A compound containing a pyranoquinoxalin structure and application thereof

Abstract

This invention relates to a compound containing a pyranoquinoxaline structure and its applications, belonging to the field of organic electroluminescent materials technology. The compound containing the pyranoquinoxaline structure has the following structural formula: Ar is selected from aromatic hydrocarbon groups with 6-30 carbon atoms (deuterated or undeuterated) and heteroaryl groups with 5-30 carbon atoms (deuterated or undeuterated), wherein the heteroatoms in the heteroaryl group are selected from N, S, and O. The compound containing the pyranoquinoxaline structure is used in organic electroluminescent devices. The compound containing the pyranoquinoxaline structure of this invention, used as a host material and electron transport material in organic electroluminescent devices, can restrict carrier flow within the light-emitting layer, providing better device performance, including lower driving voltage, higher current efficiency, and extended lifespan. It significantly improves device lifespan and has good application effects in OLED light-emitting devices, showing promising industrialization prospects.

Description

Technical Field

[0001] This invention relates to a compound containing a pyranoquinoxaline structure and its applications, belonging to the field of organic electroluminescent materials technology. Background Technology

[0002] Since 2000, OLED has been hailed as the third-generation display technology, attracting significant attention from the industry due to its superior performance unmatched by other display technologies. The rapid development of information science and technology has led to increasingly higher demands on information display devices, particularly high-quality images (high resolution, high contrast, high response speed, wide viewing angle) and portability (ultra-thin, ultra-light, low power consumption), which have become the future direction of information display development. OLED precisely meets all these requirements.

[0003] OLEDs, as electroluminescent materials with a very different light-emitting mechanism, emit light under the action of an electric field. This is a light-emitting process that directly converts electrical energy into light energy.

[0004] Compared to other display technologies, OLEDs possess numerous advantages, such as a wide range of material choices, high luminous brightness and efficiency, full-color display across the blue to red light spectrum, wide viewing angles, low driving voltage, relatively simple manufacturing process, and low cost. Most notably, they enable flexible displays. OLEDs can meet the demands of today's information age for higher performance and greater information capacity in display devices, making the development of higher-performance OLED materials imperative. Summary of the Invention

[0005] To address the shortcomings of existing technologies, this invention provides a compound containing a pyranoquinoxaline structure and its application. The compound containing the pyranoquinoxaline structure, when used in the organic layer of an organic electroluminescent device, can improve luminous efficiency and extend the device's lifespan.

[0006] The technical solution of the present invention to solve the above-mentioned technical problems is as follows: a compound containing a pyranoquinoxaline structure, wherein the structural formula of the compound containing the pyranoquinoxaline structure is as follows:

[0007] ;

[0008] Ar is selected from aromatic hydrocarbon groups with 6 to 30 carbon atoms, whether deuterated or undeuterated, and heteroaryl groups with 5 to 30 carbon atoms, wherein the heteroatoms in the heteroaryl group are selected from N, S, and O.

[0009] Furthermore, the Ar is selected from any one of phenyl, biphenyl, naphthyl, phenanthrene, triphenylene, fluoranthyl, benzanthyl, terphenyl, pyrene, 9,9-dimethylfluorenyl, dibenzofuranyl, dibenzothiopheneyl, N-phenylcarbazolyl, 9,9-diphenylfluorenyl, quinolinyl, 3,5-diphenyltriazinyl, benzo9,9-dimethylfluorenyl, deuterated carbazolyl, and isoquinolinyl.

[0010] Furthermore, the Ar group is selected from any one of the following groups:

[0011] .

[0012] Furthermore, the compound containing the pyranoquinoxaline structure is selected from the following compounds:

[0013] .

[0014] The present invention also discloses the application of a compound containing a pyranoquinoxaline structure, wherein the compound containing the pyranoquinoxaline structure is used in organic electroluminescent devices.

[0015] Furthermore, the organic electroluminescent device includes an anode and a cathode, and an organic layer disposed between the anode and the cathode, wherein the compound containing the pyranoquinoxaline structure is applied in the organic layer.

[0016] Furthermore, the organic layer includes at least a hole injection layer, a hole transport layer, a light-emitting layer, an electron transport layer, and an electron injection layer.

[0017] Furthermore, the material of the light-emitting layer comprises a host material and a guest material, wherein the host material comprises at least one of the compounds containing the pyranoquinoxaline structure.

[0018] Furthermore, the guest material is a phosphorescent dopant, which is a complex containing a transition metal.

[0019] Preferably, the phosphorescent dopant is an Ir complex or a Pt complex.

[0020] Furthermore, the electron transport layer comprises at least one of the compounds containing the pyranoquinoxaline structure.

[0021] The beneficial effects of this invention are:

[0022] The compound containing the pyranoquinoxaline structure described in this invention can be used as the main material and electron transport material for organic electroluminescent devices. It can restrict the flow of charge carriers in the light-emitting layer and provide better device performance, including lower driving voltage, higher current efficiency and extended lifespan. This results in a driving voltage of less than 3.70V and a current efficiency of not less than 28Cd / A. At the same time, it significantly improves the device lifespan and has good application effects in OLED light-emitting devices, showing good industrialization prospects. Attached Figure Description

[0023] Figure 1 This is a schematic diagram of the structure of the OLED device described in this invention;

[0024] In the figure, 1 is the glass substrate; 2 is the anode layer; 3 is the hole injection layer; 4 is the hole transport layer; 5 is the light-emitting layer; 6 is the electron transport layer; 7 is the electron injection layer; and 8 is the cathode layer. Detailed Implementation

[0025] To make the above-mentioned objects, features, and advantages of the present invention more apparent and understandable, specific embodiments of the present invention are described in detail below. Many specific details are set forth in the following description to provide a thorough understanding of the present invention. However, the present invention can be practiced in many other ways different from those described herein, and those skilled in the art can make similar modifications without departing from the spirit of the present invention. Therefore, the present invention is not limited to the specific embodiments disclosed below.

[0026] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains. The terminology used herein in the description of the invention is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention.

[0027] The preparation method of the compound containing the pyranoquinoxaline structure described in this invention is as follows:

[0028] ;

[0029] Intermediates are denoted as Intermediate A, Intermediate B, and Intermediate C, while host compounds are denoted as Host A and Host B; X is a halogen, such as Cl, Br, or I.

[0030] 1. Intermediate A uses 2-chloro-3-fluoroquinoxaline (CAS: 303762-31-4) as the starting material. The specific synthesis method: Add 2-chloro-3-fluoroquinoxaline (30 g, 164.3 mmol), bis(pinacolato)diboron 41.7 g (164.3 mmol), potassium acetate 24.2 g (246.5 mmol), toluene 250 mL, and tetrakis(triphenylphosphine)palladium 0.949 g (0.821 mmol) into the system. Heat the system to 90 - 100 °C and react for 5 h. After hydrolysis, washing with water, and solvent removal, recrystallize with 2 times the weight of toluene to obtain 37.2 g of Intermediate A. GC (Intermediate A): 99.7%, yield 82.6%.

[0031] Elemental analysis structure: The molecular formula is C 14 H 16 BFN2O2; LC-MS product molecular weight: 274.7, the theoretical molecular weight of the product is 274.10; 1H NMR (400 MHz): 7.66 - 7.85 (2H, 7.74 (ddd), 7.78 (ddd)), 8.02 - 8.21(2H, 8.08 (ddd), 8.15 (ddd)).

[0032] 2. Intermediate B uses Intermediate A and 2-chloro-3-iodo-4-bromopyridine (CAS: 916203-52-6) as the main raw materials. Add 2-chloro-3-iodo-4-bromopyridine 30 g (94.2 mmol), potassium carbonate 26 g (188.5 mmol), toluene 300 g (303.4 ml), water 60.7 mL, and tetrakis(triphenylphosphine)palladium 0.5442 g (0.4712 mmol) into a 500 mL three-necked flask filled with nitrogen. Stir and heat to 60 - 65 °C, then start to dropwise add the tetrahydrofuran solution of Intermediate A (25.8 g (94.2 mmol) of Intermediate A dissolved in 60 mL of tetrahydrofuran). After the dropwise addition, control the temperature at 60 - 65 °C and react. Take a sample to track GC after reacting for 4 h. Keep the temperature for 4 h and the reaction is qualified. GC detection: The content of 2-bromo-5-chloro-6-fluoroiodobenzene is 0.25%, and the content of Intermediate B is 95.6%. After the reaction is qualified, separate the layers, wash with water, and pass through a silica gel column to obtain the target product B 25.1 g. GC: 98.5%, yield 78.6%.

[0033] Elemental analysis structure: The molecular formula is C 13H6BrClFN3; GC-MS analysis of product molecular weight: 337.8, theoretical molecular weight of product is 338.56; 1H NMR (400 MHz): δ7.57 (1H, d), 7.70-7.89 (2H (ddd), 7.82 (ddd)), 8.08-8.32 (3H, 8.14 (ddd), 8.24 (d), 8.25 (ddd)).

[0034] 3. Intermediate C was prepared using intermediate B as the main raw material. 30 g (88.6 mmol) of intermediate B and 250 mL of tetrahydrofuran were added to a 500 mL three-necked flask filled with nitrogen. The system was then cooled to below -80 °C, and 93 mmol of n-butyllithium was added dropwise. After the addition was complete, the reaction was carried out at -85 °C for 1 h. Then, 17.8 g (97.5 mmol) of tetrahydrofuran solution of benzophenone was added dropwise to the system, and the reaction was maintained at this temperature for 1 h. After hydrolysis, extraction, washing with water, solvent removal, and recrystallization with petroleum ether, 33.3 g of intermediate C was obtained, with an LC of 98.9% and a yield of 85%.

[0035] Elemental analysis of the structure: The molecular formula is C 26 H 17 ClFN3O; LC-MS analysis of the product molecular weight: 441.3, theoretical molecular weight of the product is 441.89; 1H NMR (400 MHz): δ 7.24-7.42 (6H, 7.31 (tt), 7.35 (dddd)), 7.63 (1H), 7.74-7.99 (6H, 7.81 (ddd), 7.81 (ddd), 7.93 (dddd)), 8.10-8.30 (2H, 8.16 (ddd), 8.23 ​​(ddd)), 8.47 (1H).

[0036] 4. Using intermediate C as raw material, 30g (67.9mmol) of intermediate C, 18.7g (135.8mmol) of potassium carbonate, and 250mL of DMF were added to a 500mL three-necked flask filled with nitrogen. The system was slowly heated to 120-125℃ and reacted for 2 hours. The LC (intermediate C) was monitored and found to be ≤1%, which was acceptable. After the reaction was qualified, the intermediate C was hydrolyzed, extracted, washed with water, and passed through a column. The resulting product was recrystallized to obtain 20.8g of main structure A, with a yield of 72.7%.

[0037] Elemental analysis of the structure: The molecular formula is C 26 H 16ClN3O; LC-MS analysis of the product molecular weight: 421.31, theoretical molecular weight of the product is 421.88; 1H NMR (400 MHz): δ 7.14-7.43 (10H, 7.21 (dddd), 7.32 (tt), 7.36 (dddd)), 7.61-7.86 (3H, 7.66 (d), 7.78 (ddd), 7.79 (ddd)), 8.03-8.26 (2H, 8.09 (ddd), 8.19 (ddd)), 8.45 (1H, d).

[0038] 5. Using main structure A as raw material, 30 g (71.1 mmol) of main structure A, 19.9 g (78.2 mmol) of pinacol diborate, 10.5 g (106.7 mmol) of potassium acetate, 250 mL of toluene, 0.0798 g (0.355 mmol) of palladium acetate, and 0.1865 g (71.1 mmol) of triphenylphosphine were added to a 500 mL three-necked flask filled with nitrogen. The system was heated to 100–105 °C and reacted for 5 h. After hydrolysis, washing with water, and solvent removal, 30.1 g of main structure B was obtained by recrystallization from 2 times the amount of toluene. LC (main structure B): 99.5%, yield 82.5%.

[0039] Elemental analysis of the structure: The molecular formula is C 32 H 28 BN3O3; LC-MS analysis of product molecular weight: 513.8, theoretical molecular weight of product is 513.40; 1H NMR (400 MHz): δ 1.38 (12H, s), 7.14-7.43 (10H, 7.21 (dddd), 7.32 (tt), 7.36 (dddd)), 7.63 (1H, d), 7.72-7.97 (2H, 7.79 (ddd), 7.89 (ddd)), 8.11-8.33 (2H, 8.17 (ddd), 8.27 (ddd)), 8.78 (1H, d).

[0040] 6. The final compound is obtained by reacting the main structure A and arylboronic acid as the main raw materials, with toluene and tetrahydrofuran as solvents, and palladium acetate / tri-tert-butylphosphine, tetra(triphenylphosphine)palladium or tris(dibenzylideneacetone)bispalladium (hereinafter referred to as Pd2(dba)3) / 2-dicyclohexylphosphine-2',4',6'-triisopropylbiphenyl (hereinafter referred to as X-PHOS) as catalysts, with potassium carbonate aqueous solution providing an alkaline environment, and the reaction is carried out at a controlled temperature of 70-80℃ to obtain the final product; or by reacting the main structure B and haloaromatic hydrocarbons as the main raw materials, with toluene as the solvent, and palladium acetate / triphenylphosphine, tetra(triphenylphosphine)palladium or Pd2(dba)3 / X-PHOS as catalysts, with potassium carbonate aqueous solution providing an alkaline environment, and the reaction is carried out at a controlled temperature of 70-80℃ to obtain the final product.

[0041] Example 1

[0042] Preparation of compound 1:

[0043] ;

[0044] Synthesis of Compound 1: 42.2 g of main component A, 12.2 g of phenylboronic acid, 27.6 g of potassium carbonate, 64.4 g of water, 450 g of toluene, and 0.5775 g of tetra(triphenylphosphine)palladium were added to a 1 L three-necked flask. The mixture was stirred and heated to 75 °C under a nitrogen atmosphere. The reaction was completed in 3 h. After the reaction, the system separated into layers. The organic phase was washed with water, desolventized, recrystallized multiple times from toluene, and dried to obtain 34.3 g of Compound 1. HPLC: 99.98%, yield 74%.

[0045] Elemental analysis of the structure: The molecular formula is C 32 H 21 N3O; LC-MS analysis of product molecular weight: 463.81, theoretical molecular weight of product is 463.54; 1H NMR (400 MHz): δ 7.14-7.43 (10H, 7.21 (dddd), 7.29 (tt), 7.36 (dddd)), 7.48-8.02 (8H, 7.56 (tt), 7.69 (dddd), 7.80 (ddd), 7.81 (d), 7.89 (ddd), 7.96 (ddddz)), 8.11-8.30 (2H, 8.17 (ddd), 8.24 (ddd)), 8.88 (1H, d).

[0046] Example 2

[0047] Preparation of compound 11:

[0048] ;

[0049] Synthesis of Compound 11: 42.2 g of main structure A, 22.2 g of 9-phenanthroline boric acid, 27.6 g of potassium carbonate, 64.4 g of water, 450 g of toluene, and 0.5775 g of tetra(triphenylphosphine)palladium were added to a 1 L three-necked flask. The mixture was stirred and heated to 75 °C under a nitrogen atmosphere. The reaction was completed in 3 h. After the reaction, the system separated into layers. The organic phase was washed with water, desolventized, recrystallized multiple times from toluene, and dried to obtain 31.6 g of solid Compound 11. HPLC: 99.97%, yield 56%.

[0050] Elemental analysis of the structure: The molecular formula is C 40 H 25 N3O; LC-MS analysis of product molecular weight: 563.12, theoretical molecular weight: 563.66; 1H NMR (400 MHz): δ 7.14-7.43 (10H, 7.21 (dddd), 7.29 (tt), 7.36 (dddd)), 7.59-8.07 (7H, 7.66 (dddd), 7.71 (ddd), 7.74 (ddd), 7.74 (ddd), 7.86 (ddd), 7.95 (d), 8.00 (ddd)), 8.11-8.57 (7H, 8.17 (dddd), 8.27 (dddd), 8.29 (ddd), 8.38 (ddd), 8.46 (dddd), 8.49 (dddd), 8.51 (ddddd)), 8.94 (1H, dz).

[0051] Example 3

[0052] Preparation of compound 16:

[0053] ;

[0054] Synthesis of Compound 16: 42.2 g of main component A, 27.4 g of 1,1':4',1” terphenyl-2-boronic acid, 27.6 g of potassium carbonate, 64.4 g of water, 450 g of toluene, and 0.5775 g of tetra(triphenylphosphine)palladium were added to a 1 L three-necked flask. The mixture was stirred and heated to 75 °C under a nitrogen atmosphere. The reaction was completed in 3 h. After the reaction, the system separated into layers. The organic phase was washed with water, desolventized, recrystallized multiple times from toluene, and dried to obtain 42.5 g of solid Compound 16. HPLC: 99.983%, yield 69%.

[0055] Elemental analysis of the structure: The molecular formula is C 44 H 29N3O; LC-MS analysis of product molecular weight: 615.2, theoretical molecular weight of product: 615.74; 1H NMR (400 MHz): δ 7.14-7.46 (11H, 7.21 (dddd), 7.29 (tt), 7.36 (dddd), 7.39 (tdd)), 7.61-7.90 (10H, 7.69 (dddd), 7.71 (ddd), 7.71 (dddd), 7.76 (ddd), 7.77 (ddd), 7.83 (ddd), 7.83 (d)), 7.94-8.48 (7H, 8.01 (ddd), 8.02 (ddd), 8.13 (ddd), 8.25 (ddd), 8.35 (ddd), 8.42 (ddd)), 8.90 (1H, d).

[0056] Example 4

[0057] Preparation of compound 18:

[0058] ;

[0059] Synthesis of Compound 18: 42.2 g of main component A, 24.6 g of 2-fluoranthraceneboronic acid, 27.6 g of potassium carbonate, 64.4 g of water, 450 g of toluene, and 0.5775 g of tetra(triphenylphosphine)palladium were added to a 1 L three-necked flask. The mixture was stirred and heated to 75 °C under a nitrogen atmosphere. The reaction was completed in 3 h. After the reaction, the system separated into layers. The organic phase was washed with water, desolventized, recrystallized multiple times from toluene, and dried to obtain 43.2 g of solid Compound 18. HPLC: 99.988%, yield 73.5%.

[0060] Elemental analysis of the structure: The molecular formula is C 42 H 25N3O; LC-MS analysis of product molecular weight: 587.81, theoretical molecular weight of product: 587.68; 1H NMR (400 MHz): δ 7.14-7.43 (10H, 7.21 (dddd), 7.29 (tt), 7.36 (dddd)), 7.61 (1H, d), 7.82-8.09 (5H, 7.89 (ddd), 7.90 (ddd), 7.97 (ddd), 8.02 (ddd), 8.03 (ddd)), 8.25-8.49 (5H, 8.31 (ddd), 8.36 (dd), 8.41 (ddd), 8.43 (ddd), 8.43 (ddd)), 8.69 (1H, d), 8.82-9.06 (3H, 8.88) (d), 8.92 (ddd), 9.00 (ddd)).

[0061] Example 5

[0062] Preparation of compound 33:

[0063] ;

[0064] Synthesis of compound 33: 42.2 g of main component A, 21.2 g of 2-dibenzofuranboronic acid, 27.6 g of potassium carbonate, 64.4 g of water, 450 g of toluene, and 0.5775 g of tetra(triphenylphosphine)palladium were added to a 1 L three-necked flask. The mixture was stirred and heated to 75 °C under a nitrogen atmosphere. The reaction was completed in 3 h. After the reaction, the system separated into layers. The organic phase was washed with water, desolventized, recrystallized multiple times from toluene, and dried to obtain 35.3 g of compound 33 solid. HPLC: 99.989%, yield 63.8%.

[0065] Elemental analysis of the structure: The molecular formula is C 38 H 23N3O2; LC-MS analysis of product molecular weight: 553.3, theoretical molecular weight of product: 553.62; 1H NMR (400 MHz): δ 7.14-7.43 (10H, 7.21 (dddd), 7.29 (tt), 7.36 (dddd)), 7.72-8.10 (7H, 7.79 (ddd), 7.90 (ddd), 7.91 (ddd), 7.92 (ddd), 7.95 (dd), 8.02 (ddd), 8.04 (d)), 8.16 (1H, dd), 8.23-8.45 (2H, 8.29 (ddd), 8.39 (ddd)), 8.54 (1H, dddd), 8.74-8.95 (2H, 8.79 (ddd), 8.89 (d)).

[0066] Example 6

[0067] Preparation of compound 37:

[0068] ;

[0069] Synthesis of compound 37: 42.2 g of main component A, 24.6 g of 1-pyreneboronic acid, 27.6 g of potassium carbonate, 64.4 g of water, 450 g of toluene, and 0.5775 g of tetra(triphenylphosphine)palladium were added to a 1 L three-necked flask. The mixture was stirred and heated to 75 °C under a nitrogen atmosphere. The reaction was completed in 3 h. After the reaction, the system separated into layers. The organic phase was washed with water, desolventized, recrystallized multiple times from toluene, and dried to obtain 44.9 g of compound 37 solid. HPLC: 99.971%, yield 76.4%.

[0070] Elemental analysis of the structure: The molecular formula is C 42 H 25 NO; LC-MS analysis of product molecular weight: 587.13, theoretical molecular weight: 587.68; 1H NMR (400 MHz): δ 7.14-7.43 (10H, 7.21 (dddd), 7.29 (tt), 7.36 (dddd)), 7.75-8.22 (5H, 7.82 (dddd), 7.91 (ddd), 7.97 (d), 8.04 (ddd), 8.16 (ddd)), 8.23-8.60 (8H, 8.29 (dddd), 8.34 (ddd), 8.42 (dddd), 8.43 (ddd), 8.46 (dddd), 8.51 (ddd), 8.52 (ddd), 8.53 (dddd)), 8.68 (1H, ddd), 8.92 (1H, d).

[0071] Example 7

[0072] Preparation of compound 41:

[0073] ;

[0074] Synthesis of compound 41: 42.2 g of main component A, 23.8 g of 9,9-dimethylfluorene-2-boronic acid, 27.6 g of potassium carbonate, 64.4 g of water, 450 g of toluene, and 0.5775 g of tetra(triphenylphosphine)palladium were added to a 1 L three-necked flask. The mixture was stirred and heated to 75 °C under a nitrogen atmosphere. The reaction was completed in 3 h. After the reaction, the system separated into layers. The organic phase was washed with water, desolventized, recrystallized multiple times from toluene, and dried to obtain 40.6 g of compound 41 solid. HPLC: 99.99%, yield 70%.

[0075] Elemental analysis of the structure: The molecular formula is C 41 H 29 NO; LC-MS analysis of product molecular weight: 579.9, theoretical molecular weight of product is 579.7; 1H NMR (400 MHz): δ 2.08 (6H, s), 7.14-7.52 (13H, 7.21 (dddd), 7.29 (tt), 7.33 (dd), 7.36 (dddd), 7.40 (ddd), 7.45 (ddd)), 7.66-7.99 (7H, 7.72 (dd), 7.79 (ddd), 7.82 (ddd), 7.85 (ddd), 7.85 (d), 7.88 (dd), 7.92 (ddd)), 8.22 (1H, ddd), 8.39 (1H, ddd), 9.00 (1H, d).

[0076] Example 8

[0077] Preparation of compound 48:

[0078] ;

[0079] Synthesis of compound 48: 42.2 g of main component A, 22.8 g of 3-dibenzothiophene boric acid, 27.6 g of potassium carbonate, 64.4 g of water, 450 g of toluene, and 0.5775 g of tetra(triphenylphosphine)palladium were added to a 1 L three-necked flask. The mixture was stirred and heated to 75 °C under a nitrogen atmosphere. The reaction was completed in 3 h. After the reaction, the system separated into layers. The organic phase was washed with water, desolventized, recrystallized multiple times from toluene, and dried to obtain 37.9 g of compound 48 solid. HPLC: 99.98%, yield 66.5%.

[0080] Elemental analysis of the structure: The molecular formula is C38 H 23 NOS; LC-MS analysis of product molecular weight: 569.23, theoretical molecular weight: 569.68; 1H NMR (400 MHz): δ 7.14-7.43 (10H, 7.21 (dddd), 7.29 (tt), 7.36 (dddd)), 7.65 (1H, d), 7.73-8.07 (5H, 7.79 (ddd), 7.92 (ddd), 7.92 (ddd), 7.99 (ddd), 8.01 (dd)), 8.23-8.36 (2H, 8.30 (ddd), 8.30 (ddd)), 8.55-8.76 (4H, 8.62 (dddd), 8.67 (ddd), 8.67 (ddd), 8.71 (dd)), 8.91 (1H, d).

[0081] Example 9

[0082] Preparation of compound 50:

[0083] ;

[0084] Synthesis of Compound 50: 42.2 g of main component A, 28.7 g of N-phenylcarbazole-3-boric acid, 27.6 g of potassium carbonate, 64.4 g of water, 450 g of toluene, and 0.5775 g of tetra(triphenylphosphine)palladium were added to a 1 L three-necked flask. The mixture was stirred and heated to 75 °C under a nitrogen atmosphere. The reaction was completed in about 3 hours. After the reaction, the system separated into layers. The organic phase was washed with water, desolventized, recrystallized multiple times from toluene, and dried to obtain 46.9 g of solid Compound 50. HPLC: 99.981%, yield 74.5%.

[0085] Elemental analysis of the structure: The molecular formula is C 44 H 28N4O; LC-MS analysis of product molecular weight: 628.5, theoretical molecular weight: 628.74; 1H NMR (400 MHz): δ 7.14-7.43 (10H, 7.21 (dddd), 7.29 (tt), 7.36 (dddd)), 7.52 (1H, tdd), 7.66-8.03 (10H, 7.73 (ddd), 7.73 (dddd), 7.79 (ddd), 7.91 (ddd), 7.92 (ddd), 7.93 (d), 7.95 (dd), 7.96 (dddd)), 8.22-8.57 (5H, 8.28 (dd), 8.29 (ddd), 8.40 (ddd), 8.40 (ddd), 8.51 (dddd)). 8.73-8.94 (2H, 8.79 (ddd), 8.88 (d)).

[0086] Example 10

[0087] Preparation of compound 71:

[0088] ;

[0089] Synthesis of Compound 71: 51.3 g of main component B, 26.8 g of 3,5-diphenyl-1-chlorotriazine, 27.6 g of potassium carbonate, 64.4 g of water, 450 g of toluene, and 0.5775 g of tetra(triphenylphosphine)palladium were added to a 1 L three-necked flask. The mixture was stirred and heated to 75 °C under a nitrogen atmosphere. The reaction was completed in 3 h. After the reaction, the system separated into layers. The organic phase was washed with water, desolventized, recrystallized multiple times from toluene, and dried to obtain 42.4 g of solid Compound 71. HPLC: 99.97%, yield 68.5%.

[0090] Elemental analysis of the structure: The molecular formula is C 41 H 26 N6O; LC-MS analysis of product molecular weight: 618.42, theoretical molecular weight of product is 618.70; 1H NMR (400 MHz): δ 7.15-7.56 (14H, 7.21 (dddd), 7.29 (tt), 7.36 (dddd), 7.49 (dddd)), 7.85-8.38 (11H, 7.92 (tdd), 7.98 (ddd), 8.00 (ddd), 8.11 (ddd), 8.21 (dddd), 8.28 (d), 8.32 (ddd)), 8.87 (1H, d).

[0091] Example 11

[0092] Preparation of compound 72:

[0093] ;

[0094] Synthesis of Compound 72: 42.2 g of main component A, 17.5 g of d8-carbazole, 13.2 g of potassium carbonate, 240 g of DMF, 2 g of cuprous iodide, and 1.8 g of N,N-dimethylethylenediamine were added to a 500 mL three-necked flask. The mixture was stirred and heated to 130 °C under a nitrogen atmosphere. The reaction was completed in about 15 h. After the reaction was completed, the system was filtered, and the organic phase was extracted, washed with water, desolventized, recrystallized from toluene, and dried to obtain 37.3 g of solid Compound 72. HPLC: 99.985%, yield 66.5%.

[0095] Elemental analysis of the structure: The molecular formula is C 38 H 16 D8N4O; LC-MS analysis of product molecular weight: 560.81, theoretical molecular weight of product: 560.69; 1H NMR (400 MHz): δ 7.14-7.43 (10H, 7.21 (dddd), 7.29 (tt), 7.36 (dddd)), 7.45-7.59 (4H, 7.52 (ddd), 7.52 (ddd)), 7.79-7.98 (5H, 7.87 (ddd), 7.88 (ddd), 7.87 (d), 7.92 (ddd)), 8.00-8.22 (3H, 8.06 (dddd), 8.16 (ddd)), 8.36 (1H, ddd), 8.82 (1H, d).

[0096] The following detailed description of the application effects of the OLED material synthesized in the present invention in devices is illustrated through device embodiments and device comparative examples. The device embodiments 1-11, device comparative examples 1, and device comparative examples 2 of the present invention have the same fabrication process as device embodiment 1, and use the same substrate material and electrode material. The electrode film thickness is also consistent. The difference lies in the variation of the light-emitting layer / electron transport layer (ETL) material in each device embodiment or comparative example.

[0097] Device Examples

[0098] OLEDs have the following layer structure: substrate ((ITO) coated glass substrate) / hole injection layer (HIL) / hole transport layer (HTL) / emitting layer (EML) / electron transport layer (ETL) / electron injection layer (EIL), and finally a cathode.

[0099] The specific materials used are shown in Table 1. The materials required to manufacture OLEDs are as follows:

[0100] ;

[0101] .

[0102] The structure of the organic electroluminescent device is as follows: Figure 1 As shown, the fabrication of the organic electroluminescent device includes the following steps:

[0103] (1) Substrate cleaning: The glass substrate 1 coated with ITO is ultrasonically treated in an aqueous cleaning agent (the composition and concentration of the aqueous cleaning agent are: ethylene glycol solvent ≤10wt%, triethanolamine ≤1wt%), rinsed in deionized water, ultrasonically degreased in a mixed solvent of acetone: ethanol (volume ratio 1:1), baked in a clean environment until all moisture is removed, and then cleaned with ultraviolet light and ozone.

[0104] (2) Evaporation of organic light-emitting functional layer:

[0105] The glass substrate 1 with the anode layer 2 was placed in a vacuum chamber and evacuated to a vacuum level of 1×10⁻⁶. -6 Up to 2×10 -4 Pa, PD is vacuum-deposited on the anode layer 2 as a hole injection layer 3 with a deposition thickness of 5 nm; a hole transport layer 4 is vacuum-deposited on the hole injection layer 3 with a deposition thickness of 80 nm; a light-emitting layer 5 is vacuum-deposited on the hole transport layer 4, specifically prepared by co-evaporating the light-emitting host material and guest material in a vacuum method with a total deposition thickness of 30 nm; an electron transport layer 6 is vacuum-deposited on the light-emitting layer 5, specifically prepared by co-evaporating Bphen and LiQ in a vacuum method with a total deposition thickness of 30 nm; an electron injection layer 7 is vacuum-deposited on the electron transport layer 6 with a total deposition thickness of 1 nm; Mg:Ag is vacuum-deposited on the electron injection layer 7 with a total deposition thickness of 80 nm, forming the cathode layer 8. The parameters of each layer, its materials, and thickness in the device are shown in Table 1.

[0106] Table 1. Materials and thicknesses of each layer in the device

[0107]

[0108] Device performance testing:

[0109] Instrumentation: The current, voltage, brightness, and emission spectrum characteristics of the device were simultaneously tested using a PR 650 spectral scanning luminance meter and a Keithley K 2400 digital source meter system; Test conditions: current density of 10 mA / cm². 2 At room temperature. Lifetime test: Record the time (in hours) when the device brightness drops to 95% of its original brightness.

[0110] The device performance test results are shown in Table 2:

[0111] Table 2 Device performance test results

[0112]

[0113] As shown in Table 2, when the compounds containing the pyranoquinoxaline structure of the present invention are used as the main material of organic electroluminescent devices, or simultaneously as the light-emitting layer material and the electron transport layer material, they can reduce the driving voltage, improve the luminous efficiency, and extend the lifespan of the device, so that the driving voltage of the device is below 3.70V, the current efficiency is not less than 28Cd / A, and the lifespan is not less than 420h.

[0114] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0115] The embodiments described above are merely illustrative of several implementations of the present invention, and while the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the invention patent. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of the present invention, and these all fall within the protection scope of the present invention. Therefore, the protection scope of this invention patent should be determined by the appended claims.

Claims

1. A compound containing a pyranoquinoxaline structure, characterized in that, The structural formula of the compound containing the pyranoquinoxaline structure is as follows: ； The Ar group is selected from any one of the following groups: 。 2. A compound containing a pyranoquinoxaline structure, characterized in that, The compound containing the pyranoquinoxaline structure is selected from the following compounds: 。 3. The application of a compound containing a pyranoquinoxaline structure according to any one of claims 1-2, characterized in that, The compounds containing the pyranoquinoxaline structure are used in organic electroluminescent devices.

4. The application of a compound containing a pyranoquinoxaline structure according to claim 3, characterized in that, The organic electroluminescent device includes an anode and a cathode, and an organic layer disposed between the anode and the cathode, wherein the compound containing a pyranoquinoxaline structure is applied in the organic layer.

5. The application of a compound containing a pyranoquinoxaline structure according to claim 4, characterized in that, The organic layer comprises at least a hole injection layer, a hole transport layer, a light-emitting layer, an electron transport layer, and an electron injection layer.

6. The application of a compound containing a pyranoquinoxaline structure according to claim 5, characterized in that, The material of the luminescent layer comprises a host material and a guest material, wherein the host material comprises at least one of the compounds containing the pyranoquinoxaline structure.

7. The application of a compound containing a pyranoquinoxaline structure according to claim 6, characterized in that, The guest material is a phosphorescent dopant, which is a complex containing a transition metal.

8. The application of a compound containing a pyranoquinoxaline structure according to claim 5, characterized in that, The electron transport layer comprises at least one of the compounds containing the pyranoquinoxaline structure.

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