An organic electroluminescent compound, a preparation method and application thereof, and an organic electroluminescent device containing the same

Abstract

The present invention belongs to the field of organic photoelectric materials, and discloses an organic electroluminescent compound, a preparation method and application thereof, and an organic electroluminescent device containing the same. The general structural formula of the organic electroluminescent compound is that the compound uses an alkyl group with smaller steric hindrance to replace the aryl group, so that the molecular structure has a smaller torsion angle, thereby obtaining a more three-dimensional spatial conformation, which is conducive to improving carrier mobility, obtaining a smaller driving voltage and higher efficiency.

Description

Technical Field

[0001] The invention belongs to the field of organic photoelectric materials, and specifically relates to an organic electroluminescent compound and a preparation method and application thereof, and an organic electroluminescent device containing the same. Background Art

[0002] OLED materials are divided into luminescent materials, hole transport materials, electron transport materials, etc. Among them, hole transport materials usually have a low highest occupied molecular orbital (HOMO) value, and the excitons generated in the luminescent layer diffuse to the hole transport layer interface or the hole transport layer side, which ultimately leads to luminescence at the interface of the luminescent layer or charge imbalance in the luminescent layer, thereby emitting light at the interface of the hole transport layer, reducing the color purity and efficiency of the organic electroluminescent device, and shortening its life. Introducing a luminescent auxiliary layer between the luminescent layer and the hole transport layer can effectively avoid the above technical problems.

[0003] However, currently, the materials used as light-emitting auxiliary layers are limited. Most of these materials use fluorene ring structures, which have high hole mobility and high T1 energy to block the diffusion of excitons after recombination 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. Summary of the invention

[0004] In view of this, the present invention provides a luminescent auxiliary material, which adopts an alkyl group with smaller steric hindrance instead of an aromatic group, so that the molecular structure has a smaller torsion angle, thereby obtaining a more three-dimensional spatial conformation, which is beneficial to improving the carrier mobility, obtaining a smaller driving voltage and a higher efficiency.

[0005] In order to achieve the above-mentioned object, the first object of the present invention is to provide an organic electroluminescent compound. The following technical scheme is adopted:

[0006] An organic electroluminescent compound has the following general structural formula:

[0007]

[0008] in,

[0009] X is independently selected from chemical bonds, O, S, Se, Si (R 2 R 3 ), C(R 4 R 5 ), NR 6 One of the above, and the R 2 ~R 6 Each independently represents a substituted or unsubstituted C 1 ~C 12Alkyl, substituted or unsubstituted C 6 ~C 18 Any one of an aryl group, a substituted or unsubstituted 3- to 30-membered heteroaryl group;

[0010] R1 is substituted or unsubstituted C 1 -C 30 Alkyl, substituted or unsubstituted C 1 -C 30 Alkoxy, substituted or unsubstituted C 1 -C 30 Alkylthio, substituted or unsubstituted C 3 -C 30 Any of the silane groups;

[0011] L1, L2 represent substituted or unsubstituted C 5 -C 30 aryl, substituted or unsubstituted 3- to 30-membered heteroaryl, substituted or unsubstituted C 10 -C 30 Condensed ring group, substituted or unsubstituted C 5- C 30 Spirocyclic group, or connected with adjacent substituents to form a monocyclic or polycyclic C 3 -C 30 Aliphatic ring or C 6- C 30 The carbon atoms in any of the aromatic rings may be replaced by one or more heteroatoms such as nitrogen, oxygen, sulfur, silicon, etc.;

[0012] Ar1 and Ar2 represent substituted or unsubstituted C 6 -C 30 aryl, substituted or unsubstituted 3- to 30-membered heteroaryl, substituted or unsubstituted C 10 -C 30 Condensed ring group, substituted or unsubstituted C 5- C 30 Spirocyclic group, or connected with adjacent substituents to form a monocyclic or polycyclic C 3 -C 30 Aliphatic ring or C 6- C 30 In any of the aromatic rings, the carbon atoms may be replaced by one or more heteroatoms such as nitrogen, oxygen, sulfur, and silicon.

[0013] It should be understood that the term "substituted or unsubstituted" of the present invention means substituted by one, two or more substituents selected from the following: deuterium; halogen group; nitrile group; hydroxyl group; carbonyl group; ester group; silyl group; boron group; substituted or unsubstituted alkyl group; substituted or unsubstituted cycloalkyl group; substituted or unsubstituted alkoxy group; substituted or unsubstituted alkenyl group; substituted or unsubstituted alkylamino group; substituted or unsubstituted heterocyclylamino group; substituted or unsubstituted arylamino group; substituted or unsubstituted aryl group; and substituted or unsubstituted heterocyclyl group, or substituted by two or more substituents connected to each other among the substituents shown above, or having no substituents. For example, "substituents connected to each other by two or more substituents" can include biphenyl. In other words, biphenyl can be aryl, or it can be interpreted as a substituent connected to two phenyl groups.

[0014] Furthermore, R1 is methyl, ethyl, propyl, isopropyl, butyl, tert-butyl, alkoxy, alkylthio or silyl; L1 and L2 are each independently one of phenyl, thienyl, furanyl, naphthyl or a derivative thereof; Ar1 ​​and Ar2 are each independently one of naphthyl, phenanthrenyl, phenyl, methylphenyl, dimethylphenyl, terphenyl, biphenyl, dibenzofuran, dibenzothiophene, cyclopentadithiophene, cyclopentadifuran, dimethylfluorene or a derivative thereof.

[0015] Furthermore, the general formula I is represented by any one of the following formulas (1)-(198):

[0016]

[0017]

[0018]

[0019]

[0020]

[0021]

[0022]

[0023]

[0024]

[0025] The second object of the present invention is to provide a method for preparing the organic electroluminescent compound as described above, using the following technical scheme:

[0026] A method for preparing an organic electroluminescent compound comprises the following steps:

[0027] (1) Add the reactants to a three-necked flask, add anhydrous tetrahydrofuran and replace with nitrogen three times, then cool the reaction system to -78°C, add n-butyl lithium dropwise, stir for 2 hours, dissolve reactant A in tetrahydrofuran, add dropwise to the reaction system, heat to room temperature after the addition is complete, stir for 10 hours, add distilled water to terminate the reaction, separate the organic phase, add anhydrous sodium sulfate, dry and spin dry to obtain intermediate C;

[0028] (2) Add intermediate C to a three-necked flask, cool to -10°C, add triethylsilane, stir for 30 min, add methanesulfonic acid, warm to room temperature and stir overnight, add water to terminate the reaction, separate the liquids, collect the organic phase, extract the aqueous phase three times with dichloromethane, combine the organic phases, add anhydrous sodium sulfate to dry and spin dry to obtain a white solid powder intermediate D;

[0029] (3) Add intermediate D to a three-necked flask, add tetrahydrofuran and stir until fully dissolved, add potassium tert-butoxide and stir for 2 h, slowly add iodomethane dropwise, reflux and stir overnight, cool to room temperature, add saturated ammonium chloride solution to quench the reaction, separate the liquids, collect the organic phase, extract the aqueous phase with dichloromethane three times, combine the organic phases, add anhydrous sodium sulfate to dry and spin dry to obtain a white solid powder F;

[0030] (4) Add intermediates F and G to a three-necked flask, add toluene and stir, replace with nitrogen three times, add sodium tert-butoxide, tri(dibenzylideneacetone)dipalladium, and tri-tert-butylphosphine in sequence, heat to 110°C and stir overnight. Cool to room temperature, add water to terminate the reaction, separate the liquids, collect the organic phase, extract the aqueous phase with dichloromethane three times, combine the organic phases, add anhydrous sodium sulfate to dry, and perform column chromatography to obtain the product of formula I; and,

[0031] The specific synthetic route is shown in Reaction Scheme 1:

[0032]

[0033] wherein X, R1, L1, L2, Ar1 and Ar2 have the meanings given in claim 1.

[0034] The third object of the present invention is to provide a use of the organic electroluminescent compound as described above in the preparation of an organic light-emitting device, an organic solar cell, an electronic paper, an organic photoreceptor or an organic thin film transistor.

[0035] A fourth object of the present invention is to provide an organic electroluminescent device, comprising a first electrode, a second electrode, and one or more organic layers disposed between the first electrode and the second electrode; and

[0036] The organic layer includes at least one of a hole injection layer, a hole transport layer, a light-emitting auxiliary layer, a light-emitting layer, an electron transport layer and an electron injection layer; and,

[0037] The light-emitting auxiliary layer contains one or more organic electroluminescent compounds as described above.

[0038] The present invention does not limit the preparation method of the organic electroluminescent device. It is preferred to use thin film evaporation, electron beam evaporation or physical vapor deposition methods to evaporate metals and conductive oxides and their alloys on a substrate to form an anode, and then form an organic layer and evaporate a cathode thereon to obtain an organic electroluminescent device.

[0039] Compared with the prior art, the present invention provides an organic electroluminescent compound using an alkyl group instead of an aryl group. This type of compound uses an alkyl group with small steric hindrance to replace the aryl group in the existing compound, so that the molecular structure has a smaller torsion angle, thereby obtaining a more three-dimensional spatial conformation, which is beneficial to improving the carrier mobility, obtaining a smaller driving voltage and a higher efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0040] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on the provided drawings without paying creative work.

[0041] Figure 1 Schematic diagram of the spatial structure of the compound (2) of the present invention and the compound of comparative example 1. DETAILED DESCRIPTION

[0042] The technical solutions in the embodiments of the present invention will be described clearly and completely 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. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0043] In this specification, each embodiment is described in a progressive manner, and each embodiment focuses on the differences from other embodiments. The same or similar parts between the embodiments can be referred to each other. For the device disclosed in the embodiment, since it corresponds to the method disclosed in the embodiment, the description is relatively simple, and the relevant parts can be referred to the method part.

[0044] Example 1: Synthesis of Compound 1

[0045]

[0046] (1) 333 mmol of intermediate B1 was added to a three-necked flask, THF was added and stirred until fully dissolved, nitrogen was replaced three times, the temperature was lowered to -78°C, 305 mmol of n-butyl lithium was slowly added dropwise, and stirred for 2 h. 277 mmol of A1 was dissolved in THF and slowly added to the reaction system. After the addition was completed, the temperature was raised to room temperature and stirred overnight. Dilute hydrochloric acid was slowly added to terminate the reaction, the liquids were separated, the organic phase was collected, the aqueous phase was extracted three times with dichloromethane, the organic phases were combined, anhydrous sodium sulfate was added to dry, and 90 g of white solid powder C1 was obtained after spin drying.

[0047] (2) Add 263 mmol of intermediate C1 into a three-necked flask, add dichloromethane and stir until fully dissolved, cool to -10°C, add 1.3 mol of triethylsilane, stir for 30 min, add 1.3 mol of methanesulfonic acid, warm to room temperature and stir overnight, add water to terminate the reaction, separate the liquids, collect the organic phase, extract the aqueous phase three times with dichloromethane, combine the organic phases, add anhydrous sodium sulfate to dry, and spin dry to obtain 80 g of white solid powder.

[0048] (3) Add 245 mmol of intermediate D1 into a three-necked flask, add tetrahydrofuran and stir until fully dissolved, add 490 mmol of potassium tert-butoxide and stir for 2 h, slowly add 1.2 mol of iodomethane dropwise, reflux and stir overnight, cool to room temperature, add saturated ammonium chloride solution to quench the reaction, separate the layers, collect the organic phase, extract the aqueous phase with dichloromethane three times, combine the organic phases, add anhydrous sodium sulfate to dry, and spin dry to obtain 80 g of white solid powder F1.

[0049] (4) Add 58mmol of intermediate F1 and 62mmol of G1 to a three-well, add toluene and stir, replace with nitrogen three times, add 117mmol of sodium tert-butoxide, 0.6mmol of tris(dibenzylideneacetone)dipalladium, and 3mmol of tri-tert-butylphosphine in sequence, heat to 110°C and stir overnight. Cool to room temperature, add water to terminate the reaction, separate the liquids, collect the organic phase, extract the aqueous phase with dichloromethane three times, combine the organic phases, add anhydrous sodium sulfate to dry, and perform column chromatography to obtain 35g of the product (yield: 90%).

[0050] Example 2: Synthesis of Compound 8

[0051]

[0052] (1) 333 mmol of intermediate B3 was added to a three-necked flask, THF was added and stirred until fully dissolved, nitrogen was replaced three times, the temperature was lowered to -78°C, 305 mmol of n-butyl lithium was slowly added dropwise, and stirred for 2 h. 277 mmol of A3 was dissolved in THF and slowly added to the reaction system. After the addition was completed, the temperature was raised to room temperature and stirred overnight. Dilute hydrochloric acid was slowly added to terminate the reaction, the liquids were separated, the organic phase was collected, the aqueous phase was extracted three times with dichloromethane, the organic phases were combined, anhydrous sodium sulfate was added to dry, and 90 g of white solid powder C3 was obtained after spin drying.

[0053] (2) Add 263 mmol of intermediate C3 into a three-necked flask, add dichloromethane and stir until fully dissolved, cool to -10°C, add 1.3 mol of triethylsilane, stir for 30 min, add 1.3 mol of methanesulfonic acid, warm to room temperature and stir overnight, add water to terminate the reaction, separate the liquids, collect the organic phase, extract the aqueous phase three times with dichloromethane, combine the organic phases, add anhydrous sodium sulfate to dry, and spin dry to obtain 80 g of white solid powder.

[0054] (3) 245 mmol of intermediate D3 was added to a three-necked flask, tetrahydrofuran was added and stirred until fully dissolved, 490 mmol of potassium tert-butoxide was added and stirred for 2 h, 1.2 mol of iodine 2-propane was slowly added dropwise, the mixture was refluxed and stirred overnight, cooled to room temperature, saturated ammonium chloride solution was added to quench the reaction, the liquids were separated, the organic phase was collected, the aqueous phase was extracted 3 times with dichloromethane, the organic phases were combined, anhydrous sodium sulfate was added to dry, and 85 g of white solid powder F3 was obtained after spin drying.

[0055] (4) Add 54 mmol of intermediate F3 and 57 mmol of G3 to a three-well, add toluene and stir, replace with nitrogen three times, add 108 mmol of sodium tert-butoxide, 0.6 mmol of tris(dibenzylideneacetone)dipalladium, and 3 mmol of tri-tert-butylphosphine in sequence, heat to 110°C and stir overnight. Cool to room temperature, add water to terminate the reaction, separate the liquids, collect the organic phase, extract the aqueous phase with dichloromethane three times, combine the organic phases, add anhydrous sodium sulfate to dry, and perform column chromatography to obtain 38 g (yield: 95%) of the product.

[0056] Example 3: Synthesis of Compound 7

[0057]

[0058] (1) 333 mmol of intermediate B4 was added to a three-necked flask, THF was added and stirred until fully dissolved, nitrogen was replaced three times, the temperature was lowered to -78°C, 305 mmol of n-butyl lithium was slowly added dropwise, and stirred for 2 h. 277 mmol of A4 was dissolved in THF and slowly added to the reaction system. After the addition was completed, the temperature was raised to room temperature and stirred overnight. Dilute hydrochloric acid was slowly added to terminate the reaction, the liquids were separated, the organic phase was collected, the aqueous phase was extracted three times with dichloromethane, the organic phases were combined, anhydrous sodium sulfate was added to dry, and 90 g of white solid powder C3 was obtained after spin drying.

[0059] (2) Add 263 mmol of the intermediate C4 into a three-necked flask, add dichloromethane and stir until fully dissolved, cool to -10°C, add 1.3 mol of triethylsilane, stir for 30 min, add 1.3 mol of methanesulfonic acid, warm to room temperature and stir overnight, add water to terminate the reaction, separate the layers, collect the organic phase, extract the aqueous phase three times with dichloromethane, combine the organic phases, add anhydrous sodium sulfate to dry, and spin dry to obtain 80 g of a white solid powder.

[0060] (3) Add 245 mmol of intermediate D4 into a three-necked flask, add tetrahydrofuran and stir until fully dissolved, add 490 mmol of potassium tert-butoxide and stir for 2 h, slowly add 1.2 mol of iodine 2-propane and reflux with stirring overnight, cool to room temperature, add saturated ammonium chloride solution to quench the reaction, separate the layers, collect the organic phase, extract the aqueous phase with dichloromethane three times, combine the organic phases, add anhydrous sodium sulfate to dry, and spin dry to obtain 390 g of white solid powder F.

[0061] (4) Add 52mmol of intermediate F4 and 53mmol of G4 to a three-well, add toluene and stir, replace with nitrogen three times, add 108mmol of sodium tert-butoxide, 0.5mmol of tris(dibenzylideneacetone)dipalladium, and 2mmol of tri-tert-butylphosphine in sequence, heat to 110°C and stir overnight. Cool to room temperature, add water to terminate the reaction, separate the liquids, collect the organic phase, extract the aqueous phase with dichloromethane three times, combine the organic phases, add anhydrous sodium sulfate to dry, and perform column chromatography to obtain 35g of the product (yield: 94.5%).

[0062] Example 4: Synthesis of Compound 32

[0063]

[0064] (1) 225 mmol of intermediate B5 was added to a three-necked flask, THF was added and stirred until fully dissolved, nitrogen was replaced three times, the temperature was lowered to -78°C, 247 mmol of n-butyl lithium was slowly added dropwise, and stirred for 2 h. 270 mmol of A5 was dissolved in THF and slowly added to the reaction system. After the addition was completed, the temperature was raised to room temperature and stirred overnight. Dilute hydrochloric acid was slowly added to terminate the reaction, the liquids were separated, the organic phase was collected, the aqueous phase was extracted three times with dichloromethane, the organic phases were combined, anhydrous sodium sulfate was added to dry, and 83 g of white solid powder C3 was obtained after spin drying.

[0065] (2) Add 215 mmol of intermediate C5 into a three-necked flask, add dichloromethane and stir until fully dissolved, cool to -10°C, add 1 mol of triethylsilane, stir for 30 min, add 1 mol of methanesulfonic acid, warm to room temperature and stir overnight, add water to terminate the reaction, separate the liquids, collect the organic phase, extract the aqueous phase three times with dichloromethane, combine the organic phases, add anhydrous sodium sulfate to dry, and spin dry to obtain 76 g of white solid powder.

[0066] (3) Add 206 mmol of intermediate D5 into a three-necked flask, add tetrahydrofuran and stir until fully dissolved, add 412 mmol of potassium tert-butoxide and stir for 2 h, slowly add 1 mol of tert-butane iodide dropwise, reflux and stir overnight, cool to room temperature, add saturated ammonium chloride solution to quench the reaction, separate the layers, collect the organic phase, extract the aqueous phase with dichloromethane three times, combine the organic phases, add anhydrous sodium sulfate to dry, and spin dry to obtain 385 g of white solid powder F.

[0067] (4) Add 47 mmol of intermediate F5 and 49 mmol of G5 to a three-well, add toluene and stir, replace with nitrogen three times, add 94 mmol of sodium tert-butoxide, 0.5 mmol of tris(dibenzylideneacetone)dipalladium, and 2.5 mmol of tri-tert-butylphosphine in sequence, heat to 110°C and stir overnight. Cool to room temperature, add water to terminate the reaction, separate the liquids, collect the organic phase, extract the aqueous phase with dichloromethane three times, combine the organic phases, add anhydrous sodium sulfate to dry, and perform column chromatography to obtain 32 g (yield: 94%) of the product.

[0068] Embodiment 5 to Embodiment 20

[0069] The synthesis of compounds 3, 10, 11, 14, 17, 20, 22, 28, 32, 35, 39, 40, 43, 46, 50 and 52 was completed by referring to the synthesis method of Examples 1 to 4. The molecular formulas and mass spectrometry characterization data are shown in Table 1 below.

[0070] Table 1 Structural characterization data and yields of products of Examples 5 to 20

[0071]

[0072]

[0073] In addition, it should be noted that other compounds of the present application can be obtained by referring to the synthesis methods of the embodiments listed above, so they will not be described in detail here.

[0074] Furthermore, the present invention also provides an organic electroluminescent device, comprising a first electrode, a second electrode opposite to the first electrode, and one or more organic layers between the first electrode and the second electrode, wherein at least one of the organic layers contains the compound represented by formula I prepared by the present invention.

[0075] The organic light-emitting element of the present invention may have a structure including a hole injection layer, a hole transport layer, an electron blocking layer, a light-emitting auxiliary layer, a light-emitting layer, a hole blocking layer, an electron transport layer, an electron injection layer, etc. as organic layers. However, the structure of the organic light-emitting element is not limited thereto, and may include fewer or more organic layers.

[0076] According to one embodiment of the present specification, the organic layer comprises a light-emitting auxiliary layer, and the light-emitting auxiliary layer comprises the compound represented by formula I prepared by the present invention.

[0077] When the organic light emitting element includes a plurality of organic layers, the organic layers may be formed of the same substance or different substances.

[0078] When manufacturing an organic light-emitting element, the compound represented by the chemical formula I may be vacuum deposited or solution coated to form an organic layer, wherein the solution coating method refers to spin coating, dip coating, blade coating, inkjet printing, screen printing, spraying, roller coating, etc., but is not limited thereto.

[0079] The organic light emitting element of the present invention may be a top emission type, a bottom emission type or a bi-directional emission type depending on the materials used.

[0080] The device of the present invention can be used in organic light-emitting devices, organic solar cells, electronic paper, organic photoreceptors or organic thin film transistors.

[0081] Example 21 Preparation of red organic electroluminescent device

[0082] a. ITO anode: Wash the ITO (indium tin oxide)-Ag-ITO (indium tin oxide) glass substrate with a coating thickness of 150nm in distilled water twice, ultrasonically wash for 30 minutes, and then repeatedly wash it with distilled water twice, ultrasonically wash for 10 minutes. After washing, transfer it to a spin dryer for drying, and finally bake it in a vacuum oven at 220℃ for 2 hours. After baking, cool it down and it can be used. Use this substrate as the anode and use a vapor deposition machine to perform the vapor deposition device process, and vapor deposit other functional layers on it in sequence;

[0083] 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; wherein the evaporation rate ratio of HT and P-dopant is 97:3, and the thickness is 10 nm;

[0084] c. HTL (hole transport layer): At a deposition rate of 100%, 120 nm of HT was vacuum-deposited on the hole injection layer as a hole transport layer.

[0085] d. Light-emitting auxiliary layer: At a deposition rate of , vacuum-deposit 95 nm of the compound 1 provided in Example 1 on the hole transport layer as a light-emitting auxiliary layer;

[0086] e. EML (light-emitting layer): Then on the above-mentioned light-emitting auxiliary layer, The evaporation rate of the host material (Host) and the dopant material (Dopant) are vacuum evaporated as the light-emitting layer (40nm). The chemical formulas of the Host and Dopant are as follows; wherein the evaporation rate ratio of the Host and Dopant is 97:3;

[0087] f. HB (hole blocking layer): The evaporation rate is 5.0 nm, and the hole blocking layer is vacuum-deposited with a thickness of 5.0 nm;

[0088] g. ETL (Electron Transport Layer): At a deposition rate of , ET and Liq with a thickness of 30 nm were vacuum-deposited as an electron transport layer, and the chemical formula of ET is shown below; wherein the deposition rate ratio of ET to Liq is 50:50;

[0089] 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;

[0090] i. Cathode: 18 nm of magnesium and silver were evaporated at a deposition rate ratio of 1:9 to obtain an OLED device;

[0091] 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;

[0092] 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.

[0093] Device structure: ITO / Ag / ITO / HT:P-dopant(10nm,97:3) / HT(120nm) / Compound 1(95nm) / Host:Dopant(40nm,97:3) / HB(5nm) / ET:Liq(30nm,5:5) / Yb(1nm) / Mg:Ag(18nm,1:9) / CPL(70nm).

[0094] The structure of the compound used in the preparation process of the organic electroluminescent device is shown below:

[0095]

[0096] Example 22 to Example 40

[0097] The organic electroluminescent devices of Examples 22 to 40 were prepared according to the above-mentioned method for preparing an organic electroluminescent device, except that the compound 1 in Example 21 was replaced by the corresponding compounds in Table 1 to form a light-emitting auxiliary layer.

[0098] In order to further demonstrate the beneficial effects of the present invention and to better understand the present invention, the properties and application performances of the organic electroluminescent compounds and devices containing the same according to the present invention are further illustrated by the following comparative examples, but they should not be construed as limitations on the present invention. The product properties obtained by other measurement experiments conducted by technicians in this field based on the above invention content and the applications based on the above properties are also considered to fall within the protection scope of the present invention.

[0099] Comparative Example 1

[0100] An organic electroluminescent device was prepared according to the above method for preparing an organic electroluminescent device, except that the compound 1 in Example 21 was replaced by a comparative compound 1, wherein the structure of the comparative compound 1 is as follows:

[0101]

[0102] Comparative Example 2

[0103] An organic electroluminescent device was prepared according to the above method for preparing an organic electroluminescent device, except that the compound 1 in Example 21 was replaced by a comparative compound 2, wherein the structure of the comparative compound 2 is as follows:

[0104]

[0105] Comparative Example 3

[0106] An organic electroluminescent device was prepared according to the above method for preparing an organic electroluminescent device, except that the compound 1 in Example 21 was replaced by a comparative compound 3, wherein the structure of the comparative compound 3 is as follows:

[0107]

[0108] The driving voltage, glass transition temperature, luminous efficiency and life of the organic electroluminescent devices containing luminescent auxiliary materials obtained in Examples 21 to 40 and Comparative Examples 1 to 3 were characterized at a brightness of 1000 (nits). The test results are shown in Table 2.

[0109] Table 2 Luminescence characteristics of organic electroluminescent devices (brightness value is 1000 nits)

[0110]

[0111]

[0112] It can be seen from Table 2 that, compared with the existing organic electroluminescent device provided in Comparative Example 1, the driving voltage, luminous efficiency and life of the organic electroluminescent device embodiments 21 to 40 prepared using the luminescent auxiliary material provided by the present invention are improved.

[0113] The above description of the disclosed embodiments enables one skilled in the art to implement or use the present invention. Various modifications to these embodiments will be apparent to one skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention will not be limited to the embodiments shown herein, but rather to the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. An organic electroluminescent compound, It is characterized in that It has the following general structural formula: The general formula I is represented by any one of the following formulas (1)-(198):

2. A method for preparing the organic electroluminescent compound as claimed in claim 1, It is characterized in that The process comprises the following reaction steps: (1) Add the reactants to a three-necked flask, add anhydrous tetrahydrofuran and replace with nitrogen three times, then cool the reaction system to -78°C, add n-butyl lithium dropwise, stir for 2 hours, dissolve reactant A in tetrahydrofuran, add dropwise to the reaction system, heat to room temperature after the addition is complete, stir for 10 hours, add distilled water to terminate the reaction, separate the organic phase, add anhydrous sodium sulfate, dry and spin dry to obtain intermediate C; (2) Add intermediate C to a three-necked flask, cool to -10°C, add triethylsilane, stir for 30 min, add methanesulfonic acid, warm to room temperature and stir overnight, add water to terminate the reaction, separate the liquids, collect the organic phase, extract the aqueous phase three times with dichloromethane, combine the organic phases, add anhydrous sodium sulfate to dry and spin dry to obtain a white solid powder intermediate D; (3) Add intermediate D to a three-necked flask, add tetrahydrofuran and stir until fully dissolved, add potassium tert-butoxide and stir for 2 h, slowly add iodomethane dropwise, reflux and stir overnight, cool to room temperature, add saturated ammonium chloride solution to quench the reaction, separate the liquids, collect the organic phase, extract the aqueous phase with dichloromethane three times, combine the organic phases, add anhydrous sodium sulfate to dry and spin dry to obtain a white solid powder F; (4) Add intermediates F and G to a three-necked flask, add toluene and stir, replace with nitrogen three times, add sodium tert-butoxide, tri(dibenzylideneacetone)dipalladium, and tri-tert-butylphosphine in sequence, heat to 110° C. and stir overnight, cool to room temperature, add water to terminate the reaction, separate the liquids, collect the organic phase, extract the aqueous phase with dichloromethane three times, combine the organic phases, add anhydrous sodium sulfate to dry, and perform column chromatography to obtain the product structure shown in Formula I; and, The specific synthetic route is shown in Reaction Scheme 1:

3. Use of the organic electroluminescent compound as claimed in claim 1, It is characterized in that Application of the organic electroluminescent compound in preparing an organic light-emitting device.

4. An organic electroluminescent device, It is characterized in that comprising a first electrode, a second electrode, and one or more organic layers disposed between the first electrode and the second electrode; and, The organic layer includes at least one of a hole injection layer, a hole transport layer, a light-emitting auxiliary layer, a light-emitting layer, an electron transport layer and an electron injection layer; and, The light-emitting auxiliary layer comprises one or more organic electroluminescent compounds as claimed in claim 1 .

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