CN112778283B

CN112778283B - Organic electroluminescent material and device thereof

Info

Publication number: CN112778283B
Application number: CN201911084832.5A
Authority: CN
Inventors: 王强; 王乐; 邝志远; 夏传军
Original assignee: Beijing Summer Sprout Technology Co Ltd
Current assignee: Beijing Summer Sprout Technology Co Ltd
Priority date: 2019-11-08
Filing date: 2019-11-08
Publication date: 2023-02-03
Anticipated expiration: 2039-11-08
Also published as: CN112778283A

Abstract

An organic electroluminescent material and a device thereof are disclosed. The organic electroluminescent material is a compound with an arylamine substituted indenocarbazole structure, and can be used as a main body material in an electroluminescent device. These novel compounds provide better device performance. Also discloses a compound formula.

Description

Organic electroluminescent material and device thereof

Technical Field

The present invention relates to compounds for use in organic electronic devices, such as organic electroluminescent devices. More particularly, the invention relates to a compound with an arylamine substituted indenocarbazole structure, an organic electroluminescent device containing the compound and a compound formula.

Background

Organic electronic devices include, but are not limited to, the following: organic Light Emitting Diodes (OLEDs), organic field effect transistors (O-FETs), organic Light Emitting Transistors (OLETs), organic Photovoltaics (OPVs), dye-sensitized solar cells (DSSCs), organic optical detectors, organic photoreceptors, organic field effect devices (OFQDs), light emitting electrochemical cells (LECs), organic laser diodes, and organic plasma light emitting devices.

In 1987, tang and Van Slyke, by Isman Kodak, reported a two-layer organic electroluminescent device comprising an arylamine hole transport layer and a tris-8-hydroxyquinoline-aluminum layer as an electron transport layer and a light-emitting layer (Applied Physics Letters,1987,51 (12): 913-915). Upon biasing the device, green light is emitted from the device. The invention lays a foundation for the development of modern Organic Light Emitting Diodes (OLEDs). State-of-the-art OLEDs may include multiple layers, such as charge injection and transport layers, charge and exciton blocking layers, and one or more light emitting layers between the cathode and anode. Since OLEDs are a self-emissive solid state device, it offers great potential for display and lighting applications. Furthermore, the inherent properties of organic materials, such as their flexibility, may make them well suited for particular applications, such as in the fabrication of flexible substrates.

OLEDs can be classified into three different types according to their light emitting mechanism. The OLEDs invented by Tang and van Slyke are fluorescent OLEDs. It uses only singlet luminescence. The triplet states generated in the device are wasted through the non-radiative decay channel. Therefore, the Internal Quantum Efficiency (IQE) of fluorescent OLEDs is only 25%. This limitation hinders the commercialization of OLEDs. In 1997, forrest and Thompson reported phosphorescent OLEDs, which use triplet emission from complex-containing heavy metals as emitters. Thus, singlet and triplet states can be harvested, achieving 100% IQE. Due to its high efficiency, the discovery and development of phosphorescent OLEDs directly contributes to the commercialization of Active Matrix OLEDs (AMOLEDs). Recently, adachi achieved high efficiency through Thermally Activated Delayed Fluorescence (TADF) of organic compounds. These emitters have a small singlet-triplet gap, making it possible to return excitons from the triplet state to the singlet state. In TADF devices, triplet excitons are capable of generating singlet excitons through reverse intersystem crossing, resulting in high IQE.

OLEDs can also be classified into small molecule and polymer OLEDs depending on the form of the material used. Small molecule refers to any organic or organometallic material that is not a polymer. The molecular weight of small molecules can be large, as long as they have a precise structure. Dendrimers with well-defined structures are considered small molecules. The polymer OLED comprises a conjugated polymer and a non-conjugated polymer having pendant light-emitting groups. Small molecule OLEDs can become polymer OLEDs if post-polymerization occurs during the fabrication process.

Various OLED fabrication methods exist. Small molecule OLEDs are typically fabricated by vacuum thermal evaporation. Polymer OLEDs are fabricated by solution processes such as spin coating, ink jet printing, and nozzle printing. Small molecule OLEDs can also be made by solution processes if the material can be dissolved or dispersed in a solvent.

The light emitting color of the OLED can be realized by the structural design of the light emitting material. An OLED may comprise one light emitting layer or a plurality of light emitting layers to achieve a desired spectrum. Green, yellow and red OLEDs, phosphorescent materials have been successfully commercialized. Blue phosphorescent devices still have the problems of blue unsaturation, short device lifetime, high operating voltage, and the like. Commercial full-color OLED displays typically employ a hybrid strategy using either blue fluorescent and phosphorescent yellow, or red and green. At present, the rapid decrease in efficiency of phosphorescent OLEDs at high luminance is still a problem. In addition, it is desirable to have a more saturated emission spectrum, higher efficiency and longer device lifetime.

U.S. Pat. No. 6,989,774A 1 discloses compounds having an indenocarbazole unit linked to a quinazoline structure of the general formula

The concrete structure is that

The use of triarylamine substitution in such compounds by incorporation on the indenocarbazole ring is not disclosed and taught. In addition, the reported compound is used as an electron transport material, and the application of the compound as a host material is not clear.

CN108779072A discloses a compound having an indenocarbazole unit linked to quinazoline structure, which has a general formula shown in the specification

The concrete structure is as follows

However, the application of the triarylamine substitution on the indenocarbazole ring in the compound is not disclosed and taught, and the disclosed compound is used as a main material for an organic electronic device and has higher voltage.

U.S. Pat. No. 5,983,06237,1 discloses quinazolino linkages in indenocarbazole units and triarylamine substitution in the carbazole moiety, having the general formula

The concrete structure is that

However, the application of triarylamine substitution in the indeno ring part of the indenocarbazole ring is not disclosed and taught, and the disclosed compound is used as a main material for organic electronic devices with higher voltage.

CN105849107A discloses a compound with an indenocarbazole unit linked quinazoline structure, which has the following general formula

The concrete structure is as follows

The use of triarylamine substitution in such compounds by incorporation on the indenocarbazole ring is not disclosed and taught.

These documents disclose compounds having an indenocarbazole ring as a core structure, and have a nitrogen heterocyclic ring substitution introduced into carbazole. The inventor of the invention finds that a novel bipolar compound is constructed by taking an indenocarbazole ring as a core, introducing nitrogen heterocycle with excellent electron transport capability on carbazole and introducing triarylamine with excellent hole transport capability on indene for substitution, and when the bipolar compound is used in an organic light-emitting device, the bipolar compound can provide better device performance.

Disclosure of Invention

The present invention aims to provide a series of compounds having a novel indenocarbazole structure, which are useful as host materials in organic electroluminescent devices. The novel compounds are applied to organic light-emitting devices and can provide better device performance.

According to one embodiment of the present invention, a compound comprising the structure of formula 1 is disclosed:

wherein Y is ₁ To Y ₄ Is selected from N, one of the other two is selected from C, and the other is selected from CR _y ；

Wherein, Y ₅ To Y ₈ Each independently selected from N or CR _y ；

Wherein L is _y Is a single bond, or a substituted or unsubstituted arylene group having 6 to 30 carbon atoms, or a substituted or unsubstituted heteroarylene group having 3 to 30 carbon atoms;

wherein, X ₁ To X ₄ Each independently selected from N or CR _x1 ；X ₅ To X ₈ Each independently selected from N, C or CR _x2 Wherein X is ₅ To X ₈ Two adjacent of them are C, and are arbitrarily connected with two positions shown in formula 1A;

wherein L is _x Is a single bond, or a substituted or unsubstituted arylene group having 6 to 30 carbon atoms, or a substituted or unsubstituted heteroarylene group having 3 to 30 carbon atoms;

wherein, Z ₁ To Z ₄ Independently selected from N, C or CR _z ；

Wherein each occurrence of Ar, the same or different, is selected from a substituted or unsubstituted aryl group having 6 to 30 carbon atoms, or a substituted or unsubstituted heteroaryl group having 3 to 30 carbon atoms;

wherein the adjacent substituents R _x1 Can be optionally linked to form a ring;

wherein R is _x1 ，R _x2 ，R _y ，R _z And R is selected, identically or differently on each occurrence, from the group consisting of: hydrogen, deuterium, halogen, substituted or unsubstituted alkyl having 1 to 20 carbon atoms, substituted or unsubstituted cycloalkyl having 3 to 20 ring carbon atoms, substituted or unsubstituted heteroalkyl having 1 to 20 carbon atoms, substituted or unsubstituted aralkyl having 7 to 30 carbon atoms, substituted or unsubstituted alkoxy having 1 to 20 carbon atoms, substituted or unsubstituted aryloxy having 6 to 30 carbon atoms, substituted or unsubstituted alkenyl having 2 to 20 carbon atoms, substituted or unsubstituted alkenyl having 6 to 30 carbon atomsAn aryl group of atoms, a substituted or unsubstituted heteroaryl group having 3 to 30 carbon atoms, a substituted or unsubstituted alkylsilyl group having 3 to 20 carbon atoms, a substituted or unsubstituted arylsilyl group having 6 to 20 carbon atoms, a substituted or unsubstituted amine group having 0 to 20 carbon atoms, an acyl group, a carbonyl group, a carboxylic acid group, an ester group, a cyano group, an isocyano group, a thio group, a sulfinyl group, a sulfonyl group, a phosphino group, and combinations thereof.

According to another embodiment of the present invention, there is also disclosed an electroluminescent device comprising an anode, a cathode, and an organic layer disposed between the anode and the cathode, the organic layer comprising the compound, the compound comprising the structure of formula 1.

According to another embodiment of the present invention, a compound formulation comprising the compound, the compound comprising the structure of formula 1, is also disclosed.

The novel compound with the indenocarbazole structure can be used as a main body material in an electroluminescent device. The novel bipolar compounds are applied to organic light-emitting devices, can effectively balance carriers in a light-emitting layer, and provide better device performance, such as lower driving voltage.

Drawings

FIG. 1 is a schematic representation of an organic light emitting device that can contain the compounds and compound formulations disclosed herein.

Fig. 2 is a schematic representation of another organic light-emitting device that can contain the compounds and compound formulations disclosed herein.

Detailed Description

OLEDs can be fabricated on a variety of substrates, such as glass, plastic, and metal. Fig. 1 schematically, but without limitation, illustrates an organic light emitting device 100. The figures are not necessarily to scale, and some of the layer structures in the figures may be omitted as desired. The device 100 may include a substrate 101, an anode 110, a hole injection layer 120, a hole transport layer 130, an electron blocking layer 140, an emissive layer 150, a hole blocking layer 160, an electron transport layer 170, an electron injection layer 180, and a cathode 190. The device 100 may be fabricated by sequentially depositing the described layers. The nature and function of the various layers and exemplary materials are described in more detail in U.S. Pat. No. 7,279,704B2 at columns 6-10, which is incorporated herein by reference in its entirety.

There are more instances of each of these layers. For example, a flexible and transparent substrate-anode combination is disclosed in U.S. Pat. No. 5,844,363, which is incorporated by reference in its entirety. An example of a p-doped hole transport layer is doped with F at a molar ratio of 50 ₄ -TCNQ m-MTDATA as disclosed in U.S. patent application publication No. 2003/0230980, incorporated by reference in its entirety. Examples of host materials are disclosed in U.S. patent No. 6,303,238 to Thompson et al, which is incorporated by reference in its entirety. An example of an n-doped electron transport layer is BPhen doped with Li at a molar ratio of 1. U.S. Pat. Nos. 5,703,436 and 5,707,745, which are incorporated by reference in their entirety, disclose examples of cathodes including a composite cathode having a thin layer of a metal such as Mg: ag with an overlying transparent, conductive, sputter-deposited ITO layer. The principles and use of barrier layers are described in more detail in U.S. patent No. 6,097,147 and U.S. patent application publication No. 2003/0230980, which are incorporated by reference in their entirety. Examples of implant layers are provided in U.S. patent application publication No. 2004/0174116, which is incorporated by reference in its entirety. A description of a protective layer can be found in U.S. patent application publication No. 2004/0174116, which is incorporated by reference in its entirety.

The above-described hierarchical structure is provided via non-limiting embodiments. The function of the OLED may be achieved by combining the various layers described above, or some layers may be omitted entirely. It may also include other layers not explicitly described. Within each layer, a single material or a mixture of materials may be used to achieve optimal performance. Any functional layer may comprise several sub-layers. For example, the light emitting layer may have two layers of different light emitting materials to achieve a desired light emission spectrum.

In one embodiment, an OLED may be described as having an "organic layer" disposed between a cathode and an anode. The organic layer may include one or more layers.

The OLED also requires an encapsulation layer, as shown in fig. 2, which is an exemplary, non-limiting illustration of an organic light emitting device 200, which differs from fig. 1 in that an encapsulation layer 102 may also be included over the cathode 190 to protect against harmful substances from the environment, such as moisture and oxygen. Any material capable of providing an encapsulation function may be used as the encapsulation layer, such as glass or a hybrid organic-inorganic layer. The encapsulation layer should be placed directly or indirectly outside the OLED device. Multilayer film encapsulation is described in U.S. Pat. No. 7,968,146b2, the entire contents of which are incorporated herein by reference.

Devices manufactured according to embodiments of the present invention may be incorporated into various consumer products having one or more electronic component modules (or units) of the device. Some examples of such consumer products include flat panel displays, monitors, medical monitors, televisions, billboards, lights for indoor or outdoor lighting and/or signaling, head-up displays, fully or partially transparent displays, flexible displays, smart phones, tablet computers, tablet handsets, wearable devices, smart watches, laptop computers, digital cameras, camcorders, viewfinders, micro-displays, 3-D displays, vehicle displays, and tail lights.

The materials and structures described herein may also be used in the other organic electronic devices listed previously.

As used herein, "top" means furthest from the substrate, and "bottom" means closest to the substrate. Where a first layer is described as being "disposed on" a second layer, the first layer is disposed farther from the substrate. Unless it is specified that a first layer is "in contact with" a second layer, there may be other layers between the first and second layers. For example, a cathode can be described as being "disposed on" an anode even though various organic layers are present between the cathode and the anode.

As used herein, "solution processable" means capable of being dissolved, dispersed or transported in and/or deposited from a liquid medium in the form of a solution or suspension.

A ligand may be referred to as "photoactive" when it is believed that the ligand directly contributes to the photoactive properties of the emissive material. A ligand may be referred to as "ancillary" when it is believed that the ligand does not contribute to the photoactive properties of the emissive material, but the ancillary ligand may alter the properties of the photoactive ligand.

It is believed that the Internal Quantum Efficiency (IQE) of a fluorescent OLED can be statistically limited by delaying fluorescence by more than 25% spin. Delayed fluorescence can generally be divided into two types, i.e., P-type delayed fluorescence and E-type delayed fluorescence. P-type delayed fluorescence results from triplet-triplet annihilation (TTA).

On the other hand, E-type delayed fluorescence does not depend on collision of two triplet states, but on conversion between triplet and singlet excited states. Compounds capable of producing E-type delayed fluorescence need to have a very small mono-triplet gap in order to switch between energy states. Thermal energy can activate a transition from a triplet state back to a singlet state. This type of delayed fluorescence is also known as Thermally Activated Delayed Fluorescence (TADF). A significant feature of TADF is that the retardation component increases with increasing temperature. If the reverse intersystem crossing (IRISC) rate is fast enough to minimize non-radiative decay from the triplet state, the fraction of the back-filled singlet excited states may reach 75%. The total singlet fraction may be 100%, far exceeding 25% of the spin statistics of the electrogenerated excitons.

The delayed fluorescence characteristic of type E can be found in excited complex systems or in single compounds. Without being bound by theory, it is believed that E-type delayed fluorescence requires the light emitting material to have a small mono-triplet energy gap (Δ Ε) _S-T ). Organic non-metal containing donor-acceptor emissive materials may be able to achieve this. The emission of these materials is generally characterized as donor-acceptor Charge Transfer (CT) type emission. Spatial separation of HOMO from LUMO in these donor-acceptor type compounds generally results in small Δ E _S-T . These states may include CT states. Generally, donor-acceptor light emitting materials are constructed by linking an electron donor moiety (e.g., an amino or carbazole derivative) to an electron acceptor moiety (e.g., a six-membered, N-containing, aromatic ring).

Definition of terms with respect to substituents

Halogen or halide-as used herein, includes fluorine, chlorine, bromine and iodine.

Alkyl-comprises both straight and branched chain alkyl groups. Examples of alkyl groups include methyl, ethyl, propyl, isopropyl, n-butyl, sec-butyl, isobutyl, tert-butyl, n-pentyl, n-hexyl, n-heptyl, n-octyl, n-nonyl, n-decyl, n-undecyl, n-dodecyl, n-tridecyl, n-tetradecyl, n-pentadecyl, n-hexadecyl, n-heptadecyl, n-octadecyl, neopentyl, 1-methylpentyl, 2-methylpentyl, 1-pentylhexyl, 1-butylpentyl, 1-heptyloctyl, 3-methylpentyl. In addition, the alkyl group may be optionally substituted. The carbons in the alkyl chain may be substituted with other heteroatoms. Among the above, methyl, ethyl, propyl, isopropyl, n-butyl, sec-butyl, isobutyl, tert-butyl, n-pentyl and neopentyl are preferable.

Cycloalkyl-as used herein, comprises a cyclic alkyl group. Preferred cycloalkyl groups are those containing 4 to 10 ring carbon atoms and include cyclobutyl, cyclopentyl, cyclohexyl, 4-methylcyclohexyl, 4-dimethylcyclohexyl, 1-adamantyl, 2-adamantyl, 1-norbornyl, 2-norbornyl and the like. In addition, cycloalkyl groups may be optionally substituted. The carbon in the ring may be substituted with other heteroatoms.

Alkenyl-as used herein, encompasses straight and branched chain alkene groups. Preferred alkenyl groups are those containing 2 to 15 carbon atoms. Examples of alkenyl groups include vinyl, allyl, 1-butenyl, 2-butenyl, 3-butenyl, 1, 3-butadienyl, 1-methylvinyl, styryl, 2-diphenylvinyl, 1-methylallyl, 1-dimethylallyl, 2-methylallyl, 1-phenylallyl, 2-phenylallyl, 3-diphenylallyl, 1, 2-dimethylallyl, 1-phenyl-1-butenyl and 3-phenyl-1-butenyl. In addition, alkenyl groups may be optionally substituted.

Alkynyl-as used herein, straight and branched alkynyl groups are contemplated. Preferred alkynyl groups are those containing 2 to 15 carbon atoms. In addition, alkynyl groups may be optionally substituted.

Aryl or aromatic-as used herein, non-fused and fused systems are contemplated. Preferred aryl groups are those containing from 6 to 60 carbon atoms, more preferably from 6 to 20 carbon atoms, and even more preferably from 6 to 12 carbon atoms. Examples of aryl groups include phenyl, biphenyl, terphenyl, triphenylene, tetraphenylene, naphthalene, anthracene, phenalene, phenanthrene, fluorene, pyrene, chicory, perylene and azulene, preferably phenyl, biphenyl, terphenyl, triphenylene, fluorene and naphthalene. In addition, the aryl group may be optionally substituted. Examples of non-fused aryl groups include phenyl, biphenyl-2-yl, biphenyl-3-yl, biphenyl-4-yl, p-terphenyl-3-yl, p-triphenyl-2-yl, m-terphenyl-4-yl, m-terphenyl-3-yl, m-terphenyl-2-yl, o-tolyl, m-tolyl, p- (2-phenylpropyl) phenyl, 4 '-methyldiphenyl, 4' -tert-butyl-p-terphenyl-4-yl, o-cumyl, m-cumyl, p-cumyl, 2, 3-xylyl, 3, 4-xylyl, 2, 5-xylyl, mesitylene and m-quaterphenyl groups.

Heterocyclyl or heterocyclic-as used herein, aromatic and non-aromatic cyclic groups are contemplated. Heteroaryl also refers to heteroaryl. Preferred non-aromatic heterocyclic groups are those containing 3 to 7 ring atoms, which include at least one heteroatom such as nitrogen, oxygen and sulfur. The heterocyclic group may also be an aromatic heterocyclic group having at least one hetero atom selected from a nitrogen atom, an oxygen atom, a sulfur atom and a selenium atom.

Heteroaryl-as used herein, non-fused and fused heteroaromatic groups are contemplated which may contain 1 to 5 heteroatoms. Preferred heteroaryl groups are those containing from 3 to 30 carbon atoms, more preferably from 3 to 20 carbon atoms, more preferably from 3 to 12 carbon atoms. Suitable heteroaryl groups include dibenzothiophene, dibenzofuran, dibenzoselenophene, furan, thiophene, benzofuran, benzothiophene, benzoselenophene, carbazole, indolocarbazole, pyridine indole, pyrrolopyridine, pyrazole, imidazole, triazole, oxazole, thiazole, oxadiazole, bisoxazole, thiadiazole, pyridine, pyridazine, pyrimidine, pyrazine, triazine, oxazine, oxathiazine, oxadiazine, indole, benzimidazole, indazole, indenozine, benzoxazole, benzisoxazole, benzothiazole, quinoline, isoquinoline, quinoline, quinazoline, quinoxaline, naphthyridine, phthalazine, pteridine, xanthene, acridine, phenazine, phenothiazine, benzothienopyridine, thienobipyridine, benzothienopyridine, thienobipyridine, benzothiophene, cinnoline, selenobenzene, dibenzofuran, dibenzoselenophene, carbazole, indolocarbazole, imidazole, pyridine, triazine, benzimidazole, 1, 2-azaborine, 1, 3-azaborine, 1, 4-azaborine, azaborizole and analogs thereof. In addition, the heteroaryl group may be optionally substituted.

Alkoxy-is represented by-O-alkyl. Examples and preferred examples of the alkyl group are the same as those described above. Examples of the alkoxy group having 1 to 20 carbon atoms, preferably 1 to 6 carbon atoms include methoxy, ethoxy, propoxy, butoxy, pentyloxy, and hexyloxy. The alkoxy group having 3 or more carbon atoms may be linear, cyclic or branched.

Aryloxy-is represented by-O-aryl or-O-heteroaryl. Examples and preferred examples of aryl and heteroaryl groups are the same as described above. Examples of the aryloxy group having 6 to 40 carbon atoms include a phenoxy group and a biphenyloxy group.

Aralkyl-as used herein, an alkyl group having an aryl substituent. In addition, the aralkyl group may be optionally substituted. Examples of the aralkyl group include a benzyl group, a 1-phenylethyl group, a 2-phenylethyl group, a 1-phenylisopropyl group, a 2-phenylisopropyl group, a phenyl tert-butyl group, an α -naphthylmethyl group, a 1- α -naphthyl-ethyl group, a 2- α -naphthylethyl group, a 1- α -naphthylisopropyl group, a 2- α -naphthylisopropyl group, a β -naphthylmethyl group, a 1- β -naphthylethyl group, a 2- β -naphthylethyl group, a 1- β -naphthylisopropyl group, a 2- β -naphthylisopropyl group, a p-methylbenzyl group, a m-methylbenzyl group, a o-methylbenzyl group, a p-chlorobenzyl group, a m-chlorobenzyl group, a p-chlorobenzyl group, a m-bromobenzyl group, a p-iodobenzyl group, a m-iodobenzyl group, a p-hydroxybenzyl group, a m-hydroxybenzyl group, a o-hydroxybenzyl group, a p-aminobenzyl group, an m-aminobenzyl group, a p-nitrobenzyl group, a m-nitrobenzyl group, an o-cyanobenzyl group, a 1-2-phenylisopropyl group and a 1-chloro-2-isopropylyl group. Among the above, benzyl, p-cyanobenzyl, m-cyanobenzyl, o-cyanobenzyl, 1-phenylethyl, 2-phenylethyl, 1-phenylisopropyl and 2-phenylisopropyl are preferable.

The term "aza" in aza-dibenzofuran, aza-dibenzothiophene, etc., means that one or more C-H groups in the corresponding aromatic moiety are replaced by a nitrogen atom. For example, azatriphenylene includes dibenzo [ f, h ] quinoxaline, dibenzo [ f, h ] quinoline and other analogs having two or more nitrogens in the ring system. Other nitrogen analogs of the aza derivatives described above will be readily apparent to one of ordinary skill in the art, and all such analogs are intended to be encompassed by the term as described herein.

In this disclosure, unless otherwise defined, when any one of the terms in the group consisting of: substituted alkyl groups, substituted cycloalkyl groups, substituted heteroalkyl groups, substituted aralkyl groups, substituted alkoxy groups, substituted aryloxy groups, substituted alkenyl groups, substituted aryl groups, substituted heteroaryl groups, substituted silyl groups, substituted arylsilyl groups, substituted amine groups, substituted acyl groups, substituted carbonyl groups, substituted carboxylic acid groups, substituted ester groups, substituted cyano groups, substituted isocyano groups, substituted sulfanyl groups, substituted sulfonyl groups, substituted phosphino groups, which means alkyl groups, cycloalkyl groups, heteroalkyl groups, aralkyl groups, alkoxy groups, aryloxy groups, alkenyl groups, aryl groups, heteroaryl groups, alkylsilyl groups, amine groups, acyl groups, carbonyl groups, carboxylic acid groups, ester groups, cyano groups, isocyano groups, sulfanyl groups, sulfinyl groups, sulfonyl groups, and phosphino groups, any of which may be substituted with one or more groups selected from deuterium, unsubstituted alkyl groups having 1 to 20 carbon atoms, unsubstituted cycloalkyl groups having 3 to 20 carbon atoms, unsubstituted heteroalkyl groups having 1 to 20 carbon atoms, unsubstituted aralkyl groups having 7 to 30 carbon atoms, unsubstituted alkoxy groups having 1 to 20 carbon atoms, unsubstituted aryl groups having 2 to 20 carbon atoms, unsubstituted alkoxycarbonyl groups having 3 to 20 carbon atoms, unsubstituted alkoxycarbonyl groups, substituted alkoxycarbonyl groups having 3 to 3 carbon atoms, sulfinyl, sulfonyl, phosphino, and combinations thereof.

It will be understood that when a molecular fragment is described as a substituent or otherwise attached to another moiety, its name may be written depending on whether it is a fragment (e.g., phenyl, phenylene, naphthyl, dibenzofuranyl) or depending on whether it is an entire molecule (e.g., benzene, naphthalene, dibenzofuran). As used herein, these different ways of specifying substituents or linking fragments are considered to be equivalent.

In the compounds mentioned in the present disclosure, a hydrogen atom may be partially or completely replaced by deuterium. Other atoms such as carbon and nitrogen may also be replaced by their other stable isotopes. Substitution of other stable isotopes in the compounds may be preferred because it enhances the efficiency and stability of the device.

In the compounds mentioned in the present disclosure, polysubstitution is meant to encompass disubstituted substitutions up to the maximum range of available substitutions. When a substituent in a compound mentioned in the present disclosure represents multiple substitution (including di-substitution, tri-substitution, tetra-substitution, etc.), that is, it means that the substituent may exist at a plurality of available substitution positions on its connecting structure, and the substituent existing at each of the plurality of available substitution positions may be the same structure or different structures.

In the compounds mentioned in the present disclosure, adjacent substituents in the compounds cannot be linked to form a ring unless specifically defined, for example, adjacent substituents can be optionally linked to form a ring. In the compounds mentioned in the present disclosure, adjacent substituents can be optionally linked to form a ring, including both the case where adjacent substituents may be linked to form a ring and the case where adjacent substituents are not linked to form a ring. When adjacent substituents can optionally be joined to form a ring, the ring formed can be monocyclic or polycyclic, as well as alicyclic, heteroalicyclic, aromatic or heteroaromatic rings. In this expression, adjacent substituents may refer to substituents bonded to the same atom, substituents bonded to carbon atoms directly bonded to each other, or substituents bonded to carbon atoms further away. Preferably, adjacent substituents refer to substituents bonded to the same carbon atom as well as substituents bonded to carbon atoms directly bonded to each other.

The expression that adjacent substituents can optionally be linked to form a ring is also intended to mean that two substituents bonded to the same carbon atom are linked to each other by a chemical bond to form a ring, which can be exemplified by the following formula:

the expression that adjacent substituents can optionally be linked to form a ring is also intended to mean that two substituents bonded to carbon atoms directly bonded to each other are linked to each other by a chemical bond to form a ring, which can be exemplified by the following formula:

further, the expression that adjacent substituents can be optionally connected to form a ring is also intended to be taken to mean that, in the case where one of two substituents bonded to carbon atoms directly bonded to each other represents hydrogen, the second substituent is bonded at a position to which the hydrogen atom is bonded, thereby forming a ring. This is exemplified by the following equation:

according to one embodiment of the present invention, there is disclosed a compound comprising the structure of formula 1:

Wherein, Y ₅ To Y ₈ Each independently selected from N or CR _y ；

wherein, X ₁ To X ₄ Each independently selected from N or CR _x1 ；X ₅ To X ₈ Each independently selected from N, C or CR _x2 ；X ₅ To X ₈ Two of them are adjacent to each other and are randomly connected with the positions shown by two in the formula 1A;

wherein, Z ₁ To Z ₄ Each independently selected from N, C or CR _z ；

Wherein each occurrence of Ar, the same or different, is selected from substituted or unsubstituted aryl groups having 6 to 30 carbon atoms, or substituted or unsubstituted heteroaryl groups having 3 to 30 carbon atoms;

wherein R is _x1 ，R _x2 ，R _y ，R _z And R is selected, identically or differently on each occurrence, from the group consisting of: hydrogen, deuterium, halogen, substituted or unsubstituted alkyl having 1 to 20 carbon atoms, substituted or unsubstituted cycloalkyl having 3 to 20 ring carbon atoms, substituted or unsubstituted heteroalkyl having 1 to 20 carbon atoms, substituted or unsubstituted aralkyl having 7 to 30 carbon atoms, substituted or unsubstituted alkoxy having 1 to 20 carbon atoms, substituted or unsubstituted aryloxy having 6 to 30 carbon atoms, substituted or unsubstituted alkenyl having 2 to 20 carbon atoms, substituted or unsubstituted aryl having 6 to 30 carbon atoms, substituted or unsubstituted heteroaryl having 3 to 30 carbon atoms, substituted or unsubstituted alkylsilicon having 3 to 20 carbon atomsA group, a substituted or unsubstituted arylsilane group having 6 to 20 carbon atoms, a substituted or unsubstituted amine group having 0 to 20 carbon atoms, an acyl group, a carbonyl group, a carboxylic acid group, an ester group, a cyano group, an isocyano group, a thio group, a sulfinyl group, a sulfonyl group, a phosphino group, and combinations thereof.

According to one embodiment of the present invention, the compound is selected from the group consisting of the following formulas 2-1 to 2-6:

wherein, Y ₁ To Y ₈ ，X ₁ To X ₈ ，Z ₁ To Z ₄ ，R，Ar，L _x And L _y Having the same limitations as in formula 1 and formula 1A.

According to one embodiment of the present invention, the compound is selected from the group consisting of the following formulas 2-7 to 2-12:

wherein Y is ₁ ，Y ₅ To Y ₈ ，X ₁ To X ₈ ，Z ₁ To Z ₄ ，R，Ar，L _x And L _y Having the same limitations as in formula 1 and formula 1A.

According to an embodiment of the invention, wherein Y ₁ ，Y ₅ To Y ₈ Each independently selected from CR _y Wherein R is _y Each occurrence, the same or different, is selected from the group consisting of: hydrogen, deuterium, substituted or unsubstituted aryl radicals having 6 to 30 carbon atoms, or a mixture thereofSubstituted or unsubstituted heteroaryl groups having 3 to 30 carbon atoms, and combinations thereof.

According to one embodiment of the present invention, wherein X ₁ To X ₄ Each independently selected from CR _x1 Wherein X is ₅ -X ₈ Two of which are adjacent and selected from C, the remaining two are each independently selected from CR _x2 Wherein R is _x1 And R _x2 Each occurrence, the same or different, is selected from the group consisting of: hydrogen, deuterium, substituted or unsubstituted aryl groups having 6 to 30 carbon atoms, substituted or unsubstituted heteroaryl groups having 3 to 30 carbon atoms, and combinations thereof.

According to an embodiment of the invention, wherein Z ₁ To Z ₄ One of which is selected from C and the others are each independently selected from N or CR _z Wherein R is _z Each occurrence, the same or different, is selected from the group consisting of: hydrogen, deuterium, substituted or unsubstituted aryl groups having 6 to 30 carbon atoms, substituted or unsubstituted heteroaryl groups having 3 to 30 carbon atoms, and combinations thereof.

According to one embodiment of the present invention, wherein Y ₁ ，Y ₅ To Y ₈ Each independently selected from CR _y ；

X ₁ To X ₄ Each independently selected from CR _X1 ，X ₅ -X ₈ Two of them are adjacent and selected from C, and the other two are each independently selected from CR _X2 ；

Z ₁ To Z ₄ One of which is selected from C and the others are each independently selected from CR _z ；

R _y ，R _X1 ，R _X2 And R _z The same or different at each occurrence is selected from the group consisting of: hydrogen, deuterium, substituted or unsubstituted aryl groups having 6 to 30 carbon atoms, substituted or unsubstituted heteroaryl groups having 3 to 30 carbon atoms, and combinations thereof.

According to an embodiment of the invention, wherein L _x And L _y Each independently selected from a single bond, a substituted or unsubstituted arylene group having 6 to 12 carbon atoms, and a substituted or unsubstituted heteroarylene group having 3 to 12 carbon atoms.

According to an embodiment of the invention, wherein L _x And L _y Each independently selected from a single bond, or a substituted or unsubstituted phenylene group.

According to one embodiment of the invention, wherein R, the same or different at each occurrence, is a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms, a substituted or unsubstituted cycloalkyl group having 3 to 20 ring carbon atoms, a substituted or unsubstituted aryl group having 6 to 30 carbon atoms, a substituted or unsubstituted heteroaryl group having 3 to 30 carbon atoms, and combinations thereof; preferably, R is selected, identically or differently on each occurrence, from the group consisting of: methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, tert-butyl, phenyl, and combinations thereof.

According to one embodiment of the invention, wherein Ar, on each occurrence, is selected, identically or differently, from the group consisting of: a substituted or unsubstituted phenyl group, a substituted or unsubstituted fluorenyl group, a substituted or unsubstituted carbazolyl group, a substituted or unsubstituted dibenzothiapyrrolyl group, a substituted or unsubstituted dibenzofuranyl group, a substituted or unsubstituted dibenzothiophenyl group, and combinations thereof.

According to one embodiment of the invention, wherein Ar, on each occurrence, is selected, identically or differently, from the group consisting of:

a substituted or unsubstituted phenyl group, a substituted or unsubstituted fluorenyl group, a substituted or unsubstituted carbazolyl group, a substituted or unsubstituted dibenzothiapyrrolyl group, a substituted or unsubstituted dibenzofuranyl group, a substituted or unsubstituted dibenzothiophenyl group, a substituted or unsubstituted dibenzoselenophenyl group, and combinations thereof; preferably, ar is selected, identically or differently at each occurrence, from the group consisting of: phenyl, biphenyl, pyridine, cyanophenyl, fluorenyl, dimethylfluorenyl, diphenylfluorenyl, carbazolyl, phenylcarbazolyl, dibenzothiazolyl, dimethyldibenzothiazolyl, diphenyldibenzothiazolyl, biphenyl, terphenyl, phenanthrenyl, triphenylene, spirobifluorenyl, dibenzofuranyl, dibenzothienyl, dibenzoselenophenyl, azadibenzofuranyl, azadibenzothienyl, azadibenzoselenophenyl, and combinations thereof.

According to one embodiment of the present invention, the compound is selected from the group consisting of compound 1 to compound 567, wherein the specific structures of compound 1 to compound 567 are set forth in claim 11.

According to an embodiment of the present invention, there is also disclosed an electroluminescent device, including:

an anode, a cathode, a anode and a cathode,

a cathode electrode, which is provided with a cathode,

and an organic layer disposed between the anode and the cathode, the organic layer comprising the compound, the compound comprising a structure represented by formula 1:

wherein Y is ₁ To Y ₄ Any two of which are selected from N, one of the remaining two is selected from C, and the other is selected from CR _y ；

Wherein, Y ₅ To Y ₈ Each independently selected from N or CR _y ；

wherein X ₁ To X ₄ Each independently selected from N or CR _x1 ；X ₅ To X ₈ Each independently selected from N, C or CR _x2 ；X ₅ To X ₈ Two of them are adjacent to each other and are randomly connected with the positions shown by two in the formula 1A;

wherein, Z ₁ To Z ₄ Each independently selected from N, C orCR _z ；

wherein the adjacent substituents R _x1 Optionally joined to form a ring;

wherein R is _x1 ，R _x2 ，R _y ，R _z And R is selected, identically or differently on each occurrence, from the group consisting of: hydrogen, deuterium, halogen, a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms, a substituted or unsubstituted cycloalkyl group having 3 to 20 ring carbon atoms, a substituted or unsubstituted heteroalkyl group having 1 to 20 carbon atoms, a substituted or unsubstituted arylalkyl group having 7 to 30 carbon atoms, a substituted or unsubstituted alkoxy group having 1 to 20 carbon atoms, a substituted or unsubstituted aryloxy group having 6 to 30 carbon atoms, a substituted or unsubstituted alkenyl group having 2 to 20 carbon atoms, a substituted or unsubstituted aryl group having 6 to 30 carbon atoms, a substituted or unsubstituted heteroaryl group having 3 to 30 carbon atoms, a substituted or unsubstituted alkylsilyl group having 3 to 20 carbon atoms, a substituted or unsubstituted arylsilyl group having 6 to 20 carbon atoms, a substituted or unsubstituted amine group having 0 to 20 carbon atoms, an acyl group, a carbonyl group, a carboxylic acid group, an ester group, a cyano group, an isocyano group, a thio group, a sulfinyl group, a sulfonyl group, a phosphino group, and combinations thereof.

According to one embodiment of the present invention, in the device, the organic layer is a light emitting layer and the compound is a host material.

According to an embodiment of the invention, in the device, the organic layer further comprises a phosphorescent light emitting material.

According to one embodiment of the invention, in the device, the phosphorescent light emitting material is a metal complex having at least one ligand comprising the structure of any one of:

wherein, the first and the second end of the pipe are connected with each other,

X _b selected from the group consisting of: o, S, se, NR _N1 And CR _C1 R _C2 ；

X _c And X _d Each independently selected from the group consisting of: o, S, se, NR _N2 ；

R _a ，R _b ，R _c May represent mono-, poly-, or unsubstituted, and may be the same or different at each occurrence;

R _a ，R _b ，R _c ，R _N1 ，R _N2 ，R _C1 and R _C2 Each occurrence, the same or different, is selected from the group consisting of: hydrogen, deuterium, halogen, a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms, a substituted or unsubstituted cycloalkyl group having 3 to 20 ring carbon atoms, a substituted or unsubstituted heteroalkyl group having 1 to 20 carbon atoms, a substituted or unsubstituted arylalkyl group having 7 to 30 carbon atoms, a substituted or unsubstituted alkoxy group having 1 to 20 carbon atoms, a substituted or unsubstituted aryloxy group having 6 to 30 carbon atoms, a substituted or unsubstituted alkenyl group having 2 to 20 carbon atoms, a substituted or unsubstituted aryl group having 6 to 30 carbon atoms, a substituted or unsubstituted heteroaryl group having 3 to 30 carbon atoms, a substituted or unsubstituted alkylsilyl group having 3 to 20 carbon atoms, a substituted or unsubstituted arylsilyl group having 6 to 20 carbon atoms, a substituted or unsubstituted amine group having 0 to 20 carbon atoms, an acyl group, a carbonyl group, a carboxylic acid group, an ester group, a nitrile, an isonitrile, a thio group, a sulfinyl group, a sulfonyl group, a phosphino group, and combinations thereof;

in the ligand structure, adjacent substituents can optionally be linked to form a ring.

In this example, the expression that adjacent substituents in the ligand structure can optionally be linked to form a ring is intended to be taken to mean that adjacent substituents in the ligand structure can optionally be linked to one another by a chemical bond, such as substituent R _a And R _b Of a substituent R _a And R _c Of R is a substituent _b And R _c A substituent groupR _C1 And R _C2 And when the substituent R is _a 、R _b And/or R _c When multiple substitution is indicated, two adjacent substituents R _a Two substituents R adjacent to each other _b Two substituents R adjacent to each other _c In the meantime. Furthermore, it is obvious to a person skilled in the art that adjacent substituents R in the ligand structure _a 、R _b 、R _c 、R _N1 ，R _N2 ，R _C1 And R _C2 May not be connected therebetween.

According to one embodiment of the present invention, in the device, wherein the phosphorescent light emitting material is an Ir, pt or Os complex.

According to one embodiment of the present invention, the device, wherein the phosphorescent light emitting material is an Ir complex and has Ir (L) _a )(L _b )(L _c ) The structure of (1); wherein L is _a ，L _b And L _c Ligands selected, identically or differently, from any of the above.

According to an embodiment of the invention, in the device, wherein the phosphorescent light emitting material is selected from the group consisting of:

wherein, X _f Each occurrence, the same or different, is selected from the group consisting of: o, S, se, NR _N3 ,CR _C3 R _C4 ；

Wherein, X _e Selected, identically or differently at each occurrence, from being CR _d Or N;

R _a ,R _b and R _c May represent mono-, poly-, or unsubstituted, and may be the same or different at each occurrence;

R _a ，R _b ，R _c ，R _d ，R _N3 ，R _C3 and R _C4 Each occurrence, the same or different, is selected from the group consisting of: hydrogen, deuterium, halogen, a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms, a substituted or unsubstituted cycloalkyl group having 3 to 20 ring carbon atoms, a substituted or unsubstituted heteroalkyl group having 1 to 20 carbon atoms, a substituted or unsubstituted arylalkyl group having 7 to 30 carbon atoms, a substituted or unsubstituted alkoxy group having 1 to 20 carbon atoms, a substituted or unsubstituted aryloxy group having 6 to 30 carbon atoms, a substituted or unsubstituted alkenyl group having 2 to 20 carbon atoms, a substituted or unsubstituted aryl group having 6 to 30 carbon atoms, a substituted or unsubstituted heteroaryl group having 3 to 30 carbon atoms, a substituted or unsubstituted alkylsilyl group having 3 to 20 carbon atoms, a substituted or unsubstituted arylsilyl group having 6 to 20 carbon atoms, a substituted or unsubstituted amine group having 0 to 20 carbon atoms, an acyl group, a carbonyl group, a carboxylic acid group, an ester group, a nitrile, an isonitrile, a thio group, a sulfinyl group, a sulfonyl group, a phosphino group, and combinations thereof;

adjacent substituents can optionally be linked to form a ring.

In this example, the expression that adjacent substituents in the ligand structure can optionally be linked to form a ring is intended to be taken to mean that adjacent substituents in the ligand structure can optionally be linked to each other by a chemical bond, such as substituent R _a And R _b Of R is a substituent _a And R _c Of R is a substituent _b And R _c Of a substituent R _d And R _b Of R is a substituent _C3 And R _C4 And, when the substituent R is _a 、R _b And/or R _c When multiple substitution is indicated, two adjacent substituents R _a Between, adjacent two substituents R _b Two substituents R adjacent to each other _c In the meantime. Furthermore, it is obvious to a person skilled in the art that adjacent substituents R in the ligand structure _a 、R _b 、R _c 、R _d 、R _N3 、R _C3 And R _C4 May not be connected therebetween.

According to another embodiment of the present invention, there is also disclosed a compound formulation comprising the compound, the compound comprising the structure represented by formula 1. The specific structure of the compound is shown in any one of the embodiments.

In combination with other materials

The materials described herein for use in particular layers in an organic light emitting device may be used in combination with various other materials present in the device. Combinations of these materials are described in detail in U.S. patent application US2016/0359122A1, paragraphs 0132-0161, the entire contents of which are incorporated herein by reference. The materials described or referenced therein are non-limiting examples of materials that can be used in combination with the compounds disclosed herein, and one skilled in the art can readily review the literature to identify other materials that can be used in combination.

Materials described herein as being useful for particular layers in an organic light emitting device can be used in combination with a variety of other materials present in the device. For example, the materials disclosed herein may be used in conjunction with a variety of light emitting dopants, hosts, transport layers, barrier layers, injection layers, electrodes, and other layers that may be present. Combinations of these materials are described in detail in U.S. patent application US2015/0349273A1, paragraphs 0080-0101, which is incorporated herein by reference in its entirety. The materials described or referenced therein are non-limiting examples of materials that may be used in combination with the compounds disclosed herein, and one skilled in the art can readily review the literature to identify other materials that may be used in combination.

In the examples of material synthesis, all reactions were carried out under nitrogen unless otherwise stated. All reaction solvents were anhydrous and used as received from commercial sources. The synthesis product is subjected to structural validation and characterization using one or more equipment conventional in the art (including, but not limited to, bruker's nuclear magnetic resonance apparatus, shimadzu's liquid chromatograph-mass spectrometer, gas chromatograph-mass spectrometer, differential scanning calorimeter, shanghai prism-based fluorescence spectrophotometer, wuhan Corset's electrochemical workstation, anhui Beidek's sublimator, etc.) in a manner well known to those skilled in the art. In an embodiment of the device, the device characteristics are also tested using equipment conventional in the art (including, but not limited to, an evaporator manufactured by Anttrom engineering, an optical test system manufactured by Fushida, suzhou, an ellipsometer manufactured by Beijing Mass., etc.) in a manner well known to those skilled in the art. Since the relevant contents of the above-mentioned device usage, testing method, etc. are known to those skilled in the art, the inherent data of the sample can be obtained with certainty and without being affected, and therefore, the relevant contents are not described in detail in this patent.

Materials synthesis example:

the preparation method of the compound of the present invention is not limited, and the following compounds are typically but not limited to, and the synthetic route and the preparation method thereof are as follows:

synthesis example 1: synthesis of Compound 7

Step 1: synthesis of intermediate 7-1:

2-bromo-7-iodo-9, 9-dimethylfluorene (9 g,22.6 mmol), aniline (2.1g, 22.6 mmol), palladium acetate (51mg, 3 mmol), 4, 5-bis-diphenylphosphine-9, 9-dimethylxanthene (266mg, 3 mmol), sodium t-butoxide (4.4 g,45.2 mmol), toluene (200 mL) were added to a three-necked flask under nitrogen and reacted at 70 ℃ for 16h. After completion of the reaction, it was cooled to room temperature, diluted with water, and the mixture was extracted with ethyl acetate, the organic phase was washed with water, concentrated to remove the solvent, and purified by column chromatography (PE/DCM = 5/1) to obtain 7-1 (7 g, yield: 85%) as a white solid.

Step 2: synthesis of intermediate 7-2:

under the protection of nitrogen, 7-1 (7g, 19.28mmol), palladium acetate (2.1g, 9.6 mmol), potassium carbonate (2.6 g, 19.38mmol) and pivalic acid (50 mL) were put into a three-necked flask and reacted at 140 ℃ for 16 hours. Cooled to room temperature, diluted with water, the mixture was extracted with ethyl acetate, the organic phase was washed with water, and concentrated to remove the solvent, and purified by column chromatography (PE/DCM =2 1) to obtain 7-2 (2.5 g, yield: 66%) as a white solid.

And step 3: synthesis of intermediate 7-3:

7-2 (2.5g, 6.9mmol), sodium hydride (0.32g, 13.8mmol), 2-chloro-4-phenyl-quinazoline (2500mg, 10.38mmol) and N, N-dimethylformamide (130 mL) were put into a three-necked flask under nitrogen protection, and reacted at room temperature for 5 hours. After completion of the reaction, water was added to dilute, the mixture was extracted with dichloromethane, the organic phase was washed with water, concentrated to remove the solvent, and purified by column chromatography (PE/DCM = 3/1) to obtain 7-3 (3.5 g, yield: 58%) as a yellow solid.

And 4, step 4: synthesis of Compound 7

7-3 (3.5g, 6.2mmol), 7-5 (1.7 g, 6.2mmol), tris (dibenzylideneacetone) dipalladium (56mg, 0.062mmol), 2-dicyclohexylphosphine-2 ',6' -dimethoxybiphenyl (50mg, 0.124mmol), sodium tert-butoxide (1.2g, 12.4 mmol), xylene (80 mL) were charged into a three-necked flask and reacted at 120 ℃ for 16 hours under nitrogen atmosphere. After completion of the reaction, it was cooled to room temperature, diluted with water, the mixture was extracted with toluene, the organic phase was washed with water, concentrated to remove the solvent, and purified by column chromatography (PE/DCM = 5/1) as yellow solid compound 7 (2.1 g, yield: 42%). The product was identified as the target product, with a molecular weight of 806.

Device embodiment

Example 1

First, a glass substrate, having an Indium Tin Oxide (ITO) anode 80nm thick, was cleaned and then treated with oxygen plasma and UV ozone. After treatment, the substrate was dried in a glove box to remove moisture. The substrate is then mounted on a substrate support and loaded into a vacuum chamber. The organic layer specified below was in a vacuum of about 10 degrees ^-8 In the case of torr, the deposition was carried out by thermal vacuum deposition sequentially on an ITO anode at a rate of 0.2 to 2 angstrom/sec. Compound HI was used as Hole Injection Layer (HIL). The compound HT is used as a Hole Transport Layer (HTL). Compound EB was used as an Electron Blocking Layer (EBL). Then compound RD (2%) was doped in compound 7 of the present invention and co-evaporated to serve as the light emitting layer (EML). Compound HB was used as a Hole Blocking Layer (HBL). On the hole blocking layer, compound ET and 8-hydroxyquinoline-lithium (Liq) were co-evaporated as an Electron Transport Layer (ETL). Finally, 8-hydroxyquinoline-lithium (Liq) was evaporated to a thickness of 1nm as an electron injection layer, and 120nm of aluminum as a cathode. The device was then transferred back to the glove box and encapsulated with a glass lid and moisture absorber to complete the device.

Comparative example 1

Comparative example 1 was prepared in the same manner as in example 1 except that compound a was used instead of compound 7 of the present invention in the light-emitting layer (EML).

The detailed device portion layer structures and thicknesses are shown in the following table. Wherein more than one layer of the materials used is obtained by doping different compounds in the stated weight ratios.

TABLE 1 device Structure

The material structure used in the device is as follows:

table 2 shows the measured values at 1000cd/m ² Measured λ max, voltage (V) and CIE data.

TABLE 2 device data

Device ID	CIE(x,y)	λmax(nm)	Voltage(V)
				Example 1	0.685,0.314	626	2.92
Comparative example 1	0.683,0.317	625	4.92

Discussion:

example 1 and comparative example 1 each used compound 7 and compound a as host materials. As shown by the data in table 2, CIE, λ max is similar. The driving voltage of example 1 was 2.9V, and the driving voltage of comparative example 1 was 4.92V, and the driving voltage of example 1 was reduced by 40% compared to comparative example 1. Data show that the compound containing the structure of the formula 1 introduces nitrogen heterocycle with excellent electron transport capability on carbazole, introduces triarylamine with excellent hole transport capability on indene for substitution, constructs a bipolar compound, and enables the structure to simultaneously have excellent hole transport capability and electron transport capability, thereby obtaining low-voltage performance in devices.

It should be understood that the various embodiments described herein are illustrative only and are not intended to limit the scope of the invention. Thus, the invention as claimed may include variations from the specific embodiments and preferred embodiments described herein, as will be apparent to those skilled in the art. Many of the materials and structures described herein may be substituted with other materials and structures without departing from the spirit of the present invention. It should be understood that various theories as to why the invention works are not intended to be limiting.

Claims

1. A compound represented by formulae 2-8:

wherein, Y ₁ ，Y ₅ To Y ₈ Each independently selected from CR _y ；

L _y Is a single bond;

wherein X ₁ To X ₄ Each independently selected from CR _x1 ；X ₅ 、X ₈ Each independently selected from CR _x2 ；

Wherein L is _x Is a single bond;

wherein Z is ₁ To Z ₄ Each independently selected from C or CR _z Wherein Z is ₃ Is selected from C and L _x Connecting;

wherein each occurrence of Ar, the same or different, is selected from substituted or unsubstituted aryl groups having 6 to 30 carbon atoms;

wherein R is _x1 ，R _x2 ，R _y ，R _z And R is selected, identically or differently on each occurrence, from the group consisting of: hydrogen, deuterium, halogen, substituted or unsubstituted alkyl groups having 1 to 20 carbon atoms, substituted or unsubstituted cycloalkyl groups having 3 to 20 ring carbon atoms, substituted or unsubstituted aryl groups having 6 to 30 carbon atoms, substituted or unsubstituted heteroaryl groups having 3 to 30 carbon atoms, cyano groups, and combinations thereof.

2. The compound of claim 1, wherein Y ₁ ，Y ₅ To Y ₈ Each independently selected from CR _y Wherein R is _y Each occurrence, the same or different, is selected from the group consisting of: hydrogen, deuterium, substituted or unsubstituted compounds having 6 to 30 carbonsAn aryl group of atoms, a substituted or unsubstituted heteroaryl group having 3 to 30 carbon atoms, and combinations thereof.

3. The compound of claim 1, wherein X ₁ To X ₄ Each independently selected from CR _X1 ，X ₅ 、X ₈ Each independently selected from CR _X2 Wherein R is _x1 And R _x2 Each occurrence, the same or different, is selected from the group consisting of: hydrogen, deuterium, substituted or unsubstituted aryl groups having 6 to 30 carbon atoms, substituted or unsubstituted heteroaryl groups having 3 to 30 carbon atoms, and combinations thereof.

4. The compound of claim 1, wherein Z is ₁ To Z ₄ Middle Z ₃ Is selected from C and L _x Are linked and the others are each independently selected from CR _z Wherein R is _z Each occurrence, the same or different, is selected from the group consisting of: hydrogen, deuterium, substituted or unsubstituted aryl groups having 6 to 30 carbon atoms, substituted or unsubstituted heteroaryl groups having 3 to 30 carbon atoms, and combinations thereof.

5. The compound of claim 1, wherein Y is ₁ ，Y ₅ To Y ₈ Each independently selected from CR _y ；

X ₁ To X ₄ Each independently selected from CR _x1 ，X ₅ 、X ₈ Each independently selected from CR _x2 ；

Z ₁ To Z ₄ Middle Z ₃ Is selected from C and L _x Are linked and the others are each independently selected from CR _z ；

R _y ，R _x1 ，R _x2 And R _z The same or different at each occurrence is selected from the group consisting of: hydrogen, deuterium, substituted or unsubstituted aryl groups having 6 to 20 carbon atoms, substituted or unsubstituted heteroaryl groups having 3 to 20 carbon atoms, and combinations thereof.

6. The compound of claim 1, wherein R, identically or differently on each occurrence, is selected from the group consisting of substituted or unsubstituted alkyl groups having 1-20 carbon atoms, substituted or unsubstituted cycloalkyl groups having 3-20 ring carbon atoms, substituted or unsubstituted aryl groups having 6-30 carbon atoms, substituted or unsubstituted heteroaryl groups having 3-30 carbon atoms, and combinations thereof.

7. The compound of claim 1, wherein R, on each occurrence, is selected, identically or differently, from the group consisting of: methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, tert-butyl, phenyl, and combinations thereof.

8. The compound of claim 1, wherein each occurrence of Ar, the same or different, is selected from the group consisting of: substituted or unsubstituted phenyl, substituted or unsubstituted fluorenyl, and combinations thereof.

9. The compound of claim 1, wherein each occurrence of Ar, the same or different, is selected from the group consisting of: phenyl, biphenyl, cyanophenyl, fluorenyl, dimethylfluorenyl, diphenylfluorenyl, biphenyl, terphenyl, phenanthryl, triphenylene, spirobifluorenyl, and combinations thereof.

10. The compound of claim 1, wherein the compound is selected from the group consisting of:

11. an electroluminescent device, comprising:

an anode, a cathode, a anode and a cathode,

a cathode electrode, which is provided with a cathode,

and an organic layer disposed between the anode and the cathode, the organic layer comprising the compound of any one of claims 1-10.

12. The device of claim 11, wherein the organic layer is an emissive layer and the compound is a host material.

13. The device of claim 12, wherein the light emitting layer further comprises a phosphorescent light emitting material.

14. The device of claim 13, wherein the phosphorescent light emitting material is a metal complex comprising at least one ligand comprising the structure of any one of:

wherein the content of the first and second substances,

X _c And X _d Each independently selected from the group consisting of: o, S, se and NR _N2 ；

R _a ，R _b And R _c May represent mono-, poly-, or unsubstituted, and may be the same or different at each occurrence;

15. An electroluminescent device as claimed in claim 13 wherein the phosphorescent light emitting material is an Ir, pt or Os complex.

16. An electroluminescent device as claimed in claim 14 wherein the phosphorescent light-emitting material is an Ir complex having an Ir (L) _a )(L _b )(L _c ) In which L _a ，L _b And L _c Ligands, the same or different, selected from any of the above.

17. The electroluminescent device of claim 15, wherein said phosphorescent light-emitting material is selected from the group consisting of:

wherein X _f At each occurrenceThe same or different is selected from the group consisting of: o, S, se, NR _N3 And CR _C3 R _C4 ；

Wherein, X _e Selected from CR, identically or differently at each occurrence _d Or N;

R _a ，R _b ，R _c ，R _d ，R _N3 ，R _C3 and R _C4 Each occurrence, the same or different, is selected from the group consisting of: hydrogen, deuterium, halogen, a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms, a substituted or unsubstituted cycloalkyl group having 3 to 20 ring carbon atoms, a substituted or unsubstituted heteroalkyl group having 1 to 20 carbon atoms, a substituted or unsubstituted arylalkyl group having 7 to 30 carbon atoms, a substituted or unsubstituted alkoxy group having 1 to 20 carbon atoms, a substituted or unsubstituted aryloxy group having 6 to 30 carbon atoms, a substituted or unsubstituted alkenyl group having 2 to 20 carbon atoms, a substituted or unsubstituted aryl group having 6 to 30 carbon atoms, a substituted or unsubstituted heteroaryl group having 3 to 30 carbon atoms, a substituted or unsubstituted alkylsilyl group having 3 to 20 carbon atoms, a substituted or unsubstituted arylsilyl group having 6 to 20 carbon atoms, a substituted or unsubstituted amine group having 0 to 20 carbon atoms, an acyl group, a carbonyl group, a carboxylic acid group, an ester group, a nitrile, an isonitrile, a sulfur group, a sulfinyl group, a sulfonyl group, a phosphino group, and combinations thereof,

adjacent substituents can optionally be joined to form a ring.

18. A compound formulation comprising a compound of any one of claims 1-10.