Host material, preparation method, double-host organic electroluminescent material containing host material, and organic electroluminescent device

Abstract

The invention belongs to the field of organic electroluminescent materials, and discloses a host material, a preparation method, an organic electroluminescent material containing the host material, and an organic electroluminescent device. The structure of the main body material is as shown in a chemical formula I: # imgabs0 #. After the main body material provided by the invention is applied to the organic electroluminescent device, the service life of the device can be prolonged, the driving voltage can be reduced, and the luminous efficiency of the device can be improved.

Description

Technical Field

[0001] The invention belongs to the field of organic electroluminescent materials, and in particular relates to a host material, a preparation method, a dual-host organic electroluminescent material containing the host material, and an organic electroluminescent device. Background Art

[0002] Organic electroluminescent displays (OLEDs) are active light-emitting display devices. Currently, small and medium-sized OLED displays have been widely used in high-end smartphones produced by companies such as Huawei, Xiaomi, and Samsung. Obtaining the best luminous efficiency of devices under low operating voltage conditions is a common demand in the OLED field.

[0003] OLED light emission is divided into two modes: fluorescent light emission and phosphorescent light emission. Due to the fast decay rate of OLED light-emitting materials, they have gradually become the key materials that affect the display effect and service life of OLED. Deuterium is non-toxic, non-radioactive, and safe for the human body. More importantly, the CD bond is more stable than the CH bond (6-9 times). When deuterium atoms are introduced into the material, the spin-orbit coupling of the luminescent molecules will be enhanced, which is conducive to the generation of phosphorescence. After the introduction of deuterium atoms, due to the short bond length and large bond energy of the carbon-deuterium bond, the energy of the light-emitting material will be reduced. The impact on the luminous efficiency and driving voltage of the light-emitting device depends on the action of many factors, and the results are unpredictable.

[0004] It is currently known that deuterium substitution of OLED materials can improve the life of OLED devices, but how to improve the driving voltage and luminous efficiency of the device through deuterium substitution is a technical problem that urgently needs to be solved. Summary of the invention

[0005] In view of this, and in view of the deficiencies in the prior art, the present invention discloses a host material, a preparation method, a dual-host organic electroluminescent material comprising the host material, and an organic electroluminescent device.

[0006] It should be noted that the host material disclosed in the present invention replaces D at positions 5, 6, 11, and 12 on chrysene, and the deuterated position makes the compound structure more symmetrical, adjusts the molecular distance and bond energy of the obtained compound, and helps to improve the luminous efficiency and reduce the driving voltage.

[0007] In order to achieve the above-mentioned purpose, the first purpose of the present invention is to provide a main body material. The following technical scheme is adopted:

[0008] A host material, the structure of the host material is shown in Chemical Formula I:

[0009] ;

[0010] in,

[0011] Ar1 is selected from the following groups which may be substituted by deuterium:

[0012] Phenyl, naphthyl, biphenyl, terphenyl, phenylnaphthyl, methylphenyl, dimethylfluorenyl.

[0013] Furthermore, the structure of the main material is specifically as follows:

[0014] .

[0015] In the above technical solution, the main material is selected from any one of the following compounds:

[0016]

[0017]

[0018]

[0019]

[0020]

[0021]

[0022]

[0023]

[0024] .

[0025] The second object of the present invention is to provide a method for preparing the host material as described above.

[0026] The compounds of the present invention can be prepared by synthetic methods known to those skilled in the art, or preferably by the following reaction schemes.

[0027] ;

[0028] In the above formula, Ar1 is as defined in the above chemical formula I, and Hal is selected from Cl and Br.

[0029] Specifically, the preparation method is as follows:

[0030] (1) reactants Ia (1.0 eq), silver carbonate (0.1-0.3 eq), cyclohexyldiphenylphosphine (0.5-1.0 eq), potassium carbonate (1.0-1.4 eq), deuterated water (T2O) (20-30 eq) and toluene are stirred at 100-120°C for 7-10 hours, then cooled to room temperature, saturated aqueous ammonium chloride solution is added to terminate the reaction, water and dichloromethane are added, the layers are separated, the organic layer is dried over Na2SO4, filtered, the filtrate is concentrated, isopropanol is added, and the resulting solid is subjected to column chromatography to obtain intermediate Ib;

[0031] (2) Ib (1.0 eq), reactant Ic (1.0-1.5 eq), and potassium acetate (2.0-2.5 eq) were added to a reactor and replaced with nitrogen three times. 1,4-dioxane was added as a solvent and replaced with nitrogen three times. Pd2(dba)3 (0.01-0.05 eq) and X-phos (0.05-1.2 eq) were added and replaced with nitrogen three times. The mixture was heated under reflux for 12 hours under nitrogen protection. After the reaction was completed, the mixture was cooled to room temperature, the solvent was removed under reduced pressure, and the crude product was purified by column chromatography to obtain intermediate Id.

[0032] (3) The intermediate Id (1.0 eq), reactant Ie (1-1.3 eq), and K2CO3 (2-4 eq) were added to the reactor and replaced with nitrogen three times. A mixture of H2O and THF was added as a solvent and replaced with nitrogen three times. Pd(Ph3)4 (0.01-0.05 eq) was added and replaced with nitrogen three times. The mixture was heated under reflux for 12 hours under nitrogen protection. After the reaction was completed, the mixture was cooled to room temperature. Subsequently, the solvent was removed under reduced pressure, and the crude product was purified by column chromatography to obtain the intermediate If.

[0033] (4) Add the intermediate If (1.0eq), (methoxymethyl)triphenylphosphonium chloride (1.0-1.5eq) and THF to a reaction vessel and stir for 10 minutes, slowly add potassium tert-butoxide solution dropwise at 0°C, then slowly increase the temperature, stir at room temperature for 3-5 hours, add distilled water, extract the organic layer with ethyl acetate, and dry the organic phase with sodium sulfate without further purification, add boron trifluoride anisole and dichloromethane to the reaction vessel and stir for 3 hours; after the reaction is completed, extract the organic layer with dichloromethane and water, then dry the extracted organic layer with sodium sulfate, and remove the solvent with a rotary evaporator. Thereafter, purify it by column chromatography to obtain the intermediate Ig;

[0034] (5) Under N2 protection, the intermediate Ig (1.0 eq) and the reactant Ih (1-1.3 eq), PdCl2(dppf) (0.1-0.2eq) and potassium acetate (2.0-3.0eq) were dissolved in DMF, the temperature was raised to 80-90°C, the reaction was carried out for 10-12h, the solvent was removed by a rotary evaporator, dichloromethane was added to the residue, stirred, filtered, and the remaining substance was purified by column chromatography to obtain intermediate Ii;

[0035] (6) Under N2 protection, the intermediate Ii (1.0 eq), the reactant Ij (1-1.2 eq), palladium acetate (Pd(OAc)2) (0.05-0.15 eq), 2-cyclohexyl-2,4,6-triisopropylbiphenyl (X-Phos) (0.01-0.3 eq), and cesium carbonate (Cs2CO3) (2.0-2.5 eq) were added to a mixed solvent of toluene, ethanol, and water (4:1:1), respectively, and the temperature was raised to 80-95°C. The reaction was carried out for 10-12 h, and the solvent was removed by a rotary evaporator. The remaining substance was purified by column chromatography, and the filtrate was freed from the solvent by a rotary evaporator to obtain compound I.

[0036] It should be noted that the series of palladium-catalyzed coupling reactions carried out in the present invention utilize the difference in activity I>Br>Cl on the one hand, and control the reaction site by controlling the reaction conditions on the other hand, and purify the reaction by column chromatography or silica gel funnel to remove by-products to obtain the target compound.

[0037] Reference to common knowledge is as follows:

[0038] "Transition Metal Organic Chemistry" (Original Sixth Edition), Robert H. Crabtree, Publisher: Shanghai East China University of Science and Technology Press, Publication Date: 2017-09-00, ISBN: 978-7-5628-5111-0, page 388.

[0039] "Organic Chemistry and Optoelectronic Materials Experimental Tutorial", Chen Runfeng, Publisher: Southeast University Press, Publication Date: 2019-11-00, ISBN: 9787564184230, Page 174.

[0040] For raw materials that are not disclosed, those skilled in the art can use classic Suzuki coupling reaction, Buchwald-Hartwig coupling reaction synthesis, butyl lithium reaction, and apply them to the present invention.

[0041] In addition, the substitution position of chrysene in the present invention is defined as follows:

[0042] .

[0043] The third object of the present invention is to provide a dual-host organic electroluminescent material, wherein the dual-host organic electroluminescent material comprises a first host material and a second host material, wherein the first host material is the host material as described above and has a structure shown in Formula I; and the second host material has a structure shown in Formula II:

[0044] ;

[0045] Wherein, f and n are selected from 0 or 1, and f+n=1;

[0046] Ar1 and Ar2 are independently selected from the following groups:

[0047] ;

[0048] Ar3-Ar6 are independently selected from hydrogen, substituted or unsubstituted groups as follows:

[0049] Phenyl, naphthalene, anthracene, phenanthrene, biphenyl, terphenyl, quaterphenyl, dimethylfluorene, diphenylfluorene, pyridine, dibenzofuran, dibenzothiophene, 9-phenyl-carbazole, quinoline, benzonaphthofuran, benzonaphthothiophene, quinoxaline, quinazoline, and the following radicals:

[0050] ;

[0051] When substituted, the substituent is selected from D, F or phenyl;

[0052] When substituted with a phenyl group, the phenyl group may be fused with an adjacent group to form a ring.

[0053] In the technical solution of the present invention, the second host material can be specifically illustrated by the following compounds, but is not limited thereto:

[0054]

[0055]

[0056]

[0057]

[0058]

[0059]

[0060]

[0061]

[0062]

[0063]

[0064]

[0065]

[0066] .

[0067] A fourth object of the present invention is to provide an organic electroluminescent device, which comprises the host material or the dual-host organic electroluminescent material.

[0068] Specifically, the organic electroluminescent device comprises a first electrode, a second electrode and at least one organic electroluminescent material layer disposed between the first electrode and the second electrode; the organic electroluminescent material layer comprises the dual-host organic electroluminescent material as described above.

[0069] Furthermore, the dual-host organic electroluminescent material is used as a host material of a light-emitting layer of an organic electroluminescent device.

[0070] Furthermore, the first host material has a structure shown in Formula I, the second host material has a structure shown in Formula II, the mass ratio of the first host material to the second host material is (1~10):(10~1), and the mass ratio of the dual host organic electroluminescent material and the doping material is (1~99):(99~1).

[0071] In the present invention, the organic electroluminescent device comprises an anode, a hole transport region, a light emitting layer, an electron transport region and a cathode.

[0072] The anode material preferably has a material with a large work function so that holes can be smoothly injected into the organic material layer. The anode material includes: metals: such as vanadium, chromium, copper, zinc and gold, or their alloys; metal oxides, such as zinc oxide, indium oxide, indium tin oxide (ITO) and indium zinc oxide (IZO); combinations of metals and oxides, such as ZnO:Al or SnO2:Sb; conductive polymers, such as poly(3-methylthiophene), poly[3,4-(ethylene-1,2-dioxy)thiophene] (PEDOT), polypyrrole and polyaniline, but are not limited thereto.

[0073] The cathode material preferably has a material with a small work function so that electrons can be smoothly injected into the organic material layer. The cathode material includes: metals: such as magnesium, calcium, sodium, potassium, titanium, indium, yttrium, lithium, gadolinium, aluminum, silver, tin and lead, or their alloys; multilayer structure materials, such as LiF / Al or LiO2 / Al; but not limited to these.

[0074] The hole transport region includes a hole injection layer, a hole transport layer, an electron blocking layer and a hole blocking layer, and the light emitting layer is located between the electron blocking layer and the hole blocking layer.

[0075] Wherein, the hole injection layer material is a material that receives holes from the anode at a low voltage, and the highest occupied molecular orbital (HOMO) of the hole injection material is preferably between the work function of the anode material and the HOMO of the surrounding organic material layer. The hole injection material includes metal porphyrin, oligothiophene, organic materials based on arylamine, organic materials based on hexanitrile hexaazatriphenylene, organic materials based on quinacridone, organic materials based on perylene, anthraquinone, and conductive polymers based on polyaniline and polythiophene.

[0076] The hole transport layer material is a material that can receive holes from the anode or the hole injection layer and transport the holes to the light-emitting layer and has high hole mobility. The hole transport layer material includes an organic material based on arylamine, a conductive polymer, and a block copolymer having both a conjugated part and a non-conjugated part, but is not limited thereto.

[0077] The electron blocking layer is disposed between the hole transport layer and the light emitting layer, and the electron blocking layer material includes an arylamine-based organic material.

[0078] The hole blocking layer is disposed between the hole transport layer and the light emitting layer, and the hole blocking layer material includes a triazine-based compound.

[0079] The electron transport region includes an electron transport layer and an electron injection layer.

[0080] The electron transport layer has the function of promoting electron transport. The electron transport material is a material with high electron mobility that receives electrons from the cathode and transports the electrons to the light-emitting layer. The electron transport material includes an Al complex of 8-hydroxyquinoline, a complex of Alq3, an organic free radical compound, and a hydroxyflavone-metal complex, but is not limited thereto. The thickness of the electron transport layer is 1 nm to 50 nm, which can prevent the electron transport characteristics from decreasing and prevent the driving voltage from increasing.

[0081] The electron injection layer has the function of promoting electron injection, and the electron injection material is a material that has the ability to transport electrons, has excellent electron injection effect on the light-emitting layer or the light-emitting material, prevents the excitons generated in the light-emitting layer from migrating to the hole injection layer, and has excellent thin film forming ability. The electron injection layer material includes fluorenone, anthraquinone dimethane, diphenoquinone, thiopyran dioxide, azole, diazole, triazole, imidazole, perylene tetracarboxylic acid, fluorenyl methane, anthrone, etc. and their derivatives, metal complexes, nitrogen-containing five-membered ring derivatives, but is not limited thereto.

[0082] In the present invention, the organic electroluminescent device may be a top emission type, a bottom emission type or a double-side emission type.

[0083] The devices described in the present invention can be used in organic light-emitting devices, including but not limited to flat panel displays, computer monitors, a medical monitor, a television, a billboard, a light for interior or exterior lighting and / or signaling, a head-up display, a fully transparent or partially transparent display, a flexible display, a laser printer, a telephone, a mobile phone, a tablet, a photo album, a personal digital assistant (PDA), a wearable device, a laptop computer, a digital camera, a video camera, a viewfinder, a microdisplay, a three-dimensional display, a virtual reality or augmented reality display, a vehicle, a video wall comprising multiple displays tiled together, a theater or venue screen, a light therapy device and a sign.

[0084] Compared with the prior art, the present invention provides a host material, a preparation method, a dual-host organic electroluminescent material and an organic electroluminescent device containing the host material, which have the following excellent effects:

[0085] 1) The present invention provides a host material, by introducing a deuterium (D) atomic group at a specific position on the chrysene ring, formula I is obtained as the host material; specifically, D is substituted at positions 5, 6, 11, and 12 on the chrysene, and the deuterated position makes the compound structure more symmetrical, adjusts the molecular distance and bond energy of the obtained compound, and helps to improve the luminous efficiency and reduce the driving voltage.

[0086] 2) The present invention provides a dual-host organic electroluminescent material, which is composed of a first host material and a second host material, wherein the first host material is selected from the compound represented by the structural formula I, and the second host material is selected from the compound represented by the structural formula II. After being used in an organic electroluminescent device, it can not only extend the life of the device, but also reduce the driving voltage and improve the luminous efficiency of the device. BRIEF DESCRIPTION OF THE DRAWINGS

[0087] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on the provided drawings without paying creative work.

[0088] Figure 1 This is the hydrogen nuclear magnetic resonance spectrum of compound I-1 provided in Example 1 of the present invention. DETAILED DESCRIPTION

[0089] The technical solution of the present invention will be clearly and completely described below in conjunction with the embodiments of the present invention and the related drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0090] The invention specifically discloses a host material, a preparation method, a dual-host organic electroluminescent material containing the host material, and an organic electroluminescent device.

[0091] It should be noted that the numerical values ​​given in the following examples are as accurate as possible, but those skilled in the art understand that due to unavoidable measurement errors and experimental operation problems, each number should be understood as an approximate number rather than an absolutely accurate value.

[0092] The features and performance of the present invention will be further described in detail below with reference to the embodiments.

[0093] Example 1: Synthesis of Compound I-1

[0094] ;

[0095] CAS: Reactant 1-a: 321939-67-7; CAS: Reactant 1-e: 59151-16-5; CAS: Reactant 1-j: 1883265-32-4

[0096] (1) The reactants 1-a (1.0 eq), silver carbonate (0.24 eq), cyclohexyldiphenylphosphine (0.61 eq), potassium carbonate (1.2 eq), deuterated water (T2O) (24 eq) and toluene were stirred at 120°C for 7 hours and then cooled to room temperature. Saturated aqueous ammonium chloride solution was added to terminate the reaction, water and dichloromethane were added, the layers were separated, the organic layer was dried over Na2SO4, filtered, the filtrate was concentrated, isopropanol was added, and the resulting solid was subjected to column chromatography to obtain intermediate 1-b (yield 48.3%).

[0097] (2) 1-b (1.0 eq), reactant 1-c (1.5 eq), and potassium acetate (2.0 eq) were added to a reactor and replaced with nitrogen three times. 1,4-dioxane was added as a solvent and replaced with nitrogen three times. Pd2(dba)3 (0.01 eq) and X-phos (0.08 eq) were added and replaced with nitrogen three times. The mixture was heated to reflux under nitrogen protection for 12 hours. After the reaction was completed, the mixture was cooled to room temperature, the solvent was removed under reduced pressure, and the crude product was purified by column chromatography to obtain intermediate 1-d (yield 83.1%).

[0098] (3) The intermediate 1-d (1.0 eq), reactant 1-e (1.0 eq), and K2CO3 (2 eq) were added to a reactor and replaced with nitrogen three times. A mixture of H2O and THF was added as a solvent and replaced with nitrogen three times. Pd(Ph3)4 (0.01 eq) was then added and replaced with nitrogen three times. The mixture was heated to reflux under nitrogen protection for 12 hours. After the reaction was completed, the mixture was cooled to room temperature. Subsequently, the solvent was removed under reduced pressure, and the crude product was purified by column chromatography to obtain the intermediate 1-f (yield: 87.7%).

[0099] (4) Intermediate 1-f (1.0 eq), (methoxymethyl)triphenylphosphine chloride (1.3 eq) and THF were added to a reaction vessel and stirred for 10 minutes. Potassium tert-butoxide solution was slowly added dropwise at 0°C, and then the temperature was slowly raised. After stirring at room temperature for 3 hours, distilled water was added thereto, and the organic layer was extracted with ethyl acetate and dried over sodium sulfate without further purification. Boron trifluoride anisole and dichloromethane were added to a reaction vessel and stirred for 3 hours. After the reaction was completed, the organic layer was extracted with dichloromethane and water, and then the extracted organic layer was dried over sodium sulfate, and the solvent was removed by a rotary evaporator. Thereafter, it was purified by column chromatography to obtain intermediate 1-g (yield 36.2%).

[0100] (5) Under N2 protection, intermediate 1-g (1.0 eq), reactant 1-h (1.3 eq), PdCl2(dppf) (0.1 eq) and potassium acetate (2.5 eq) were dissolved in DMF, heated to 90 °C, and reacted for 12 h. The solvent was removed by a rotary evaporator, and dichloromethane was added to the residue, stirred, filtered, and the remaining material was purified by column chromatography to obtain intermediate 1-i (yield 76.5%).

[0101] (6) Under N2 protection, intermediate 1-i (1.0 eq), reactant 1-j (1.2 eq), palladium acetate (Pd(OAc)2) (0.15 eq), 2-cyclohexyl-2,4,6-triisopropylbiphenyl (X-Phos) (0.03 eq), and cesium carbonate (Cs2CO3) (2.3 eq) were added to a mixed solvent of toluene, ethanol, and water (4:1:1), respectively, and the temperature was raised to 90°C. The reaction was carried out for 12 h, and the solvent was removed by a rotary evaporator. The remaining substance was purified by column chromatography, and the filtrate was freed from the solvent by a rotary evaporator to obtain compound I-1 (yield 72.8%).

[0102] Figure 1 :NMR of compound I-1:

[0103] Mass spectrometry test value MS (ESI, m / Z): [M+H]+=553.61

[0104] HPLC purity: >99%.

[0105] Example 2: Synthesis of Compound I-95

[0106] ;

[0107] CAS: Reactant 95-a: 870822-84-7; CAS: Reactant 95-j: 2391956-00-4

[0108] (1) Reactants 95-a (1.0 eq), silver carbonate (0.24 eq), cyclohexyldiphenylphosphine (0.61 eq), potassium carbonate (1.2 eq), deuterated water (T2O) (24 eq) and toluene were stirred at 120°C for 7 hours, then cooled to room temperature, saturated aqueous ammonium chloride solution was added to terminate the reaction, water and dichloromethane were added, the layers were separated, the organic layer was dried over Na2SO4, filtered, the filtrate was concentrated, isopropanol was added, and the resulting solid was subjected to column chromatography to obtain intermediate 95-b (yield 41.6%).

[0109] (2) 95-b (1.0 eq), reactant 95-c (1.5 eq), and potassium acetate (2.0 eq) were added to a reactor and replaced with nitrogen three times. 1,4-dioxane was added as a solvent and replaced with nitrogen three times. Pd2(dba)3 (0.01 eq) and X-phos (0.08 eq) were added and replaced with nitrogen three times. The mixture was heated to reflux under nitrogen protection for 12 hours. After the reaction was completed, the mixture was cooled to room temperature, the solvent was removed under reduced pressure, and the crude product was purified by column chromatography to obtain intermediate 95-d (yield 75.4%).

[0110] (3) Intermediate 95-d (1.0 eq), reactant 95-e (1.0 eq), and K2CO3 (2 eq) were added to a reactor and replaced with nitrogen three times. A mixture of H2O and THF was added as a solvent and replaced with nitrogen three times. Pd(Ph3)4 (0.01 eq) was then added and replaced with nitrogen three times. The mixture was heated under reflux for 12 hours under nitrogen protection. After the reaction was completed, the mixture was cooled to room temperature. Subsequently, the solvent was removed under reduced pressure, and the crude product was purified by column chromatography to obtain intermediate 95-f (yield: 83.6%).

[0111] (4) Intermediate 95-f (1.0 eq), (methoxymethyl)triphenylphosphine chloride (1.3 eq) and THF were added to a reaction vessel and stirred for 10 minutes. Potassium tert-butoxide solution was slowly added dropwise at 0°C, and then the temperature was slowly increased. After stirring at room temperature for 3 hours, distilled water was added thereto. The organic layer was extracted with ethyl acetate and dried with sodium sulfate without further purification. Boron trifluoride etherate and dichloromethane were added to the reaction vessel and stirred for 3 hours. After the reaction was completed, the organic layer was extracted with dichloromethane and water, and then the extracted organic layer was dried with sodium sulfate. The solvent was removed by a rotary evaporator, and then it was purified by column chromatography to obtain intermediate 95-g (yield: 29.5%).

[0112] (5) Under N2 protection, intermediate 95-g (1.0 eq), reactant 95-h (1.3 eq), PdCl2(dppf) (0.1 eq) and potassium acetate (2.5 eq) were dissolved in DMF, the temperature was raised to 90°C, and the reaction was carried out for 12 h. The solvent was removed by a rotary evaporator, and dichloromethane was added to the residue, stirred, filtered, and the remaining material was purified by column chromatography to obtain intermediate 95-i (yield 71.8%).

[0113] (6) Under N2 protection, intermediate 95-i (1.0 eq), reactant 95-j (1.2 eq), palladium acetate (Pd(OAc)2) (0.15 eq) and 2-cyclohexyl-2,4,6-triisopropylbiphenyl (X-Phos) (0.01-0.053 eq), cesium carbonate (Cs2CO3) (2.2 eq) were added to a mixed solvent of toluene, ethanol and water (4:1:1), respectively, and the temperature was raised to 90°C. The reaction was carried out for 12 h, and the solvent was removed by a rotary evaporator. The remaining substance was purified by column chromatography, and the filtrate was freed from the solvent by a rotary evaporator to obtain compound I-95 (yield 76.3%).

[0114] Mass spectrometry test value MS (ESI, m / Z): [M+H]+=558.68

[0115] HPLC purity: >99%.

[0116] The following compounds were synthesized by referring to the method of the examples of the present application, and their molecular formulas and mass spectra are shown in Table 1. The mass spectrometer model used in the mass spectrometry test in the present application is Waters XEVO TQD, low precision, ESI source test.

[0117] Table 1 Molecular formula and mass spectrum

[0118]

[0119] In addition, it should be noted that other compounds of the present application can be obtained by referring to the methods of the above-mentioned embodiments, so they will not be listed one by one here.

[0120] Device Example 1

[0121] 1) Substrate processing:

[0122] Select ITO / Ag / ITO glass with an anode on the surface as the substrate, first use a stripping liquid to remove the protective film on the surface of the substrate, then use deionized water to perform ultrasonic and spray processes on the substrate after film removal, and finally perform a baking process on the substrate;

[0123] 2) Evaporation process:

[0124] ① Select a cleaned glass substrate and evaporate the hole injection material HI-01 on the substrate with an anode by vacuum evaporation to form a hole injection layer with a thickness of 100Å, wherein the layer is co-evaporated with HT-01 and HI-01, and the doping ratio of HI-01 is 3%.

[0125] ② The hole transport material HT-01 is evaporated on the hole injection layer by vacuum evaporation to form a hole transport layer with a thickness of 900Å.

[0126] ③ The first light-emitting main material compound I-1 and the second light-emitting main material compound LA-009 (Formula I: Formula II = 1:1) and the doping material RD-01 are mixed and deposited on the hole transport layer in a mass ratio of 97:3 by vacuum evaporation to form a light-emitting layer with a thickness of 400Å.

[0127] ④ Vacuum evaporation is used to deposit the hole blocking layer material HB-01 on the light-emitting layer to form a hole blocking layer with a thickness of 50Å.

[0128] ⑤ Mix and evaporate the electron transport material ET-01 and Liq in a mass ratio of 50:50 on the hole blocking layer by vacuum evaporation to form an electron transport layer with a thickness of 300Å.

[0129] ⑥ The electron injection material YB is evaporated on the electron transport layer by vacuum evaporation to form an electron injection layer with a thickness of 10Å.

[0130] ⑦ The cathode material Mg:Ag (1:9) is evaporated on the electron injection layer by vacuum evaporation to form a cathode with a thickness of 130Å.

[0131] ⑧ CP-01 material is evaporated on the cathode by vacuum evaporation to form a light extraction layer with a thickness of 650Å to obtain a light-emitting device.

[0132] The materials involved are as follows:

[0133] .

[0134] Device Example 2-39

[0135] The organic electroluminescent device was prepared by the same method as in Device Example 1, except that the main materials of the compounds in Formula I and Formula II were different, as shown in Table 2:

[0136] Comparative Example 1-Comparative Example 23

[0137] The organic electroluminescent device was prepared by the same method as in Device Example 1, except that the main materials of the compounds in Formula I and Formula II were different, as shown in Table 2:

[0138]

[0139] .

[0140] The driving voltage, luminous efficiency, and lifespan of the organic electroluminescent devices obtained from the device embodiments 1-39 and the device comparative examples 1-23 were characterized at a brightness of 6000 (nits). The test results are shown in Table 2 below.

[0141] Table 2 Luminous characteristics test results (brightness value is 6000 nits)

[0142]

[0143] According to Table 2, Comparative Examples 1 to 10 and device embodiments 1 to 39 are dual-host material devices, and Comparative Examples 11 to 23 contain only a single host material. Overall, the device performance of a single host material is lower than that of a dual host material.

[0144] In the device containing two main materials at the same time, the first main material layer is selected from the comparison compound 1-10, and the device performance of the present invention formula II as the second main material is 3.55-3.7V driving voltage and 47.5-51.9cd / A efficiency; when the first main material is selected from formula I and the second main material is selected from formula II, the device performance has been greatly improved, the driving voltage is 3.19-3.45V, the efficiency is 56.2-63.5cd / A, and the life is 1582-1682h; the technical effects of low driving voltage, high efficiency and long life are obtained.

[0145] The main difference between Formula I and Comparative Compounds 4 and 6 is that the deuterated positions are different and the side chain does not contain dibenzofuran. Formula I of the present invention replaces D at positions 5, 6, 11, and 12 on chrysene. The deuterated positions make the compound structure more symmetrical and adjust the molecular distance and bond energy of the obtained compound. In the test results, the lifespan of Comparative Compounds 4 and 6 is further improved compared with other Comparative Compounds. However, since the deuterated positions of the Comparative Compounds are positions 5-10 of chrysene, there is no improvement in efficiency and driving voltage performance.

[0146] In Formula I, the present compound I-1 and comparative compounds 9, 9, the present compound I-7 and comparative compound 2, the present compound I-73 and comparative compound 8, the present compound I-146 and comparative compound 7 are parallel comparative compounds, the difference being that deuterium is substituted on chrysene and the deuteration position is different. The device performance obtained by the test is significantly improved compared with the comparative example.

[0147] The first host material of the present invention is selected from the compound represented by the structural formula I, and the second host material is selected from the following formula II. When used in an organic electroluminescent device, it not only prolongs the life of the device, but also reduces the driving voltage and improves the luminous efficiency of the device.

[0148] The above description of the disclosed embodiments enables one skilled in the art to implement or use the present invention. Various modifications to these embodiments will be apparent to one skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention will not be limited to the embodiments shown herein, but rather to the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A main material, characterized in that: The structure of the main material is shown in Chemical Formula I: ； in, Ar1 is selected from the following groups which may be substituted by deuterium: Phenyl, naphthyl, biphenyl, terphenyl, phenylnaphthyl, methylphenyl, dimethylfluorenyl.

2. The main body material according to claim 1, characterized in that The structure of the main material is specifically as follows: 。 3. The main body material according to claim 1 or 2, characterized in that: The structure of the host material includes but is not limited to any one of the following compounds: 。 4. A method for preparing the main material according to claim 1, characterized in that: The method operates as follows: (1) 1.0 eq of reactant Ia, 0.1-0.3 eq of silver carbonate, 0.5-1.0 eq of cyclohexyldiphenylphosphine, 1.0-1.4 eq of potassium carbonate, 20-30 eq of deuterated water T2O and toluene are stirred at 100-120°C for 7-10 hours, then cooled to room temperature, saturated aqueous ammonium chloride solution is added to terminate the reaction, water and dichloromethane are added, the layers are separated, the organic layer is dried over Na2SO4, filtered, the filtrate is concentrated, isopropanol is added, and the resulting solid is subjected to column chromatography to obtain intermediate Ib; (2) 1.0 eq of intermediate Ib, 1.0-1.5 eq of reactant Ic, and 2.0-2.5 eq of potassium acetate were added to a reactor and replaced with nitrogen three times. 1,4-dioxane was added as a solvent and replaced with nitrogen three times. Then, 0.01-0.05 eq of Pd2(dba)3 and 0.05-1.2 eq of X-phos were added and replaced with nitrogen three times. The mixture was heated under reflux for 12 hours under nitrogen protection. After the reaction was completed, the mixture was cooled to room temperature, the solvent was removed under reduced pressure, and the crude product was purified by column chromatography to obtain intermediate Id. (3) 1.0 eq of intermediate Id, 1-1.3 eq of reactant Ie, and 2-4 eq of K2CO3 were added to a reactor and replaced with nitrogen three times. A mixture of H2O and THF was added as a solvent and replaced with nitrogen three times. Then, 0.01-0.05 eq of Pd(Ph3)4 was added and replaced with nitrogen three times. The mixture was heated under reflux for 12 hours under nitrogen protection. After the reaction was completed, the mixture was cooled to room temperature. Subsequently, the solvent was removed under reduced pressure, and the crude product was purified by column chromatography to obtain intermediate If. (4) 1.0 eq of the intermediate If, ​​1.0-1.5 eq of (methoxymethyl)triphenylphosphonium chloride and THF were added to a reaction vessel and stirred for 10 minutes, potassium tert-butoxide solution was slowly added dropwise at 0°C, and then the temperature was slowly increased. After stirring at room temperature for 3-5 hours, distilled water was added thereto, and the organic layer was extracted with ethyl acetate and dried with sodium sulfate in turn without further purification. Boron trifluoride anisole and dichloromethane were added to the reaction vessel and stirred for 3 hours. After the reaction was completed, the organic layer was extracted with dichloromethane and water, and then the extracted organic layer was dried with sodium sulfate, and the solvent was removed by a rotary evaporator; Thereafter, it was purified by column chromatography to obtain intermediate Ig; (5) Under N2 protection, 1.0 eq of intermediate Ig, 1-1.3 eq of reactant Ih, 0.1-0.2 eq of PdCl2 (dppf) and 2.0-3.0 eq of potassium acetate were dissolved in DMF, the temperature was raised to 80-90°C, the reaction was carried out for 10-12 h, the solvent was removed by a rotary evaporator, dichloromethane was added to the residue, stirred, filtered, and the remaining substance was purified by column chromatography to obtain intermediate Ii; (6) Under N2 protection, 1.0 eq of intermediate Ii, 1-1.2 eq of reactant Ij, 0.05-0.15 eq of palladium acetate Pd(OAc)2 and 0.01-0.3 eq of 2-cyclohexyl-2,4,6-triisopropylbiphenyl X-Phos, and 2.0-2.5 eq of cesium carbonate Cs2CO3 were added to a mixed solvent of toluene, ethanol, and water in a volume ratio of 4:1:1, respectively, and the temperature was raised to 80-95°C. The reaction was carried out for 10-12 hours, and the solvent was removed by a rotary evaporator. The remaining substance was purified by column chromatography, and the filtrate was freed of the solvent by a rotary evaporator to obtain compound I; The specific synthetic route is as follows: ； In the above formula, Ar1 is as defined in the above chemical formula I, and Hal is selected from Cl and Br.

5. A dual-host organic electroluminescent material, characterized in that: The dual-host organic electroluminescent material comprises a first host material and a second host material, wherein the first host material is the host material according to claim 1 and has a structure shown in Formula I; and the second host material has a structure shown in Formula II: ； Wherein, f and n are selected from 0 or 1, and f+n=1; Ar1 and Ar2 are independently selected from the following groups: ； Ar3-Ar6 are independently selected from hydrogen, substituted or unsubstituted groups as follows: Phenyl, naphthalene, anthracene, phenanthrene, biphenyl, terphenyl, quaterphenyl, dimethylfluorene, diphenylfluorene, pyridine, dibenzofuran, dibenzothiophene, 9-phenyl-carbazole, quinoline, benzonaphthofuran, benzonaphthothiophene, quinoxaline, quinazoline, and the following radicals: ； When substituted, the substituent is selected from D, F or phenyl; When substituted with a phenyl group, the phenyl group is fused with an adjacent group to form a ring.

6. The dual-host organic electroluminescent material according to claim 5, characterized in that: In the dual-host organic electroluminescent material, the mass ratio of the first host material to the second host material is (1-10):(10-1).

7. The dual-host organic electroluminescent material according to claim 5, characterized in that: The structure of the second host material includes but is not limited to any one of the following compounds: 。 8. An organic electroluminescent device, characterized in that: The organic electroluminescent device comprises the host material according to claim 1 or the dual-host organic electroluminescent material according to claim 5 .

9. The organic electroluminescent device according to claim 8, characterized in that: The organic electroluminescent device comprises a first electrode, a second electrode and at least one organic electroluminescent material layer arranged between the first electrode and the second electrode; the organic electroluminescent material layer comprises the dual-host organic electroluminescent material.

10. The organic electroluminescent device according to claim 9, characterized in that: The dual-host organic electroluminescent material is used as a host material of a light-emitting layer of an organic electroluminescent device.

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