A host compound, a double-host material and an organic electroluminescence device

Abstract

The application provides a kind of host compound, double host material and organic electroluminescence device, and belongs to the technical field of organic photoelectric material, the host compound has the structure shown in formula I, the double host material includes first host compound and second host compound, the first host compound is the host compound with the structure shown in formula I;The second host compound has the structure shown in formula II.The first host compound with the specific structure of the application has faster hole mobility, the second host compound has faster electron mobility, the first host compound and the second host compound of the specific structure are used in the application, the hole and electron mobility can be balanced, so that the double host material can increase exciton in the light-emitting layer, not only can improve the luminous efficiency and service life of device, but also can reduce driving voltage.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of organic optoelectronic materials, and particularly relates to a host compound, a double-host material and an organic electroluminescent device. BACKGROUND

[0002] Since the discovery of organic electroluminescence (OLED) technology, it has developed rapidly in the past few decades due to its unique advantages in the field of display and lighting, such as high contrast resulting from self-luminescence, wide viewing angle, and light weight, flexibility, and other characteristics.

[0003] An organic electroluminescent device is usually composed of a multi-layer structure, which generally includes a substrate, an anode, a hole injection layer (HIL), a hole transport layer (HTL), an emission layer (EML), an electron transport layer (ETL), an electron injection layer (EIL), and a cathode. When a voltage is applied to the anode and the cathode, an electric field is generated between the two electrodes. Under the action of the electric field, electrons from the cathode move to the electroluminescent layer, and holes from the anode also move to the electroluminescent layer. Electrons and holes combine in the electroluminescent layer to form excitons. The excitons in the excited state release energy to the outside, and then the electroluminescent layer emits light. Among them, the host material in the emission layer has a great influence on the performance of the device. The traditional single-host material needs to complete the functions of electron transport and hole transport at the same time. The single-host material is difficult to meet the high performance requirements in terms of efficiency and service life, and the double-host material is thus born.

[0004] However, the energy matching and charge transfer process between different hosts and guests of the double-host light-emitting material are not perfect. In some cases, there may be incomplete energy transfer or accumulation of charges in the host material, which prevents some excitons from being effectively converted into photons, reducing the overall light-emitting efficiency and limiting the further improvement of the light-emitting efficiency and service life of the double-host material.

[0005] The organic electroluminescent double-host material still faces many challenges in current research and application, and more double-host materials are urgently needed to solve the problems existing in the prior art and promote the further development of OLED technology in the field of display and lighting. SUMMARY

[0006] In view of the deficiencies of the prior art, the purpose of the present application is to provide a host compound, a double-host material and an organic electroluminescent device. The first host compound with a specific structure has a faster hole mobility, and the second host compound has a faster electron mobility. The first host compound and the second host compound with a specific structure are used in the present application to balance the hole and electron mobilities, so that the double-host material can increase the excitons in the emission layer, not only improving the light-emitting efficiency and service life of the device, but also reducing the driving voltage.

[0007] To achieve the object of the present application, the present application adopts the following technical solutions:

[0008] In one aspect, the present application provides a host compound having a structure shown in Formula I:

[0009] ;

[0010] wherein ring A is selected from substituted or unsubstituted phenanthrene, substituted or unsubstituted anthracene;

[0011] ring B, ring C are each independently selected from substituted or unsubstituted C6-C42 aryl, substituted or unsubstituted C6-C30 heteroaryl, substituted or unsubstituted C10-C30 fused ring group, substituted or unsubstituted C10-C42 arylamine group; and at least one of ring B, ring C is selected from substituted or unsubstituted C10-C42 arylamine group;

[0012] Z is selected from O or S;

[0013] m is selected from 0 or 1;

[0014] L1, L2 are each independently selected from any one of a bond, substituted or unsubstituted C6-C30 arylene, substituted or unsubstituted C6-C30 heteroarylene, substituted or unsubstituted C10-C30 fused ring group, substituted or unsubstituted C10-C42 arylamine group;

[0015] All hydrogens in Formula I are unsubstituted by deuterium, partially substituted by deuterium or completely substituted by deuterium.

[0016] In the present application, the bond refers to a single bond.

[0017] Further preferably, ring B, ring C are each independently selected from substituted or unsubstituted C6-C18 aryl, substituted or unsubstituted C6-C18 heteroaryl, substituted or unsubstituted C10-C18 fused ring group, substituted or unsubstituted C10-C42 arylamine group; and at least one of ring B, ring C is selected from substituted or unsubstituted C10-C42 arylamine group.

[0018] Further preferably, L1, L2 are each independently selected from any one of a bond, substituted or unsubstituted C6-C18 arylene, substituted or unsubstituted C6-C18 heteroarylene, substituted or unsubstituted C10-C18 fused ring group, substituted or unsubstituted C10-C30 arylamine group.

[0019] According to one embodiment of the present application, the host compound has a structure shown in any one of Formula I-A to Formula I-J:

[0020] ;

[0021] wherein ring B, ring C are each independently selected from the group consisting of phenyl, naphthyl, biphenyl, dibenzofuranyl, dibenzothiophenyl, phenanthryl, phenyl- substituted naphthyl, phenyl-substituted dibenzofuranyl, phenyl-substituted dibenzothiophenyl or the following groups:

[0022] ;

[0023] ;

[0024] L1, L2 are each independently selected from the group consisting of a bond, phenyl, naphthyl, biphenyl, dibenzofuranyl, dibenzothiophenyl, phenanthryl, phenyl- substituted naphthyl, phenyl-substituted dibenzofuranyl, phenyl-substituted dibenzothiophenyl or the following groups, which are fully or partially substituted with deuterium or unsubstituted:

[0025] ;

[0026] wherein is a group attachment site and D represents deuterium.

[0027] Further, the host compound has a structure represented by any one of formulae I-H-1 to I-H-8:

[0028] .

[0029] In the present application, the heteroaryl group is a monocyclic aromatic group containing at least one heteroatom and / or a polycyclic aromatic ring group containing at least one heteroatom, the heteroatom being O, S, N, P, Si or B.

[0030] The term "substituted" means substituted with one, two or more substituents selected from the group consisting of cyano, methyl, ethyl, propyl, butyl, tert-butyl, cyclopentane, cyclohexane, phenyl, biphenyl, naphthyl, fluorenyl, dimethylfluorenyl, phenanthryl, triphenylenyl, furanyl, thiophenyl, pyrrolyl, pyridyl, benzofuranyl, benzothiophenyl, isobenzofuranyl, dibenzofuranyl or dibenzothiophenyl, or substituted with at least two substituents connected to each other.

[0031] In the present application, the host compound is any one of the compounds represented by formulae H1-1 to H1-528, but is not limited thereto:

[0032]

[0033]

[0034]

[0035]

[0036]

[0037]

[0038] ;

[0039] wherein D represents deuterium.

[0040] In a second aspect, the present application also provides a dual host material, the dual host material comprising a first host compound and a second host compound, the first host compound being the host compound as described above;

[0041] the second host compound has a structure as shown in formula II:

[0042] ;

[0043] wherein L3, L4 are each independently selected from any one of a direct bond, a substituted or unsubstituted C6-C30 arylene, a substituted or unsubstituted C6-C30 heteroarylene, a substituted or unsubstituted C10-C30 fused ring group;

[0044] Ar1and Ar2are each independently selected from any one of a substituted or unsubstituted C6-C42 aryl, a substituted or unsubstituted C6-C42 heteroaryl, a substituted or unsubstituted phosphorine oxide, a substituted or unsubstituted silyl, a substituted or unsubstituted C10-C42 fused ring group;

[0045] Ar3 is selected from substituted or unsubstituted C6-C42 aryl and substituted or unsubstituted C3-C42 heteroaryl groups;

[0046] The heteroaryl group is a monocyclic aromatic group containing at least one heteroatom and / or a polycyclic aromatic ring group containing at least one heteroatom, wherein the heteroatom is O, S, N, P, B or Si.

[0047] The substituents include deuterium, fluorine, cyano, or C1-C6 straight-chain or branched alkyl groups and phenyl groups.

[0048] Furthermore, L3 and L4 are each independently selected from any one of the following: a linking bond, a substituted or unsubstituted C6-C18 arylene, a substituted or unsubstituted C6-C18 heteroarylene, or a substituted or unsubstituted C10-C18 fused ring group.

[0049] Furthermore, Ar1 and Ar2 are each independently selected from any one of substituted or unsubstituted C6-C18 aryl, substituted or unsubstituted C6-C18 heteroaryl, substituted or unsubstituted phosphoxy, substituted or unsubstituted silyl, or substituted or unsubstituted C10-C18 fused cyclic groups.

[0050] Furthermore, Ar3 is selected from substituted or unsubstituted C6-C18 aryl groups and substituted or unsubstituted C3-C18 heteroaryl groups.

[0051] Furthermore, L3 and L4 are each independently selected from any one of the following: linking bond, phenylene, naphthylene, thiopheneyl, and furanylene.

[0052] Ar1 and Ar2 are independently selected from phenyl, deuterated phenyl, naphthyl, deuterated naphthyl, anthracene, biphenyl, thiophene, chromyl, furanyl, phenyl-furanyl, furanyl-deuterated phenyl, naphthiophene, phenanthiophene, tri-benzofuranyl, pyrene-furanyl, phenanthiophene, tert-butylphenyl, benzoxazine, phenyl-thiophene, fluorenyl, diphenyl-fluorenyl, dibenzocarbazoyl, naphthiobenzocarbazoyl, phenanthiobenzocarbazoyl, phenylbenzoxazole, phenylnaphthoxazole, and benzene, respectively. The following groups are included: phenanthrene-1, phenylcarbazo-1, phenylnaphtho-1, phenyldibenzofuran-1, phenyldrozo-1, phenyldibenzofluoren-1, phenyltriphenyl-1, phenylbenzothiazole, phenylnaphthothiazole, phenylphenanthrene-1, fluoranyl, phenylyl, pyrene, naphthobenzofluorenyl, peryl, naphthothianyl, triphenylene, phenylnaphthyl, dibenzofuranyl, dibenzothiopheneyl, cyanophenyl, benzophenanthryl, tetraphenylgermanyl, benzonaphthoselenophenolyl, or any one of the following groups:

[0053]

[0054] in for a group attachment site.

[0055] In the present application, the second host compound is any one of compounds represented by formulae H2-1 to H2-408, but is not limited thereto:

[0056]

[0057]

[0058]

[0059]

[0060]

[0061]

[0062]

[0063]

[0064]

[0065]

[0066] ;

[0067] wherein D represents deuterium.

[0068] In one embodiment of the present application, the mass ratio of the first host compound to the second host compound is (10~90):(90~10), for example, 10:90, 15:85, 20:80, 25:75, 30:70, 35:65, 40:60, 45:55, 50:50, 60:40, 70:30, 80:20, or 90:10, preferably 60~40:40~60.

[0069] The defined carbon number range of the group in the present application means including any integer of carbon atom number within the defined range, for example, C6-C30 means that the carbon atom number of the group can be 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29 or 30, and the defined carbon number range of other groups is similar.

[0070] In a third aspect, the present application further provides a preparation method of the host compound having a structure shown in formula I.

[0071] Synthesis of compound formula I:

[0072] Synthesis of compound formula I:

[0073]

[0074] Synthesis of compound formula I:

[0075] Under the nitrogen protection system, the raw material A1 (1 eq), the raw material A2 (1-1.1 eq), potassium carbonate (2.5-3 eq) are weighed and put into the reaction system, toluene, ethanol, water and catalyst tetrakis (triphenylphosphine) palladium (0.05-0.1 eq) are added, under the nitrogen protection, 90-100℃ reflux for 20-24h, after the reaction is completed, it is cooled to 25℃, pure water is added, stirred and then placed for separation, after the separation treatment, column chromatography is used for purification, to obtain the intermediate compound formula I-1;

[0076] Under the nitrogen protection system, the raw material A3 (1 eq), the raw material A4 (1-1.1 eq), potassium carbonate (2.5-3 eq) are weighed and put into the reaction system, toluene, ethanol, water and catalyst tetrakis (triphenylphosphine) palladium (0.05-0.1 eq) are added, under the nitrogen protection, 90-100℃ reflux for 20-24h, after the reaction is completed, it is cooled to 25℃, pure water is added, stirred and then placed for separation, after the separation treatment, column chromatography is used for purification, to obtain the intermediate compound formula I-2;

[0077] Under the nitrogen protection system, the intermediate compound formula I-1 (1 eq), the raw material A5 (1-1.2 eq), potassium acetate (2.5-3.0 eq) are put into the reaction system, 1,4-dioxane, catalyst tris (dibenzylideneacetone) dipalladium (0.01-0.02 eq), ligand x-phos (2-bicyclohexylphosphine-2', 4', 6'-triisopropyl biphenyl, 0.04-0.08 eq) are added, reflux reaction is carried out at 100-110℃ for 18~24h, after the reaction is completed, it is reduced to 25℃, pure water is added, stirred and then placed for separation, after the separation treatment, column chromatography is used for purification, to obtain the intermediate compound formula I-3.

[0078] Under the nitrogen protection system, the intermediate compound formula I-2 (1 eq), raw material A5 (1-1.2 eq), potassium acetate (2.5-3.0 eq) are put into the reaction system, 1,4-dioxane, catalyst tris (dibenzyl ketone) palladium (0.01-0.02 eq), ligand x-phos (2-bicyclohexyl phosphine-2', 4', 6'-triisopropyl biphenyl, 0.04-0.08 eq) are added, and the reaction is refluxed at 100-110℃ for 18-24h. After the reaction is completed, it is cooled to 25℃, pure water is added, stirred and then separated, and the obtained product is purified by column chromatography to obtain the intermediate compound formula I-4.

[0079] Under the nitrogen protection system, the intermediate compound formula I-3 (1 eq), raw material A6 (1-1.1 eq), potassium carbonate (2.5-3 eq) are put into the reaction system, toluene, ethanol, water and catalyst tetrakis (triphenylphosphine) palladium (0.05-0.1 eq) are added, and the reaction is refluxed at 90-100℃ for 20-24h under nitrogen protection. After the reaction is completed, it is cooled to 25℃, pure water is added, stirred and then separated, and the obtained product is purified by column chromatography to obtain the intermediate compound formula I-5.

[0080] Under the nitrogen protection system, the intermediate compound formula I-5 (1 eq), intermediate compound formula I-4 (1-1.1 eq), potassium carbonate (2.5-3.0 eq) are put into the reaction system, toluene, ethanol, water and catalyst tetrakis (triphenylphosphine) palladium (0.05-0.1 eq) are added, and the reaction is refluxed at 90-100℃ for 20-24h under nitrogen protection. After the reaction is completed, it is cooled to 25℃, pure water is added, stirred and then separated, and the obtained product is purified by column chromatography to obtain the intermediate compound formula I.

[0081] In the formula, ring A, ring B, ring C, L1, L2, m and Z are independently selected from the same range as formula I; X is selected from halogen; the halogen includes fluorine, chlorine, bromine or iodine, preferably chlorine, bromine, and most preferably chlorine.

[0082] In a fourth aspect, the application further provides a preparation method of the host compound with the structure of formula II.

[0083] In an embodiment of the application, the reaction route of the second host compound with the structure of formula II is as follows:

[0084] .

[0085] The specific preparation method includes:

[0086] (1) Under the nitrogen protection system, the reactant 1 (1 eq), the reactant 2 (1-1.1 eq), potassium carbonate (2.5-3 eq) are weighed and put into the reaction system, toluene, ethanol, water and catalyst tetrakis (triphenylphosphine) palladium (0.02-0.05 eq) are added, under the nitrogen protection, refluxing at 90-100 ℃ for 20-24 h, after the reaction is completed, cooling to 25 ℃, pure water is added, stirring and then standing to separate the layers, after the liquid separation treatment, the intermediate compound of formula II-1 is obtained by column chromatography purification;

[0087] (2) Under the nitrogen protection system, the intermediate compound of formula II-1 (1 eq), the reactant 2-1 (1-1.1 eq), potassium carbonate (2.5-3 eq) are weighed and put into the reaction system, toluene, ethanol, water and catalyst tetrakis (triphenylphosphine) palladium (0.02-0.05 eq) are added, under the nitrogen protection, refluxing at 90-100 ℃ for 20-24 h, after the reaction is completed, cooling to 25 ℃, pure water is added, stirring and then standing to separate the layers, after the liquid separation treatment, the intermediate compound of formula II-2 is obtained by column chromatography purification;

[0088] (3) Under the nitrogen protection system, the intermediate compound of formula II-2 (1 eq), the reactant 2-2 (1-1.1 eq), potassium carbonate (2.5-3 eq) are weighed and put into the reaction system, toluene, ethanol, water and catalyst tetrakis (triphenylphosphine) palladium (0.02-0.05 eq) are added, under the nitrogen protection, refluxing at 90-100 ℃ for 20-24 h, after the reaction is completed, cooling to 25 ℃, pure water is added, stirring and then standing to separate the layers, after the liquid separation treatment, the second host compound of formula II is obtained by column chromatography purification.

[0089] In a fifth aspect, the present application further provides an organic electroluminescent material, which comprises the double-host material.

[0090] Preferably, the organic electroluminescent material further comprises a dopant material.

[0091] Preferably, the mass ratio of the double-host material to the dopant material in the organic electroluminescent material is (5-199):1, for example, 5:1, 8:1, 10:1, 15:1, 20:1, 25:1, 30:1, 35:1, 40:1, 50:1, 60:1, 70:1, 80:1, 90:1, 100:1, 120:1, 130:1, 140:1, 150:1, 160:1, 170:1, 180:1, 190:1 or 199:1, etc. Further preferably, (5-100):1, and more preferably, (5-15):1.

[0092] In a sixth aspect, the present application also provides an organic electroluminescent device comprising a first electrode, a second electrode, and an organic layer disposed between the first electrode and the second electrode, the organic layer comprising an emission layer, the emission layer comprising the above-mentioned double host material or the above-mentioned organic electroluminescent material.

[0093] In the present application, the organic layer further comprises any one or a combination of at least two of a hole injection layer, a hole transport layer, an emission layer, a hole blocking layer, an electron transport layer, and an electron injection layer.

[0094] In the present application, the preparation method of the emission layer includes, but is not limited to, forming the organic electroluminescent material into an emission layer by a solution coating method and a vacuum deposition method; the solution coating method means spin coating, dip coating, inkjet printing, screen printing, spraying, etc., but is not limited thereto.

[0095] In the present application, the first electrode is an anode.

[0096] In the present application, as an anode material, a material with a large work function is generally preferred in order to enable holes to be smoothly injected into an organic layer.

[0097] In the present application, the anode material includes metals such as vanadium, chromium, copper, zinc, or alloys thereof; metal oxides such as zinc oxide, indium oxide, indium tin oxide (ITO), or indium zinc oxide (IZO); combinations of metals and oxides such as ZnO / Al or SnO2 / Sb; conductive polymers such as poly(3-methylthiophene), polypyrrole, or polyaniline; but is not limited thereto.

[0098] In the present application, the anode is an ITO anode.

[0099] In the present application, 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 layer material is preferably between the work function of the anode material and the HOMO of the surrounding organic material layer.

[0100] In the present application, the hole injection material includes metal porphyrin, oligothiophene, arylamine-based organic material, benzonitrile-based organic material, quinacridone-based organic material, polyaniline-based or polythiophene-based conductive polymer.

[0101] In the present application, 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 emission layer, and has a high hole mobility.

[0102] In the present application, the hole transport layer material includes an arylamine-based organic material, a conductive polymer, a block copolymer having both a conjugated portion and a non-conjugated portion, etc., but is not limited thereto.

[0103] In the present application, the electron transport layer functions to facilitate electron transport, and the electron transport layer material is a material for receiving electrons from a cathode and transporting the electrons to a light-emitting layer, having a high electron mobility.

[0104] In the present application, the electron transport layer material includes an Al complex of 8-hydroxyquinoline; an organic radical compound.

[0105] In the present application, the electron transport layer has a thickness of 1 nm to 50 nm, for example, 1 nm, 2 nm, 4 nm, 6 nm, 8 nm, 10 nm, 15 nm, 20 nm, 25 nm, 30 nm, 35 nm, 40 nm, 45 nm, 50 nm.

[0106] The electron transport layer can prevent a decrease in electron transport characteristics and an increase in driving voltage due to the electron transport layer being too thick.

[0107] In the present application, the electron injection layer can function to facilitate electron injection, and the electron injection material preferably has the ability to transport electrons, has an electron injection effect from a cathode, has an excellent electron injection effect on a light-emitting layer or a light-emitting material, prevents excitons generated in the light-emitting layer from migrating to a hole injection layer, and in addition thereto, has an excellent thin film formation ability.

[0108] In the present application, the electron injection layer material includes one or more of fluorenone, anthraquinone dimethane, diphenylquinone, thiopyran dioxide, imidazole, perylene tetracarboxylic acid, fluorenyl methanone, anthrone, etc., and derivatives thereof, a metal complex, and a nitrogen-containing five-membered ring derivative.

[0109] In the present application, the second electrode is a cathode.

[0110] As a cathode material, a material having a small work function is generally preferred in order to easily inject electrons into an organic layer.

[0111] In one embodiment of the present application, the cathode material includes a metal such as magnesium, calcium, sodium, potassium, titanium, indium, yttrium, lithium, gadolinium, aluminum, silver, tin, lead, etc., or an alloy thereof; a multi-layered structure material such as LiF / Al or LiO2 / Al; but is not limited thereto. In some embodiments of the present application, the cathode material is Al.

[0112] In the present application, the organic electroluminescent device can be a top emission type, a bottom emission type, or a dual side emission type.

[0113] The numerical ranges recited herein include all values from and including the lower and upper values. This is true even if the values included in the lower or upper range are outside of the recited range. The ranges are provided for the convenience of the reader and are not intended to limit the scope of the application. Unless otherwise stated, the numerical ranges and parameters setting forth the broad scope of the application are approximations. The numerical values set forth in the specific examples are reported as precisely as possible. Any numerical value, however, can contain certain errors associated with the measurement of the given example.

[0114] Compared with the prior art, the present application has the following beneficial effects:

[0115] The double-host material provided by the present application has a first host compound with a specific structure and a second host compound, the first host compound with the specific structure has a faster hole mobility, and the second host compound has a faster electron mobility. The double-host material of the present application combines two different characteristic hosts, by compounding the first host compound and the second host compound with the specific structure, as the light-emitting layer material of the organic electroluminescent device, the hole and electron mobility can be balanced, so that the double-host material increases the excitons in the light-emitting layer, not only improves the luminous efficiency and service life of the device, but also reduces the driving voltage. BRIEF DESCRIPTION OF DRAWINGS

[0116] Figure 1 NMR chart of the first host compound H1-93 prepared in Example 1. DETAILED DESCRIPTION

[0117] The technical solutions of the present application will be further described below through specific embodiments. Those skilled in the art should understand that the embodiments are only to help understand the present application, and should not be regarded as specific limitations of the present application.

[0118] In addition, 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, not an absolutely accurate number.

[0119] Unless otherwise specified, the raw materials and reagents used in the following examples are commercially available.

[0120] Reference is made to the following well-known knowledge:

[0121] Transition Metal Organometallic Chemistry (Original Sixth 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.

[0122] Organic Chemistry and Optoelectronic Material Experiment Tutorial, Chen Runfeng, Publisher: Southeast University Press, Publication Time: 2019-11-00, ISBN: 9787564184230, Page 174.

[0123] The features and properties of the present application will be further described in detail below with specific reference to the preparation examples.

[0124] Preparation Example 1

[0125] Preparation of the first host compound H1-93

[0126] Under a nitrogen protection system, raw material 93-1 (1 eq), raw material 93-2 (1.0 eq), potassium carbonate (2 eq) were put into the reaction system, and tetrakis(triphenylphosphine)palladium (0.02 eq), toluene, ethanol, water were added, and the temperature was raised to 90°C and refluxed for 20 hours. After the reaction was completed, pure water and dichloromethane were added, stirred and then allowed to stand and separate into layers. After the liquid-liquid treatment, the intermediate compound of formula 93-1 was obtained by column chromatography purification.

[0127] Under a nitrogen protection system, intermediate compound of formula 93-1 (1 eq), raw material 93-3 (1 eq), potassium acetate (2.5 eq) were put into the reaction system, and 1,4-dioxane, catalyst tris(dibenzylideneacetone)dipalladium (0.01 eq), ligand x-phos (2-dicyclohexylphosphino-2',4',6'-triisopropylbiphenyl, 0.08 eq) were added, and the temperature was raised to 100°C and refluxed for 24 hours. After the reaction was completed, the temperature was lowered to 25°C, and pure water was added. After stirring and then allowed to stand and separate into layers, the liquid-liquid treatment was performed, and the intermediate compound of formula 93-2 was obtained by column chromatography purification.

[0128] Under a nitrogen protection system, intermediate 93-2 (1 eq), raw material 93-4 (1.0 eq), potassium carbonate (2 eq) were put into the reaction system, and tetrakis(triphenylphosphine)palladium (0.02 eq), toluene, ethanol, water were added, and the temperature was raised to 90°C and refluxed for 20 hours. After the reaction was completed, pure water and dichloromethane were added, stirred and then allowed to stand and separate into layers. After the liquid-liquid treatment, the intermediate compound of formula 93-3 was obtained by column chromatography purification.

[0129] Under a nitrogen protection system, intermediate compound of formula 93-3 (1 eq), (methoxymethyl)triphenoxyphosphonium chloride (1.3 eq) and THF were added to the reaction system and stirred for 10 minutes. A solution of potassium tert-butoxide was slowly added dropwise at 0°C. Then, the temperature was slowly raised, and after stirring at room temperature for 3 hours, distilled water was added. After the reaction was completed, the organic layer was extracted with ethyl acetate, and the organic phase was dried with sodium sulfate. The solvent was removed by a rotary evaporator, and then the intermediate compound of formula 93-4 was purified by column chromatography.

[0130] Under the protection of nitrogen, intermediate compound formula 93-4, boron trifluoride etherate and dichloromethane were added into the reaction system 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 then the solvent was removed with a rotary evaporator, and then it was purified by column chromatography to obtain the intermediate compound formula 93-5.

[0131] Under the protection of nitrogen, intermediate 93-5 (1 eq), raw material 93-5 (1 eq), sodium tert-butoxide (1.5 eq) were placed into the reaction system, toluene, catalyst tris (dibenzylideneacetone) palladium (0.02 eq), ligand 50% tri-tert-butyl phosphine (0.04 eq) were added, and the reaction was refluxed at 120℃ for 18~24 h. After the reaction was completed, it was cooled to 25℃, pure water was added, stirred and then separated into layers, and then purified by column chromatography to obtain the compound H1-270. (17.20 g, yield 63.50%, HPLC >99%, mass spectrometry test value 652.40, element analysis test value C: 86.46; H: 4.30; N: 4.30;), and the reaction scheme is shown below.

[0132]

[0133] The nuclear magnetic resonance hydrogen spectrum of H1-93 is shown in Figure 1 .

[0134] Preparation Example 2

[0135] Preparation of the second main compound H2-199

[0136] Under the protection of nitrogen, the reactants 199-1 (1 eq), the reactants 199-2 (1 eq), potassium carbonate (2.5 eq) were placed into the reaction system, toluene, ethanol, water, catalyst tetrakis (triphenylphosphine) palladium (0.04 eq) were added, and then the reaction was refluxed at 90℃ for 24 h under the protection of nitrogen, and then cooled to 25℃, filtered, and then the solid was column chromatographed to obtain the compound H2-199 (13.40 g, yield 67.30%, HPLC >99%, mass spectrometry test value: 549.35), and the reaction scheme is shown below.

[0137]

[0138] In addition, it should be noted that other compounds of the present application can be obtained by referring to the synthesis methods of the preparation examples listed above, so they will not be listed one by one here.

[0139] Examples 1~110, Comparative Examples 1~57

[0140] Examples 1~110, Comparative Examples 1~57 respectively provide a host material, the formulation of which is shown in Table 1, wherein, for the scheme of double host material including the first host compound and the second host compound, the mass ratio of the first host compound and the second host compound is 60:40. In Table 1, "-" indicates that there is no such compound in the host material; the structures of D-1 to D-8 are respectively as shown below.

[0141] .

[0142] The method for preparing the organic electroluminescent device comprises the following steps:

[0143] (1) The ITO (indium tin oxide) glass substrate with a thickness of 1500 Å is cleaned in distilled water for 2 times, ultrasonic washing for 30 min, and then repeatedly cleaned in distilled water for 2 times, ultrasonic washing for 10 min. After washing, the substrate is sequentially ultrasonic washed in methanol, acetone and isopropanol (5 min each time), dried, and then transferred to a plasma cleaning machine for washing for 5 min to obtain an ITO anode.

[0144] (2) In the evaporation machine, a HIL is vacuum evaporated on the surface of the ITO anode obtained in step (1), with a thickness of 200 Å, to obtain a hole injection layer.

[0145] (3) A HTL is vacuum evaporated on the surface of the hole injection layer obtained in step (2), with a thickness of 400 Å, to obtain a hole transport layer.

[0146] (4) The material of the light-emitting layer is evaporated on the surface of the hole transport layer, and linear gradient co-evaporation is performed by using multi-source co-evaporation, with a thickness of 300 Å, to obtain a light-emitting layer; the material of the light-emitting layer includes a double host material and a doping material, the mass ratio of the first host compound and the second host compound is 60:40, and the mass ratio of the double host material and the doping material is 10:1; the double host material is respectively the host material provided in Examples 1~110, Comparative Examples 1~57.

[0147] (5) BAlq is evaporated on the surface of the light-emitting layer obtained in step (4), with a thickness of 100 Å, to form a hole blocking layer.

[0148] (6) An ETL is vacuum evaporated on the surface of the hole blocking layer obtained in step (5), with a thickness of 400 Å, to obtain an electron transport layer.

[0149] (7) Liq is vacuum evaporated on the surface of the electron transport layer obtained in step (6), with a thickness of 15 Å, to obtain an electron injection layer.

[0150] (8) Al with a thickness of 1500 Å is evaporated on the surface of the electron injection layer obtained in step (7) to form a cathode, thereby obtaining the organic electroluminescent device.

[0151] The structures of the materials used in the above preparation method are as follows:

[0152]

[0153] The driving voltage, luminous efficiency and time (lifetime; T95) taken for the luminance to decrease from 100% to 95% at a luminance of 5000 nits of the organic electroluminescent device were tested, and the test results are shown in Table 1.

[0154] Table 1

[0155]

[0156] As can be seen from Table 1, the double-host material provided by the application, using the first host compound and the second host compound with specific structures, can reduce the driving voltage of the device, improve the luminous efficiency of the device, and prolong the service life of the device.

[0157] As can be seen from the comparison of Examples 1-110 and Comparative Examples 1-57, the use of the first host compound and the second host compound to compound the host material of the light-emitting layer can greatly improve the luminous efficiency and service life. If only one of them is selected, the luminous efficiency of the device will be greatly reduced, the service life will be significantly shortened, and the voltage will be increased, regardless of which one is selected.

[0158] As can be seen from Examples 1-110 and Comparative Examples 9-24, the luminous efficiency of Comparative Examples 9-24 is 32.1-33.6 cd / A, the driving voltage is 3.50-3.62 V, and the lifetime is 321-343 h. The luminous efficiency of Examples 1-110 of the application is 37.5-46.3 cd / A, which is significantly higher than that of Comparative Examples 9-24. The driving voltage of Examples 1-110 of the application is 3.21-3.36 V, which is significantly lower than that of Comparative Examples 9-24. The lifetime of Examples 1-110 of the application is 461-554 h, which is much higher than that of Comparative Examples 9-24.

[0159] This is because the first host compound provided by the application has a CN group connected to the furan ring or the thiophene ring, which makes the first host compound have a lower LOMO, makes the light-emitting spectrum red-shift to the deep red light band, is more conducive to improving the luminous efficiency, is more conducive to improving the charge mobility, and the fused ring of phenanthrene, anthracene, etc. and the CN group construct a rigid molecular structure, making the spatial structure more compact, the thin film stacking morphology is good, and it is more conducive to prolonging the service life of the device, especially the The mother nucleus structure formed by the 3, 4 positions of phenanthrene and the furan ring or the thiophene ring has a larger conjugated system, and after being connected with the arylamine hole transport segment, the intermolecular force can be enhanced, the hole mobility of the compound is significantly improved, the second host compound has faster electron mobility, by compounding the first host compound and the second host compound with specific structures to serve as the light-emitting layer material of the organic electroluminescent device, the hole and electron mobility can be balanced, the exciton in the light-emitting layer is increased, the luminous efficiency and service life of the device are improved, and the driving voltage is reduced.

[0160] Therefore, when the light-emitting layer host material is compounded by the first host compound with a specific structure and the second host compound with a specific structure, the luminous efficiency and service life can be greatly improved.

[0161] It can be known from the test results of the comparative examples 1-8 and the comparative examples 25-57 that the light-emitting layer material includes the first host compound with a specific structure provided by the application, and the performance of the device is slightly higher than that of the single host compound in the prior art, and the performance of the host material provided by the application is more excellent.

[0162] The applicant declares that the host compound, the double host material and the organic electroluminescent device of the application are illustrated by the above examples, but the application is not limited to the above examples, that is, it does not mean that the application must rely on the above examples to be implemented. It should be understood by those skilled in the art that any improvement of the application, equivalent replacement of the selected materials of the application, addition of auxiliary ingredients, selection of specific modes, etc. fall within the protection scope and disclosure scope of the application.

Claims

1. A host compound, characterized in that, The host compound has the structure shown in Formula I: ； Wherein, ring A is selected from unsubstituted phenanthrene and unsubstituted anthracene; rings B and C are each independently selected from the following groups that are fully substituted with deuterium, partially substituted with deuterium, or unsubstituted: phenyl, naphthyl, biphenyl, dibenzofuranyl, dibenzothiophene, phenanthrene, benzene-substituted naphthyl, benzene-substituted dibenzofuranyl, benzene-substituted dibenzothiophene, or the following groups: ； ； L1 and L2 are each independently selected from the linking bond and are either completely or partially substituted by deuterium, or unsubstituted, of the following groups: phenyl, naphthyl, biphenyl, dibenzofuranyl, dibenzothiophene, phenanthryl, benzene-substituted naphthyl, benzene-substituted dibenzofuranyl, benzene-substituted dibenzothiophene, or the following groups: ； in This is the group linkage site, where D represents deuterium; In Formula I, all hydrogen atoms are either unsubstituted by deuterium, partially substituted by deuterium, or completely substituted by deuterium.

2. The main compound according to claim 1, characterized in that, The host compound has a structure shown in any one of formulas IA-IJ: 。 3. The host compound according to claim 1, characterized in that, The host compound has a structure shown in any one of formulas IH-1 to IH-8: 。 4. The host compound according to claim 1, characterized in that, The host compound is any one of the compounds shown in formula H1-1 to formula H1-528: ； Where D represents deuterium.

5. A dual-body material, characterized in that, The dual-host material comprises a first host compound and a second host compound, wherein the first host compound is the host compound according to any one of claims 1-4; The second host compound has the structure shown in Formula II: ； Among them, L3 and L4 are independently selected from any one of the following: linking bond, phenylene, naphthylene, thiopheneyl, and furanylene; Ar1 and Ar2 are independently selected from phenyl, deuterated phenyl, naphthyl, deuterated naphthyl, anthracene, biphenyl, thiophene, furanyl, phenyl-furanyl, furanyl-deuterated phenyl, naphthiophene, phenanthiophene, tri-benzofuranyl, pyrene-furanyl, phenanthiophene, tert-butylphenyl, benzoxazine, phenyl-thiophene, fluorenyl, diphenyl-fluorenyl, dibenzocarbazoyl, naphthiobenzocarbazoyl, phenanthiobenzocarbazoyl, phenylbenzoxazole, phenylnaphthoxazole, phenylphenanthrene. Benzoxazole, phenylcarbazole, phenylnaphthooxazole, phenyldibenzofuranoxazole, phenyldronexaazole, phenyldibenzofluorenoxazole, phenyltriphenylbenzooxazole, phenylbenzothiazole, phenylnaphthothiazole, phenylphenanthrenethiazole, fluoranyl, phenylyl, pyrene, naphthobenzofluorenyl, peryl, naphthothianyl, triphenylene, phenylnaphthyl, dibenzofuranyl, dibenzothiopheneyl, cyanophenyl, benzophenanthreneyl, tetraphenylgermanyl, benzonaphthoselenophenolyl, or any one of the following groups: ； in For group linkage sites; Ar3 is selected from unsubstituted C6-C18 aryl groups.

6. The dual-body material according to claim 5, characterized in that, The second host compound is any one of the compounds shown in formula H2-1 to formula H2-408: ； Where D represents deuterium; The mass ratio of the first main compound to the second main compound is (10~90):(90~10).

7. An organic electroluminescent device, characterized in that, The organic electroluminescent device includes a first electrode, a second electrode, and an organic layer disposed between the first electrode and the second electrode, wherein the organic layer includes a light-emitting layer, and the light-emitting layer includes the dual-body material as described in claim 5 or 6; The organic layer further includes any one or a combination of at least two of the following: a hole injection layer, a hole transport layer, a light-emitting layer, a hole blocking layer, an electron transport layer, and an electron injection layer.

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