A compound for organic light-emitting material

Abstract

The present invention belongs to the technical field of organic light-emitting materials, and relates to a compound for organic light-emitting materials. In the compound provided by the present invention, a xanthene five-membered heterocycle is a parent core, and different groups are connected at specific positions for modification. The obtained compound has a suitable orbital energy level and a high triplet energy, and can be used as a light-emitting layer main body and a second hole transport material in an organic electroluminescent device, which can significantly improve the luminous efficiency and life of the device.

Description

Technical Field

[0001] The invention belongs to the technical field of organic luminescent materials and relates to a compound used for organic luminescent materials. Background Art

[0002] Organic light-emitting diodes (OLEDs) have the advantages of soft light emission, fast response speed, rich colors, and wide viewing angles. The working principle of OLED is that holes and electrons injected through the electrode enter the light-emitting material through the transport layer, and under the action of Coulomb force, holes and electrons combine to produce excitons, which radiate back to the ground state to emit photons.

[0003] However, since the interaction between the conjugated molecules that make up the organic light-emitting material is the van der Waals force, which is weak, the exciton binding energy is large, and the luminescence process is mainly the exciton behavior. According to the spin state, excitons are divided into triplet excitons (75%) and singlet excitons (25%). Triplet excitons are transition-forbidden and it is difficult for them to radiate and transition to emit photons, which limits the efficiency of OLED devices.

[0004] To solve this problem, researchers proposed phosphorescent OLED materials, which use heavy metal atoms to enhance spin-orbit coupling, break the triplet spin prohibition, and achieve room temperature luminescence of phosphorescence, breaking the previous theoretical limit of 25% internal quantum efficiency (IQE) of fluorescent OLEDs. In order to maximize the performance of phosphorescent materials, it is necessary to dope phosphorescent materials into host materials to reduce the quenching effect of the luminescent material itself, thereby obtaining higher device performance. The triplet energy of phosphorescent materials themselves is relatively high. As the main body of phosphorescent materials, their energy must be greater than that of luminescent materials, otherwise energy backflow is likely to occur, thereby reducing luminescence efficiency. In recent years, phosphorescent host materials have developed rapidly, but high triplet and high stability host materials have always been a hot topic in the industry.

[0005] In addition, OLED still faces many challenges. The conductivity of organic molecules is determined by two aspects: first, the intramolecular carrier transport originates from the conjugated π bond, and the pp electron cloud overlaps to form a bonding orbital (HOMO energy level) and an anti-bonding orbital (LUMO energy level). The bonding orbital has better delocalization, so this is conducive to the transmission of holes at the HOMO energy level; second, the transmission between molecules is mainly through a jumping model, which depends on the overlap of the electron cloud of the molecular orbital of the adjacent molecular frontier. Because the bonding orbital has good delocalization, the electron cloud overlaps better, which is also conducive to the hole transport of organic materials. It is difficult for organic materials to obtain high mobility, and the development of high-performance hole transport materials has always been the research goal of many researchers in the field.

[0006] Therefore, in the field of organic electroluminescent material technology, it is very important to construct a new compound that can not only enhance the stability of organic electroluminescent materials but also improve the photoelectric properties of organic electroluminescent devices. Summary of the invention

[0007] In view of this, the object of the present invention is to provide a compound for an organic light-emitting material. The present invention uses a xanthene five-membered heterocycle as a parent core, introduces different groups at specific positions, and effectively improves the carrier migration ability by connecting electron-donating groups or electron-withdrawing groups. The constructed novel organic compound has a suitable orbital energy level and triplet energy. As a second hole transport material or a phosphorescent host material, it can effectively improve the brightness efficiency and lifespan, and significantly improve the photoelectric performance of organic electroluminescent devices.

[0008] The structure of the xanthene five-membered heterocyclic ring involved in the present invention is as follows:

[0009] .

[0010] In a first aspect, the present invention provides a compound having a structure as shown in Formula 1,

[0011] ;

[0012] Wherein, T is selected from one of C and Si;

[0013] Y is selected from O, S, C(R 3 ) 2 、NAr 3 One of;

[0014] m and n are independently selected from any value of 0, 1, 2, 3, and 4;

[0015] Ar 1 and Ar 2 Each of the following is independently selected from a substituted or unsubstituted aryl group having C6 to C30, a substituted or unsubstituted heteroaryl group having N or O heteroatoms and having C3 to C30 carbon atoms, and an arylamine group containing an aryl group or a heteroaryl group;

[0016] R 1 , R 2 Each of R is independently selected from a methyl group and a phenyl group; 1 , R 2 When they are benzene rings at the same time, they can be connected to form a fluorene ring.

[0017] Furthermore, in the compound provided by the present invention, the R 3 One selected from methyl and phenyl;

[0018] The NAr 3 Ar3 One selected from benzene, biphenyl and terphenyl;

[0019] When m>1, a plurality of said Ar 1 The same or different from each other; when n>1, the plurality of Ar 2 the same as or different from one another;

[0020] Ar 1 ,Ar 2 、NAr 3 Any hydrogen atom in the molecule can be replaced by deuterium.

[0021] Furthermore, in the compounds provided by the present invention, the compounds have structures as shown in Formula 2 to Formula 7,

[0022]

[0023] Furthermore, in the compounds provided by the present invention, the heteroaryl group is selected from any one of the following structures:

[0024]

[0025]

[0026]

[0027]

[0028]

[0029] .

[0030] Furthermore, in the compound provided by the present invention, the aromatic amine group is selected from any one of the following structures,

[0031]

[0032]

[0033]

[0034]

[0035] .

[0036] Furthermore, the compound provided by the present invention has the structure shown below:

[0037]

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[0039]

[0040]

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[0070]

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[0098]

[0099] .

[0100] Furthermore, in the compounds provided by the present invention, the intermediates for synthesizing the compounds are selected from any one of the following structures:

[0101]

[0102]

[0103]

[0104]

[0105]

[0106] .

[0107] In a second aspect, the present invention provides use of the compound in an organic electroluminescent device or an organic electroluminescent apparatus.

[0108] In a third aspect, the present invention provides the use of the compound in the preparation of hole transport materials or phosphorescent host materials.

[0109] In a fourth aspect, the present invention provides an organic electroluminescent device, comprising an anode layer, a cathode layer, and an organic thin film layer located between the anode layer and the cathode layer, wherein the organic thin film layer comprises a hole injection layer, a first hole transport layer, a second hole transport layer, a light-emitting layer, a hole blocking layer, an electron transport layer and an electron injection layer, and the light-emitting layer contains the compound described in the present invention.

[0110] Compared with the prior art, the technical solution provided by the present invention has at least the following beneficial effects or advantages:

[0111] The present invention provides a compound, wherein a xanthene five-membered heterocyclic ring enhances the rigidity of a parent nucleus, connects different groups at specific positions, and is modified by electron-pulling or electron-donating groups to construct a compound with a specific structure having a suitable HOMO / LUMO energy level and a relatively high triplet energy. When used as a phosphorescent light-emitting main material, the energy transfer between the host and the guest is ensured, and when used as a second hole transport material, the carrier migration ability is enhanced, and both significantly improve the brightness efficiency and life of the device. The compound is a novel organic OLED functional material with relatively promising development prospects. BRIEF DESCRIPTION OF THE DRAWINGS

[0112] 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 some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0113] Figure 1 Schematic diagram of the structure of an organic electroluminescent element, wherein 1 is a substrate, 2 is an anode layer, 3 is a hole injection layer, 4 is a first hole transport layer, 5 is a second hole transport layer, 6 is a light-emitting layer, 7 is a hole blocking layer, 8 is an electron transport layer, 9 is an electron injection layer, and 10 is a cathode layer. DETAILED DESCRIPTION

[0114] The technical scheme of the present invention is described below in conjunction with the examples, but the present invention is not limited to the following examples. The experimental methods and detection methods described in each example are conventional methods unless otherwise specified; the reagents and materials are available on the market unless otherwise specified, and the % in the following examples are all mass percentages unless otherwise specified.

[0115] The structure of the xanthene five-membered heterocyclic ring involved in the present invention is as follows:

[0116] .

[0117] Preparation Example

[0118] This preparation example provides the synthesis methods of some intermediates and compounds. The synthesis methods of the remaining intermediates and compounds are similar methods and can be easily synthesized. The specific synthesis routes are shown below.

[0119] Synthesis of intermediate 1-a:

[0120]

[0121]

[0122] Synthesis of intermediate 1-1: Under nitrogen protection, raw material 1 (224 g, 1 mol), raw material 2 (180 g, 1 mol), Pd(PPh 3 ) 4 (tetrakis(triphenylphosphine)palladium, 23 g, 20 mmol), K 2 CO 3 (potassium carbonate, 276 g, 2 mol), TBAB (tetrabutylammonium bromide, 32.2 g, 0.1 mol), toluene (2000 mL), ethanol (1000 mL), water (500 mL), heated to 76 ° C and stirred for 8 h, then cooled to room temperature, washed with water until neutral, the organic phase was dried over anhydrous magnesium sulfate, passed through a silica gel column, and then purified by recrystallization from toluene to obtain 210 g of intermediate 1-1, with a yield of 75%.

[0123] Synthesis of intermediate 1-2: Under nitrogen protection, add intermediate 1-1 (140 g, 0.5 mol) and tetrahydrofuran (400 mL) to a three-necked flask, slowly add 1.0 M tetrahydrofuran solution of methylmagnesium bromide (1.0 M-THF, 800 mL) under stirring at room temperature 24°C, and heat to 50°C to continue the reaction for 5 h. After the reaction solution is cooled to room temperature, add aqueous ammonium chloride solution to quench the reaction, adjust pH to 3 with dilute hydrochloric acid, add 800 mL of dichloroethane to extract, stir evenly, wash repeatedly with water, dry the organic phase with anhydrous magnesium sulfate, filter and concentrate, squeeze out the solid with ethanol, and purify to obtain 114.8 g of intermediate 1-2 with a yield of 82%.

[0124] Synthesis of intermediate 1-3: Under nitrogen protection, add intermediate 1-2 (70.0 g, 0.25 mol), methanesulfonic acid (48 g, 0.5 mol), and toluene (500 mL) to a three-necked flask, and heat to 108 °C for 3 h. After cooling the reaction solution to room temperature, wash with water until neutral, dry the organic phase with anhydrous magnesium sulfate, filter and concentrate, and recrystallize and purify with a toluene / ethanol mixed solvent to obtain 52.4 g of intermediate 1-3 with a yield of 80%.

[0125] Synthesis of intermediate 1-4: Under nitrogen protection, intermediate 1-3 (52.4 g, 0.2 mol), methyl 5-chloro-2-hydroxybenzoate (37.2 g, 0.2 mol), cesium carbonate (130.3 g, 0.4 mol) and DMF solvent (300 mL) were added to the reaction bottle in sequence, and heated to reflux for reaction for 6 h. The system was cooled to room temperature, the reaction solution was filtered, and the filtrate was added to 900 mL of water while stirring. A white precipitate was generated, which was filtered. The filter cake was washed with water and ethanol in sequence to obtain a crude product, which was then purified by recrystallization using a toluene / ethanol mixed solvent to obtain 62.5 g of intermediate 1-4 with a yield of 73%.

[0126] The synthesis of intermediate 1-5 refers to the synthesis of intermediate 1-2, except that intermediate 1-1 is replaced by intermediate 1-4.

[0127] The synthesis of intermediate 1-a refers to the synthesis of intermediate 1-3, except that intermediate 1-2 is replaced by intermediate 1-5.

[0128] Synthesis of intermediate 1-b:

[0129]

[0130]

[0131] The synthesis of intermediate 1-6 refers to the synthesis of intermediate 1-1, except that raw material 1 is replaced by raw material 3.

[0132] The synthesis of intermediate 1-7 refers to the synthesis of intermediate 1-2, except that intermediate 1-1 is replaced by intermediate 1-6.

[0133] The synthesis of Intermediate 1-8 was prepared by referring to the synthesis of Intermediate 1-3, except that Intermediate 1-2 was replaced by Intermediate 1-7.

[0134] The synthesis of intermediate 1-9 refers to the synthesis of intermediate 1-4, except that intermediate 1-3 and methyl 5-chloro-2-hydroxybenzoate are replaced by intermediate 1-8 and 2,6-dibromophenol.

[0135] Synthesis of intermediate 1-b: Under nitrogen protection, add intermediate 1-9 (114 g, 0.2 mol) and tetrahydrofuran (300 mL) to a three-necked flask, stir and dissolve, then cool to -10 °C, slowly drop butyl lithium (250 mL, 0.4 mol, 1.6 M), keep warm for 1 hour, then start dropping diphenyldichlorosilane tetrahydrofuran solution (50.4 g, 0.2 mol, 200 mL tetrahydrofuran), keep warm for 1 hour, then naturally warm to room temperature and continue to react for 2 hours. After the reaction is completed, quench the reaction with an aqueous solution of ammonium chloride, add 500 mL of dichloroethane for extraction, repeatedly wash with water until neutral, dry and filter the organic phase with anhydrous magnesium sulfate, squeeze out with ethanol after concentration, and recrystallize and purify with a toluene / n-heptane mixed solvent to obtain 84.3 g of intermediate 1-b with a yield of 71%.

[0136] Synthesis of intermediate 1-c:

[0137]

[0138] The synthesis of intermediate 1-10 refers to the synthesis of intermediate 1-2, except that intermediate 1-1 and methylmagnesium bromide are replaced by intermediate 1-4 and phenylmagnesium bromide.

[0139] The synthesis of intermediate 1-c refers to the synthesis of intermediate 1-3, except that intermediate 1-2 is replaced by intermediate 1-10.

[0140] Synthesis of intermediate 1-d:

[0141]

[0142]

[0143] The synthesis of intermediate 1-11 refers to the synthesis of intermediate 1-1, except that raw material 2 is replaced by methyl 5-chlorobenzoate-2-boronic acid pinacol ester.

[0144] The synthesis of intermediate 1-12 refers to the synthesis of intermediate 1-2, except that intermediate 1-1 is replaced by intermediate 1-11.

[0145] The synthesis of intermediate 1-13 refers to the synthesis of intermediate 1-3, except that intermediate 1-2 is replaced by intermediate 1-12.

[0146] The synthesis of intermediate 1-14 refers to the synthesis of intermediate 1-4, except that intermediate 1-3 and 5-chloro-2-hydroxybenzoic acid methyl ester are replaced by intermediate 1-13 and 2-hydroxybenzoic acid methyl ester.

[0147] The synthesis of intermediate 1-15 refers to the synthesis of intermediate 1-2, except that intermediate 1-1 is replaced by intermediate 1-14.

[0148] The synthesis of intermediate 1-d refers to the synthesis of intermediate 1-3, except that intermediate 1-2 is replaced by intermediate 1-15.

[0149] Synthesis of intermediate 2-a:

[0150]

[0151]

[0152] The synthesis of intermediate 2-1 refers to the synthesis of intermediate 1-1, except that raw material 1 and raw material 2 are replaced by raw material 4 and 2-fluorophenylboronic acid.

[0153] Synthesis of intermediate 2-2: Under nitrogen protection, add intermediate 2-1 (135 g, 0.5 mol) and dichloromethane (1500 mL) to a dry three-necked flask, cool the reaction system to -5~0°C using an ice-salt bath, add boron tribromide (495 g, 2 mol), stir at room temperature for 6 h, and then pour into ice water to quench the reaction. The organic phase was washed with water until neutral, dried over anhydrous magnesium sulfate, filtered and concentrated, and purified by silica gel column to obtain 107.5 g of intermediate 2-2 with a yield of 84%.

[0154] The synthesis of intermediate 2-3 refers to the synthesis of intermediate 1-4, except that intermediate 1-3 and methyl 5-chloro-2-hydroxybenzoate are replaced by intermediate 2-2.

[0155] The synthesis of intermediate 2-4 refers to the synthesis of intermediate 1-4, except that intermediate 1-3 is replaced by intermediate 2-3.

[0156] The synthesis of intermediate 2-5 refers to the synthesis of intermediate 1-2, except that intermediate 1-1 is replaced by intermediate 2-4.

[0157] The synthesis of intermediate 2-a refers to the synthesis of intermediate 1-3, except that intermediate 1-2 is replaced by intermediate 2-5.

[0158] Synthesis of intermediate 2-b:

[0159]

[0160] The synthesis of intermediate 2-6 refers to the synthesis of intermediate 1-10, except that intermediate 1-4 is replaced by intermediate 2-4.

[0161] The synthesis of intermediate 2-b refers to the synthesis of intermediate 1-c, except that intermediate 1-10 is replaced by intermediate 2-6.

[0162] Synthesis of intermediate 2-c:

[0163]

[0164]

[0165] The synthesis of intermediate 2-7 refers to the synthesis of intermediate 1-1, except that raw material 1 and raw material 2 are replaced by raw material 4 and 4-chloro-2-fluorophenylboronic acid.

[0166] The synthesis of intermediate 2-8 refers to the synthesis of intermediate 2-2, except that intermediate 2-1 is replaced by intermediate 2-7.

[0167] The synthesis of intermediate 2-9 refers to the synthesis of intermediate 1-4, except that intermediate 1-3 and methyl 5-chloro-2-hydroxybenzoate are replaced by intermediate 2-8.

[0168] The synthesis of Intermediate 2-10 refers to the synthesis of Intermediate 1-14, except that Intermediate 1-13 is replaced by Intermediate 2-9.

[0169] The synthesis of intermediate 2-11 refers to the synthesis of intermediate 1-2, except that intermediate 1-1 is replaced by intermediate 2-10.

[0170] The synthesis of intermediate 2-c refers to the synthesis of intermediate 1-3, except that intermediate 1-2 is replaced by intermediate 2-11.

[0171] Synthesis of intermediate 3-a:

[0172]

[0173]

[0174] The synthesis of intermediate 3-1 refers to the synthesis of intermediate 1-1, except that raw material 2 is replaced by 2-nitrobenzeneboronic acid.

[0175] Synthesis of intermediate 3-2: Under nitrogen protection, add intermediate 3-1 (80 g, 0.3 mol), PPh3 (triphenylphosphine, 157.2 g, 0.6 mol), o-dichlorobenzene (300 mL) to a three-necked flask, stir and heat to 160 ° C for 18 h. After the reaction solution is cooled to room temperature, n-heptane is added to precipitate the solid product, which is filtered and purified by recrystallization with toluene to obtain 53.6 g of intermediate 3-2, with a yield of 76%.

[0176] Synthesis of intermediate 3-3: Under nitrogen protection, add intermediate 3-2 (47 g, 0.2 mol), iodobenzene (40.8 g, 0.2 mol), Pd 2 (dba) 3 (Tris(dibenzylideneacetone)dipalladium, 1.8 g, 2 mmol), P(t-Bu) 3(tri-tert-butylphosphine, 0.8 g, 4 mmol), sodium tert-butoxide (38.4 g, 0.4 mol), toluene (400 mL), stirred and heated to 110 ° C for reflux reaction for 2 h. After the reaction is complete, cool to room temperature, wash with water until neutral, dry the organic phase with anhydrous magnesium sulfate and filter, pass the filtrate through a silica gel column, concentrate the column liquid and recrystallize and purify it with a toluene / ethanol mixed solvent to obtain 52.8 g of intermediate 3-3, with a yield of 85%.

[0177] The synthesis of intermediate 3-4 refers to the synthesis of intermediate 1-4, except that intermediate 1-3 is replaced by intermediate 3-3.

[0178] The synthesis of intermediate 3-5 refers to the synthesis of intermediate 1-2, except that intermediate 1-1 is replaced by intermediate 3-4.

[0179] The synthesis of intermediate 3-a refers to the synthesis of intermediate 1-3, except that intermediate 1-2 is replaced by intermediate 3-5.

[0180] Synthesis of intermediate 3-b:

[0181]

[0182]

[0183] The synthesis of intermediate 3-6 refers to the synthesis of intermediate 1-14, except that intermediate 1-13 is replaced by starting material 1.

[0184] The synthesis of intermediate 3-7 refers to the synthesis of intermediate 1-2, except that intermediate 1-1 is replaced by intermediate 3-6.

[0185] The synthesis of intermediate 3-8 refers to the synthesis of intermediate 1-3, except that intermediate 1-2 is replaced by intermediate 3-7.

[0186] The synthesis of intermediate 3-9 refers to the synthesis of intermediate 1-1, except that raw material 1 and raw material 2 are replaced by intermediate 3-8 and 2-nitrobenzeneboronic acid.

[0187] The synthesis of intermediate 3-b refers to the synthesis of intermediate 3-2, except that intermediate 3-1 is replaced by intermediate 3-9.

[0188] Synthesis of intermediate 3-c:

[0189]

[0190]

[0191] The synthesis of intermediate 3-10 refers to the synthesis of intermediate 1-4, except that intermediate 1-3 is replaced by starting material 1.

[0192] The synthesis of intermediate 3-11 refers to the synthesis of intermediate 1-2, except that intermediate 1-1 is replaced by intermediate 3-10.

[0193] The synthesis of intermediate 3-12 refers to the synthesis of intermediate 1-3, except that intermediate 1-2 is replaced by intermediate 3-11.

[0194] The synthesis of intermediate 3-13 refers to the synthesis of intermediate 1-1, except that raw material 1 and raw material 2 are replaced by intermediate 3-12 and 2-nitrobenzeneboronic acid.

[0195] The synthesis of intermediate 3-14 needs to determine the reaction method according to the characteristics of the Ar1 group, and the conventional Suzuki or Ullmann synthesis method can be used to obtain intermediate 3-14.

[0196] The synthesis of intermediate 3-c refers to the synthesis of intermediate 3-2, except that intermediate 3-1 is replaced by intermediate 3-14.

[0197] Synthesis of intermediate 4-a:

[0198]

[0199]

[0200] Synthesis of intermediate 4-1: Under nitrogen protection, raw material 5 (161 g, 1 mol), NBS (N-bromosuccinimide, 178 g, 1 mol), and chloroform (600 mL) were added to a three-necked flask and stirred for reaction at room temperature for 3 h. The reaction solution was concentrated and purified by recrystallization with ethanol to obtain 205.5 g of intermediate 4-1 with a yield of 86%.

[0201] The synthesis of intermediate 4-2 refers to the synthesis of intermediate 1-1, except that raw material 1 and raw material 2 are replaced by intermediate 4-1 and 2-methylthiophenylboronic acid.

[0202] Synthesis of intermediate 4-3: Under nitrogen protection, add intermediate 4-2 (141.5 g, 0.5 mol), acetic anhydride (51 g, 0.5 mol), and pyridine (600 mL) into a three-necked flask, stir and heat to 100 °C for 2 h, detect the raw materials by TLC, cool to room temperature after the reaction is complete, concentrate and purify with ethanol recrystallization to obtain 130.1 g of intermediate 4-3, with a yield of 80%.

[0203] Synthesis of intermediate 4-4: Under nitrogen protection, add intermediate 4-3 (65 g, 0.2 mol), HBr (200 mL), and acetic acid (200 mL) into a three-necked flask, stir and heat to 100 °C for reaction, detect the raw materials by TLC, cool to room temperature after the reaction is complete, add toluene (300 mL), stir well and wash repeatedly with water until neutral, dry the organic phase with anhydrous magnesium sulfate, and purify it on a silica gel column to obtain 38.8 g of intermediate 4-4 with a yield of 77%.

[0204] The synthesis of intermediate 4-5 refers to the synthesis of intermediate 1-4, except that intermediate 1-3 is replaced by intermediate 4-4.

[0205] The synthesis of intermediate 4-6 refers to the synthesis of intermediate 1-2, except that intermediate 1-1 is replaced by intermediate 4-5.

[0206] The synthesis of intermediate 4-a refers to the synthesis of intermediate 1-3, except that intermediate 1-2 is replaced by intermediate 4-6.

[0207] Synthesis of intermediate 4-b:

[0208]

[0209]

[0210] The synthesis of intermediate 4-7 refers to the synthesis of intermediate 4-2, except that 2-methylthiophenylboronic acid is replaced by 4-chloro-2-methylthiophenylboronic acid.

[0211] The synthesis of intermediate 4-8 refers to the synthesis of intermediate 4-3, except that intermediate 4-2 is replaced by intermediate 4-7.

[0212] The synthesis of intermediate 4-9 refers to the synthesis of intermediate 4-4, except that intermediate 4-3 is replaced by intermediate 4-8.

[0213] The synthesis of intermediate 4-10 refers to the synthesis of intermediate 1-14, except that intermediate 1-13 is replaced by intermediate 4-9.

[0214] The synthesis of intermediate 4-11 refers to the synthesis of intermediate 1-2, except that intermediate 1-1 is replaced by intermediate 4-10.

[0215] The synthesis of intermediate 4-b refers to the synthesis of intermediate 1-3, except that intermediate 1-2 is replaced by intermediate 4-11.

[0216] Synthesis of compound 1-1:

[0217]

[0218] Under nitrogen protection, intermediate 1-a (8.2 g, 0.02 mol), diphenylamine (3.4 g, 0.02 mol), Pd 2 (dba) 3 (tris(dibenzylideneacetone)dipalladium, 0.18 g, 0.2 mmol), P(t-Bu) 3 (Tri-tert-butylphosphine, 0.08 g, 0.4 mmol), sodium tert-butoxide (7.7 g, 0.08 mol), toluene (100 mL), stirred and heated to 110 ° C for reflux reaction for 1.5 h. After the reaction is complete, cool to room temperature, wash with water until neutral, dry the organic phase with anhydrous magnesium sulfate, filter, pass the filtrate through a silica gel column, concentrate the column liquid and recrystallize and purify it with toluene to obtain 9.0 g of compound 1-1, with a yield of 83%. The mass spectrometry results of the obtained sample are: HR-MS (APCI): m / z 543.2562 [M+H] + ; C 40 H 33 NO (%) calculated value: C, 88.3633; H, 6.1180; N, 2.5762; O, 2.9426; found value (%): C, 88.3691; H, 6.1120; N, 2.5737; O, 2.9452.

[0219] Synthesis of compound 1-28:

[0220]

[0221] Under nitrogen protection, intermediate 1-a (8.2 g, 0.02 mol), 3,5-diphenyltriazine phenylboronic acid (5.5 g, 0.02 mol), Pd(PPh 3 ) 4 (tetrakis(triphenylphosphine)palladium, 0.5 g, 0.4 mmol), K 2 CO 3 (potassium carbonate, 8.3 g, 0.06 mol), TBAB (tetrabutylammonium bromide, 0.3 g, 1 mmol), toluene (80 mL), ethanol (40 mL), water (20 mL), heated to 76 ° C, stirred for 6 hours, cooled to room temperature, washed with water until neutral, the organic phase was dried with anhydrous magnesium sulfate, passed through a silica gel column, and then recrystallized and purified with THF to obtain 9.5 g of compound 1-28, with a yield of 78%. The mass spectrometry results of the obtained sample are: HR-MS (APCI): m / z 607.2624 [M+H] + ; C 43 H 33 N 3Calculated value for O (%): C, 84.9802; H, 5.4732; N, 6.9141; O, 2.6325; Found value (%): C, 84.9882; H, 5.4633; N, 6.9114; O, 2.6371.

[0222] Synthesis of compound 2-11:

[0223]

[0224] The synthesis of compound 2-11 was based on the synthesis method of compound 1-1, except that intermediate 1-a and diphenylamine were replaced by intermediate 2-a and 4-anilinobiphenyl with fully deuterated benzene ring, with a yield of 79%; the deuterium band rate of the obtained sample was 85.6%, and the results of mass spectrometry detection were: HR-MS (APCI): m / z 593.1259 [M+H] + .

[0225] Synthesis of compound 2-13:

[0226]

[0227]

[0228] The synthesis of compound 2-13 was carried out according to the synthesis method of compound 1-1, except that intermediate 1-a and diphenylamine were replaced by intermediate 2-a and intermediate 3; the mass spectrometry result of the obtained sample was: HR-MS (APCI): m / z 607.2147 [M+H] + ; C 43 H 29 O 3 Calculated value of N (%): C, 84.9869; H, 4.8102; N, 2.3049; O, 7.8980; Found value (%): C, 84.9891; H, 4.8090; N, 2.3052; O, 7.8967.

[0229] Synthesis of compound 3-10:

[0230]

[0231]

[0232] The synthesis of intermediate 1, intermediate 2 and compound 3-10 all refer to the synthesis method of compound 1-1, and the corresponding intermediate raw materials are selected for synthesis. The mass spectrometry result of the final compound 3-10 is: HR-MS (APCI): m / z 835.3563 [M+H] + ; C 61 H 45 ON 3(%) Calculated value: C, 87.6347; H, 5.4255; N, 5.0261; O, 1.9136; Found value (%): C, 87.6391; H, 5.4202; N, 5.0252; O, 1.9155.

[0233] With reference to the synthesis methods of compound 1-1 and compound 1-28, all compounds in the present invention can be synthesized. The only difference is that different parent core intermediates and intermediates corresponding to the modifying groups need to be used to replace the products, and the mass amount of the intermediates is changed according to the molar amount. The replacement relationship between the parent core intermediates and the intermediates corresponding to the modifying groups, reactants and compounds is shown in Table 1.

[0234] Table 1 The substitution relationship between the intermediates, reactants and compounds corresponding to the parent core intermediates and the modified groups

[0235]

[0236] The performance parameters (including HOMO energy level and LUMO energy level, triplet energy T 1 The results are shown in Table 2.

[0237] Table 2 Performance parameter measurement results of compounds and existing materials

[0238]

[0239] Note: Highest occupied molecular orbital (HOMO) and lowest unoccupied molecular orbital (LUMO), triplet energy T 1 The data were obtained by simulation calculation in Gaussian 09 software. The calculation method adopted B3LYP hybrid functional and basis set 6-31g(d); Eg = absolute value of HOMO-LUMO.

[0240] As can be seen from Table 2, the compounds provided by the present invention have suitable triplet energy and HOMO / LUMO energy levels, which are beneficial to the transport of carriers and the transfer of energy in OLED devices. The compounds of the present invention are suitable for use as a second hole transport material or a phosphorescent host material.

[0241] Taking some compounds provided by the present invention as examples, they are respectively applied as the second hole transport material or the main material of the light-emitting layer in an organic electroluminescent device to verify the excellent effects achieved.

[0242] Example 1

[0243] This embodiment provides an organic electroluminescent device, the structure of which is as follows: Figure 1 As shown, it includes a substrate 1, an anode layer 2, a hole injection layer 3, a first hole transport layer 4, a second hole transport layer 5, a light emitting layer 6, a hole blocking layer 7, an electron transport layer 8, an electron injection layer 9 and a cathode layer 10 which are stacked in sequence.

[0244] Among them, the substrate 1 is a glass substrate with a thickness of 0.7 mm, the material of the anode layer 2 is indium tin oxide (ITO) with a high work function, the material of the hole injection layer 3 is HAT-CN with a thickness of 5 nm; the material of the first hole transport layer 4 is HT1 with a thickness of 60 nm; the material of the second hole transport layer 5 is compound 1-1 with a thickness of 10 nm; the light-emitting layer 6 uses GD01 as the light-emitting material and CBP as the main material, with a doping mass ratio of 6% and a thickness of 30 nm; the material of the hole blocking layer 7 is HB1 with a thickness of 10 nm; the material of the electron transport layer 8 is ET1 with a thickness of 35 nm; the material of the electron injection layer 9 is Liq with a thickness of 2 nm; the material of the cathode layer is Al with a thickness of 100 nm.

[0245] The basic material structure used in each functional layer of the device is as follows:

[0246]

[0247]

[0248]

[0249] The specific preparation steps of the above organic electroluminescent device are as follows:

[0250] (1) Clean the ITO anode layer on the transparent glass or plastic substrate by ultrasonic cleaning with deionized water, acetone, and ethanol for 20 minutes each, and then perform plasma treatment in an oxygen atmosphere for 5 minutes;

[0251] (2) On the ITO anode layer, the hole injection layer material HAT-CN is deposited by vacuum evaporation with a thickness of 5 nm. This layer serves as the hole injection layer.

[0252] (3) Vacuum evaporation of hole transport material HT1 on the hole injection layer with a thickness of 60 nm, which serves as the first hole transport layer;

[0253] (4) Vacuum evaporation is performed on the first hole transport layer HT1 to deposit a hole transport material compound 1-1 with a thickness of 15 nm. This layer serves as the second hole transport layer;

[0254] (5) On the second hole transport layer, a light-emitting layer was co-deposited by vacuum evaporation, using CBP as the main material and GD01 as the doping material, with a doping mass ratio of 6% and a thickness of 30 nm;

[0255] (6) On the light-emitting layer, a hole blocking material HB1 is deposited by vacuum evaporation with a thickness of 10 nm. This layer serves as a hole blocking layer.

[0256] (7) On the hole blocking layer, the electron transport material ET1 is evaporated by vacuum evaporation with a thickness of 35 nm. This layer serves as the electron transport layer;

[0257] (8) On the electron transport layer, the electron injection material Liq is evaporated by vacuum evaporation with a thickness of 2 nm. This layer serves as the electron injection layer;

[0258] (9) On the electron injection layer, cathode Al is deposited by vacuum evaporation with a thickness of 100 nm. This layer is used as a cathode conductive electrode and is referred to as the cathode layer.

[0259] Embodiment 2~25

[0260] The preparation process of Examples 2 to 25 is the same as that of Example 1, except that the second hole transport material uses compound 1-8, compound 1-13, compound 1-41, compound 2-2, compound 2-6, compound 2-11, compound 2-13, compound 2-34, compound 2-39, compound 3-7, compound 3-11, compound 3-17, compound 3-20, compound 3-22, compound 3-24, compound 3-35, compound 3-38, compound 3-46, compound 3-54, compound 4-1, compound 4-6, compound 4-34, compound 4-43, and compound 4-49 synthesized in the preparation example of the present invention instead of compound 1-1.

[0261] Comparative Example 1

[0262] Comparative Example 1 is the same as Example 1, except that the second hole transport material uses compound HT2 instead of compound 1-1.

[0263] The cathode and anode of each group of organic electroluminescent devices were connected by a known driving circuit, and the voltage-efficiency-current density relationship of the OLED device was tested by a standard method using a Keithley 2400 power supply combined with a PR670 photometer; the life of the device was tested by a constant current method under the test condition of a constant current density of 10 mA / cm 2 The time it takes for the brightness to decay to 95% of the initial brightness is the LT95 life of the device. The results are shown in Table 3.

[0264] Table 3 Comparison of performance results of organic electroluminescent devices in each group

[0265]

[0266] As can be seen from Table 3, the compounds provided by the present invention are applied as hole transport materials in OLED green light devices, and the performance is improved. For example, compared with HT2 in the comparative example, the compound 2-6 in Example 6 as a hole transport material has improved energy transmission capacity, and the luminous efficiency and service life are significantly improved, with the brightness efficiency increased by 42% and the service life increased by 98%.

[0267] Embodiment 26

[0268] The substrate 1 is a glass substrate with a thickness of 0.7 mm. The material of the anode layer 2 is indium tin oxide (ITO) with a high work function. The material of the hole injection layer 3 is HAT-CN with a thickness of 5 nm. The material of the first hole transport layer 4 is HT1 with a thickness of 60 nm. The material of the second hole transport layer 5 is TCTA with a thickness of 10 nm. The light-emitting layer 6 uses RD01 as the light-emitting material and the compound 1-20 of the present invention as the main material, with a doping mass ratio of 6% and a thickness of 30 nm. The material of the hole blocking layer 7 is HB1 with a thickness of 10 nm. The material of the electron transport layer 8 is ET1 with a thickness of 35 nm. The material of the electron injection layer 9 is Liq with a thickness of 2 nm. The material of the cathode layer is Al with a thickness of 100 nm.

[0269] The specific preparation steps are as follows:

[0270] (1) Clean the ITO anode layer on the transparent glass or plastic substrate by ultrasonic cleaning with deionized water, acetone, and ethanol for 20 minutes each, and then perform plasma treatment in an oxygen atmosphere for 5 minutes;

[0271] (2) On the ITO anode layer, the hole injection layer material HAT-CN is deposited by vacuum evaporation with a thickness of 5 nm. This layer serves as the hole injection layer.

[0272] (3) Vacuum evaporation of hole transport material HT1 on the hole injection layer with a thickness of 60 nm, which serves as the first hole transport layer;

[0273] (4) Vacuum evaporation of hole transport material TCTA with a thickness of 15 nm is performed on the first hole transport layer HT1, and this layer serves as the second hole transport layer;

[0274] (5) On the second hole transport layer, a light-emitting layer was co-deposited by vacuum evaporation, using compound 1-20 as the main material and RD01 as the doping material, with a doping mass ratio of 6% and a thickness of 30 nm;

[0275] (6) On the light-emitting layer, a hole blocking material HB1 is deposited by vacuum evaporation with a thickness of 10 nm. This layer serves as a hole blocking layer.

[0276] (7) On the hole blocking layer, the electron transport material ET1 is evaporated by vacuum evaporation with a thickness of 35 nm. This layer serves as the electron transport layer;

[0277] (8) On the electron transport layer, the electron injection material Liq is evaporated by vacuum evaporation with a thickness of 2 nm. This layer serves as the electron injection layer;

[0278] (9) On the electron injection layer, cathode Al is deposited by vacuum evaporation with a thickness of 100 nm. This layer is used as a cathode conductive electrode and is referred to as the cathode layer.

[0279] Embodiments 27 to 38

[0280] The preparation process of Examples 27 to 38 is the same as that of Example 26, except that the main material of the light-emitting layer uses Compound 1-24, Compound 1-26, Compound 1-28, Compound 1-32, Compound 1-36, Compound 2-28, Compound 2-36, Compound 2-37, Compound 2-44, Compound 4-26, Compound 4-32, and Compound 4-36 synthesized in the preparation example of the present invention instead of Compound 1-20.

[0281] Comparative Example 2

[0282] The preparation process of Comparative Example 2 is the same as that of Example 26, except that the main material of the light-emitting layer is replaced by Compound H1 synthesized in the preparation example of the present invention instead of Compound 1-20.

[0283] The cathode and anode of each group of organic electroluminescent devices were connected by a known driving circuit, and the voltage-efficiency-current density relationship of the OLED device was tested by a standard method using a Keithley 2400 power supply combined with a PR670 photometer; the life of the device was tested by a constant current method under the test condition of a constant current density of 10 mA / cm 2 The time it takes for the brightness to decay to 95% of the initial brightness is the LT95 life of the device. The results are shown in Table 4.

[0284] Table 4 Comparison of performance results of organic electroluminescent devices in each group

[0285]

[0286] As can be seen from Table 4, the compounds provided by the present invention are applied to OLED red light devices as the main materials of the light-emitting layer, and the performance is also improved. For example, when compound 2-37 in Example 34 is used as the main material, compared with H1 in the comparative example, the luminous efficiency and service life are significantly improved, the brightness efficiency is increased by 50%, and the service life is increased by 83%. When the compounds of other embodiments are used as the main materials, the luminous efficiency and life are significantly improved. The compounds described in the present invention can all be used as the main materials of the light-emitting layer. In order to achieve better luminous effects, compounds 3-1 to 3-70 are more suitable as hole transport materials. It can be seen that the efficiency and life of the device are well performed by selecting the compounds of the present invention, and the synthesis process of the material is simple, which has great application value in the application of OLED devices and has good industrialization prospects.

[0287] As described above, the basic principle, main features and advantages of the present invention are well described. The above embodiments and descriptions are only descriptions of preferred implementations of the present invention, and the present invention is not limited to the above embodiments. Without departing from the spirit and scope of the present invention, various changes and improvements made by ordinary technicians in this field to the technical solution of the present invention should fall within the protection scope determined by the present invention.

Claims

1. A compound, characterized in that Having a structure as shown in Formula 1, ； Wherein, T in Formula 1 is selected from one of C and Si; Y in Formula 1 is selected from one of O, S, C(R3)2, and NAr3; In the formula 1, m and n are independently selected from any value of 0, 1, 2, 3, and 4; Ar1 and Ar2 in Formula 1 are independently selected from any one of a heteroaryl group or an aromatic amine group; R1 and R2 in Formula 1 are independently selected from a methyl group and a phenyl group; when R1 and R2 are both benzene rings, they can be connected to form a fluorene ring; R3 in C(R3)2 is selected from methyl and phenyl; Ar3 in the NAr3 is selected from one of benzene, biphenyl and terphenyl; When m>1, the plurality of Ar1 are the same or different from each other; when n>1, the plurality of Ar2 are the same or different from each other; Ar1, Ar 2、 Any hydrogen atom in NAr3 can be replaced by deuterium; The heteroaryl group is selected from any one of the following structures, ； The aromatic amine group is selected from any one of the following structures, 。 2. The compound according to claim 1, characterized in that The compound has a structure as shown in Formula 2 to Formula 6, 。 3. A compound, characterized in that Has the following structure, 。 4. A compound, characterized in that Has the following structure, 。 5. Use of the compound according to any one of claims 1 to 4 in an organic electroluminescent device.

6. Use of the compound according to any one of claims 1 to 4 in an organic electroluminescent device.

7. Use of the compound according to any one of claims 1 to 4 in the preparation of hole transport materials or phosphorescent host materials.

8. An organic electroluminescent device, comprising an anode layer, a cathode layer and an organic thin film layer located between the anode layer and the cathode layer, wherein the organic thin film layer comprises a hole injection layer, a first hole transport layer, a second hole transport layer, a light emitting layer, a hole blocking layer, an electron transport layer and an electron injection layer, characterized in that: The light-emitting layer contains the compound according to any one of claims 1 to 4.

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