Host material, preparation method therefor and dual-host organic electroluminescent material comprising same, and organic electroluminescent device

Abstract

The present invention belongs to the field of organic electroluminescent materials. Disclosed are a host material, a preparation method therefor and an organic electroluminescent material comprising same, and an organic electroluminescent device. The structure of the host material is represented by chemical formula I. After being used in an organic electroluminescent device, the host material provided by the present invention can not only prolong the service life of the device, but can also reduce the driving voltage and improve the luminous efficiency of the device.

Description

A host material, a preparation method, and a dual-host organic electroluminescent material and an organic electroluminescent device comprising the host material. Technical Field

[0001] This invention belongs to the field of organic electroluminescent materials, specifically relating to a host material, a preparation method, a dual-host organic electroluminescent material containing the host material, and an organic electroluminescent device. Background Technology

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

[0003] OLED light emission occurs through two main methods: fluorescence and phosphorescence. The rapid decay of OLED luminescent materials has become a key factor affecting display quality and lifespan. Deuterium is non-toxic, non-radioactive, and safe for humans. Crucially, its Cd bond is 6-9 times more stable than its CH bond. Introducing deuterium atoms into a material enhances the spin-orbit coupling of the luminescent molecules, thus promoting phosphorescence. However, the shorter bond length and higher bond energy of the carbon-deuterium bond after deuterium introduction lower the energy of the luminescent material. The impact on the luminous efficiency and driving voltage of the device depends on various factors, making the results unpredictable.

[0004] It is known that deuteration of OLED materials can improve the lifespan of OLED devices, but how to improve the driving voltage and luminous efficiency of the devices through deuteration is a technical problem that urgently needs to be solved. Summary of the Invention

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

[0006] It should be noted that the main material disclosed in this invention is obtained through... Substituting D at positions 5, 6, 11, and 12 on the compound makes the compound structure more symmetrical. Adjusting the intermolecular distance and bond energy of the resulting compound helps to improve luminescence efficiency and reduce driving voltage.

[0007] To achieve the above objectives, the first objective of this invention is to provide a main material. The following technical solution is adopted:

[0008] A host material, the structure of which is shown in chemical formula I:

[0009] wherein,

[0010] Ar1 is selected from the group consisting of the following groups which are substituted or unsubstituted by deuterium:

[0011] phenyl, naphthyl, biphenyl, terphenyl, phenylnaphthyl, methylphenyl, dimethylfluorenyl.

[0012] Further, the host material has the following structure:

[0013] In the above technical solution, the host material is selected from any one of the following compounds:

[0014] A second object of the present application is to provide a preparation method of the host material as described above.

[0015] The compound of the present application can be prepared by a synthetic method known to those skilled in the art, or preferably by the following reaction scheme.

[0016] In the above formula, Ar1 is as defined in the above Chemical Formula I, and Hal is selected from Cl and Br.

[0017] Specifically, the preparation method is as follows:

[0018] (1) The reactant I-a (1.0 eq), silver carbonate (0.1-0.3 eq), cyclohexyldiphenylphosphine (0.5-1.0 eq), potassium carbonate (1.0-1.4 eq), deuterium water (T2O) (20-30 eq), and toluene are stirred at 100-120°C for 7-10 hours, then cooled to room temperature, a saturated aqueous ammonia chloride solution is added to terminate the reaction, water and dichloromethane are added, the layers are separated, the organic layer is dried with Na2SO4, filtered, the filtrate is concentrated, isopropyl alcohol is added, and the obtained solid is subjected to column chromatography to obtain the intermediate I-b;

[0019] (2) Ib (1.0 eq), reactant Ic (1.0-1.5 eq), and potassium acetate (2.0-2.5 eq) were added to the reactor and purged with nitrogen three times. 1,4-dioxane was added as solvent and purged with nitrogen three times. Pd2(dba)3 (0.01-0.05 eq) and X-phos (0.05-1.2 eq) were added and purged with nitrogen three times. The mixture was heated under nitrogen protection and refluxed 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 Id.

[0020] (3) Intermediate Id (1.0 eq), reactant Ie (1-1.3 eq), and K2CO3 (2-4 eq) were added to the reactor and purged with nitrogen three times. A mixture of H2O and THF was added as a solvent and purged with nitrogen three times. Then, Pd(Ph3)4 (0.01-0.05 eq) was added and purged with nitrogen three times. The mixture was heated under nitrogen protection and refluxed for 12 hours. After the reaction was completed, the mixture was cooled to room temperature. Then, the solvent was removed under reduced pressure, and the crude product was purified by column chromatography to obtain intermediate If.

[0021] (4) Add intermediate If (1.0 eq), (methoxymethyl)triphenylphosphine chloride (1.0-1.5 eq), 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 and 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 complete, extract the organic layer with dichloromethane and water, dry the extracted organic layer with sodium sulfate, and remove the solvent using a rotary evaporator. Then, purify it by column chromatography to obtain intermediate Ig.

[0022] (5) Under N2 protection, intermediate Ig (1.0 eq), reactant Ih (1-1.3 eq), PdCl2 (dppf) (0.1-0.2 eq) and potassium acetate (2.0-3.0 eq) were dissolved in DMF, heated to 80-90℃, and reacted for 10-12 h. The solvent was removed using a rotary evaporator, and the residue was added to dichloromethane, stirred, filtered, and purified by column chromatography to obtain intermediate Ii.

[0023] (6) Under N2 protection, intermediate I-i (1.0 eq), reactant I-j (1-1.2 eq), palladium acetate (Pd(OAc)2) (0.05-0.15 eq) and 2-cyclohexyl-2,4,6-triisopropyl biphenyl (X-Phos) (0.01-0.3 eq), 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 mixture was heated to 80-95℃ and reacted for 10-12h. The solvent was removed by rotary evaporation, and the remaining material was purified by column chromatography. The filtrate was removed by rotary evaporation to obtain compound I.

[0024] It should be noted that in the series of palladium-catalyzed coupling reactions carried out by the present application, on the one hand, the difference between the activities I>Br>Cl is utilized, and on the other hand, the reaction site is controlled by controlling the reaction conditions, and the reaction is purified by column chromatography or silica gel funnel to remove by-products to obtain the target compound.

[0025] For reference, the following is known:

[0026] Transition Metal Organometallic Chemistry (6th edition), Robert H. Crabtree, Publisher: Shanghai East China University of Technology Press, Publication Time: 2017-09-00, ISBN: 978-7-5628-5111-0, page 388.

[0027] Organic Chemistry and Optoelectronic Material Experiment Tutorial, Chen Runfeng, Publisher: Southeast University Press, Publication Time: 2019-11-00, ISBN: 9787564184230, page 174.

[0028] For raw materials not disclosed, those skilled in the art can use classical Suzuki coupling reaction, Buchwald-Hartwig coupling reaction synthesis, butyllithium reaction, and apply it to the present application.

[0029] In addition, the present application The substitution position of the present application is defined as follows:

[0030] A third object of the present application is to provide a dual-host organic electroluminescent material, which comprises a first host material and a second host material, the first host material being a host material as described above, having a structure shown in formula I; and the second host material having a structure shown in formula II:

[0031] wherein f, n are selected from 0 or 1, and f+n=1;

[0032] Ar1and Ar2are independently selected from the group consisting of:

[0033] Ar3-Ar6are independently selected from the group consisting of hydrogen, substituted or unsubstituted:

[0034] phenyl, naphthalene, anthracene, phenanthrene, biphenyl, terphenyl, quaterphenyl, dimethylfluorene, diphenylfluorene, pyridine, dibenzofuran, dibenzothiophene, 9-phenyl-carbazole, quinoline, benzonaphthofuran, benzonaphthothiophene, quinoxaline, quinazoline, and the group consisting of:

[0035] When substituted, the substituent is selected from D, F or phenyl;

[0036] When substituted by phenyl, the phenyl can be fused with the adjacent group to form a ring.

[0037] In the technical scheme of the present application, the second host material can be specifically illustrated by the following compounds, but is not limited thereto:

[0038] A fourth object of the present application is to provide an organic electroluminescent device comprising the host material or the double-host organic electroluminescent material.

[0039] Specifically, the organic electroluminescent device comprises a first electrode, a second electrode, and at least one layer of organic electroluminescent material arranged between the first electrode and the second electrode; the organic electroluminescent material layer comprises the double-host organic electroluminescent material as described above.

[0040] Further, the double-host organic electroluminescent material serves as a light-emitting layer host material of an organic electroluminescent device.

[0041] Further, 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 double-host organic electroluminescent material to the dopant material is (1-99):(99-1).

[0042] In the present invention, the organic electroluminescent device includes an anode, a hole transport region, a light emitting layer, an electron transport region, and a cathode.

[0043] The anode material is preferably a material having a large work function to smoothly inject holes into the organic material layer, and includes a metal such as vanadium, chromium, copper, zinc, and gold, or an alloy thereof; a metal oxide such as zinc oxide, indium oxide, indium tin oxide (ITO), and indium zinc oxide (IZO); a combination of a metal and an oxide such as ZnO:Al or SnO2:Sb; a conductive polymer such as poly(3-methylthiophene), poly[3,4-(ethylen-1,2-dioxy)thiophene] (PEDOT), polypyrrole, and polyaniline, but is not limited thereto.

[0044] The cathode material is preferably a material having a small work function to smoothly inject electrons into the organic material layer, and includes a metal such as magnesium, calcium, sodium, potassium, titanium, indium, yttrium, lithium, gadolinium, aluminum, silver, tin, and lead, or an alloy thereof; a multi-layered structure material such as LiF / Al or LiO2 / Al; but is not limited thereto.

[0045] 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.

[0046] 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, arylamine-based organic material, hexacenehexaazatriphenylene-based organic material, quinacridone-based organic material, perylene-based organic material, anthraquinone, and polyaniline-based and polythiophene-based conductive polymers.

[0047] 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 a high hole mobility. The hole transport layer material includes arylamine-based organic material, conductive polymer, block copolymer having both a conjugated portion and a non-conjugated portion, but is not limited thereto.

[0048] The electron blocking layer is disposed between the hole transport layer and the light emitting layer, and the electron blocking layer material includes arylamine-based organic material.

[0049] The hole blocking layer is disposed between the hole transport layer and the light emitting layer, and the hole blocking layer material includes triazine-based compound.

[0050] The electron transport region includes an electron transport layer and an electron injection layer.

[0051] The electron transport layer promotes electron transport. Electron transport materials are materials with high electron mobility that receive electrons from the cathode and transport them to the light-emitting layer. Electron transport materials include, but are not limited to, Al complexes of 8-hydroxyquinoline, Alq3 complexes, organic free radical compounds, and hydroxyflavonoid-metal complexes. The thickness of the electron transport layer ranges from 1 nm to 50 nm, preventing a decrease in electron transport properties and an increase in driving voltage.

[0052] The electron injection layer promotes electron injection. Electron injection materials are those capable of transporting electrons, exhibiting excellent electron injection effects on the luminescent layer or luminescent material, preventing excitons generated in the luminescent layer from migrating to the hole injection layer, and possessing excellent thin-film formation capabilities. Electron injection layer materials include fluorenones, anthraquinone dimethane, biphenylquinone, thiamethane dioxide, azoles, diazoles, triazoles, imidazoles, perylenetetracarboxylic acid, fluorenemethane, anthrones, and their derivatives, metal complexes, and nitrogen-containing five-membered ring derivatives, but are not limited to these.

[0053] In this invention, the organic electroluminescent device can be a top-emitting type, a bottom-emitting type, or a dual-sided emitting type.

[0054] The devices described in this invention can be used in organic light-emitting devices, including but not limited to flat panel displays, computer monitors, a medical monitor, a television set, billboards, a lamp for internal or external lighting and / or signaling, head-up displays, fully transparent or partially transparent displays, flexible displays, a laser printer, a telephone, a mobile phone, tablets, a photo album, a personal digital assistant (PDA), a wearable device, a laptop computer, a digital camera, a camcorder, a viewfinder, a microdisplay, a 3D display, a virtual reality or augmented reality display, vehicles, video walls comprising multiple displays tiled together, theater or stadium screens, phototherapy devices, and signs.

[0055] Compared with the prior art, the present invention provides a host material, a preparation method, a dual-host organic electroluminescent material containing the host material, and an organic electroluminescent device, which have the following superior effects:

[0056] 1) This invention provides a main material, through... By introducing deuterium (D) atomic groups at specific positions on the ring, Formula I was obtained as the host material; specifically, in Substituting D at positions 5, 6, 11, and 12 on the compound makes the compound structure more symmetrical. Adjusting the intermolecular distance and bond energy of the resulting compound helps to improve luminescence efficiency and reduce driving voltage.

[0057] 2) This invention provides a dual-host organic electroluminescent material, which is composed of a first host material and a second host material. The first host material is selected from the compound shown in Formula I, and the second host material is selected from the compound shown in Formula II. When used in organic electroluminescent devices, it can not only extend the life of the device, but also reduce the driving voltage and improve the luminous efficiency of the device. Attached Figure Description

[0058] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on the provided drawings without creative effort.

[0059] Figure 1 is the proton NMR spectrum of compound I-1 provided in Example 1 of this invention. Detailed Implementation

[0060] The technical solution of the present invention will be clearly and completely described below with reference to the embodiments and related drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present invention.

[0061] This invention specifically discloses a host material, a preparation method, and a dual-host organic electroluminescent material and an organic electroluminescent device containing the host material.

[0062] It should be noted that the values ​​given in the following embodiments are as accurate as possible. However, those skilled in the art will understand that due to unavoidable measurement errors and experimental operation issues, each number should be understood as an approximation rather than an absolutely accurate value.

[0063] The features and performance of the present invention will be further described in detail below with reference to specific embodiments.

[0064] Example 1: Synthesis of Compound I-1

[0065] CAS: Reactant 1-a: 321939-67-7; CAS: Reactant 1-e: 59151-16-5; CAS: Reactant 1-j: 1883265-32-4

[0066] (1) Reactants 1-a (1.0 eq), silver carbonate (0.24 eq), cyclohexyldiphenylphosphine (0.61 eq), potassium carbonate (1.2 eq), deuterium water (T2O) (24 eq), and toluene were stirred at 120 °C for 7 hours, and then cooled to room temperature. The reaction was terminated by adding saturated ammonium chloride solution, followed by the addition of water and dichloromethane. The mixture was allowed to separate into layers, and the organic layer was dried with Na2SO4, filtered, and the filtrate was concentrated. Isopropanol was added, and the resulting solid was subjected to column chromatography to obtain intermediate 1-b (yield 48.3%).

[0067] (2) 1-b (1.0 eq), reactant 1-c (1.5 eq), and potassium acetate (2.0 eq) were added to the reactor and purged with nitrogen three times. 1,4-dioxane was added as solvent and purged with nitrogen three times. Pd2(dba)3 (0.01 eq) and X-phos (0.08 eq) were added and purged with nitrogen three times. The mixture was heated under nitrogen protection and refluxed 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%).

[0068] (3) Intermediate 1-d (1.0 eq), reactant 1-e (1.0 eq), and K2CO3 (2 eq) were added to the reactor and purged with nitrogen three times. A mixture of H2O and THF was added as a solvent and purged with nitrogen three times. Pd(Ph3)4 (0.01 eq) was added and purged with nitrogen three times. The mixture was heated under nitrogen protection and refluxed for 12 hours. After the reaction was completed, the mixture was cooled to room temperature. Then, the solvent was removed under reduced pressure, and the crude product was purified by column chromatography to obtain intermediate 1-f (yield of 87.7%).

[0069] (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 increased. After stirring at room temperature for 3 hours, distilled water was added, and the organic layer was extracted with ethyl acetate and dried with 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 dried with sodium sulfate. The solvent was removed by rotary evaporator, and then purified by column chromatography to obtain intermediate 1-g (yield 36.2%).

[0070] (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 using a rotary evaporator, and the residue was added to dichloromethane, stirred, filtered, and purified by column chromatography to obtain intermediate 1-i (yield 76.5%).

[0071] (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. The mixture was heated to 90 °C and reacted for 12 h. The solvent was removed using a rotary evaporator, and the remaining substances were purified by column chromatography. The filtrate was then purified by a rotary evaporator to obtain compound I-1 (yield 72.8%).

[0072] Figure 1: NMR of compound I-1:

[0073] Mass spectrometry measured value MS (ESI, m / Z): [M+H]+ = 553.61

[0074] HPLC purity: >99%.

[0075] Example 2: Synthesis of Compound I-95

[0076] CAS: Reactant 95-a: 870822-84-7; CAS: Reactant 95-j: 2391956-00-4

[0077] (1) Reactants 95-a (1.0 eq), silver carbonate (0.24 eq), cyclohexyldiphenylphosphine (0.61 eq), potassium carbonate (1.2 eq), deuterium water (T2O) (24 eq) and toluene were stirred at 120 °C for 7 hours, then cooled to room temperature, and the reaction was terminated by adding saturated ammonium chloride aqueous solution. Water and dichloromethane were added, the layers were separated, the organic layer was dried with Na2SO4, filtered, the filtrate was concentrated, isopropanol was added, and the obtained solid was subjected to column chromatography to obtain intermediate 95-b (yield 41.6%).

[0078] (2) 95-b (1.0 eq), reactant 95-c (1.5 eq), and potassium acetate (2.0 eq) were added to the reactor and purged with nitrogen three times. 1,4-dioxane was added as solvent and purged with nitrogen three times. Pd2(dba)3 (0.01 eq) and X-phos (0.08 eq) were added and purged with nitrogen three times. The mixture was heated under nitrogen protection and refluxed 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%).

[0079] (3) Intermediate 95-d (1.0 eq), reactant 95-e (1.0 eq), and K2CO3 (2 eq) were added to the reactor and purged with nitrogen three times. A mixture of H2O and THF was added as a solvent and purged with nitrogen three times. Pd(Ph3)4 (0.01 eq) was added and purged with nitrogen three times. The mixture was heated under nitrogen protection and refluxed for 12 hours. After the reaction was completed, the mixture was cooled to room temperature. Then, the solvent was removed under reduced pressure, and the crude product was purified by column chromatography to obtain intermediate 95-f (yield of 83.6%).

[0080] (4) Intermediate 95-f (1.0 eq), (methoxymethyl)triphenylphosphine chloride (1.3 eq) and THF were added to the 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. The organic layer was extracted with ethyl acetate and the organic phase was dried with sodium sulfate without further purification. Boron trifluoride ether 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 rotary evaporator. Subsequently, it was purified by column chromatography to obtain intermediate 95-g (yield 29.5%).

[0081] (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, heated to 90 °C, and reacted for 12 h. The solvent was removed using a rotary evaporator, and the residue was added to dichloromethane, stirred, filtered, and purified by column chromatography to obtain intermediate 95-i (yield 71.8%).

[0082] (6) Under N2 protection, intermediate 95-i (1.0 eq), reactant 95-j (1.2 eq), palladium acetate (Pd(OAc)2) (0.15 eq), 2-cyclohexyl-2,4,6-triisopropylbiphenyl (X-Phos) (0.01-0.053 eq), and cesium carbonate (Cs2CO3) (2.2 eq) were added to a mixed solvent of toluene, ethanol, and water (4:1:1), respectively. The mixture was heated to 90 °C and reacted for 12 h. The solvent was removed using a rotary evaporator, and the remaining substances were purified by column chromatography. The filtrate was then purified by a rotary evaporator to obtain compound I-95 (yield 76.3%).

[0083] Mass spectrometry measured value MS (ESI, m / Z): [M+H]+ = 558.68

[0084] HPLC purity: >99%.

[0085] The following compounds were synthesized using the method described in the embodiments of this application, and their molecular formulas and mass spectra are shown in Table 1 below. The mass spectrometer used in this application was a Waters XEVO TQD, a low-precision mass spectrometer with an ESI source.

[0086] Table 1 Molecular formulas and mass spectra

[0087] In addition, it should be noted that other compounds in this application can be obtained by referring to the methods of the embodiments listed above, so they will not be listed one by one here.

[0088] Device Example 1

[0089] 1) Substrate processing:

[0090] Select ITO / Ag / ITO glass with anodized surface as substrate. First, use stripping solution to remove the protective film on the substrate surface. Then, use deionized water to perform ultrasonic and spray processes on the substrate after film removal. Finally, bake the substrate.

[0091] 2) Evaporation process:

[0092] ① After cleaning, a glass substrate is selected, and a hole injection material HI-01 is deposited on the substrate with an anode using vacuum evaporation to form a thickness of [thickness missing]. The hole injection layer is composed of HT-01 and HI-01 co-evaporated, with HI-01 doping ratio of 3%.

[0093] ② Hole transport material HT-01 is deposited on the hole injection layer by vacuum evaporation to form a thickness The hole transport layer.

[0094] ③ The first luminescent host material compound I-1 and the second luminescent host material compound LA-009 (Formula I:Formula II = 1:1) and the dopant material RD-01 are mixed and deposited on the hole transport layer by vacuum evaporation at a mass ratio of 97:3 to form a layer with a thickness of The luminescent layer.

[0095] ④ A hole blocking layer material HB-01 is deposited on the light-emitting layer by vacuum evaporation to form a thickness of Hole-blocking layer.

[0096] ⑤ Electron transport materials ET-01 and Liq are mixed and deposited in a 50:50 mass ratio on the hole blocking layer by vacuum evaporation to form a layer with a thickness of [missing information]. The electron transport layer.

[0097] ⑥ Electron injection material YB is deposited on the electron transport layer by vacuum evaporation to form a layer with a thickness of [missing information]. The electron injection layer.

[0098] ⑦ A cathode material Mg:Ag (1:9) is deposited on the electron injection layer by vacuum evaporation to form a layer with a thickness of [missing information]. The cathode.

[0099] ⑧ CP-01 material is deposited on the cathode by vacuum evaporation to form a thickness of [missing information]. By extracting the light from the layer, a light-emitting device can be obtained.

[0100] The materials involved are as follows:

[0101] Device Examples 2-39

[0102] Organic electroluminescent devices were prepared using the same method as in Device Example 1, except that the host materials of the compounds in Formula I and Formula II were different, as shown in Table 2.

[0103] Comparative Examples 1-23

[0104] Organic electroluminescent devices were prepared using the same method as in Device Example 1, except that the host materials of the compounds in Formula I and Formula II were different, as shown in Table 2.

[0105] The driving voltage, luminous efficiency, and lifetime of the organic electroluminescent devices obtained in Examples 1-39 and Comparative Examples 1-23 were characterized at a brightness of 6000 nits. The test results are shown in Table 2 below.

[0106] Table 2. Results of luminous properties test (luminance value 6000 nits)

[0107] As shown in Table 2, Comparative Examples 1-10 and Device Examples 1-39 are dual-body material devices, while Comparative Examples 11-23 contain only a single body material. Overall, the performance of devices with a single body material is lower than that of devices with dual body materials.

[0108] In devices containing dual host materials, the first host material is selected from comparative compounds 1-10, and the device performance using formula II of the present invention as the second host material is as follows: driving voltage 3.55-3.7V, efficiency 47.5-51.9cd / A; when the first host material is selected from formula I and the second host material is selected from formula II, the device performance is significantly improved, with a driving voltage of 3.19-3.45V, efficiency 56.2-63.5cd / A, and lifetime of 1582-1682h; thus achieving the technical effects of low driving voltage, high efficiency, and long lifetime.

[0109] Formula I differs from comparative compounds 4 and 6 primarily in the deuteration position and the absence of dibenzofuran in the side chain. Formula I of this invention... Substituting D at positions 5, 6, 11, and 12 on the compound makes the structure more symmetrical, adjusting the intermolecular distance and bond energy. In the test results, the lifetimes of comparative compounds 4 and 6 were further improved compared to other comparative compounds. However, due to the deuteration positions of the comparative compounds... Adding bits 5-10 does not improve efficiency or drive voltage performance.

[0110] In Formula I, compound I-1 of the present invention and comparative compounds 9, 9; compound I-7 of the present invention and comparative compound 2; compound I-73 of the present invention and comparative compound 8; and compound I-146 of the present invention and comparative compound 7 are parallel comparative compounds, the difference being that... The substitution of deuterium and the different positions of the deuterium substitutions resulted in a significant improvement in device performance compared to the comparative example.

[0111] The first main material of this invention is selected from the compound shown in Formula I above, and the second main material is selected from Formula II below. When used in organic electroluminescent devices, it not only extends the lifespan of the device, but also reduces the driving voltage and improves the luminous efficiency of the device.

[0112] The above description of the disclosed embodiments enables those skilled in the art to make or use the invention. Various modifications to these embodiments will be readily apparent to those 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 invention. Therefore, the invention is not to be limited to the embodiments shown herein, but is to be accorded 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, whether deuterated or unsubstituted: Phenyl, naphthyl, biphenyl, terphenyl, phenylnaphthyl, methylphenyl, dimethylfluorenyl.

2. The main material according to claim 1, characterized in that, The specific structure of the main material is shown below:

3. The main 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 as described in claim 1, characterized in that, The procedure is as follows: (1) 1.0 eq reactant Ia, 0.1-0.3 eq silver carbonate, 0.5-1.0 eq cyclohexyldiphenylphosphine, 1.0-1.4 eq potassium carbonate, 20-30 eq deuterium water T2O and toluene were stirred at 100-120℃ for 7-10 hours, then cooled to room temperature, and the reaction was terminated by adding saturated ammonium chloride aqueous solution. Water and dichloromethane were added, the layers were separated, the organic layer was dried with Na2SO4, filtered, the filtrate was concentrated, isopropanol was added, and the obtained solid was subjected to column chromatography to obtain intermediate Ib; (2) 1.0 eq intermediate Ib, 1.0-1.5 eq reactant Ic, and 2.0-2.5 eq potassium acetate were added to the reactor and purged with nitrogen three times. 1,4-dioxane was added as solvent and purged with nitrogen three times. Then 0.01-0.05 eq Pd2(dba)3 and 0.05-1.2 eq X-phos were added and purged with nitrogen three times. The mixture was heated under nitrogen protection and refluxed 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 Id. (3) 1.0 eq intermediate Id, 1-1.3 eq reactant Ie, and 2-4 eq K2CO3 were added to the reactor and purged with nitrogen three times. A mixture of H2O and THF was added as a solvent and purged with nitrogen three times. Then, 0.01-0.05 eq Pd(Ph3)4 was added and purged with nitrogen three times. The mixture was heated under nitrogen protection and refluxed for 12 hours. After the reaction was completed, the mixture was cooled to room temperature. Then, the solvent was removed under reduced pressure, and the crude product was purified by column chromatography to obtain intermediate If. (4) Add 1.0 eq intermediate If, ​​1.0-1.5 eq (methoxymethyl)triphenylphosphine chloride and THF to the reaction vessel and stir for 10 minutes. Slowly add potassium tert-butoxide solution dropwise at 0°C, then slowly raise the temperature and stir at room temperature for 3-5 hours. Add distilled water and 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 complete, extract the organic layer with dichloromethane and water, dry the extracted organic layer with sodium sulfate, and remove the solvent with a rotary evaporator. Subsequently, it was purified by column chromatography to obtain intermediate Ig; (5) Under N2 protection, 1.0 eq intermediate Ig, 1-1.3 eq reactant Ih, 0.1-0.2 eq PdCl2 (dppf) and 2.0-3.0 eq potassium acetate were dissolved in DMF, heated to 80-90℃ and reacted for 10-12 h. The solvent was removed using a rotary evaporator. The residue was added to dichloromethane, stirred, filtered, and purified by column chromatography to obtain intermediate Ii. (6) Under N2 protection, 1.0 eq intermediate Ii, 1-1.2 eq reactant Ij, 0.05-0.15 eq palladium acetate Pd(OAc)2 and 0.01-0.3 eq 2-cyclohexyl-2,4,6-triisopropylbiphenyl X-Phos, and 2.0-2.5 eq cesium carbonate Cs2CO3 were added to a mixed solvent of toluene, ethanol and water in a volume ratio of 4:1:

1. The mixture was heated to 80-95℃ and reacted for 10-12 h. The solvent was removed using a rotary evaporator, and the remaining substances were purified by column chromatography. The filtrate was then removed from the solvent using a rotary evaporator to obtain compound I. The specific synthesis 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. The first host material is the host material described in claim 1, having the structure shown in Formula I; the second host material has the structure shown in Formula II. Where 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, including the following: Phenyl, naphthalene, anthracene, phenanthrene, biphenyl, terphenyl, tetraphenyl, dimethylfluorene, diphenylfluorene, pyridine, dibenzofuran, dibenzothiophene, 9-phenyl-carbazole, quinoline, benzonaphthofuran, benzonaphthothiophene, quinoxaline, quinazoline, and the following groups: When substituted, the substituent is selected from D, F, or phenyl; When phenyl is substituted, the phenyl group fuses with the 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 as described in claim 1 or the dual-host organic electroluminescent material as described in claim 5.

9. The organic electroluminescent device according to claim 8, characterized in that, The organic electroluminescent device includes 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 contains the dual-host organic electroluminescent material.

10. The organic electroluminescent device according to claim 9, characterized in that, The dual-host organic electroluminescent material serves as the host material for the light-emitting layer of the organic electroluminescent device.

Images