A dibenzo[c,g]phenanthrene derivative and an organic electroluminescent device thereof

Abstract

The invention discloses a dibenzo[c,g]phenanthrene derivative and an organic electroluminescent device thereof. The dibenzo[c,g]phenanthrene derivative comprises a P-type compound and an N-type compound. When the P-type compound and the N-type compound are compositely co-evaporated as a main luminescent material and applied to a luminescent layer of an OLED device, a wider carrier recombination region can be formed while effectively balancing holes and electrons, thereby greatly improving the luminescent efficiency of the device; at the same time, the P-type compound can be used as a hole transport layer material, and the N-type compound can be used as an electron transport layer material, thereby realizing the integration of device main luminescence, hole transport, and electron transport, and can effectively simplify the device structure and reduce costs.

Description

Technical Field

[0001] The invention belongs to the technical field of organic light-emitting materials and semiconductors, and specifically relates to a dibenzo[c,g]phenanthrene derivative and an organic electroluminescent device thereof. Background Art

[0002] In recent years, organic light-emitting diodes (OLEDs) have become a hot research direction in the field of lighting and display due to their excellent properties such as self-luminescence, high brightness, high contrast, see-through, wearable, foldable, low energy consumption, wide viewing angle, and low temperature resistance.

[0003] A typical OLED structure includes: an anode, a hole transport layer (HTL), an emission layer (EML), an electron transport layer (ETL), and a cathode. When voltage is applied to the anode and cathode, holes injected from the anode move to the EML through the HTL, and electrons injected from the cathode move to the EML through the ETL. Electrons and holes recombine in the EML to generate excitons. Excitons transfer energy to the luminescent material, and the luminescent material emits light.

[0004] In recent years, industry professionals have been continuously trying and exploring ways to improve the efficiency and stability of OLED devices, most of which seek new materials to improve device performance, so a large number of new materials have been developed for use in organic electroluminescent devices. With the continuous upgrading of electronic and lighting products, higher requirements have been placed on the optoelectronic performance of OLED devices, but existing OLED devices have the problem of large-scale accumulation of carriers at the interface, and the efficiency and life of the devices are still significantly insufficient.

[0005] Therefore, the art is in urgent need of developing organic electroluminescent materials with higher performance to meet market demand. Summary of the invention

[0006] In order to solve the above problems of the prior art, the present invention provides a dibenzo[c,g]phenanthrene derivative and an organic electroluminescent device thereof. The dibenzo[c,g]phenanthrene derivative can be used as a main luminescent material, an electron transport layer material or a hole transport layer material to prepare an electroluminescent device.

[0007] The present invention is achieved by the following technical solution: a dibenzo[c,g]phenanthrene derivative, the general structural formula of the dibenzo[c,g]phenanthrene derivative is as shown in general formula 1:

[0008] ;

[0009] in:

[0010] Ar1 is selected from C5~C 50 Aromatic secondary amines, C5~C 50The heteroaryl group, Ar1 is bonded to the main structure in a single bond manner; the heteroatom in the heteroaryl group is selected from a N atom, an O atom or a S atom.

[0011] Preferably, Ar1 includes any one of Y1 to Y40 substituents:

[0012] Y1, Y2, Y3, Y4, Y5, Y6, Y7, Y8, Y9, Y10, Y11, Y12, Y13, Y14, Y15, Y16, Y17, Y18, Y19, Y20, Y21, Y22, Y23, Y24, Y25, Y26, Y27, Y28, Y29, Y30, Y31, Y32, Y33, Y34, Y35, Y36, Y37, Y38, Y39, Y40.

[0013] Preferably, Ar1 includes any one of R1 to R49 substituents:

[0014] R1, R2, R3, R4, R5, R6, R7, R8, R9, R10, R11, R12, R13, R14, R15, R16, R17, R18, R19, R20, R21, R22, R23, R24, R25, R26, R27, R28, R29, R30, R31, R32, R33, R34, R35, R36, R37, R38, R39, R40, R41, R42, R43, R44, R45, R46, R47, R48, R49.

[0015] Preferably, an organic electroluminescent device comprises a cathode, an anode and an organic layer located between the cathode and the anode, wherein the organic layer comprises a hole transport layer, a light-emitting layer and an electron transport layer, and the organic layer material is selected from any one or more of compounds P1 to P84 and compounds N1 to N132.

[0016] Preferably, the material of the hole transport layer is selected from any one of compounds P1 to P84.

[0017] Preferably, the material of the electron transport layer is selected from any one of compounds N1 to N132.

[0018] Preferably, the material of the light-emitting layer is selected from any one or more of compounds P1 to P84 and compounds N1 to N132.

[0019] Preferably, the light-emitting layer includes a host light-emitting material and a guest light-emitting material, and the mass ratio of the host light-emitting material to the guest light-emitting material is 100:0.1~1, the host light-emitting material includes a P-type host light-emitting material and an N-type host light-emitting material, the P-type host light-emitting material is selected from any one of compounds P1~P84, the N-type host light-emitting material is selected from any one of compounds N1~N132, and the mass ratio of the P-type host light-emitting material to the N-type host light-emitting material is 40:60~30:70.

[0020] Preferably, the guest luminescent material is selected from , or .

[0021] Compared with the prior art, the present invention has the following beneficial effects:

[0022] (1) The present invention discloses a dibenzo[c,g]phenanthrene derivative and an organic electroluminescent device thereof. The dibenzo[c,g]phenanthrene derivative comprises a P-type compound and an N-type compound. When the P-type compound and the N-type compound are co-evaporated as the main luminescent material and applied to the luminescent layer of an OLED device, they can effectively balance the hole and electron carrier flows while forming a wider carrier recombination area, solving the problem of large-scale accumulation of carriers at the interface, thereby greatly improving the luminescent efficiency of the device; at the same time, the P-type compound can be used as a hole transport layer material, and the N-type compound can be used as an electron transport layer material, thereby realizing the integration of the device main body luminescence, hole transport, and electron transport, and can effectively simplify the device structure and reduce costs;

[0023] (2) The present invention uses a dibenzo[c,g]phenanthrene main structure as a skeleton. This structure is a strong fluorescent fragment. When it is matched with an electron-withdrawing substituent (R1-R49), it forms compounds N1-N132 (N-type compounds), which are used as N-type main luminescent materials; when it is matched with an electron-donating substituent (Y1-Y40), it forms compounds P1-P84 (P-type compounds), which are used as P-type main luminescent materials.

[0024] (3) The dibenzo[c,g]phenanthrene derivatives designed by the present invention have a large spatial stereo configuration. Due to their significant asymmetric configuration, they have excellent film-forming properties during molecular evaporation, which significantly improves the luminescence consistency, thereby effectively improving the device yield;

[0025] (4) The synthesis and preparation process of the dibenzo[c,g]phenanthrene derivatives disclosed in the present invention is simple, the raw materials are readily available, and it is easy to achieve large-scale and sustainable production and preparation of products. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] 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 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.

[0027] Figure 1 , a cross-sectional view of an organic electroluminescent device of the present invention;

[0028] Figure 2 , the NMR spectrum of compound P22 of the present invention;

[0029] Figure 3 , the NMR spectrum of compound N1 of the present invention;

[0030] Figure 4 , the NMR spectrum of compound N62 of the present invention;

[0031] Figure 5 , NMR spectrum of compound N94 of the present invention.

[0032] Description of reference numerals:

[0033] 01-substrate layer, 02-anode layer, 03-hole injection layer, 04-hole transport layer, 05-light-emitting layer, 06-electron transport layer, 07-electron injection layer, 08-cathode layer. DETAILED DESCRIPTION

[0034] The following describes the embodiments of the present invention through specific examples. Those skilled in the art can easily understand other advantages and effects of the present invention from the contents disclosed in this specification. The present invention can also be implemented or applied through other different specific embodiments. The details in this specification can also be based on different viewpoints and applications. Various modifications or changes without departing from the spirit of the present invention are within the scope of the present invention.

[0035] It should be noted that the process equipment or devices not specifically specified in the following embodiments are all conventional equipment or devices in the art.

[0036] It should be noted that the terms "include" and "have" and any variations thereof are intended to cover non-exclusive inclusions. For example, a process, method, system, product or device that includes a series of steps or units is not necessarily limited to those steps or units clearly listed, but may include other steps or units that are not clearly listed or inherent to these processes, methods, products or devices. Moreover, unless otherwise specified, the numbering of each method step is only a convenient tool for identifying each method step, and is not intended to limit the order of arrangement of each method step or to define the scope of the present invention. Changes or adjustments in their relative relationships should also be regarded as the scope of the present invention without substantially changing the technical content.

[0037] A dibenzo[c,g]phenanthrene derivative, wherein the general structural formula of the dibenzo[c,g]phenanthrene derivative is shown in general formula 1:

[0038] ;

[0039] in:

[0040] Ar1 is selected from C5~C 50 Aromatic secondary amines, C5~C 50 The bonding mode of Ar1 to the main structure is a single bond;

[0041] The heteroatom in the heteroaryl group is selected from a N atom, an O atom or a S atom.

[0042] Preferably, Ar1 includes any one of Y1 to Y40 substituents:

[0043] Y1, Y2, Y3, Y4, Y5, Y6, Y7, Y8, Y9, Y10, Y11, Y12, Y13, Y14, Y15, Y16, Y17, Y18, Y19, Y20, Y21, Y22, Y23, Y24, Y25, Y26, Y27, Y28, Y29, Y30, Y31, Y32, Y33, Y34, Y35, Y36, Y37, Y38, Y39, Y40.

[0044] Preferably, Ar1 includes any one of R1 to R49 substituents:

[0045] R1, R2, R3, R4, R5, R6, R7, R8, R9, R10, R11, R12, R13, R14, R15, R16, R17, R18, R19, R20, R21, R22, R23, R24, R25, R26, R27, R28, R29, R30, R31, R32, R33, R34, R35, R36, R37, R38, R39, R40, R41, R42, R43, R44, R45, R46, R47, R48, R49.

[0046] The asterisk (*) in the above substituents indicates the substitution position.

[0047] Preferably, the dibenzo[c,g]phenanthrene derivatives include compounds P1-P84 and N1-N132, and the specific structural formulas are as follows:

[0048] ;

[0049] ;

[0050] ;

[0051] ;

[0052] ;

[0053] ;

[0054] ;

[0055] ;

[0056] ;

[0057] ;

[0058] ;

[0059] ;

[0060] ;

[0061] ;

[0062] ;

[0063] ;

[0064] ;

[0065] ；

[0066] ；

[0067] ；

[0068] ；

[0069] ；

[0070] ；

[0071] ；

[0072] ；

[0073] ；

[0074] ；

[0075] ；

[0076] ；

[0077] ；

[0078] ；

[0079] ；

[0080] ；

[0081] ；

[0082] ；

[0083] ；

[0084] ；

[0085] ；

[0086] ；

[0087] ；

[0088] ；

[0089] ；

[0090] ;

[0091] ;

[0092] ;

[0093] ;

[0094] ;

[0095] ;

[0096] ;

[0097] ;

[0098] ;

[0099] ;

[0100] ;

[0101] .

[0102] Preferably, an organic electroluminescent device comprises a cathode, an anode and an organic layer located between the cathode and the anode, wherein the organic layer comprises a hole transport layer, a light-emitting layer and an electron transport layer, and the organic layer material is selected from any one or more of compounds P1 to P84 and compounds N1 to N132.

[0103] Preferably, the material of the hole transport layer is selected from any one of compounds P1 to P84.

[0104] Preferably, the material of the electron transport layer is selected from any one of compounds N1 to N132.

[0105] Preferably, the material of the light-emitting layer is selected from any one or more of compounds P1 to P84 and compounds N1 to N132.

[0106] Preferably, the light-emitting layer includes a host light-emitting material and a guest light-emitting material, and the mass ratio of the host light-emitting material to the guest light-emitting material is 100:0.1~1, the host light-emitting material includes a P-type host light-emitting material and an N-type host light-emitting material, the P-type host light-emitting material is selected from any one of compounds P1~P84, the N-type host light-emitting material is selected from any one of compounds N1~N132, and the mass ratio of the P-type host light-emitting material to the N-type host light-emitting material is 40:60~30:70.

[0107] Preferably, the guest luminescent material is selected from , or .

[0108] The P-type compound, namely compounds P1 to P84, is used as a P-type main light-emitting material, and the N-type compound, namely compounds N1 to N132, is used as an N-type main light-emitting material.

[0109] The synthesis process of the dibenzo[c,g]phenanthrene derivatives is described as follows:

[0110] The synthesis process of key intermediates (M1, M2) in the implementation process is as follows:

[0111] 1. Synthesis steps of key intermediate M1:

[0112] ;

[0113] .

[0114] Synthesis of M1-1:

[0115] Under an inert atmosphere, 2-formylphenylboronic acid (450 g, 3.0 mol), 2-bromo-4-chloro-1-iodobenzene (952 g, 3.0 mol), potassium phosphate (1274 g, 6.0 mol), 10 L of 1,4-dioxane, 1.5 L of deionized water, and Pd(PPh3)4 (35 g, 0.03 mol) were added to a 20 L three-necked flask, and the system was heated to reflux, and the reaction was continued for 18 h. The reaction was completed. The reaction solution was first washed with water and separated, and the organic phase was passed through a diatomaceous earth funnel and the filtrate was collected and concentrated under reduced pressure to obtain a solid crude product. 3 L of ethyl acetate / petroleum ether solution in an appropriate ratio was added, dispersed and slurried, and filtered to obtain compound M1-1 (665 g, yield 75%), HPLC content 99%, LC-MS showed a molecular weight of 296.96.

[0116] Synthesis of M1-2:

[0117] Under an inert atmosphere, compound M1-1 (665 g, 2.25 mol), (methoxymethyl) triphenylphosphonium chloride (771 g, 2.25 mol), and 10 L of THF were added to a 20 L three-necked flask, and the temperature was lowered to below 0°C. 2000 ml of a THF solution of lithium bis(trimethylsilyl)amide (452 ​​g, 2.7 mol) was slowly added, and the reaction was continued at 0°C for 1 h until the reaction was completed. After the reaction was completed, 100 ml of ice water was slowly added for quenching, and most of the THF was removed by low temperature concentration. Then 5 L of saturated sodium bisulfate solution was added and stirred for 20 min, and then extracted with 2 L of ethyl acetate each time, extracted 3 times, combined the organic phases, dried over anhydrous sodium sulfate, concentrated, and recrystallized from ethyl acetate / petroleum ether to obtain compound M1-2 (583 g, yield 80%), HPLC content 99%, LC-MS showed a molecular weight of 324.96.

[0118] Synthesis of M1-3:

[0119] Compound M1-2 (566 g, 1.75 mol) and 4 L of hexafluoroisopropanol were added to a 10 L three-necked flask, the system was cooled to below 0 °C, and trifluoromethanesulfonic acid solution (24 ml, 0.28 mol) was slowly added dropwise. The temperature of the system was controlled below 0 °C during the addition process. After the addition was completed, the reaction solution was warmed to room temperature and the reaction was continued for 2 h until the reaction was completed. After the reaction was completed, 50 ml of ice water was added for quenching, and most of the hexafluoroisopropanol solvent was removed by low temperature concentration. Then 2000 ml of saturated sodium bicarbonate solution was added and stirred for 20 min, and then 2 L of ethyl acetate was used for extraction each time, and the extraction was performed 3 times. The organic phases were combined, dried over anhydrous sodium sulfate, concentrated, and recrystallized from ethyl acetate / petroleum ether to obtain compound M1-3 (493 g, yield 90%), HPLC content 99%, LC-MS showed a molecular weight of 313.06.

[0120] Synthesis of M1-4:

[0121] Under an inert atmosphere, 4-bromo-2-chlorophenanthrene (493 g, 1.0 mol) and 5000 ml of THF were added to a 10 L three-necked flask, stirred, and the system was cooled to below -70 ° C. A 2.0 mol / L LDA THF solution (888 ml, 1.77 mol) was added dropwise to the above system, and stirred at -70 ° C for 1 hour. DMF (197 ml, 2.54 mol) solution was slowly added dropwise to the above reaction system, keeping the internal temperature below -70 ° C, and the reaction was continued at -70 ° C for 1 hour. The temperature was slowly raised to -30 ° C, and the reactant was poured into a 1M HCl (10 L) solution and stirred for 1 hour. The reaction was concentrated at low temperature to remove most of the THF, and then extracted with 2 L of dichloromethane each time, extracted 3 times, combined the organic layers, dried over anhydrous Na2SO4, and concentrated in vacuo to obtain compound M1-4 (324 g, yield 60%), and LC-MS showed a molecular weight of 320.91.

[0122] Synthesis of M1-5:

[0123] Under an inert atmosphere, M1-4 (320 g, 1.0 mol), phenylboronic acid (122 g, 1.0 mol), potassium phosphate (425 g, 2.0 mol), 1,4-dioxane 2000 mL, deionized water 500 mL, Pd(PPh3)4 (11.6 g, 0.01 mol) were added to a 5L three-necked flask, the system was heated to reflux, and the reaction was continued for 18 hours until the reaction was completed. The reaction solution was first washed with water and separated, the organic phase was passed through a diatomaceous earth funnel and the filtrate was collected, and the solid crude product was obtained by vacuum concentration, and an appropriate proportion of ethyl acetate / petroleum ether solution 1000 mL was added, the mixture was dispersed and slurried, and the compound M1-5 was obtained by filtration, which was 231 g, with a yield of 73%, an HPLC content of 99%, and a molecular weight of 317.11 according to LC-MS.

[0124] Synthesis of M1-6:

[0125] Under an inert atmosphere, compound M1-5 (231 g, 0.73 mol), (methoxymethyl) triphenylphosphonium chloride (250 g, 0.73 mol), and 2000 ml of THF were added to a 5L three-necked flask, and the temperature was lowered to below 0°C. 800 ml of a THF solution of lithium bis(trimethylsilyl)amide (147 g, 0.876 mol) was slowly added, and the reaction was continued at 0°C for 1 h until the reaction was completed. After the reaction was completed, 50 ml of ice water was added for quenching, and most of the THF was removed by low temperature concentration. Then, 1000 ml of a saturated sodium bisulfate solution was added and stirred for 20 min, and then extracted with 1500 ml of ethyl acetate each time for 3 times, and the organic phases were combined, dried over anhydrous sodium sulfate, concentrated, and recrystallized from ethyl acetate / petroleum ether to obtain compound M1-6 (196 g, yield 78%), HPLC content 99%, LC-MS showed a molecular weight of 345.10.

[0126] Synthesis of M1:

[0127] Compound M1-6 (193 g, 0.56 mol) and 2000 ml of hexafluoroisopropanol were added to a 5L three-necked flask, the system was cooled to below 0 °C, and trifluoromethanesulfonic acid solution (7.4 ml, 0.084 mol) was slowly added dropwise. The temperature of the system was controlled below 0 °C during the addition process. After the addition was completed, the reaction solution was warmed to room temperature and the reaction was continued for 2 h until the reaction was completed. After the reaction was completed, 50 ml of ice water was added for quenching, and most of the hexafluoroisopropanol solvent was removed by low temperature concentration. Then 1000 ml of saturated sodium bicarbonate solution was added for pulping, and then 1500 ml of ethyl acetate was used for extraction each time. The organic phases were combined, dried over anhydrous sodium sulfate, concentrated, and recrystallized from ethyl acetate / petroleum ether to obtain 159 g of compound M1, with a yield of 91%, HPLC content of 99%, and LC-MS showing a molecular weight of 313.06.

[0128] 2. Synthesis steps of key intermediate M2:

[0129] ;

[0130] .

[0131] Operation process: Under inert atmosphere, add M1 (71g, 0.2mol), biboric acid pinacol ester (53g, 0.21mol), potassium acetate (39g, 0.4mol), 1,4-dioxane 500mL into a 1L three-necked flask, start stirring and heat to 60~65℃, then add X-Phos (4.8g, 0.01mol), Pd2(dba)3 (3.7g, 0.004mol), and then continue to heat to reflux reaction for 8h until the reaction is completed. The reaction solution is directly filtered, the filtrate is collected, concentrated under reduced pressure to dryness, dissolved in 600mL toluene, and then washed with water. After the organic phase passes through the silica gel column, the column liquid is again concentrated under reduced pressure until solids precipitate and then stopped, cooled to 10~15℃ for crystallization, filtered after crystallization is completed, and M2 is obtained by drying to obtain 65g, with a yield of 80%, HPLC content of 99%, and LC-MS showing a molecular weight of 405.16.

[0132] Compound N1 synthesis steps:

[0133] ;

[0134] .

[0135] Operation process: Under inert atmosphere, 2-(4-bromophenyl)-4,6-diphenyl-1,3,5-triazine (3.9 g, 0.01 mol), M2 (4.0 g, 0.01 mol), 1,4-dioxane 50 mL, potassium phosphate (4.2 g, 0.02 mol), deionized water 10 mL, Pd(PPh3)4 (120 mg, 0.1 mmol) were added to a 100 mL three-necked flask, the system was heated to reflux, and the reaction was continued for 18 h. The reaction was completed. The reaction solution was first washed with water and separated, the organic phase was passed through a diatomaceous earth funnel and the filtrate was collected, and the solid crude product was concentrated under reduced pressure to obtain a solid crude product, and 30 mL of ethyl acetate / petroleum ether solution in an appropriate ratio was added, dispersed and slurried, and filtered to obtain 4.3 g of compound N1, with a yield of 73%, HPLC content of 99%, and LC-MS showing a molecular weight of 586.21.

[0136] Compound N62 synthesis steps:

[0137] .

[0138] Operation process: The synthesis of compound N62 is basically the same as that of compound N1. 2.7 g of 5-chloro-2,3-diphenylpyrazine was added to obtain 3.8 g of compound N62 with a yield of 75%. The HPLC content was 99%, and the LC-MS showed a molecular weight of 509.16.

[0139] Compound N94 synthesis steps:

[0140] .

[0141] Operation process: Under inert atmosphere, M1 (3.6 g, 0.01 mol), 1,8-naphthalimide (2.0 g, 0.01 mol), and 50 mL of toluene were added into a 100 mL three-necked flask, and stirred until the solution was clear. Pd2(dba)3 (183 mg, 0.2 mmol), Am-phos (133 mg, 0.5 mmol), and sodium tert-butoxide (1.9 g, 0.01 mol) were added. The reaction solution was heated to 120 °C and the reaction was continued for 10 h. After the reaction was completed, diatomaceous earth was used for hot filtration. The filtrate was cooled to room temperature and washed with purified water. After separation, the organic phase was retained, and the aqueous phase was extracted with ethyl acetate. The organic phases were combined, dried over anhydrous magnesium sulfate, concentrated, and passed through a column to obtain compound N94, weighing 3.9 g, with a yield of 82%, an HPLC content of 99%, and a molecular weight of 474.12 shown by LC-MS.

[0142] Compound P22 synthesis steps:

[0143] .

[0144] Operation process: The synthesis of compound P22 is basically the same as that of compound N94. 9,10-dihydro-9,9-diphenylacridine (3.3 g, 0.01 mol) was added to obtain 4.8 g of compound P22 with a yield of 79%, HPLC content of 99%, and LC-MS showing a molecular weight of 610.19.

[0145] The synthesis process of the compounds described in the present invention is completed with reference to the synthesis process of the above-mentioned compounds N1 and N94. The ideas of the synthesis routes are similar, and the specific compound purification process needs to be crystallized and purified in combination with the properties of the compound itself or separated and purified by means of a chromatographic column. The list of the main organic structural fragments or intermediate raw materials used in the synthesis process of the above-mentioned preferred compounds P1~P84, N1~N132 is shown in Table 1 below:

[0146] Table 1 List of raw materials for compound synthesis

[0147]

[0148] Figures 2~5 These are the NMR spectra of compound N1, compound N62, compound N94, and compound P22, where the horizontal axis is the chemical shift f1 and the vertical axis is the absorption peak intensity.

[0149] The above-mentioned preferred dibenzo[c,g]phenanthrene derivatives are used for device preparation test application. The above-mentioned compounds P1~P84 have the characteristics of hole transport and can be used as hole transport layer materials. The above-mentioned compounds N1~N132 have the characteristics of electron transport and can be used as electron transport layer materials. However, it is more preferred to use the P-type compound and the N-type compound in the above-mentioned dibenzo[c,g]phenanthrene derivatives as the main light-emitting material by composite co-evaporation.

[0150] Based on the above preferred dibenzo[c,g]phenanthrene derivatives, they are applied to the light-emitting layer in the test device samples. The excellent device performance indicates that the material can be used in a variety of scenarios such as luminous lighting, color imaging (such as mobile phone displays, car displays, tablet computers, TVs, etc.), and handicraft decoration.

[0151] The organic electroluminescent device for testing produced by the present invention is shown in the schematic diagram of the device. Figure 1 As shown, the organic electroluminescent device specifically includes a cathode, an anode and an organic layer located between the cathode and the anode.

[0152] As a preferred embodiment, a substrate layer 01 can be used below the anode layer 02 or above the cathode layer 08. The substrate of the substrate layer 01 is made of glass or polymer material with excellent mechanical strength, thermal stability, waterproofness, and transparency. In addition, a substrate used as a display can also be made with a thin film transistor (TFT) array and a specific display image formed by a combination of transistor arrays.

[0153] As a preferred embodiment, the organic layer includes a hole injection layer 03, a hole transport layer 04, a light-emitting layer 05, an electron transport layer 06, and an electron injection layer 07, wherein the hole transport layer 04 is located between the hole injection layer 03 and the light-emitting layer 05, and the electron transport layer 06 is located between the light-emitting layer 05 and the electron injection layer 07. The main material of the light-emitting layer adopts a composite main structure mode, and is composited by a P-type main light-emitting material and an N-type main light-emitting material, wherein the mass ratio of the P-type main light-emitting material to the N-type main light-emitting material is between 3:7 and 6:4, and a more preferred ratio is 5:5.

[0154] In the device comparison example, the P-type main light-emitting material is selected from any one of the following RH1-1 to RH1-12:

[0155] ;

[0156] ;

[0157] ;

[0158] In the device comparison example, the N-type host light-emitting material is selected from any one of the following RH2-1 to RH2-8:

[0159] ;

[0160] .

[0161] The anode layer 02 can be formed by sputtering or depositing a specific functional layer material on the substrate layer 01, and can be made of transparent conductive oxide materials such as indium tin oxide (ITO), indium zinc oxide (IZO), tin dioxide (SnO2), zinc oxide (ZnO) and any combination thereof. The cathode layer 08 can be made of a metal single substance or alloy with good conductive properties, and preferred metal materials include magnesium (Mg), silver (Ag), aluminum (Al), aluminum-lithium (Al-Li), calcium (Ca), magnesium-indium (Mg-In), magnesium-silver (Mg-Ag) and other metals or alloys and any combination thereof.

[0162] The organic layer can be formed on the electrode by vacuum thermal evaporation, spin coating, inkjet printing and other methods. The compound used as the organic functional layer can be organic small molecules, organic macromolecules and organic polymers, and combinations thereof.

[0163] The hole transport layer 04 can be a hole transport layer (HTL) of a single-layer structure, including a hole transport material mode containing only one compound (a single-layer hole transport layer that has both hole injection function and hole transport effect) and a composite hole transport layer mode containing multiple compounds. The composite hole transport layer is an organic combination of the industry's general arrangement method arranged in the order of hole injection layer (HIL), hole transport layer (HTL), and electron blocking layer (EBL). The light-emitting layer is located between the above-mentioned hole transport layer and the electron transport layer, wherein the P-type main light-emitting material (RH1 type) and the N-type main light-emitting material (RH2 type) are jointly formed into the main light-emitting material required for the device in a mass ratio of 5:5; the preferred dibenzo[c,g]phenanthrene derivatives of the present invention are preferably co-evaporated by composite co-evaporation in a mass ratio of 50:50 to form the main light-emitting material, and the guest light-emitting material is selected from , or One of the above, and the mass ratio of the main luminescent material to the guest luminescent material is preferably 100:0.5. After the preparation of the above main functional layers for realizing organic luminescence is completed, the devices are packaged using the currently common packaging device method in the industry, and the test devices are prepared into 30mm×30mm samples, and then the various luminescent performance indicators of the above samples are tested and detected. Compared with the existing conventional light-emitting devices, the device performance is excellent. Furthermore, using the P-type compound in the above preferred dibenzo[c,g]phenanthrene derivatives as a hole transport layer material, or using the N-type compound as an electron transport layer material, can effectively simplify the device structure and reduce costs.

[0164] Specific preparation process of device embodiment:

[0165] The device application method and specific implementation process of the material are as follows:

[0166] A 30 mm×30 mm×1.0 mm glass substrate with an ITO transparent electrode (anode layer, ITO film thickness is set to 100 nm) is ultrasonically cleaned in a washing liquid, acetone, ultrapure water, and isopropanol in sequence, and the ultrasonic cleaning time for each step is 10 minutes. The cleaned ITO glass substrate is placed in an oven at 80°C for 3 hours, and the baked glass substrate with an ITO transparent electrode is vacuum plasma cleaned for 10 minutes. The above-mentioned glass substrate after plasma treatment is installed on the substrate rack of a vacuum evaporation device, and first vacuum evaporation of F4TCNQ or HATCN, or a mixture of the two, is started on the surface of the side where the ITO transparent electrode is formed to form a hole injection layer 03 (HIL) with a thickness of 10 nm. Then, the compound NPD or FFD or 2-TNATA is evaporated to form a hole transport layer 04 with a film thickness of 90 nm. The main light-emitting layer 05 is continuously evaporated on the hole transport layer. The main light-emitting layer is co-evaporated at a ratio of 100:0.5 between the main light-emitting material and the guest light-emitting material. The main light-emitting material is selected from any one of the above RH1-1 to RH1-12 and any one of RH2-1 to RH2-8. The combination process is compounded at a weight ratio of 5:5 between the two. The guest light-emitting material can be selected from any one of DP-1, DP-2, and DP-3. The thickness of the entire light-emitting layer (EML) is controlled between 30nm and 60nm, preferably 50nm. Then, the electron transport layer 06 (ETL, which can be any one of BPhen, Alq3 or TAZ) is continuously evaporated on the light-emitting layer. The thickness is controlled at 20nm. A 6nm LiQ layer is sputtered and evaporated on the ETL layer to serve as the electron injection layer 07 (EIL) of the device; then a Mg-Ag alloy layer (mass ratio Mg:Ag=1:9) is sputtered and evaporated on the LiQ layer to serve as the cathode layer 08 of the device. The total thickness of the metal layer sputtered and evaporated is controlled at 10nm; before the device is formally packaged, a layer of high-refractive index covering layer material is evaporated, and finally the multilayer structure prepared above is vacuum packaged to isolate air and water vapor, etc., to realize the basic process of device preparation for evaluation.

[0167] The functional layer material structure used in the test device preparation process is introduced as follows

[0168] .

[0169] Preparation scheme of device comparative examples 1 to 4:

[0170] Comparative Example 1: F4TCNQ (10nm) / NPD (90nm) / RH1-3:RH2-2:DP-1=50:50:0.5 (50nm) / Bphen (20nm) / LiQ (6nm) / Mg: Ag=1: 9 (10nm);

[0171] Comparative Example 2: F4TCNQ (10nm) / NPD (90nm) / RH1-3: RH2-6:DP-1=50:50:0.5 (50nm) / Bphen (20nm) / LiQ (6nm) / Mg: Ag=1: 9 (10nm);

[0172] Comparative Example 3: F4TCNQ (10nm) / FFD (90nm) / RH1-4: RH2-2: DP-1 = 50:50:0.5 (50nm) / Alq3 (20nm) / LiQ (6nm) / Mg: Ag = 1: 9 (10nm);

[0173] Comparative Example 4: F4TCNQ (10nm) / 2-TNATA (90nm) / RH1-4: RH2-6:DP-1=50:50:0.5(50nm) / TAZ (20nm) / LiQ(6nm) / Mg:Ag=1:9(10nm);

[0174] Embodiments of the present invention:

[0175] Embodiment 1: The preparation process of Examples 1 to 10 is basically the same as that of Comparative Example 1, except that the preferred compound P9 of the present invention is used to replace RH1-3 as the P-type main light-emitting material, and the preferred compounds N5, N14, N34, N49, N66, N90, N95, N115, N120, and N132 of the present invention are used to replace RH2-2 in sequence as the N-type main light-emitting material, and the other functional layer materials remain unchanged, thereby preparing the devices of Examples 1 to 10.

[0176] Implementation Option 2: The preparation process of Examples 11 to 16 is basically the same as that of Comparative Example 1, except that the preferred compounds P21 and P72 of the present invention are used to replace RH1-3 as the P-type main light-emitting material, and the preferred compounds N34, N66, and N95 of the present invention are used to replace RH2-2 in sequence as the N-type main light-emitting material, and the other functional layer materials remain unchanged, thereby preparing the devices of Examples 11 to 16.

[0177] Implementation scheme three: The light-emitting layer materials of Examples 17 to 19 are consistent with those of Examples 14 to 16, except that the P-type main light-emitting material P72 of Examples 14 to 16 is used as the hole transport layer material, and the N34, N66, and N95 of Examples 14 to 16 are used as the electron transport layer materials in sequence, and the other functional layer materials remain unchanged, thereby preparing the devices of Examples 17 to 19.

[0178] The specific preparation scheme is shown in Table 2.

[0179] Table 2 Structure of each functional layer of the device

[0180]

[0181] The device display performance data was collected for the above comparative example device and the device of the embodiment of the present invention, and the collected data results are shown in Table 3 below:

[0182] Table 3 Device test data

[0183]

[0184] It can be seen from the test data in Table 3 that when the preferred compounds of the present invention are used as the main luminescent material for the test device, the device life and efficiency are improved. In Example 1-16, compared with Comparative Examples 1-2, the devices prepared by compounds N34, N66 and N95 as N-type main luminescent materials have more comprehensive advantages in terms of device performance such as current efficiency and service life than the devices prepared by the N-type main luminescent material of the comparative example. This may be due to the fact that there are more tert-butyl substituents in the molecular structures of the three compounds N34, N66 and N95. The tert-butyl substituent belongs to a large volume substituent, which increases the space demand of the molecule and inhibits the aggregation of molecules, thereby successfully controlling the energy loss of Detex, reducing the roll-off efficiency of the device, and improving the comprehensive luminescent performance of the device. In Example 17-19, compared with Comparative Examples 1-4, the driving voltage is reduced by about 10%, the current efficiency is increased by about 40%, and the service life is extended by about 40%, which shows that the dibenzo[c,g]phenanthrene derivatives disclosed in the present invention realize the integration of device main luminescence, hole transmission, and electron transmission, and can effectively simplify the device structure and reduce costs.

[0185] It can be seen that the preferred compounds of the present invention can be used for multiple purposes when applied to light-emitting devices. In the application process of test practice, such compounds are used in the light-emitting layer of the device, and can also be used in the hole transport layer or electron transport layer of the device, which has a good effect on comprehensively improving the performance of the device and has important commercial value for promotion and application.

[0186] The preferred compounds provided by the present invention have a simple synthesis and preparation process, and the raw materials are readily available, so that the large-scale and sustainable production of products can be easily achieved.

[0187] The above is a detailed introduction to the specific implementation of the preferred compounds of the present invention, but the present invention is not limited to the above implementation; within the scope of common knowledge possessed by those skilled in the art, various local structural adjustment changes can also be made without departing from the purpose of the present invention. The present invention is not limited to the implementation of the above specific embodiments, and it should be understood that the above local adjustment changes should also fall within the scope of the claims of the present invention.

Claims

1. A dibenzo[c,g]phenanthrene derivative, characterized in that: The dibenzo[c,g]phenanthrene derivatives include P-type compounds or N-type compounds; The P-type compound is selected from any one of compounds P1-P37 and compounds P71-P76, and the N-type compound is selected from any one of compounds N67-N78, compounds N91-N118, and compounds N131-N132. The specific structural formula is as follows:

2. An organic electroluminescent device, characterized in that: The invention comprises a cathode, an anode and an organic layer located between the cathode and the anode, wherein the organic layer comprises a hole transport layer, a light-emitting layer and an electron transport layer, and a P-type compound and an N-type compound are co-evaporated as the main light-emitting material of the light-emitting layer in the organic electroluminescent device, the P-type compound is selected from any one or more of compounds P1 to P37 and compounds P71 to P76 in a dibenzo[c,g]phenanthrene derivative as described in claim 1, and the N-type compound is selected from any one or more of compounds N67 to N78, compounds N91 to N118 and compounds N131 to N132 in a dibenzo[c,g]phenanthrene derivative as described in claim 1.

3. An organic electroluminescent device according to claim 2, characterized in that: The material of the hole transport layer is selected from any one of compounds P1-P37 and compounds P71-P76.

4. The organic electroluminescent device according to claim 2, characterized in that: The material of the electron transport layer is selected from any one of compounds N67-N78, compounds N91-N118, and compounds N131-N132.

5. The organic electroluminescent device according to claim 2, characterized in that: The light-emitting layer includes a host light-emitting material and a guest light-emitting material, and the mass ratio of the host light-emitting material to the guest light-emitting material is 100:0.1~1, the host light-emitting material includes a P-type host light-emitting material and an N-type host light-emitting material, the P-type host light-emitting material is selected from any one of compounds P1~P37 and compounds P71~P76, the N-type host light-emitting material is selected from any one of compounds N67~N78, compounds N91~N118, and compounds N131~N132, and the mass ratio of the P-type host light-emitting material to the N-type host light-emitting material is 40:60~30:

70.

6. The organic electroluminescent device according to claim 5, characterized in that: The guest luminescent material is selected from

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