Organic luminescent compound suitable for solution processing, preparation method and organic electroluminescent device

Abstract

The invention relates to the technical field of organic electroluminescence, discloses an organic light-emitting compound suitable for solution processing, a preparation method of the organic light-emitting compound and an organic electroluminescence device, and provides the organic light-emitting compound suitable for solution processing. The structural formula of the organic light-emitting compound is as shown in formula (I): # imgabs0 #, the highest external quantum efficiency of electroluminescence of an organic light-emitting device prepared from the organic light-emitting compound reaches 30% or above, and the service life (T50, hour) of the organic light-emitting device reaches 800 hours or above.

Description

Technical Field

[0001] The present application relates to the technical field of organic electroluminescence, and mainly relates to an organic light-emitting compound suitable for solution processing, a preparation method thereof, and an organic electroluminescent device. Background Art

[0002] During the process of preparing an organic electroluminescent device using a solution processing method, the properties of the organic thin film are affected by factors such as processing conditions and the composition of the thin film. The multi-resonant TADF (Through-Space Charge Transfer) material has strong planarity, but during the process of preparing an organic electroluminescent device using a solution processing method, self-aggregation is serious, resulting in poor device performance of the prepared organic electroluminescent device. At present, there are also relevant reports that the device performance can be improved by introducing bulky groups to inhibit intermolecular packing. However, the improvement effect is not prominent.

[0003] Therefore, the existing technology still needs to be improved and developed. Summary of the Invention

[0004] In view of the above deficiencies of the prior art, the purpose of the present application is to provide an organic light-emitting compound suitable for solution processing, a preparation method thereof, and an organic electroluminescent device, aiming to solve the problem of poor device performance of the organic electroluminescent device prepared from the existing TADF material based on the solution processing method.

[0005] The technical solution of the present application is as follows:

[0006] An organic light-emitting compound suitable for solution processing, wherein its structural formula is shown in formula (I):

[0007]

[0008] Wherein, R1 and R2 are independently selected from C6-C30 aryl, C6-C18 aryl substituted by one or more R a substituted C6-C18 aryl, 5- to 18-membered heteroaryl, 5- to 18-membered heteroaryl substituted by one or more R a substituted carbazolyl, carbazolyl substituted by one or more R a substituted diphenylamino, diphenylamino substituted by one or more R a substituted diphenylamino;

[0009] R3, R4, and R5 are independently selected from hydrogen, deuterium, C3-C20 cycloalkyl, C6-C30 aryl, C6-C18 aryl substituted by one or more R a substituted C6-C18 aryl, 5- to 18-membered heteroaryl;

[0010] R aEach occurrence is independently deuterium, fluorine, C1-C12 alkyl, C1-C12 alkoxy, C3-C12 cycloalkyl, C6-C14 aryl;

[0011] The dashed line indicates no connection or connection in the form of a carbon-carbon single bond.

[0012] The organic light-emitting compound suitable for solution processing provided by this application, through the spiro structure and the peripherally modified R 1 and R 2 groups spatially wrap the core light-emitting unit, thereby reducing intermolecular quenching; due to the steric hindrance effect of the spiro structure and the peripherally modified groups, the solution processability of the organic light-emitting compound of this application is improved, so that the organic electroluminescent device prepared by the solution processing method obtains good device performance.

[0013] The organic light-emitting compound suitable for solution processing described above, wherein the organic light-emitting compound is any one of compounds BN-1 to BN-184.

[0014] A preparation method of an organic light-emitting compound suitable for solution processing as described above, wherein it is any of the following preparation methods:

[0015] The first preparation method:

[0016] Dissolve the first raw material, the second raw material and cesium carbonate in DMF, heat to 155 °C under nitrogen and stir for 8 hours; after the reaction is completed and cooled to room temperature, pour it into ice water, filter to obtain the precipitated solid, and recrystallize with dichloromethane and methanol to finally obtain the first solid product;

[0017] Place the first solid product in a container, dissolve it with ultra-dry tert-butylbenzene, displace nitrogen, and add tert-butyllithium dropwise at -30 °C, then react at 70 °C for 2 h; after cooling to -30 °C, add BBr3 dropwise, and react at room temperature for 1 h; after cooling to 0 °C, add DIPEA dropwise and reflux at 160 °C overnight; after the reaction is completed, quench with a mixture of H2O and MeOH with a volume ratio of 1:1 under an ice bath, extract with dichloromethane and water, and separate by column chromatography after evaporation to obtain the organic light-emitting compound.

[0018] In the first preparation method, the molar ratio of the first raw material, the second raw material to the cesium carbonate is 1:2.4:3, and the molar ratio of the first solid product, the tert-butyllithium, the BBr3 to the DIPEA is 1:1.2:2:2;

[0019] The second preparation method:

[0020] The first raw material, the second raw material and sodium tert-butoxide are dissolved in PhMe2, and after replacing nitrogen, tri-tert-butylphosphine tetrafluoroborate and palladium acetate are added, and the mixture is heated to 150° C. and reacted overnight; after the reaction is completed and cooled to room temperature, the reaction system is extracted with dichloromethane and water, and the organic phase is dried by spin drying and separated by column chromatography to obtain a first solid product;

[0021] The first solid product is placed in a container, dissolved with ultra-dry tert-butylbenzene, tert-butyl lithium is added dropwise at -30°C after replacing nitrogen, and then reacted at 70°C for 2h; BBr3 is added dropwise after cooling to -30°C, and reacted for 1h after returning to room temperature; DIPEA is added dropwise after cooling to 0°C, and refluxed at 160°C overnight; after the reaction is completed, the mixture is quenched with a mixture of H2O and MeOH in a volume ratio of 1:1 in an ice-water bath, extracted with dichloromethane and water, and separated by column chromatography after spin drying to obtain the organic light-emitting compound;

[0022] In the second preparation method, the molar ratio of the first raw material, the second raw material, the sodium tert-butoxide, the tri-tert-butylphosphine tetrafluoroborate and the palladium acetate is 1:2.4:3:0.1:0.1, and the molar ratio of the first solid product, the tert-butyl lithium, the BBr3 and the DIPEA is 1:1.2:2:2;

[0023] The third preparation method:

[0024] The first raw material, the second raw material and cesium carbonate are dissolved in DMF, and the mixture is heated to 70° C. under nitrogen and reacted overnight; after the reaction is completed and cooled to room temperature, the mixture is poured into ice water, and the precipitated solid is obtained by suction filtration, and extracted with dichloromethane and water, and the solid is separated by column chromatography after being spin-dried to obtain the first solid product;

[0025] The first solid product, the third raw material and cesium carbonate were dissolved in DMF, heated to 155° C. under nitrogen and stirred for 8 hours; after the reaction was completed and cooled to room temperature, the mixture was poured into ice water, filtered to obtain the precipitated solid, and recrystallized using dichloromethane and methanol to obtain a second solid product;

[0026] The second solid product is placed in a container, dissolved with ultra-dry tert-butylbenzene, tert-butyl lithium is added dropwise at -30°C after replacing nitrogen, and then reacted at 70°C for 2 hours; BBr3 is added dropwise after cooling to -30°C, and reacted for 1 hour after returning to room temperature; DIPEA is added dropwise after cooling to 0°C, and refluxed at 160°C overnight; after the reaction is completed, the product is quenched with a mixture of H2O and MeOH in a volume ratio of 1:1 in an ice-water bath, extracted with dichloromethane and water, and separated by column chromatography after spin drying to obtain the organic light-emitting compound.

[0027] In the third preparation method, the molar ratio among the first raw material, the second raw material and the cesium carbonate added for the first time is 2:1:1.5, the molar ratio among the first solid product, the third raw material and the cesium carbonate added for the second time is 1:1.2:1.5, and the molar ratio among the second solid product, the tert-butyllithium, the BBr3 and the DIPEA is 1:1.2:2:2;

[0028] Fourth preparation method:

[0029] Dissolve the first raw material, the second raw material and sodium tert-butoxide in PhMe2, evacuate and replace with nitrogen, then add tris(tert-butyl)phosphine tetrafluoroborate and palladium acetate, and heat to 150 °C for overnight reaction; after the reaction is completed and cooled to room temperature, extract the reaction system with dichloromethane and water, rotary evaporate the organic phase and then separate by column chromatography to obtain the first solid product;

[0030] Dissolve the first solid product, the third raw material and cesium carbonate in DMF, heat to 155 °C under nitrogen atmosphere and stir for 8 hours; after the reaction is completed and cooled to room temperature, pour it into ice water, filter to obtain the precipitated solid, and recrystallize with dichloromethane and methanol to obtain the second solid product;

[0031] Place the second solid product in a container, dissolve it with ultra-dry tert-butylbenzene, evacuate and replace with nitrogen, then add tert-butyllithium dropwise at -30 °C, and then react at 70 °C for 2 h; after cooling to -30 °C, add BBr3 dropwise, react at room temperature for 1 h after restoration; after cooling to 0 °C, add DIPEA dropwise and reflux at 160 °C overnight; after the reaction is completed, quench with a mixture of H2O and MeOH with a volume ratio of 1:1 under an ice bath, extract with dichloromethane and water, rotary evaporate and then separate by column chromatography to obtain the organic light-emitting compound.

[0032] In the fourth preparation method, the molar ratio among the first raw material, the second raw material, the sodium tert-butoxide, the tris(tert-butyl)phosphine tetrafluoroborate and the palladium acetate is 1:1.2:1.5:0.1:0.1, the molar ratio among the first solid product, the third raw material and the cesium carbonate is 1:1.2:1.5, and the molar ratio among the second solid product, the tert-butyllithium, the BBr3 and the DIPEA is 1:1.2:2:2;

[0033] Fifth preparation method:

[0034] Dissolve the first raw material, the second raw material and sodium tert-butoxide in PhMe2, evacuate and replace with nitrogen, then add tris(tert-butyl)phosphine tetrafluoroborate and palladium acetate, and heat to 120 °C for 3 h; after the reaction is completed and cooled to room temperature, extract the reaction system with dichloromethane and water, rotary evaporate the organic phase and then separate by column chromatography to obtain the first solid product;

[0035] The first solid product, the third raw material and sodium tert-butoxide are dissolved in PhMe2, and after replacing nitrogen, tri-tert-butylphosphine tetrafluoroborate and palladium acetate are added, and the mixture is heated to 150° C. and reacted overnight; after the reaction is completed and cooled to room temperature, the reaction system is extracted with dichloromethane and water, and the organic phase is spin-dried and separated by column chromatography to obtain a second solid product;

[0036] The second solid product is placed in a container, dissolved with ultra-dry tert-butylbenzene, tert-butyl lithium is added dropwise at -30°C after replacing nitrogen, and then reacted at 70°C for 2h; BBr3 is added dropwise after cooling to -30°C, and reacted for 1h after returning to room temperature; DIPEA is added dropwise after cooling to 0°C, and refluxed at 160°C overnight; after the reaction is completed, the mixture is quenched with a mixture of H2O and MeOH in a volume ratio of 1:1 in an ice-water bath, extracted with dichloromethane and water, and the organic phase is spin-dried and separated by column chromatography to obtain the organic light-emitting compound;

[0037] In the fifth preparation method, the molar ratio of the first raw material, the second raw material, the sodium tert-butoxide, the tri-tert-butylphosphine tetrafluoroborate and the palladium acetate is 2:1:1.2:0.05:0.05, the molar ratio of the first solid product, the third raw material, the sodium tert-butoxide, the tri-tert-butylphosphine tetrafluoroborate and the palladium acetate is 1:1.2:1.5:0.1:0.1, and the molar ratio of the second solid product, the tert-butyl lithium, the BBr3 and the DIPEA is 1:1.2:2:2.

[0038] The method for preparing an organic light-emitting compound suitable for solution processing, wherein the first raw material is any one of compounds A-1 to A-7.

[0039] In the method for preparing an organic light-emitting compound suitable for solution processing, the second raw material and the third raw material are selected from the same range of raw materials, and are any one of compounds B-1 to B-26.

[0040] An organic electroluminescent device comprises an anode, a cathode and an organic thin film layer arranged between the anode and the cathode, wherein the organic thin film layer comprises a light-emitting layer, the light-emitting layer is prepared by a solution processing method, the light-emitting layer comprises a light-emitting material and a main material, and the light-emitting material adopts the organic light-emitting compound suitable for solution processing as described above.

[0041] The organic electroluminescent device, wherein the main material is mCPBC.

[0042] The organic electroluminescent device, wherein, in the light-emitting layer, the light-emitting material accounts for 0.5-30% by mass, and the remainder is the host material.

[0043] The organic electroluminescent device described above, wherein the organic thin film layer further includes a first hole transport layer, a second hole transport layer, a first electron transport layer, a second electron transport layer, and an electron injection layer;

[0044] The anode, the first hole transport layer, the second hole transport layer, the light emitting layer, the first electron transport layer, the second electron transport layer, the electron injection layer, and the cathode are sequentially arranged from bottom to top.

[0045] The organic electroluminescent device described above, wherein the first hole transport layer is prepared from a mixed solution of PEDOT:PSS and PFI with a mass ratio of 1:5;

[0046] The second hole transport layer is prepared from poly-HTL;

[0047] The first electron transport layer is prepared from DMFBD-TRZ;

[0048] The second electron transport layer is prepared from Na-An-BI;

[0049] The electron injection layer is prepared from Liq.

[0050] Beneficial effects: The solution-processable organic light-emitting compound provided by the present application wraps the core light-emitting unit in space through the spiro structure and the peripherally modified R 1 and R 2 groups, thereby reducing intermolecular quenching; due to the steric hindrance effect of the spiro structure and the peripherally modified groups, the solution processability of the organic light-emitting compound of the present application is improved, so that the organic electroluminescent device prepared by the solution process method has good device performance. In the solution of the present application, the maximum external quantum efficiency of the device electroluminescence of the organic electroluminescent device prepared by using the organic light-emitting compound of the present application reaches more than 30%, and the device life (T50, hours) reaches more than 800 hours. Description of the Drawings

[0051] Figure 1 It is a schematic diagram of the device structure involved in the device embodiment and the device comparative example in the present application.

[0052] Label description: 1. ITO anode; 2. First hole transport layer; 3. Second hole transport layer; 4. Light emitting layer; 5. First electron transport layer; 6. Second electron transport layer; 7. Electron injection layer; 8. Metal cathode. Detailed Embodiments

[0053] This application provides an organic light-emitting compound suitable for solution processing, a preparation method thereof, and an organic electroluminescent device. To make the purpose, technical solution, and effects of this application clearer and more definite, the following further details this application. It should be understood that the specific embodiments described herein are only used to explain this application and are not used to limit this application.

[0054] This application provides an organic light-emitting compound suitable for solution processing, and its structural formula is shown in formula (I):

[0055]

[0056] Wherein, R1 and R2 are independently selected from C6-C30 aryl, C6-C18 aryl substituted by one or more R a substituted C6-C18 aryl, 5- to 18-membered heteroaryl, 5- to 18-membered heteroaryl substituted by one or more R a substituted carbazolyl, carbazolyl substituted by one or more R a substituted diphenylamino, diphenylamino substituted by one or more R a substituted diphenylamino;

[0057] R3, R4, and R5 are independently selected from hydrogen, deuterium, C3-C20 cycloalkyl, C6-C30 aryl, C6-C18 aryl substituted by one or more R a substituted C6-C18 aryl, 5- to 18-membered heteroaryl;

[0058] R a Each occurrence is independently deuterium, fluorine, C1-C12 alkyl, C1-C12 alkoxy, C3-C12 cycloalkyl, C6-C14 aryl;

[0059] The dotted line indicates not connected, or connected in the form of a carbon-carbon single bond.

[0060] The structure of the organic light-emitting compound of this application mainly has the following two characteristics:

[0061] (1) The spiro structure at the para position of boron (B); (2) The R on the periphery of the aromatic amine (carbazole, diphenylamino group) coordinated with boron 1 and R 2 are again substituted by aromatic amine.

[0062] In the solution of this application, the spiro structure and the peripherally modified R 1 and R 2The group wraps the core light-emitting unit in space, thereby reducing intermolecular quenching; due to the steric hindrance effect of the spiro structure and the peripheral modification group, the solution processability of the organic light-emitting compound of the present application is improved, so that the organic electroluminescent device prepared by the solution process method obtains good device performance. In the solution of the present application, the maximum external quantum efficiency of the device electroluminescence of the organic electroluminescent device prepared by using the organic light-emitting compound of the present application reaches more than 30%, and the device life (T50, hours) reaches more than 800 hours.

[0063] Preferably, the organic light-emitting compound of the present application is any one of compounds BN-1 to BN-184:

[0064]

[0065]

[0066]

[0067]

[0068]

[0069]

[0070]

[0071]

[0072]

[0073] The present application also provides an organic electroluminescent device, including an anode, a cathode, and an organic thin film layer disposed between the anode and the cathode. The organic thin film layer includes a light-emitting layer, the light-emitting layer is prepared by a solution process method, the light-emitting layer includes a light-emitting material and a host material, and the light-emitting material uses the above-mentioned organic light-emitting compound.

[0074] In the solution of the embodiment of the present application, the host material used is mCPBC.

[0075] Further, in the light-emitting layer, by mass percentage, the light-emitting material accounts for 0.5 to 30%, and the balance is the host material.

[0076] Further, in the solution of the embodiment of the present application, the organic thin film layer further includes a first hole transport layer, a second hole transport layer, a first electron transport layer, a second electron transport layer, and an electron injection layer;

[0077] The anode, the first hole transport layer, the second hole transport layer, the light-emitting layer, the first electron transport layer, the second electron transport layer, the electron injection layer and the cathode are sequentially arranged from bottom to top.

[0078] This application also provides a synthetic route for the above-mentioned organic light-emitting compound.

[0079] In some embodiments of this application, the raw materials used to synthesize the organic light-emitting compound shown in formula (I) include a first raw material and a second raw material.

[0080] When synthesizing the organic light-emitting compound shown in formula (I) using the first raw material and the second raw material, there are two preparation routes.

[0081] When the first raw material is A-1 to A-2 and the carbazole derivative raw material reacting with the two fluorine atoms in the first raw material is the same, the first preparation route is adopted.

[0082] The first preparation route includes the following steps:

[0083] Dissolve the first raw material, the second raw material and cesium carbonate in DMF (N,N-dimethylformamide), heat to 155 °C under nitrogen and stir for 8 hours; after the reaction is completed and cooled to room temperature, pour it into ice water, filter by suction to obtain the precipitated solid, and recrystallize with dichloromethane and methanol to finally obtain the first solid product;

[0084] Place the above-mentioned first solid product in a three-necked flask, dissolve it with ultra-dry tert-butylbenzene, displace nitrogen, and dropwise add tert-butyllithium at -30 °C, then react at 70 °C for 2 h; cool to -30 °C and dropwise add BBr3 (boron tribromide), react at room temperature for 1 h after restoring to room temperature; cool to 0 °C and dropwise add DIPEA (N,N-diisopropylethylamine), reflux overnight at 160 °C; after the reaction is completed, quench with a H2O / MeOH mixture (volume ratio 1:1) under an ice bath, extract with dichloromethane and water, spin dry and separate by column chromatography to obtain the second solid product, which is the organic light-emitting compound of this application.

[0085] Among them, the molar ratio of the first raw material, the second raw material to cesium carbonate is 1:2.4:3, and the molar ratio of the first solid product, tert-butyllithium, BBr3 to DIPEA is 1:1.2:2:2.

[0086] When the first raw material is A-3 to A-4 and the diphenylamine derivative raw material reacting with the two bromine atoms in the first raw material is the same, the second preparation route is adopted.

[0087] The second preparation route includes the following steps:

[0088] Dissolve the first raw material, the second raw material and sodium tert-butoxide in PhMe2 (xylene). After purging with nitrogen, add tris(tert-butyl)phosphine tetrafluoroborate and palladium acetate, and heat to 150 °C for reaction overnight. After the reaction is completed and cooled to room temperature, extract the reaction system with dichloromethane and water. After the organic phase is dried by rotation, separate by column chromatography to obtain the first solid product;

[0089] Place the above-mentioned first solid product in a three-necked flask, dissolve it with ultra-dry tert-butylbenzene, purge with nitrogen, and then add tert-butyllithium dropwise at -30 °C. Subsequently, react at 70 °C for 2 h. After cooling to -30 °C, add BBr3 dropwise, and react at room temperature for 1 h. After cooling to 0 °C, add DIPEA dropwise and reflux at 160 °C overnight. After the reaction is completed, quench with a H2O / MeOH mixture under an ice-water bath, extract with dichloromethane and water, and separate by column chromatography after drying by rotation to obtain the second solid product, which is the organic light-emitting compound of this application.

[0090] Among them, the molar ratio of the first raw material, the second raw material, sodium tert-butoxide, tris(tert-butyl)phosphine tetrafluoroborate and palladium acetate is 1:2.4:3:0.1:0.1;

[0091] The molar ratio of the first solid product, tert-butyllithium, BBr3 and DIPEA is 1:1.2:2:2.

[0092] In some embodiment schemes, the raw materials used for synthesizing the organic light-emitting compound shown in formula (I) further include the first raw material, the second raw material and the third raw material. When synthesizing the organic light-emitting compound shown in formula (I) using the first raw material, the second raw material and the third raw material, there are three preparation routes.

[0093] When the carbazole derivatives reacting with the two fluorine atoms in the first raw material (A1-A2) are different, adopt the method of controlling the reactant ratio to make the two fluorine atoms react with different carbazole derivatives in sequence, and adopt the first preparation route. At this time, the second carbazole derivative reacting with the second fluorine atom is the third raw material. Specifically, the first preparation route includes the following steps:

[0094] Dissolve the first raw material, the second raw material and cesium carbonate in DMF, and heat to 70 °C for reaction overnight under nitrogen. After the reaction is completed and cooled to room temperature, pour it into ice water, filter to obtain the precipitated solid, extract with dichloromethane and water, and separate by column chromatography after drying by rotation to obtain the first solid product;

[0095] Dissolve the above-mentioned first solid product, the third raw material and cesium carbonate in DMF, heat to 155 °C and stir for 8 hours under nitrogen. After the reaction is completed and cooled to room temperature, pour it into ice water, filter to obtain the precipitated solid, and recrystallize with dichloromethane and methanol to finally obtain the second solid product;

[0096] Place the above-mentioned second solid product in a three-necked flask, dissolve it with ultra-dry tert-butylbenzene, displace nitrogen, and then add tert-butyllithium dropwise at -30°C. Subsequently, react at 70°C for 2 h; after cooling to -30°C, add BBr3 dropwise, and react for 1 h after returning to room temperature; after cooling to 0°C, add DIPEA dropwise, and reflux overnight at 160°C; after the reaction is completed, quench with a H2O / MeOH mixture under an ice-water bath, extract with dichloromethane and water, and after rotary evaporation, separate by column chromatography to obtain the third solid product, which is the organic light-emitting compound of the present application.

[0097] Among them, the molar ratio of the first raw material, the second raw material, and the cesium carbonate added for the first time is 2:1:1.5, the molar ratio of the first solid product, the third raw material, and the cesium carbonate added for the second time is 1:1.2:1.5, and the molar ratio of the second solid product, tert-butyllithium, BBr3, and DIPEA is 1:1.2:2:2.

[0098] When the first raw material (A-5 to A-7) participates in the reaction, first react the diphenylamine derivative with a bromine atom to obtain the first solid product, and then use the carbazole derivative to carry out a nucleophilic substitution reaction with a fluorine atom to obtain the second solid product. At this time, the second preparation route is adopted. At this time, the carbazole derivative reacting with the fluorine atom is the third raw material. Specifically, the second preparation route includes the following steps:

[0099] Dissolve the first raw material, the second raw material, and sodium tert-butoxide in PhMe2 (xylene), displace nitrogen, and then add tris(tert-butyl)phosphine tetrafluoroborate and palladium acetate, and heat to 150°C to react overnight; after the reaction is completed and cooled to room temperature, extract the reaction system with dichloromethane and water, rotary evaporate the organic phase, and separate by column chromatography to obtain the first solid product;

[0100] Dissolve the above-mentioned first solid product, the third raw material, and cesium carbonate in DMF, heat to 155°C under nitrogen and maintain stirring for 8 hours; after the reaction is completed and cooled to room temperature, pour it into ice water, filter to obtain the precipitated solid, and recrystallize with dichloromethane and methanol to finally obtain the second solid product;

[0101] Place the above-mentioned second solid product in a three-necked flask, dissolve it with ultra-dry tert-butylbenzene, displace nitrogen, and then add tert-butyllithium dropwise at -30°C. Subsequently, react at 70°C for 2 h. After cooling to -30°C, add BBr3 dropwise, and react for 1 h after returning to room temperature; after cooling to 0°C, add DIPEA dropwise, and reflux overnight at 160°C; after the reaction is completed, quench with a H2O / MeOH mixture under an ice-water bath, extract with dichloromethane and water, and after rotary evaporation, separate by column chromatography to obtain the third solid product, which is the organic light-emitting compound of the present application.

[0102] Among them, the molar ratio of the first raw material, the second raw material, sodium tert-butoxide, tris(tert-butyl)phosphine tetrafluoroborate, and palladium acetate is 1:1.2:1.5:0.1:0.1;

[0103] The molar ratio among the first solid product, the third raw material, and cesium carbonate is 1:1.2:1.5;

[0104] The molar ratio among the second solid product, tert-butyllithium, BBr3, and DIPEA is 1:1.2:2:2.

[0105] When the diphenylamine derivatives with which the two bromine atoms in the first raw material (A3-A4) react are different, a method of controlling the proportion of reactants is adopted to make the two bromine atoms react with different diphenylamine derivatives successively, and the third preparation route is adopted. At this time, the second diphenylamine derivative that reacts with the second bromine atom is the third raw material. Specifically, the third preparation route includes the following steps:

[0106] Dissolve the first raw material, the second raw material, and sodium tert-butoxide in PhMe2, evacuate and replace with nitrogen, then add tris(tert-butyl)phosphine tetrafluoroborate and palladium acetate, and heat to 120 °C for reaction for 3 h; after the reaction is completed and cooled to room temperature, extract the reaction system with dichloromethane and water, spin-dry the organic phase and separate by column chromatography to obtain the first solid product;

[0107] Dissolve the above-mentioned first solid product, the third raw material, and sodium tert-butoxide in PhMe2, evacuate and replace with nitrogen, then add tris(tert-butyl)phosphine tetrafluoroborate and palladium acetate, and heat to 150 °C for reaction overnight; after the reaction is completed and cooled to room temperature, extract the reaction system with dichloromethane and water, spin-dry the organic phase and separate by column chromatography to obtain the second solid product;

[0108] Place the second solid product in a three-necked flask, dissolve it with ultra-dry tert-butylbenzene, displace nitrogen, then add tert-butyllithium dropwise at -30 °C, and then react at 70 °C for 2 h; cool to -30 °C and then add BBr3 dropwise, restore to room temperature and react for 1 h; cool to 0 °C and then add DIPEA dropwise, reflux at 160 °C overnight; after the reaction is completed, quench with a H2O / MeOH mixture under an ice-water bath, extract with dichloromethane and water, spin-dry the organic phase and separate by column chromatography to obtain the third solid product, which is the organic light-emitting compound of this application.

[0109] Among them, the molar ratio among the first raw material, the second raw material, sodium tert-butoxide, tris(tert-butyl)phosphine tetrafluoroborate, and palladium acetate is 2:1:1.2:0.05:0.05;

[0110] The molar ratio among the first solid product, the third raw material, sodium tert-butoxide, tris(tert-butyl)phosphine tetrafluoroborate, and palladium acetate is 1:1.2:1.5:0.1:0.1;

[0111] The molar ratio among the second solid product, tert-butyllithium, BBr3, and DIPEA is 1:1.2:2:2.

[0112] In the preparation method of the present application, the first raw material is any one of the following compounds A-1 to A-7:

[0113]

[0114]

[0115] The second raw material and the third raw material are each any one of the following compounds B-1 to B-26:

[0116]

[0117]

[0118] The present application is further illustrated by the following synthesis examples.

[0119] Synthesis Example 1

[0120] The specific synthesis route and characterization test data of compound BN-51 are as follows:

[0121]

[0122] Synthesis and characterization of compound BN-51-A:

[0123] The first raw material A-1 (10.0 mmol, 1 eq, 3.88 g), the second raw material B-3 (24.0 mmol, 2.4 eq, 17.33 g) and cesium carbonate (CsCO3) 30.0 mmol, 3 eq, 9.75 g) were dissolved in 60.0 mL of DMF (N,N-dimethylformamide), and heated to 155 °C under nitrogen and stirred for 8 hours. After the reaction was completed and cooled to room temperature, it was poured into 500 mL of ice water, and the precipitated solid was obtained by suction filtration. Recrystallization was carried out using dichloromethane and methanol, and finally 17.00 g of white solid BN-51-A was obtained, with a yield of 95%. It was confirmed to be the target product by mass spectrometry and elemental analysis tests. Moldi-MS: 1792.87 (calculated value: 1792.90). Elemental analysis: C, 86.41; H, 6.93; N, 4.70, theoretical value: C, 86.42; H, 6.92Cl, 1.98; N, 4.69.

[0124] Synthesis and characterization of compound BN-51:

[0125] BN-51-A (10 mmol, 1 eq, 17.9 g) was placed in a 100 mL three-necked flask and dissolved in 30 mL of ultradry tert-butylbenzene. After displacing nitrogen, tert-butyllithium (1.2 eq, 2.5 M, 4.8 mL) was added dropwise at -30 °C, and then the reaction was carried out at 70 °C for 2 h. After cooling to -30 °C, BBr3 (boron tribromide) (2 eq, 20 mmol, 1.93 mL) was added dropwise. After restoring to room temperature, the reaction was carried out for 1 h. After cooling to 0 °C, DIPEA (N,N-diisopropylethylamine) (2 eq, 20 mmol, 3.49 mL) was added dropwise, and the mixture was refluxed overnight at 160 °C. After the reaction was completed, the reaction was quenched with 20 mL of a H2O / MeOH (volume ratio 1:1) mixture under an ice-water bath, extracted with dichloromethane and water, dried by evaporation, and separated by column chromatography to obtain 3.53 g of a yellow solid product with a yield of 20%. It was confirmed to be the target product by mass spectrometry and elemental analysis. Moldi-MS: 1766.20 (calculated value: 1766.24). Elemental analysis: C, 87.70; H, 6.92; N, 4.75, theoretical values: C, 87.72; H, 6.91; B, 0.61; N, 4.76.

[0126] Synthesis Example 2

[0127] The specific synthesis route and characterization test data of compound BN-53 are as follows:

[0128]

[0129] Synthesis and Characterization of Compound BN-53-A

[0130] The first raw material A-1 (20.0 mmol, 2 eq, 7.78 g), the second raw material B-3 (10.0 mmol, 1 eq, 7.22 g) and cesium carbonate (15.0 mmol, 1.5 eq, 4.88 g) were dissolved in 50.0 mL of DMF, and the reaction was carried out at 70 °C overnight under a nitrogen atmosphere. After the reaction was completed and cooled to room temperature, it was poured into 1 L of ice water, and the precipitated solid was obtained by suction filtration, extracted with dichloromethane and water, dried by evaporation, and separated by column chromatography to obtain 5.45 g of a white solid product BN-53-A with a yield of 50%. It was confirmed to be the target product by mass spectrometry and elemental analysis. Moldi-MS: 1090.85 (calculated value: 1090.87). Elemental analysis: C, 84.80; H, 6.36; N, 3.84, theoretical values: C, 84.78; H, 6.38; Cl, 3.25; F, 1.74; N, 3.85.

[0131] Synthesis and Characterization of Compound BN-53-B

[0132] BN-53-A (10.0 mmol, 1 eq, 10.91 g), the third raw material B-4 (12 mmol, 1.2 eq, 9.63 g) and cesium carbonate (15.0 mmol, 1.5 eq, 4.88 g) were dissolved in 50.0 mL of DMF. Under nitrogen atmosphere, it was heated to 155 °C and stirred for 8 hours. After the reaction was completed and cooled to room temperature, it was poured into 500 mL of ice water. The precipitated solid was obtained by suction filtration and recrystallized with dichloromethane and methanol. Finally, 17.8 g of white solid BN-53-B was obtained with a yield of 95%. It was confirmed as the target product by mass spectrometry and elemental analysis. Moldi-MS: 1872.84 (calculated value: 1872.86). Elemental analysis: C, 87.85; H, 5.77; N, 4.51, theoretical values: C, 87.86; H, 5.76; Cl, 1.89; N, 4.49.

[0133] Synthesis and characterization of compound BN-53:

[0134] BN-53-B (10 mmol, 1 eq, 18.7 g) was placed in a 100 mL three-necked flask and dissolved in 30 mL of super-dry tert-butylbenzene. After replacing nitrogen, tert-butyllithium (1.2 eq, 2.5 M, 4.8 mL) was added dropwise at -30 °C, and then the reaction was carried out at 70 °C for 2 h. After cooling to -30 °C, BBr3 (2 eq, 20 mmol, 1.93 mL) was added dropwise. After returning to room temperature, the reaction was carried out for 1 h. After cooling to 0 °C, DIPEA (2 eq, 20 mmol, 3.49 mL) was added dropwise and refluxed overnight at 160 °C. After the reaction was completed, it was quenched with 20 mL of a H2O / MeOH (volume ratio 1:1) mixture under an ice-water bath, extracted with dichloromethane and water, and the solvent was evaporated and separated by column chromatography to obtain 3.32 g of yellow solid product with a yield of 18%. It was confirmed as the target product by mass spectrometry and elemental analysis. Moldi-MS: 1846.23 (calculated value: 1846.20). Elemental analysis: C, 89.15; H, 5.72; N, 4.53, theoretical values: C, 89.13; H, 5.73; B, 0.59; N, 4.55.

[0135] Synthesis Example 3

[0136] The specific synthesis route and characterization test data of compound BN-150 are as follows:

[0137]

[0138] Synthesis and characterization of compound BN-150-A:

[0139] The first raw material A-5 (10.0mmol, 1eq, 4.50g), the second raw material B-18 (12.0mmol, 1.2eq, 8.74g) and sodium tert-butoxide (15.0mmol, 1.5eq, 1.44g) were dissolved in 20.0mL PhMe2 (xylene), and tri-tert-butylphosphine tetrafluoroborate (1mmol, 0.1eq, 290mg) and palladium acetate (1mmol, 0.1eq, 225mg) were added after nitrogen was replaced, and heated to 150°C for overnight reaction. After the reaction was completed and cooled to room temperature, the reaction system was extracted with dichloromethane and water, and the organic phase was spin-dried and separated by column chromatography to obtain white solid BN-150-A9.9g with a yield of 90%. It was confirmed as the target product by mass spectrometry and elemental analysis. Moldi-MS: 1096.90 (calculated value: 1096.92). Elemental analysis: C, 84.30; H, 6.90; N, 3.85, theoretical value: C, 84.31; H, 6.89; Cl, 3.23; F, 1.73; N, 3.83.

[0140] Synthesis and characterization of compound BN-150-B:

[0141] BN-150-A (10.0mmol, 1eq, 10.97g), the third raw material B-22 (12mmol, 1.2eq, 7.80g) and cesium carbonate (15.0mmol, 1.5eq, 4.88g) were dissolved in 50.0mL DMF, heated to 155°C under nitrogen and stirred for 8 hours. After the reaction was cooled to room temperature, it was poured into 500mL ice water, filtered to obtain the precipitated solid, and recrystallized from dichloromethane and methanol to finally obtain 16.40g of white solid BN-150-B with a yield of 95%. It was confirmed as the target product by mass spectrometry and elemental analysis. Moldi-MS: 1726.72 (calculated value: 1726.70). Elemental analysis: C, 86.97; H, 6.11; N, 4.85, theoretical value: C, 86.95; H, 6.13; Cl, 2.05; N, 4.87.

[0142] Synthesis and characterization of compound BN-150:

[0143] BN-150-B (10 mmol, 1 eq, 17.27 g) was placed in a 100 mL three-necked flask and dissolved in 30 mL of ultra-dry tert-butylbenzene. After displacing nitrogen, tert-butyllithium (1.2 eq, 2.5 M, 4.8 mL) was added dropwise at -30 °C, and then the reaction was carried out at 70 °C for 2 h. After cooling to -30 °C, BBr3 (2 eq, 20 mmol, 1.93 mL) was added dropwise. After returning to room temperature, the reaction was carried out for 1 h. After cooling to 0 °C, DIPEA (2 eq, 20 mmol, 3.49 mL) was added dropwise, and the mixture was refluxed overnight at 160 °C. After the reaction was completed, the reaction was quenched with 20 mL of a H2O / MeOH (volume ratio 1:1) mixture under an ice-water bath. The mixture was extracted with dichloromethane and water, and after evaporation to dryness, column chromatography was used for separation to obtain 2.89 g of a yellow solid product with a yield of 17%. It was confirmed to be the target product by mass spectrometry and elemental analysis. Moldi-MS: 1700.08 (calculated value: 1700.05). Elemental analysis: C, 88.30; H, 6.13; N, 4.92, theoretical values: C, 88.31; H, 6.11; B, 0.64; N, 4.94.

[0144] Synthesis Example 4

[0145] The specific synthesis route and characterization test data of compound BN-156 are as follows:

[0146]

[0147] Synthesis and Characterization of Compound BN-156-A:

[0148] The first raw material A-3 (10.0 mmol, 1 eq, 5.11 g), the second raw material B-19 (24.0 mmol, 2.4 eq, 19.40 g) and sodium tert-butoxide (30.0 mmol, 3 eq, 2.89 g) were dissolved in 20.0 mL of PhMe2. After displacing nitrogen, tris(tert-butyl)phosphine tetrafluoroborate (1 mmol, 0.1 eq, 290 mg) and palladium acetate (1 mmol, 0.1 eq, 225 mg) were added, and the mixture was heated to 150 °C and reacted overnight. After the reaction was completed and cooled to room temperature, the reaction system was extracted with dichloromethane and water. After evaporation of the organic phase to dryness, column chromatography was used for separation to obtain 17.68 g of white solid BN-156-A with a yield of 90%. It was confirmed to be the target product by mass spectrometry and elemental analysis. Moldi-MS: 1964.89 (calculated value: 1964.91). Elemental analysis: C, 88.62; H, 5.29; N, 4.26, theoretical values: C, 88.63; H, 5.28; Cl, 1.80; N, 4.28.

[0149] Synthesis and Characterization of Compound BN-156:

[0150] BN-156-A (10 mmol, 1 eq, 19.65 g) was placed in a 100 mL three-necked flask and dissolved in 30 mL of ultra-dry tert-butylbenzene. After displacing nitrogen, tert-butyllithium (1.2 eq, 2.5 M, 4.8 mL) was added dropwise at -30 °C, and then the reaction was carried out at 70 °C for 2 h. After cooling to -30 °C, BBr3 (2 eq, 20 mmol, 1.93 mL) was added dropwise, and the reaction was continued at room temperature for 1 h. After cooling to 0 °C, DIPEA (2 eq, 20 mmol, 3.49 mL) was added dropwise, and the mixture was refluxed at 160 °C overnight. After the reaction was completed, the reaction was quenched with 20 mL of a H2O / MeOH (volume ratio 1:1) mixture under an ice-water bath, and the mixture was extracted with dichloromethane and water. The organic phase was dried by rotary evaporation and then separated by column chromatography to obtain 3.87 g of a yellow solid product with a yield of 20%. The product was confirmed to be the target product by mass spectrometry and elemental analysis. Moldi-MS: 1938.23 (calculated value: 1938.26). Elemental analysis: C, 89.82; H, 5.26; N, 4.33, theoretical values: C, 89.85; H, 5.25; B, 0.56; N, 4.34.

[0151] Synthesis Example 5

[0152] The specific synthesis route and characterization test data of compound BN-167 are as follows:

[0153]

[0154] Synthesis and Characterization of Compound BN-167-A:

[0155] The first raw material A-4 (20.0 mmol, 2 eq, 16.30 g), the second raw material B-25 (10.0 mmol, 1 eq, 6.51 g) and sodium tert-butoxide (12.0 mmol, 1.2 eq, 1.15 g) were dissolved in 20.0 mL of PhMe2. After displacing nitrogen, tris(tert-butyl)phosphine tetrafluoroborate (0.5 mmol, 0.05 eq, 145 mg) and palladium acetate (0.5 mmol, 0.05 eq, 113 mg) were added, and the mixture was heated to 120 °C for 3 h. After the reaction was completed and cooled to room temperature, the reaction system was extracted with dichloromethane and water. The organic phase was dried by rotary evaporation and then separated by column chromatography to obtain 8.32 g of white solid BN-167-A with a yield of 60%. The product was confirmed to be the target product by mass spectrometry and elemental analysis. Moldi-MS: 1385.92 (calculated value: 1385.95). Elemental analysis: C, 84.04; H, 4.60; N, 3.05, theoretical values: C, 84.06; H, 4.58; Br, 5.77; Cl, 2.56; N, 3.03.

[0156] Synthesis and Characterization of Compound BN-167-B:

[0157] BN-167-A (10.0mmol, 1eq, 13.86g), the third raw material B-20 (12.0mmol, 1.2eq, 19.36g) and sodium tert-butoxide (15mmol, 1.5eq, 1.45g) were dissolved in 20.0mL PhMe2, and tri-tert-butylphosphine tetrafluoroborate (1mmol, 0.1eq, 290mg) and palladium acetate (1mmol, 0.1eq, 225mg) were added after nitrogen was replaced, and heated to 150°C for overnight reaction. After the reaction was completed and cooled to room temperature, the reaction system was extracted with dichloromethane and water, and the organic phase was spin-dried and separated by column chromatography to obtain 26.30g of white solid BN-167-B with a yield of 90%. It was confirmed as the target product by mass spectrometry and elemental analysis. Moldi-MS: 2918.30 (calculated value: 2918.33). Elemental analysis: C, 87.64; H, 6.30; N, 4.81, theoretical value: C, 87.66; H, 6.32; Cl, 1.21; N, 4.80.

[0158] Synthesis and characterization of compound BN-167:

[0159] BN-167-B (10mmol, 1eq, 29.2g) was placed in a 100mL three-necked flask, and 40mL of ultra-dry tert-butylbenzene was dissolved. After replacing nitrogen, tert-butyl lithium (1.2eq, 2.5M, 4.8mL) was added dropwise at -30℃, and then reacted at 70℃ for 2h. After cooling to -30℃, BBr3 (2eq, 20mmol, 1.93mL) was added dropwise, and the mixture was returned to room temperature and reacted for 1h. After cooling to 0℃, DIPEA (2eq, 20mmol, 3.49mL) was added dropwise, and refluxed at 160℃ overnight. After the reaction was completed, quenched with 20mL of H2O / MeOH (volume ratio 1:1) mixture in an ice-water bath, extracted with dichloromethane and water, and the organic phase was spin-dried and separated by column chromatography to obtain 4.61g of yellow solid product with a yield of 16%. It was confirmed to be the target product by mass spectrometry and elemental analysis. Moldi-MS: 2891.65 (calculated value: 2891.67). Elemental analysis: C, 88.45; H, 6.30; N, 4.85, theoretical value: C, 88.47; H, 6.31; B, 0.37; N, 4.84.

[0160] Other organic light-emitting compounds were prepared according to similar synthesis methods as described above, and the products were verified by mass spectrometry and elemental analysis. The specific raw materials used for all organic light-emitting compounds, elemental analysis of the products (percentages of C, H and N in the compounds), and mass spectrometry molecular weight data are shown in Table 1.

[0161] Table 1

[0162]

[0163]

[0164]

[0165]

[0166] Device Examples and Device Comparative Examples

[0167] Some representative device examples and device comparative examples are given below. The molecular structures of some materials involved in the device examples and device comparative examples are as follows. Among them, PEDOT:PSS is a product of model AI4083 purchased from Heraeus, and PFI is Nafion purchased from sigma-aldrich TM Perfluorinated resin solution, poly-HTL was purchased from Xi'an Baolait

[0168]

[0169]

[0170] The device structures involved in the device examples and device comparative examples are as Figure 1 shown, including an ITO anode 1, a first hole transport layer 2, a second hole transport layer 3, a light-emitting layer 4, a first electron transport layer 5, a second electron transport layer 6, an electron injection layer 7, and a metal cathode 8 in sequence from bottom to top.

[0171] The preparation process of the organic light-emitting device prepared in the device example is as follows:

[0172] (1) Substrate treatment: Transparent ITO glass is used as the substrate material for preparing the organic light-emitting device. First, it is ultrasonically treated with 5% ITO cleaning solution for 30 min, and then ultrasonically washed with distilled water (twice), acetone (twice), and isopropanol (twice) in sequence. Finally, the ITO glass is stored in isopropanol. Before each use, the surface of the ITO glass is carefully wiped with acetone cotton balls and isopropanol cotton balls, dried after being rinsed with isopropanol, and then treated with plasma for 5 min for standby. The preparation of the organic light-emitting device is completed by combining spin coating and vacuum evaporation processes.

[0173] (2) Preparation of hole transport layer: PEDOT:PSS and PFI were formulated into a first hole transport layer mixture at a mass ratio of 1:5 by spin coating. 200 μL of the first hole transport layer mixture was dropped onto ITO glass and spin-coated at 3500 rpm for 40 s, and then annealed and dried at 150 °C for 15 min to form a first hole transport layer with a thickness of 60 nm. The second hole transport material poly-HTL was dissolved in chlorobenzene as a solvent to obtain a second hole transport layer solution with a concentration of 8 mg / ml. 100 μL of the second hole transport layer solution was dropped onto the above first hole transport layer and spin-coated at 1500 rpm for 60 s, and then annealed and dried at 100 °C for 1 h to form a second hole transport layer with a thickness of 15 nm.

[0174] (3) Preparation of light-emitting layer: The light-emitting compound BN-n (n = 1 - 184) and the host material mCPBC were dissolved in xylene (1 mg / mL) at a mass ratio of 2.0 wt%:98.0 wt%. After being fully stirred and completely dissolved, the organic light-emitting ink was obtained by filtering through a 0.22-micron microporous filter membrane. It was formed on the second hole transport layer by spin coating. Through a vacuum film-forming process, it was treated at normal pressure for 10 minutes, and then treated at room temperature for 5 minutes under a pressure condition of 10 Pa for drying and film-forming. After that, it was baked at 120 °C for 20 minutes to form a light-emitting layer with a thickness of 35 nm.

[0175] (4) Preparation of electron transport layer, electron injection layer and metal electrode: The first electron transport layer, the second electron transport layer, the electron injection layer and the metal electrode were prepared by evaporation. When the vacuum degree of the vacuum evaporation system reached below 5×10 -4 Pa, evaporation began. The deposition rate was measured by a Sains film thickness gauge. Using the vacuum evaporation process, a 10-nm-thick first electron transport layer DMFBD-TRZ, a 30-nm-thick second electron transport layer Na-An-BI, a 2-nm-thick electron injection layer Liq and a 100-nm-thick metal electrode Al were successively deposited on the light-emitting layer. Among them, the deposition rate of the organic material was The deposition rate of LiF was The deposition rate of Al was

[0176] Device Example 1-n (n = 1 - 98) was prepared through the above preparation process, and its device structure was specifically [ITO / PEDOT:PSS:PFI (60 nm) / Poly-HTL (15 nm) / EML (35 nm) / DMFBD-TRZ (10

[0177] nm) / Na-An-BI (30 nm) / Liq (2 nm) / Al (100 nm)].

[0178] Performance tests were carried out on device examples 1-n. Characteristics such as the current, voltage, luminance, and emission spectrum of the devices were synchronously tested using a Photo Research PR 655 spectral scanning luminance meter and a Keithley K 2400 digital source meter system. The performance tests of the devices were carried out at room temperature and in an ambient atmosphere. The external quantum efficiency (EQE) of the devices was calculated from the current density, luminance, and electroluminescence spectrum in combination with the visibility function under the condition that the emission was Lambertian distribution.

[0179] The performance data of the device examples are shown in Table 2. The device lifetime (T50, hours) in Table 2 refers to the time required for the luminance of the device to decrease to 50% of the initial luminance at a luminance of 300 cd / m 2 brightness.

[0180] Table 2

[0181]

[0182]

[0183]

[0184]

[0185] Device comparative examples D-m (m = 1 - 6)

[0186] The device structures in device comparative examples D-m (m = 1 - 6) are the same as those in the device examples, and the preparation processes are also the same. The only difference is that the organic light-emitting compounds used in the light-emitting layer are different. The organic light-emitting compounds in the device comparative examples are R-1 to R-10 respectively. The device structure of the device comparative examples is [ITO / PEDOT:PSS:PFI(60 nm) / Poly-HTL(15 nm) / EML(35 nm) / DMFBD-TRZ(10 nm) / Na-An-BI(30 nm) / Liq(2 nm) / Al(100 nm)].

[0187] Performance tests were carried out on device comparative examples D-m (m = 1 - 10). The performance data of the device comparative examples are shown in Table 3. The device lifetime (T50, hours) in Table 3 refers to the time required for the luminance of the device to decrease to 50% of the initial luminance at a luminance of 300 cd / m 2 brightness.

[0188] Table 3

[0189]

[0190]

[0191] Based on the data of the device embodiments (Table 2) and the device comparative example data (Table 3) above, it can be seen that compared with some already disclosed organic light-emitting compounds, the organic light-emitting compound of the present application shows obvious technical advantages. The maximum external quantum efficiency of the organic electroluminescent device prepared by using the organic light-emitting compound of the present application exceeds 30%, and the device life also exceeds 800 hours.

[0192] It should be understood that the application of the present application is not limited to the above examples. For those of ordinary skill in the art, improvements or transformations can be made according to the above description, and all such improvements and transformations should fall within the protection scope of the present application.

Claims

1. An organic light-emitting compound suitable for solution processing, characterized in that, Its structural formula is shown in Formula (I): Among them, R1 and R2 are independently selected from C6-C30 aryl, C6-C18 aryl substituted by one or more R a substituted C6-C18 aryl, 5- to 18-membered heteroaryl, one or more R a substituted 5- to 18-membered heteroaryl, carbazolyl, one or more R a substituted carbazolyl, diphenylamino, one or more R a substituted diphenylamino; R3, R4, and R5 are independently selected from hydrogen, deuterium, C3-C20 cycloalkyl, C6-C30 aryl, C6-C18 aryl substituted with one or more R a substituents, and 5- to 18-membered heteroaryl; R a Each occurrence is independently deuterium, fluorine, C1-C12 alkyl, C1-C12 alkoxy, C3-C12 cycloalkyl, or C6-C14 aryl; The dashed line indicates no connection or connection in the form of a carbon-carbon single bond.

2. The organic light-emitting compound suitable for solution processing according to claim 1, wherein The organic light-emitting compound is any one of Compounds BN-1 to BN-184:

3. A method for preparing an organic light-emitting compound suitable for solution processing as described in claim 1, characterized in that, It is any of the following preparation methods: The first preparation method: Dissolve the first raw material, the second raw material and cesium carbonate in DMF, heat to 155 °C under nitrogen conditions and stir for 8 hours; after the reaction is completed and cooled to room temperature, pour it into ice water, filter by suction to obtain the precipitated solid, and perform recrystallization with dichloromethane and methanol to finally obtain the first solid product; Place the first solid product in a container, dissolve it with ultra-dry tert-butylbenzene, displace nitrogen, and add tert-butyllithium dropwise at -30 °C, then react at 70 °C for 2 h; after cooling to -30 °C, add BBr3 dropwise, and react at room temperature for 1 h; after cooling to 0 °C, add DIPEA dropwise and reflux overnight at 160 °C; after the reaction is completed, quench with a mixture of H2O and MeOH with a volume ratio of 1:1 under an ice bath, extract with dichloromethane and water, spin dry and separate by column chromatography to obtain the organic light-emitting compound; In the first preparation method, the molar ratio between the first raw material, the second raw material and the cesium carbonate is 1:2.4:3, and the molar ratio between the first solid product, the tert-butyllithium, the BBr3 and the DIPEA is 1:1.2:2:2; The second preparation method: Dissolve the first raw material, the second raw material and sodium tert-butoxide in PhMe2, displace nitrogen, add tris(tert-butyl)phosphine tetrafluoroborate and palladium acetate, and heat to 150 °C for reaction overnight; after the reaction is completed and cooled to room temperature, extract the reaction system with dichloromethane and water, spin dry the organic phase and separate by column chromatography to obtain the first solid product; Place the first solid product in a container, dissolve it with ultra-dry tert-butylbenzene, displace nitrogen, and add tert-butyllithium dropwise at -30 °C, then react at 70 °C for 2 h; after cooling to -30 °C, add BBr3 dropwise, and react at room temperature for 1 h; after cooling to 0 °C, add DIPEA dropwise and reflux overnight at 160 °C; after the reaction is completed, quench with a mixture of H2O and MeOH with a volume ratio of 1:1 under an ice bath, extract with dichloromethane and water, spin dry and separate by column chromatography to obtain the organic light-emitting compound; In the second preparation method, the molar ratio between the first raw material, the second raw material, the sodium tert-butoxide, the tris(tert-butyl)phosphine tetrafluoroborate and the palladium acetate is 1:2.4:3:0.1:0.1, and the molar ratio between the first solid product, the tert-butyllithium, the BBr3 and the DIPEA is 1:1.2:2:2; The third preparation method: Dissolve the first raw material, the second raw material and cesium carbonate in DMF, heat to 70 °C under nitrogen conditions for reaction overnight; after the reaction is completed and cooled to room temperature, pour it into ice water, filter by suction to obtain the precipitated solid, extract with dichloromethane and water, spin dry and separate by column chromatography to obtain the first solid product; Dissolve the first solid product, the third raw material and cesium carbonate in DMF, heat to 155 °C under nitrogen and stir for 8 hours; after the reaction is completed and cooled to room temperature, pour it into ice water, filter by suction to obtain the precipitated solid, and recrystallize with dichloromethane and methanol to obtain the second solid product; Place the second solid product in a container, dissolve it with ultra-dry tert-butylbenzene, displace nitrogen, and dropwise add tert-butyllithium at -30 °C, then react at 70 °C for 2 h; after cooling to -30 °C, dropwise add BBr3, and react for 1 h after returning to room temperature; after cooling to 0 °C, dropwise add DIPEA and reflux at 160 °C overnight; after the reaction is completed, quench with a mixture of H2O and MeOH with a volume ratio of 1:1 under an ice bath, extract with dichloromethane and water, and separate by column chromatography after rotary evaporation to obtain the organic light-emitting compound; In the third preparation method, the molar ratio between the first raw material, the second raw material and the cesium carbonate added for the first time is 2:1:1.5, the molar ratio between the first solid product, the third raw material and the cesium carbonate added for the second time is 1:1.2:1.5, and the molar ratio between the second solid product, tert-butyllithium, BBr3 and DIPEA is 1:1.2:2:2; The fourth preparation method: Dissolve the first raw material, the second raw material and sodium tert-butoxide in PhMe2, displace nitrogen and add tris(tert-butyl)phosphine tetrafluoroborate and palladium acetate, and heat to 150 °C to react overnight; after the reaction is completed and cooled to room temperature, extract the reaction system with dichloromethane and water, rotary evaporate the organic phase and separate by column chromatography to obtain the first solid product; Dissolve the first solid product, the third raw material and cesium carbonate in DMF, heat to 155 °C under nitrogen and stir for 8 hours; after the reaction is completed and cooled to room temperature, pour it into ice water, filter by suction to obtain the precipitated solid, and recrystallize with dichloromethane and methanol to obtain the second solid product; Place the second solid product in a container, dissolve it with ultra-dry tert-butylbenzene, displace nitrogen, and dropwise add tert-butyllithium at -30 °C, then react at 70 °C for 2 h; after cooling to -30 °C, dropwise add BBr3, and react for 1 h after returning to room temperature; after cooling to 0 °C, dropwise add DIPEA and reflux at 160 °C overnight; after the reaction is completed, quench with a mixture of H2O and MeOH with a volume ratio of 1:1 under an ice bath, extract with dichloromethane and water, and separate by column chromatography after rotary evaporation to obtain the organic light-emitting compound; In the fourth preparation method, the molar ratio between the first raw material, the second raw material, sodium tert-butoxide, tris(tert-butyl)phosphine tetrafluoroborate and palladium acetate is 1:1.2:1.5:0.1:0.1, the molar ratio between the first solid product, the third raw material and cesium carbonate is 1:1.2:1.5, and the molar ratio between the second solid product, tert-butyllithium, BBr3 and DIPEA is 1:1.2:2:2; The fifth preparation method: Dissolve the first raw material, the second raw material and sodium tert-butoxide in PhMe2. After purging with nitrogen, add tris(tert-butyl)phosphine tetrafluoroborate and palladium acetate, and heat to 120 °C for reaction for 3 h. After the reaction is completed and cooled to room temperature, extract the reaction system with dichloromethane and water. After the organic phase is dried by rotation, separate by column chromatography to obtain the first solid product. The molar ratio between the first raw material, the second raw material, the sodium tert-butoxide, the tris(tert-butyl)phosphine tetrafluoroborate and the palladium acetate is 2:1:1.2:0.05:0.05; Dissolve the first solid product, the third raw material and sodium tert-butoxide in PhMe2. After purging with nitrogen, add tris(tert-butyl)phosphine tetrafluoroborate and palladium acetate, and heat to 150 °C for reaction overnight. After the reaction is completed and cooled to room temperature, extract the reaction system with dichloromethane and water. After the organic phase is dried by rotation, separate by column chromatography to obtain the second solid product. The molar ratio between the first solid product, the third raw material, the sodium tert-butoxide, the tris(tert-butyl)phosphine tetrafluoroborate and the palladium acetate is 1:1.2:1.5:0.1:0.1; Place the second solid product in a container, dissolve it with ultra-dry tert-butylbenzene, purge with nitrogen, and add tert-butyllithium dropwise at -30 °C, then react at 70 °C for 2 h. After cooling to -30 °C, add BBr3 dropwise, and react at room temperature for 1 h. After cooling to 0 °C, add DIPEA dropwise and reflux at 160 °C overnight. After the reaction is completed, quench with a mixture of H2O and MeOH with a volume ratio of 1:1 under an ice-water bath, extract with dichloromethane and water, and after the organic phase is dried by rotation, separate by column chromatography to obtain the organic light-emitting compound. The molar ratio between the second solid product, the tert-butyllithium, the BBr3 and the DIPEA is 1:1.2:2:

2.

4. The preparation method of the organic light-emitting compound applicable to solution processing according to claim 3, characterized in that, The first raw material is any one of the following compounds A-1 to A-7:

5. The preparation method of the organic light-emitting compound applicable to solution processing according to claim 3, characterized in that, The selection ranges of the second raw material and the third raw material are the same, and each is any one of the following compounds B-1 to B-26:

6. An organic electroluminescent device, comprising an anode, a cathode, and an organic thin film layer disposed between the anode and the cathode, the organic thin film layer including a light-emitting layer, the light-emitting layer being prepared by a solution processing method, the light-emitting layer including a light-emitting material and a host material, characterized in that, The light-emitting material uses the solution-processable organic light-emitting compound according to any one of claims 1-2.

7. The organic electroluminescent device according to claim 6, characterized in that, The host material is mCPBC.

8. The organic electroluminescent device according to claim 6, wherein In the light-emitting layer, by mass percentage, the light-emitting material accounts for 0.5-30%, and the balance is the host material.

9. The organic electroluminescent device according to claim 6, characterized in that, The organic thin film layer further includes a first hole transport layer, a second hole transport layer, a first electron transport layer, a second electron transport layer and an electron injection layer; The anode, the first hole transport layer, the second hole transport layer, the light-emitting layer, the first electron transport layer, the second electron transport layer, the electron injection layer and the cathode are arranged in sequence from bottom to top.

10. The organic electroluminescent device according to claim 9, wherein The first hole transport layer is prepared from a mixed solution of PEDOT:PSS and PFI with a mass ratio of 1:5; The second hole transport layer is prepared from poly-HTL; The first electron transport layer is prepared from DMFBD-TRZ; The second electron transport layer is prepared from Na-An-BI; The electron injection layer is prepared from Liq.

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