00 mmol) and raw material B (40.00 mmol) were dissolved in toluene, Pd2(dba)3 (0.40 mmol), P(t-Bu)3 (2.00 mmol) and t-BuONa (80.00 mmol) were added under N2 atmosphere, the temperature was raised to 115°C and the reaction was stirred for 12 hours. After the reaction was completed, diatomaceous earth was used for hot filtration to remove salt and catalyst. After the filtrate was cooled to room temperature, distilled water was added to the filtrate for washing. After separation, the organic phase was retained, the aqueous phase was extracted with ethyl acetate, and the combined organic layers were dried over magnesium sulfate. The solvent was removed using a rotary evaporator. Finally, a mixture of dichloromethane and petroleum ether (V:V=1:16) was used as an eluent, and the remaining substance was purified by column chromatography to obtain the compound shown in Intermediate 1 (10.31 g, yield: 80.25%).

[0116] Intermediate 1 (32.07 mmol) and raw material C (32.07 mmol) were dissolved in toluene, and Pd2(dba)3 (0.32 mmol), P(t-Bu)3 (1.60 mmol) and t-BuONa (64.14 mmol) were added under N2 atmosphere. The temperature was raised to 115°C and stirred for 8 hours. After the reaction, the salt and catalyst were removed by hot filtration using diatomaceous earth. After the filtrate was cooled to room temperature, distilled water was added to the filtrate for washing. After separation, the organic phase was retained and the aqueous phase was extracted with ethyl acetate. The combined organic layers were dried over magnesium sulfate and the solvent was removed using a rotary evaporator. Finally, the remaining substance was purified by column chromatography using a mixture of dichloromethane and petroleum ether (V:V=1:8) as eluent to obtain the compound shown in Intermediate 2 (12.41 g, yield: 76.19%).

[0117] Under N2 protection, intermediate 2 (24.42 mmol), raw material D (26.86 mmol), tetrakistriphenylphosphine palladium (0.24 mmol) and potassium carbonate (48.84 mmol) were respectively added to a mixed solvent of toluene, ethanol and water, and the temperature was raised to 100°C for reaction for 10 h. After the reaction was completed, the mixture was cooled to room temperature. After the solid was precipitated, it was filtered and washed with water to remove salt. It was then rinsed with a small amount of ethanol, the filter cake was dried, and placed in methanol solution for recrystallization to obtain compound 143; (13.66 g, yield: 81.16%, Mw: 689.86).

[0118] The obtained compound-143 was tested and analyzed, and the results were as follows:

[0119] HPLC purity: >99.95%.

[0120] Mass spectrometry test: theoretical value is 689.86; tested value is 689.69.

[0121] Elemental analysis:

[0122] Calculated values: C, 90.54; H, 5.11; N, 2.03; O, 2.32.

[0123] The test values ​​are: C, 90.23; H, 5.32; N, 2.19; O, 2.41.

[0124] Example 5

[0125] This embodiment provides a method for preparing a luminescent auxiliary material, comprising the following steps:

[0126]

[0127] After raw material A (40.00 mmol) and raw material B (40.00 mmol) were dissolved in toluene, Pd2(dba)3 (0.40 mmol), P(t-Bu)3 (2.00 mmol) and t-BuONa (80.00 mmol) were added under N2 atmosphere, the temperature was raised to 115°C and the reaction was stirred for 12 hours. After the reaction was completed, diatomaceous earth was used for hot filtration to remove salt and catalyst. After the filtrate was cooled to room temperature, distilled water was added to the filtrate for washing. After separation, the organic phase was retained, the aqueous phase was extracted with ethyl acetate, and the combined organic layers were dried over magnesium sulfate. The solvent was removed using a rotary evaporator. Finally, a mixture of dichloromethane and petroleum ether (V:V=1:16) was used as an eluent, and the remaining substance was purified by column chromatography to obtain the compound shown in Intermediate 1 (10.18 g, yield: 79.25%).

[0128] Intermediate 1 (31.67 mmol) and raw material C (31.67 mmol) were dissolved in toluene, and Pd2(dba)3 (0.31 mmol), P(t-Bu)3 (1.58 mmol) and t-BuONa (63.34 mmol) were added under N2 atmosphere. The temperature was raised to 115°C and stirred for 8 hours. After the reaction, diatomaceous earth was used for hot filtration to remove salt and catalyst. After the filtrate was cooled to room temperature, distilled water was added to the filtrate for washing. After separation, the organic phase was retained and the aqueous phase was extracted with ethyl acetate. The combined organic layers were dried over magnesium sulfate and the solvent was removed using a rotary evaporator. Finally, a mixture of dichloromethane and petroleum ether (V:V=1:8) was used as an eluent and the remaining substance was purified by column chromatography to obtain the compound shown in Intermediate 2 (12.25 g, yield: 76.19%).

[0129] Under N2 protection, intermediate 2 (24.11 mmol), raw material D (26.52 mmol), tetrakis(triphenylphosphine)palladium (0.24 mmol) and potassium carbonate (48.22 mmol) were respectively added to a mixed solvent of toluene, ethanol and water, and the temperature was raised to 100°C for reaction for 10 h. After the reaction was completed, the mixture was cooled to room temperature. After the solid was precipitated, it was filtered and washed with water to remove salt. It was then rinsed with a small amount of ethanol, the filter cake was dried, and placed in methanol solution for recrystallization to obtain compound 211; (14.69 g, yield: 79.61%, Mw: 765.96).

[0130] The obtained compound-211 was tested and analyzed, and the results were as follows:

[0131] HPLC purity: >99.95%.

[0132] Mass spectrometry test: theoretical value is 765.96; tested value is 766.23.

[0133] Elemental analysis:

[0134] Calculated values: C, 90.95; H, 5.13; N, 1.83; O, 2.09.

[0135] The test values ​​are: C, 90.31; H, 5.41; N, 2.15; O, 2.31.

[0136] Example 6

[0137] This embodiment provides a method for preparing a luminescent auxiliary material, comprising the following steps:

[0138]

[0139] After raw material A (40.00 mmol) and raw material B (40.00 mmol) were dissolved in toluene, Pd2(dba)3 (0.40 mmol), P(t-Bu)3 (2.00 mmol) and t-BuONa (80.00 mmol) were added under N2 atmosphere, the temperature was raised to 115°C and the reaction was stirred for 12 hours. After the reaction was completed, diatomaceous earth was used for hot filtration to remove salt and catalyst. After the filtrate was cooled to room temperature, distilled water was added to the filtrate for washing. After separation, the organic phase was retained, the aqueous phase was extracted with ethyl acetate, and the combined organic layers were dried over magnesium sulfate. The solvent was removed using a rotary evaporator. Finally, a mixture of dichloromethane and petroleum ether (V:V=1:16) was used as an eluent, and the remaining substance was purified by column chromatography to obtain the compound shown in Intermediate 1 (10.10 g, yield: 78.67%).

[0140] Intermediate 1 (31.42 mmol) and raw material C (31.42 mmol) were dissolved in toluene, and Pd2(dba)3 (0.31 mmol), P(t-Bu)3 (1.57 mmol) and t-BuONa (62.84 mmol) were added under N2 atmosphere. The temperature was raised to 115°C and stirred for 8 h. After the reaction, diatomaceous earth was used for hot filtration to remove salt and catalyst. After the filtrate was cooled to room temperature, distilled water was added to the filtrate for washing. After separation, the organic phase was retained and the aqueous phase was extracted with ethyl acetate. The combined organic layers were dried over magnesium sulfate and the solvent was removed using a rotary evaporator. Finally, a mixture of dichloromethane and petroleum ether (V:V=1:8) was used as an eluent and the remaining substance was purified by column chromatography to obtain the compound shown in Intermediate 2 (12.10 g, yield: 75.87%).

[0141] Under N2 protection, intermediate 2 (23.81 mmol), raw material D (26.19 mmol), tetrakis(triphenylphosphine)palladium (0.23 mmol) and potassium carbonate (47.62 mmol) were respectively added to a mixed solvent of toluene, ethanol and water, and the temperature was raised to 100°C for 10 h. After the reaction was completed, the mixture was cooled to room temperature. After the solid was precipitated, it was filtered and washed with water to remove salt. It was then rinsed with a small amount of ethanol, the filter cake was dried, and placed in methanol solution for recrystallization to obtain compound 234; (14.67 g, yield: 80.51%, Mw: 765.96).

[0142] The obtained compound-234 was tested and analyzed, and the results were as follows:

[0143] HPLC purity: >99.95%.

[0144] Mass spectrometry test: theoretical value is 765.96; tested value is 765.74.

[0145] Elemental analysis:

[0146] Calculated values: C, 90.95; H, 5.13; N, 1.83; O, 2.09.

[0147] The test values ​​are: C, 90.26; H, 5.37; N, 2.12; O, 2.26.

[0148] The structural formula of the compounds prepared in the above examples is the general formula 1 in the content of the invention. The synthesis routes and principles of other compounds are the same as those in the above examples, so they are not listed here in detail.

[0149] According to the above preparation method, the luminescence auxiliary material shown in Table 1 below can be obtained:

[0150] Table 1 Summary of luminescence auxiliary materials prepared in other examples

[0151] Compound Molecular formula Mass spectrometry calculated values Mass spectrometry test value Yield (%) Compound 9 C46H31NO 613.76 613.49 79.13 Compound 13 C46H29NO2 627.74 627.48 74.58 Compound 14 C42H27NO 561.68 561.48 76.35 Compound 18 C50H33NO 663.82 663.64 78.65 Compound 23 C54H35NO 713.88 713.69 74.21 Compound 28 C52H35NO 689.86 691.02 75.58 Compound 33 C54H35NO 713.88 714.13 76.05 Compound 40 C58H39NO 765.96 766.12 77.24 Compound 49 C58H39NO 765.96 765.74 79.33 Compound 55 C52H35NO 689.86 689.61 77.34 Compound 65 C42H27NO 561.68 561.91 80.26 Compound 68 C55H39NO2 745.92 745.68 76.59 Compound 70 C52H35NO 689.86 689.58 75.89 Compound 76 C58H39NO 765.96 765.64 70.11 Compound 84 C54H35NO 713.88 714.16 70.12 Compound 87 C56H37NO 739.92 740.24 69.35 Compound 91 C58H39NO 765.96 765.71 65.98 Compound 95 C60H39NO 789.98 789.67 70.35 Compound 106 C60H39NO 789.98 790.14 75.68 Compound 110 C52H33NO2 703.84 703.58 76.18 Compound 119 C42H27NO 561.68 561.87 81.64 Compound 126 C46H31NO 613.76 613.49 79.19 Compound 130 C58H39NO 765.96 765.68 78.47 Compound 136 C56H37NO 739.92 739.68 75.24 Compound 141 C56H37NO 739.92 740.24 66.54 Compound 146 C62H41NO 816.02 816.34 68.59 Compound 153 C52H35NO 689.86 689.73 71.33 Compound 156 C62H41NO 816.02 816.35 67.52 Compound 162 C62H41NO 816.02 715.89 78.24 Compound 165 C54H35NO 713.88 713.66 77.54 Compound 170 C62H41NO 816.02 816.3 69.14 Compound 173 C62H41NO 816.02 816.29 70.27 Compound 182 C53H34N2O 702.86 702.64 74.35 Compound 191 C62H40N2O 829.02 829.31 69.22 Compound 198 C64H41NO2 856.04 856.36 73.59 Compound 205 C52H33NOS 719.9 719.67 77.44 Compound 214 C52H35NO 689.86 689.57 68.52 Compound 218 C52H35NS 705.92 705.77 71.55 Compound 231 C55H39NO 729.92 730.18 69.67

[0152] An organic electroluminescent device is prepared using the luminescence auxiliary material prepared in the embodiment of the present invention. When the organic layer of the organic electroluminescent device includes a luminescence auxiliary layer, the luminescence auxiliary layer includes the luminescence auxiliary material provided in the above embodiment.

[0153] Device Example 1

[0154] The preparation of an organic electroluminescent device containing a luminescent auxiliary material specifically comprises the following steps:

[0155] a. ITO anode: Wash an ITO (indium tin oxide)-Ag-ITO (indium tin oxide) glass substrate with a coating thickness of 150nm in distilled water twice, ultrasonically clean it for 30 minutes, then repeatedly clean it with distilled water twice, ultrasonically clean it for 10 minutes, and then transfer it to a spin dryer for drying. Finally, bake it in a vacuum oven at 220℃ for 2 hours. After baking, cool it down and it can be used. Using this substrate as the anode, use an evaporation machine to carry out the evaporation device process, and then evaporate other functional layers on it in sequence.

[0156] b. HIL (hole injection layer): The evaporation rate of the hole injection layer is HT and P-dopant, and the chemical formula thereof is shown below. Among them, the evaporation rate ratio of HT and P-dopant is 97:3, and the thickness is 10 nm.

[0157] c. HTL (hole transport layer): At a deposition rate of , 120 nm of HT was vacuum evaporated on the hole injection layer as a hole transport layer.

[0158] d. Luminous auxiliary layer: At a deposition rate of , 10 nm of the compound 1 provided in Example 1 was vacuum-deposited on the hole transport layer as a light-emitting auxiliary layer.

[0159] e. EML (light-emitting layer): Then on the above-mentioned light-emitting auxiliary layer, At a deposition rate of , a host material (Host) and a dopant material (Dopant) with a thickness of 25 nm were vacuum-deposited as the light-emitting layer. The chemical formulas of the Host and Dopant are shown below; wherein, the deposition rate ratio of the Host and Dopant is 98:2.

[0160] f. HBL (hole blocking layer): At a deposition rate of , HB with a thickness of 5.0 nm was vacuum-deposited as a hole blocking layer, and its chemical formula is shown below.

[0161] g. ETL (Electron Transport Layer): At a deposition rate of , ET and Liq with a thickness of 30 nm were vacuum-deposited as the electron transport layer. The chemical formula of ET is shown below; wherein, the evaporation rate ratio of ET and Liq is 50:50.

[0162] h. EIL (electron injection layer): The evaporation rate is 1.0 nm, and a Yb film layer is evaporated to form an electron injection layer.

[0163] i. Cathode: The evaporation rate ratio of magnesium and silver is 18nm, and the evaporation rate ratio is 1:9 to obtain an OLED device. j. Light extraction layer: At a deposition rate of , CPL with a thickness of 70 nm was vacuum-deposited on the cathode as a light extraction layer.

[0164] k. Package the vapor-deposited substrate: First, use the glue coating equipment to coat the cleaned cover with UV glue, then move the coated cover to the pressing section, place the vapor-deposited substrate on the upper end of the cover, and finally bond the substrate and cover with the bonding equipment, and complete the light curing of the UV glue at the same time.

[0165] The structural formula involved in the preparation process is as follows:

[0166]

[0167] Referring to the method provided in the above device embodiment 1, compounds 7, 80, 143, 9, 13, 14, 18, 23, 28, 33, 40, 49, 55, 65, 68, 70, 76, 84, 87, 91, 95, 106, 110, 119, 126, 130, 136, 141, 146, 153, 156, 162, 165, 170, 173, 182, 191, 198, 205, 211, 214, 218, 231, 234 were respectively selected to replace compound 1 for evaporation of the light-emitting auxiliary layer, and the corresponding organic electroluminescent devices were prepared, which were respectively recorded as device embodiments 2-45.

[0168] Device Comparison Examples 1-6:

[0169] This comparative example provides an organic electroluminescent device. The only difference in the preparation method of this organic electroluminescent device from that of Device Example 1 is that the organic electroluminescent device is prepared by evaporating existing comparative compounds a, b, c, d, e, and f, respectively, instead of the luminescent auxiliary material (Compound 1) in Device Example 1. Comparative Examples 1-6 are prepared. The chemical structures of comparative compounds a, b, c, d, e, and f are:

[0170]

[0171] The driving voltage, luminous efficiency, BI value, and lifetime of the organic electroluminescent devices containing luminescent auxiliary materials obtained in the above-mentioned device application examples 1-45 and device comparative examples 1-6 were characterized at a brightness of 1000 (nits). The test results are shown in Table 2. Note: In blue top-emitting devices, current efficiency is significantly affected by chromaticity. Therefore, to take the influence of chromaticity on efficiency into account, the ratio of luminous efficiency to CIEy is defined as BI value, i.e., BI = (cd / A) / CIEy.

[0172] Table 2 Luminous characteristics test results (brightness value is 1000 nits)

[0173]

[0174]

[0175]

[0176] Note: In blue top-emitting devices, the current efficiency is greatly affected by chromaticity. Therefore, the influence of chromaticity on efficiency is taken into account, and the ratio of luminous efficiency to CIEy is defined as BI value, that is, BI = (cd / A) / CIEy.

[0177] As shown in Table 2, the organic electroluminescent devices prepared using the luminescent auxiliary materials provided by the present invention in Application Examples 1-45 are improved in driving voltage, luminous efficiency, BI and life compared with the existing organic electroluminescent devices provided by Comparative Examples 1-6.

[0178] This shows that compared with the comparative compounds, even with the same parent core, by changing the side chain and extending the molecular conjugation, the hole mobility of the compound can be improved and the spatial structure can be changed, making it more adaptable to the device, which can effectively improve the lifespan and luminous efficiency of the OLED device while reducing the driving voltage.

[0179] The various embodiments in this specification are described in a progressive manner, with each embodiment focusing on the differences from other embodiments. Reference can be made to the common and similar parts between the various embodiments. For the devices disclosed in the embodiments, since they correspond to the methods disclosed in the embodiments, the description is relatively simple, and the relevant parts can be referred to the method description.

[0180] The above are merely preferred embodiments of the present invention and are not intended to limit the present invention. Those skilled in the art will readily appreciate that various modifications and variations of the present invention are possible. Any modifications, equivalent substitutions, or improvements made within the spirit and principles of the present invention shall be included within the scope of protection of the present invention.

Claims

1. A luminescence auxiliary material, characterized in that: Its structural formula is shown in general formula I: wherein X represents oxygen or sulfur; Ar is selected from any one of a substituted or unsubstituted C6-C30 aryl group and a substituted or unsubstituted 3-20-membered heteroaryl group, and the heteroatom in the heteroaryl group is selected from oxygen, nitrogen or sulfur, and Ar is cyclic with a benzene ring; L is selected from a linker or wherein R3 is selected from any one of a substituted or unsubstituted C1-C30 alkyl group, a substituted or unsubstituted C1-C30 alkoxy group, a substituted or unsubstituted C3-C30 cycloalkyl group, a substituted or unsubstituted 3-30-membered heterocycloalkyl group, a substituted or unsubstituted C6-C30 aryl group, and a substituted or unsubstituted 3-30-membered heteroaryl group, and the heteroatoms in the heterocycloalkyl group and the heteroaryl group are independently selected from oxygen, nitrogen, or sulfur; R1 and R2 are each independently selected from any one of hydrogen, substituted or unsubstituted C1-C30 alkyl, substituted or unsubstituted C3-C30 cycloalkyl, substituted or unsubstituted 3-30-membered heterocycloalkyl, substituted or unsubstituted C6-C30 aryl, and substituted or unsubstituted 3-30-membered heteroaryl, and the heteroatoms in the heterocycloalkyl and heteroaryl groups are independently selected from oxygen, nitrogen, or sulfur; Ar1 and Ar2 are each independently selected from any one of a substituted or unsubstituted 3-30 membered heterocycloalkyl, a substituted or unsubstituted C6-C30 aryl and a substituted or unsubstituted 3-30 membered heteroaryl, and the heteroatoms in the heterocycloalkyl and heteroaryl are independently selected from oxygen, nitrogen or sulfur.

2. The luminescence auxiliary material according to claim 1, characterized in that Ar is selected from any one of phenyl, biphenyl, terphenyl, naphthyl, anthracenyl and phenanthryl, and Ar is fused with the adjacent benzene ring on the parent nucleus to form a ring; Preferably, the structural formula of the luminescence auxiliary material is any one of the general formulas II-1 to II-12:

3. The luminescence auxiliary material according to claim 1 or 2, characterized in that: L is selected from any one of the following groups:

4. The luminescence auxiliary material according to claim 3, characterized in that R1 and R2 are each independently selected from any one of the following groups:

5. The luminescence auxiliary material according to claim 4, characterized in that Ar1 and Ar2 are each independently selected from one or a combination of the following groups:

6. The luminescence auxiliary material according to claim 5, characterized in that The luminescence auxiliary material is selected from any one of compounds 1-263:

7. A method for preparing the luminescence auxiliary material according to any one of claims 1 to 6, characterized in that: Its synthetic route is as follows: wherein Hal1, Hal2 and Hal3 are each independently selected from halogen.

8. An organic electroluminescent device, characterized in that: The method comprises a first electrode, a second electrode and an organic layer arranged between the first electrode and the second electrode, wherein the organic layer contains the luminescence auxiliary material according to any one of claims 1 to 6.

9. The organic electroluminescent device according to claim 8, characterized in that: The organic layer includes a hole injection layer, a hole transport layer, a luminescence auxiliary layer, a luminescent layer, a hole blocking layer, an electron transport layer and an electron injection layer arranged in sequence, and the luminescence auxiliary layer is prepared using the luminescence auxiliary material.

10. Use of the organic electroluminescent device according to claim 9 in the preparation of an organic light-emitting device or an organic thin film transistor.

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