CN116925062A

CN116925062A - Organic electroluminescent material and device thereof

Info

Publication number: CN116925062A
Application number: CN202210316291.XA
Authority: CN
Inventors: 王强; 王乐; 张子岩; 王美营; 邝志远; 夏传军
Original assignee: Beijing Summer Sprout Technology Co Ltd
Current assignee: Beijing Summer Sprout Technology Co Ltd
Priority date: 2022-03-29
Filing date: 2022-03-29
Publication date: 2023-10-24

Abstract

The invention discloses a novel organic electroluminescent material and a device thereof. The novel organic electroluminescent materials are compounds having the structure represented by formula 1, which are useful as host materials, electron transport materials and/or light extraction materials in organic electroluminescent devices, and which provide better device performance, in particular longer device lifetime and higher light extraction efficiency. Also disclosed are organic electroluminescent devices and compound compositions comprising the organic electroluminescent materials, and electronic devices comprising the electroluminescent devices.

Description

Organic electroluminescent material and device thereof

Technical Field

The present invention relates to a compound for an organic electronic device, such as an organic light emitting device. And more particularly, to a compound having the structure of formula 1, and an organic electroluminescent device and a compound composition including the same.

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 (OLEDs), organic photovoltaic devices (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 electroluminescent devices.

In 1987, tang and Van Slyke of Isomandah reported a double-layered 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). Once biased into the device, green light is emitted from the device. The invention lays a foundation for the development of modern Organic Light Emitting Diodes (OLEDs). Most advanced 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. Because OLEDs are self-illuminating solid state devices, they offer great potential for display and lighting applications. Furthermore, the inherent properties of organic materials, such as their flexibility, can make them well suited for particular applications, such as fabrication on flexible substrates.

OLEDs can be divided into three different types according to their light emission mechanism. The OLED of the Tang and van Slyke invention is a fluorescent OLED. It uses only singlet light emission. The triplet states generated in the device are wasted through non-radiative decay channels. Thus, the Internal Quantum Efficiency (IQE) of fluorescent OLEDs is only 25%. This limitation prevents commercialization of OLEDs. In 1997, forrest and Thompson reported phosphorescent OLEDs using triplet emission from heavy metals containing complexes as emitters. Thus, both singlet and triplet states can be harvested, achieving a 100% IQE. Because of its high efficiency, the discovery and development of phosphorescent OLEDs has contributed directly to the commercialization of Active Matrix OLEDs (AMOLEDs). Recently, adachi achieved high efficiency by Thermally Activated Delayed Fluorescence (TADF) of organic compounds. These emitters have a small singlet-triplet gap, making it possible for the excitons to return from the triplet state to the singlet state. In TADF devices, triplet excitons can generate singlet excitons by reverse intersystem crossing, resulting in high IQE.

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

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

The emission color of an OLED can be achieved by the structural design of the luminescent material. The OLED may include a light emitting layer or layers to achieve a desired spectrum. Green, yellow and red OLEDs, phosphorescent materials have been successfully commercialized. Blue phosphorescent devices still have problems of blue unsaturation, short device lifetime, high operating voltage, and the like. Commercial full color OLED displays typically employ a mixing strategy using blue fluorescent and phosphorescent yellow, or red and green. Currently, a rapid decrease in efficiency of phosphorescent OLEDs at high brightness remains a problem. In addition, it is desirable to have a more saturated emission spectrum, higher efficiency and longer device lifetime.

Currently, the OLED display technology has been applied in the fields of smart phones, tablet computers and the like, and further will expand to the large-size application fields of televisions and the like. However, due to the difference of refractive indexes, light emitted by the light emitting layer of the OLED at certain angles is totally reflected at the interface of the ITO thin film and the glass substrate and the interface of the glass substrate and air, which results in that light emitted to the external space of the OLED device is only about 20% of the total amount of light emitted, and the remaining about 80% of the light is limited inside the device mainly in the form of guided waves, so that the light emitting efficiency of the conventional OLED device is low (about 20%), and the development and application of the OLED are greatly restricted by the large gap between the external quantum efficiency and the internal quantum efficiency of the OLED. Therefore, how to improve the light extraction efficiency of an OLED has become a research hotspot, i.e. how to reduce the total reflection effect in an OLED device and to improve the ratio of light coupling out to the external space of the device (light extraction efficiency ) has attracted a lot of attention.

One of the effective ways to improve the light extraction efficiency of an OLED device is to add a light extraction layer (also called a capping layer, CPL) structure to the device structure by using a light extraction material with a high refractive index, and when the CPL is formed by using a light extraction material with a suitable refractive index, the total reflection effect inside the device can be effectively reduced and the light transmittance is increased due to the higher refractive index of the CPL, so that the light extraction efficiency is improved.

CN110684021a discloses a benzoxazole derivative having heteroaryl group, which has the following general structureCompounds in which triazine building blocks are bonded to dibenzofurans having specific substituents and their analogous structures are not disclosed and taught.

WO2020009519A1 discloses a compound having the general structureWherein Ar is ₃ With->A structure, n is selected from 2 toAn integer between 5. It follows that compounds in which the triazine group is linked to at least 2 benzoxazoles and similar building blocks via a linking structure are of interest, and specifically the following structures are disclosed:However, there is no disclosure or teaching of compounds in which a triazine group is linked to benzoxazoles and the like and dibenzofurans and the like having specific substitutions via a linking structure.

Besides light extraction materials, host materials are also a class of materials that have an important impact on the overall performance of electroluminescent devices, and CN112920179A discloses a compound useful as a host material in electroluminescent devices having the following general structureAnd specifically discloses a compound in which a triazine structural unit and a benzoxazole and the like are bonded to both left and right sides of a dibenzofuran group, respectively, but it does not disclose and teach a compound in which specifically substituted dibenzofuran and benzoxazole and the like are bonded to both left and right sides of a triazine structural unit, respectively.

However, there is still room for further improvement in the various host materials or light extraction materials reported so far, and further research and development of new materials are still needed to meet the increasingly improved demands of the industry, especially for higher device efficiency, longer device lifetime, and lower driving voltage.

Disclosure of Invention

The present invention aims to solve at least part of the above problems by providing a series of novel compounds having the structure of formula 1. The compounds are useful as host materials, electron transport materials, and/or light extraction materials in organic electroluminescent devices, and these novel compounds provide better device performance, particularly longer device lifetime and/or higher light extraction efficiency.

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

wherein Ar is ₂ Selected from the structures represented by formula 2 or formula 3:

Z ₁ selected from O, S, CR 'R ", se or SiR' R";

Z ₂ is selected from CR, identically or differently at each occurrence _x Or N; and at least two Z ₂ Selected from N;

Z ₃ selected from O or Se;

Z ₄ selected from O, S or Se;

X ₁ to X ₉ Is selected identically or differently on each occurrence from C, CR _x Or N, and wherein X ₁ To X ₈ At least two of which are selected from C and are respectively with the L ₁ And the Ar is as described ₃ Connected to at least one X ₉ Selected from C and with said L ₃ Are connected;

X ₁₀ is selected from CR, identically or differently at each occurrence _x Or N;

L ₁ and L ₃ Each occurrence is identically or differently selected from a single bond, a substituted or unsubstituted arylene group having 6 to 30 carbon atoms, a substituted or unsubstituted heteroarylene group having 3 to 30 carbon atoms, or a combination thereof;

L ₂ selected from a single bond, phenylene, naphthylene, pyridylene, pyrimidinylene, biphenylene, phenanthrylene, terphenylene, or a combination thereof;

Ar ₃ each occurrence, identically or differently, represents mono-or poly-substitution;

Ar ₃ and is selected identically or differently on each occurrence from the group consisting of: substituted or unsubstituted aryl groups having 6 to 30 carbon atoms, substituted or unsubstituted aryl groups having 3 to 30 carbon atomsHeteroaryl groups of atoms and combinations thereof;

Ar ₁ ，Ar ₄ ，R _x r 'and R' are, for each occurrence, identically or differently selected 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 heterocyclyl having 3 to 20 ring 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 groups having from 6 to 30 carbon atoms, substituted or unsubstituted heteroaryl groups having from 3 to 30 carbon atoms, substituted or unsubstituted alkylsilyl groups having from 3 to 20 carbon atoms, substituted or unsubstituted alkylgermanium groups having from 3 to 20 carbon atoms, substituted or unsubstituted arylgermanium groups having from 6 to 20 carbon atoms, substituted or unsubstituted amino groups having from 0 to 20 carbon atoms, acyl groups, carbonyl groups, carboxylic acid groups, ester groups, cyano groups, isocyano groups, hydroxyl groups, mercapto groups, sulfinyl groups, sulfonyl groups, phosphino groups, and combinations thereof;

Wherein adjacent substituents R _x Can optionally be linked to form a ring.

According to another embodiment of the present invention, there is also disclosed an electroluminescent device comprising a cathode, an anode, and an organic layer comprising a compound having the structure of formula 1, the specific structure of the compound being as shown in the previous embodiment.

According to another embodiment of the present invention, there is also disclosed a compound composition comprising the compound having the structure of formula 1, the specific structure of the compound being as shown in the previous embodiment.

According to another embodiment of the present invention, an electronic device is also disclosed, which includes an electroluminescent device, and the specific structure of the electroluminescent device is as shown in the foregoing embodiment.

The novel compound with the structure shown in the formula 1 can be used as a main body material, an electron transport material and/or a light extraction material in an electroluminescent device. These novel compounds can provide better device performance, especially longer lifetime and/or higher light extraction efficiency.

Drawings

Fig. 1 is a schematic diagram of an organic light emitting device that may contain the compounds and compound compositions disclosed herein.

Fig. 2 is a schematic view of another organic light emitting device that may contain the compounds and compound compositions disclosed herein.

FIG. 3 is a graph of refractive index of compound A-1, compound A-6, compound C, compound D and compound E at different wavelengths.

Detailed Description

OLEDs can be fabricated on a variety of substrates, such as glass, plastic, and metal. Fig. 1 schematically illustrates, without limitation, an organic light-emitting device 100. The drawings are not necessarily to scale, and some of the layer structures in the drawings 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, a light emitting 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 layers described. The nature and function of the layers and exemplary materials are described in more detail in U.S. patent US7,279,704B2, columns 6-10, the entire contents of which are incorporated herein by reference.

There are more instances of each of these layers. For example, a flexible and transparent substrate-anode combination is disclosed in U.S. patent 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 in a 50:1 molar ratio ₄ m-MTDATA of TCNQ as disclosed in U.S. patent application publication No. 2003/0230980, which is incorporated by reference in its entirety. Examples of host materials are disclosed in U.S. Pat. No. 6,303,238 to Thompson et al, which is incorporated by reference in its entirety. Examples of n-doped electron transport layers are those described as 1:1 in molar ratio with Li as disclosed in U.S. patent application publication No. 2003/0230980, which is incorporated by reference in its entirety. Examples of cathodes are disclosed in U.S. Pat. nos. 5,703,436 and 5,707,745, which are incorporated by reference in their entirety, including composite cathodes having a thin layer of metal, such as Mg: ag, with an overlying transparent, electrically 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 protective layers 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 by way of non-limiting example. The function of the OLED may be achieved by combining the various layers described above, or some of the 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 sublayers. 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, such as the organic light emitting device 200 shown schematically and without limitation in fig. 2, which differs from fig. 1 in that an encapsulation layer 102 may also be included over the cathode 190 to prevent 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 an organic-inorganic hybrid layer. The encapsulation layer should be placed directly or indirectly outside the OLED device. Multilayer film packages are described in U.S. patent US7,968,146B2, the entire contents of which are incorporated herein by reference.

The OLED may also further comprise a light extraction layer, which may be provided on the surface of the OLED substrate, or any other suitable location, such as between the substrate and the ITO layer, between the organic layer and the cathode layer, between the cathode and the encapsulation layer, or on top of the encapsulation layer, etc.

Devices manufactured according to embodiments of the present invention may be incorporated into a variety of 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, heads-up displays, displays that are fully or partially transparent, flexible displays, smart phones, tablet computers, tablet phones, wearable devices, smart watches, laptop computers, digital cameras, camcorders, viewfinders, micro-displays, 3-D displays, vehicle displays, and taillights.

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

As used herein, "top" means furthest from the substrate and "bottom" means closest to the substrate. In the case where the first layer is described as being "disposed" on the second layer, "the first layer is disposed farther from the substrate. Unless a first layer is "in contact with" a second layer, other layers may be present between the first and second layers. For example, a cathode may be described as "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 "photosensitive" when it is believed that the ligand directly contributes to the photosensitive properties of the emissive material. When it is believed that the ligand does not contribute to the photosensitive properties of the emissive material, the ligand may be referred to as "ancillary," but ancillary ligands may alter the properties of the photosensitive ligand.

It is believed that the Internal Quantum Efficiency (IQE) of fluorescent OLEDs can be limited by spin statistics that delay fluorescence by more than 25%. Delayed fluorescence can be generally classified into two types, i.e., P-type delayed fluorescence and E-type delayed fluorescence. The P-type delayed fluorescence is generated by triplet-triplet annihilation (TTA).

On the other hand, the E-type delayed fluorescence does not depend on the collision of two triplet states, but on the transition between the triplet states and the singlet excited state. Compounds capable of generating E-type delayed fluorescence are required to have very small mono-triplet gaps in order for the transition between the energy states. The thermal energy may activate a transition from the triplet state back to the singlet state. This type of delayed fluorescence is also known as Thermally Activated Delayed Fluorescence (TADF). A significant feature of TADF is that the delay component increases with increasing temperature. The fraction of backfill singlet excited states may reach 75% if the reverse intersystem crossing (RISC) rate is fast enough to minimize non-radiative decay from the triplet states. The total singlet fraction may be 100%, well in excess of 25% of the spin statistics of the electrically generated excitons.

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

Definition of terms for substituents

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

Alkyl-as used herein, includes straight and branched chain alkyl groups. The alkyl group may be an alkyl group having 1 to 20 carbon atoms, preferably an alkyl group having 1 to 12 carbon atoms, more preferably an alkyl group having 1 to 6 carbon atoms. 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. Among the above, methyl, ethyl, propyl, isopropyl, n-butyl, sec-butyl, isobutyl, tert-butyl, n-pentyl, neopentyl and n-hexyl are preferred. In addition, the alkyl group may be optionally substituted.

Cycloalkyl-as used herein, includes cyclic alkyl. Cycloalkyl groups may be cycloalkyl groups having 3 to 20 ring carbon atoms, preferably 4 to 10 carbon atoms. Examples of cycloalkyl groups include cyclobutyl, cyclopentyl, cyclohexyl, 4-methylcyclohexyl, 4-dimethylcyclohexyl, 1-adamantyl, 2-adamantyl, 1-norbornyl, 2-norbornyl and the like. Among the above, cyclopentyl, cyclohexyl, 4-methylcyclohexyl, 4-dimethylcyclohexyl are preferred. In addition, cycloalkyl groups may be optionally substituted.

Heteroalkyl-as used herein, a heteroalkyl comprises an alkyl chain in which one or more carbons is replaced by a heteroatom selected from the group consisting of nitrogen, oxygen, sulfur, selenium, phosphorus, silicon, germanium, and boron. The heteroalkyl group may be a heteroalkyl group having 1 to 20 carbon atoms, preferably a heteroalkyl group having 1 to 10 carbon atoms, more preferably a heteroalkyl group having 1 to 6 carbon atoms. Examples of heteroalkyl groups include methoxymethyl, ethoxymethyl, ethoxyethyl, methylthiomethyl, ethylthiomethyl, ethylthioethyl, methoxymethoxymethyl, ethoxymethoxymethyl, ethoxyethoxyethyl, hydroxymethyl, hydroxyethyl, hydroxypropyl, mercaptomethyl, mercaptoethyl, mercaptopropyl, aminomethyl, aminoethyl, aminopropyl, dimethylaminomethyl, trimethylgermylmethyl, trimethylgermylethyl, dimethylethylgermylmethyl, dimethylisopropylgermylmethyl, t-butyldimethylgermylmethyl, triethylgermylmethyl, triethylgermylethyl, triisopropylgermylmethyl, triisopropylgermylethyl, trimethylsilylmethyl, trimethylsilylethyl, trimethylsilylisopropyl, triisopropylsilylmethyl. In addition, heteroalkyl groups may be optionally substituted.

Alkenyl-as used herein, covers straight chain, branched chain, and cyclic alkylene groups. Alkenyl groups may be alkenyl groups containing 2 to 20 carbon atoms, preferably alkenyl groups having 2 to 10 carbon atoms. Examples of alkenyl groups include ethenyl, propenyl, 1-butenyl, 2-butenyl, 3-butenyl, 1, 3-butadienyl, 1-methylvinyl, styryl, 2-diphenylvinyl, 1-methallyl, 1-dimethylallyl, 2-methallyl, 1-phenylallyl, 2-phenylallyl, 3-diphenylallyl, 1, 2-dimethylallyl, 1-phenyl-1-butenyl, 3-phenyl-1-butenyl, cyclopentenyl, cyclopentadienyl, cyclohexenyl, cycloheptenyl, cycloheptatrienyl, cyclooctenyl, cyclooctatetraenyl and norbornenyl. In addition, alkenyl groups may be optionally substituted.

Alkynyl-as used herein, straight chain alkynyl is contemplated. The alkynyl group may be an alkynyl group containing 2 to 20 carbon atoms, preferably an alkynyl group having 2 to 10 carbon atoms. Examples of alkynyl groups include ethynyl, propynyl, propargyl, 1-butynyl, 2-butynyl, 3-butynyl, 1-pentynyl, 2-pentynyl, 3-dimethyl-1-butynyl, 3-ethyl-3-methyl-1-pentynyl, 3-diisopropyl-1-pentynyl, phenylethynyl, phenylpropynyl and the like. Among the above, preferred are ethynyl, propynyl, propargyl, 1-butynyl, 2-butynyl, 3-butynyl, 1-pentynyl and phenylethynyl. In addition, alkynyl groups may be optionally substituted.

Aryl or aromatic-as used herein, non-fused and fused systems are contemplated. The aryl group may be an aryl group having 6 to 30 carbon atoms, preferably an aryl group having 6 to 20 carbon atoms, more preferably an aryl group having 6 to 12 carbon atoms. Examples of the aryl group include phenyl, biphenyl, terphenyl, triphenylene, tetraphenylene, naphthalene, anthracene, phenalene, phenanthrene, fluorene, pyrene,perylene and azulene, preferably phenyl, biphenyl, terphenyl, triphenylene, fluorene and naphthalene. Examples of non-condensed aryl groups include phenyl, biphenyl-2-yl, biphenyl-3-yl, biphenyl-4-yl, p-terphenyl-3-yl, p-terphenyl-2-yl, m-terphenyl-4-yl, m-terphenyl-3-yl, m-terphenyl-2-yl, o-tolyl, m-tolyl, p- (2-phenylpropyl) phenyl, 4 '-methylbiphenyl, 4' -tert-butyl-p-terphenyl-4-yl, o-cumyl, m-cumyl, p-cumyl, 2, 3-xylyl, 3, 4-xylyl, 2, 5-xylyl, mesityl and m-tetrabiphenyl. In addition, aryl groups may be optionally substituted.

Heterocyclyl or heterocycle-as used herein, non-aromatic cyclic groups are contemplated. The non-aromatic heterocyclic group includes a saturated heterocyclic group having 3 to 20 ring atoms and an unsaturated non-aromatic heterocyclic group having 3 to 20 ring atoms, wherein at least one ring atom is selected from the group consisting of nitrogen atom, oxygen atom, sulfur atom, selenium atom, silicon atom, phosphorus atom, germanium atom and boron atom, and the preferred non-aromatic heterocyclic group is one having 3 to 7 ring atoms including at least one hetero atom such as nitrogen, oxygen, silicon or sulfur. Examples of non-aromatic heterocyclic groups include oxiranyl, oxetanyl, tetrahydrofuranyl, tetrahydropyranyl, dioxanyl, aziridinyl, dihydropyrrolyl, tetrahydropyrrolyl, piperidinyl, oxazolidinyl, morpholinyl, piperazinyl, oxacycloheptatrienyl, thietaneyl, azepanyl and tetrahydrosilol. In addition, the heterocyclic group may be optionally substituted.

Heteroaryl-as used herein, non-fused and fused heteroaromatic groups that may contain 1 to 5 heteroatoms, wherein at least one heteroatom is selected from the group consisting of nitrogen atoms, oxygen atoms, sulfur atoms, selenium atoms, silicon atoms, phosphorus atoms, germanium atoms, and boron atoms. Heteroaryl also refers to heteroaryl. The heteroaryl group may be a heteroaryl group having 3 to 30 carbon atoms, preferably a heteroaryl group having 3 to 20 carbon atoms, more preferably a heteroaryl group having 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, oxazole, dioxazole, thiadiazole, pyridine, pyridazine, pyrimidine, pyrazine, triazine, oxazine, oxathiazine, oxadiazine, indole, benzimidazole, indazole, indenazine, benzoxazole, benzisoxazole, benzothiazole, quinoline, isoquinoline, cinnoline, quinazoline, quinoxaline, naphthyridine, phthalazine, pteridine, xanthene, acridine, phenazine, phenothiazine, benzofuranpyridine, furodipyridine, benzothiophene, thienodipyridine, benzoselenophene, selenodipyridine, preferably dibenzothiophene, dibenzofuran, dibenzoselenophene, carbazole, indolocarbazole, imidazole, pyridine, triazine, benzimidazole, 1, 2-aza, 1-aza-3-borane, 1-borane, 4-boron, and the like. In addition, heteroaryl groups may be optionally substituted.

Alkoxy-as used herein, is represented by-O-alkyl, -O-cycloalkyl, -O-heteroalkyl, or-O-heterocyclyl. Examples and preferred examples of the alkyl group, the cycloalkyl group, the heteroalkyl group and the heterocyclic group are the same as those described above. The alkoxy group may be an alkoxy group having 1 to 20 carbon atoms, preferably an alkoxy group having 1 to 6 carbon atoms. Examples of alkoxy groups include methoxy, ethoxy, propoxy, butoxy, pentoxy, hexyloxy, cyclopropyloxy, cyclobutyloxy, cyclopentyloxy, cyclohexyloxy, tetrahydrofuranyloxy, tetrahydropyranyloxy, methoxypropyloxy, ethoxyethyloxy, methoxymethyloxy and ethoxymethyloxy. In addition, the alkoxy group may be optionally substituted.

Aryloxy-as used herein, is represented by-O-aryl or-O-heteroaryl. Examples and preferred examples of aryl and heteroaryl groups are the same as described above. The aryloxy group may be an aryloxy group having 6 to 30 carbon atoms, preferably an aryloxy group having 6 to 20 carbon atoms. Examples of aryloxy groups include phenoxy and biphenoxy. In addition, the aryloxy group may be optionally substituted.

Aralkyl-as used herein, encompasses aryl-substituted alkyl. The aralkyl group may be an aralkyl group having 7 to 30 carbon atoms, preferably an aralkyl group having 7 to 20 carbon atoms, more preferably an aralkyl group having 7 to 13 carbon atoms. Examples of aralkyl groups include benzyl, 1-phenylethyl, 2-phenylethyl, 1-phenylisopropyl, 2-phenylisopropyl, phenyl tert-butyl, α -naphthylmethyl, 1- α -naphthyl-ethyl, 2- α -naphthylethyl, 1- α -naphthylisopropyl, 2- α -naphthylisopropyl, β -naphthylmethyl, 1- β -naphthyl-ethyl, 2- β -naphthyl-ethyl, 1- β -naphthylisopropyl, 2- β -naphthylisopropyl, p-methylbenzyl, m-methylbenzyl, o-methylbenzyl, p-chlorobenzyl, m-chlorobenzyl, o-chlorobenzyl, p-bromobenzyl, m-bromobenzyl, o-bromobenzyl, p-iodobenzyl, m-iodobenzyl, o-iodobenzyl, p-hydroxybenzyl, m-hydroxybenzyl, o-aminobenzyl, m-aminobenzyl, o-aminobenzyl, p-nitrobenzyl, m-nitrobenzyl, o-nitrobenzyl, p-cyanobenzyl, m-cyanobenzyl, cyano, o-cyanobenzyl, o-chlorobenzyl, 1-chlorophenyl and 1-isopropyl. Among the above, preferred are benzyl, p-cyanobenzyl, m-cyanobenzyl, o-cyanobenzyl, 1-phenylethyl, 2-phenylethyl, 1-phenylisopropyl and 2-phenylisopropyl. In addition, aralkyl groups may be optionally substituted.

Alkyl-as used herein, alkyl-substituted silicon groups are contemplated. The silyl group may be a silyl group having 3 to 20 carbon atoms, preferably a silyl group having 3 to 10 carbon atoms. Examples of the alkyl silicon group include trimethyl silicon group, triethyl silicon group, methyldiethyl silicon group, ethyldimethyl silicon group, tripropyl silicon group, tributyl silicon group, triisopropyl silicon group, methyldiisopropyl silicon group, dimethylisopropyl silicon group, tri-t-butyl silicon group, triisobutyl silicon group, dimethyl-t-butyl silicon group, and methyldi-t-butyl silicon group. In addition, the alkyl silicon group may be optionally substituted.

Arylsilane-as used herein, encompasses at least one aryl-substituted silicon group. The arylsilane group may be an arylsilane group having 6 to 30 carbon atoms, preferably an arylsilane group having 8 to 20 carbon atoms. Examples of arylsilyl groups include triphenylsilyl, phenyldiphenylsilyl, diphenylbiphenyl silyl, phenyldiethylsilyl, diphenylethylsilyl, phenyldimethylsilyl, diphenylmethylsilyl, phenyldiisopropylsilyl, diphenylisopropylsilyl, diphenylbutylsilyl, diphenylisobutylsilyl, diphenyltert-butylsilyl. In addition, arylsilane groups may be optionally substituted.

Alkyl germanium group-as used herein, alkyl substituted germanium groups are contemplated. The alkylgermanium group may be an alkylgermanium group having 3 to 20 carbon atoms, preferably an alkylgermanium group having 3 to 10 carbon atoms. Examples of alkyl germanium groups include trimethyl germanium group, triethyl germanium group, methyl diethyl germanium group, ethyl dimethyl germanium group, tripropyl germanium group, tributyl germanium group, triisopropyl germanium group, methyl diisopropyl germanium group, dimethyl isopropyl germanium group, tri-t-butyl germanium group, triisobutyl germanium group, dimethyl-t-butyl germanium group, methyl-di-t-butyl germanium group. In addition, alkyl germanium groups may be optionally substituted.

Arylgermanium group-as used herein, encompasses at least one aryl or heteroaryl substituted germanium group. The arylgermanium group may be an arylgermanium group having 6-30 carbon atoms, preferably an arylgermanium group having 8 to 20 carbon atoms. Examples of aryl germanium groups include triphenyl germanium group, phenyl biphenyl germanium group, diphenyl biphenyl germanium group, phenyl diethyl germanium group, diphenyl ethyl germanium group, phenyl dimethyl germanium group, diphenyl methyl germanium group, phenyl diisopropyl germanium group, diphenyl isopropyl germanium group, diphenyl butyl germanium group, diphenyl isobutyl germanium group, diphenyl tert-butyl germanium group. In addition, the arylgermanium group may be optionally substituted.

The term "aza" in azadibenzofurans, azadibenzothiophenes and the like means that one or more C-H groups in the corresponding aromatic fragment are replaced by a nitrogen atom. For example, azatriphenylenes include dibenzo [ f, h ] quinoxalines, dibenzo [ f, h ] quinolines, and other analogs having two or more nitrogens in the ring system. Other nitrogen analogs of the above-described aza derivatives will be readily apparent to those of ordinary skill in the art, and all such analogs are intended to be included in the terms described herein.

In the present disclosure, when any one of the terms from the group consisting of: substituted alkyl, substituted cycloalkyl, substituted heteroalkyl, substituted heterocyclyl, substituted aralkyl, substituted alkoxy, substituted aryloxy, substituted alkenyl, substituted alkynyl, substituted aryl, substituted heteroaryl, substituted alkylsilyl, substituted arylsilyl, substituted alkylgermanium, substituted arylgermanium, substituted amino, substituted acyl, substituted carbonyl, substituted carboxylic acid, substituted ester, substituted sulfinyl, substituted sulfonyl, substituted phosphino, alkyl, cycloalkyl, heteroalkyl, heterocyclyl, aralkyl, alkoxy, aryloxy, alkenyl, alkynyl, aryl, heteroaryl, alkylsilyl, arylsilyl, amino, acyl, carbonyl, carboxylic acid, ester, sulfinyl, sulfonyl and phosphino groups, any one or more of which may be selected from the group consisting of deuterium, unsubstituted alkyl having 1 to 20 carbon atoms, unsubstituted cycloalkyl having 3 to 20 ring carbon atoms, unsubstituted cycloalkyl having 1 to 20 carbon atoms, unsubstituted alkenyl having 3 to 20 carbon atoms, unsubstituted aryl having 3 to 20 carbon atoms, unsubstituted alkenyl having 3 to 30 carbon atoms, unsubstituted arylsilane groups having from 6 to 20 carbon atoms, unsubstituted alkylgermanium groups having from 3 to 20 carbon atoms, unsubstituted arylgermanium groups having from 6 to 20 carbon atoms, unsubstituted amino groups having from 0 to 20 carbon atoms, acyl groups, carbonyl groups, carboxylic acid groups, ester groups, cyano groups, isocyano groups, hydroxyl groups, mercapto groups, sulfinyl groups, sulfonyl groups, phosphine groups, and combinations thereof.

It will be appreciated that when a fragment of a molecule is described as a substituent or otherwise attached to another moiety, its name may be written according to whether it is a fragment (e.g., phenyl, phenylene, naphthyl, dibenzofuranyl) or according to 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 equivalent.

In the compounds mentioned in this disclosure, the hydrogen atoms 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 syntropes in the compound may be preferred because of their enhanced efficiency and stability of the device.

In the compounds mentioned in this disclosure, polysubstituted means inclusive of disubstituted up to the maximum available substitution range. When a substituent in a compound mentioned in this disclosure means multiple substitution (including di-substitution, tri-substitution, tetra-substitution, etc.), it means that the substituent may be present at a plurality of available substitution positions on its linking structure, and the substituent present at each of the plurality of available substitution positions may be of the same structure or of different structures.

In the compounds mentioned in this disclosure, adjacent substituents in the compounds cannot be linked to form a ring unless explicitly defined, for example, adjacent substituents can optionally be linked to form a ring. In the compounds mentioned in this disclosure, adjacent substituents can optionally be linked to form a ring, both in the case where adjacent substituents can be linked to form a ring and in the case where adjacent substituents are not linked to form a ring. Where adjacent substituents can optionally be joined to form a ring, the ring formed can be monocyclic or polycyclic (including spiro, bridged, fused, etc.), as well as alicyclic, heteroalicyclic, aromatic or heteroaromatic. 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 further distant carbon atoms. Preferably, adjacent substituents refer to substituents bonded to the same carbon atom and 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 be taken 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:

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

furthermore, the expression that adjacent substituents can optionally be linked to form a ring is also intended to be taken to mean that, in the case where one of the adjacent two substituents represents hydrogen, the second substituent is bonded at the position to which the hydrogen atom is bonded, thereby forming a ring. This is illustrated by the following formula:

Z ₁ selected from O, S, CR 'R ", se or SiR' R";

Z ₃ selected from O or Se;

Z ₄ selected from O, S or Se;

X ₁ to X ₉ Is selected identically or differently on each occurrence from C, CR _x Or N; and wherein X is ₁ To X ₈ At least two of which are selected from C and are respectively with the L ₁ And the Ar is as described ₃ Connected to at least one X ₉ Selected from C and with said L ₃ Are connected;

Ar ₃ and is selected identically or differently on each occurrence from the group consisting of: substituted or unsubstituted aryl groups having from 6 to 30 carbon atoms, substituted or unsubstituted heteroaryl groups having from 3 to 30 carbon atoms, and combinations thereof;

Ar ₁ ，Ar ₄ ，R _x r 'and R' are, for each occurrence, identically or differently selected 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 alkyl having 3 to 20 ring carbon atoms A heterocyclic group of a ring atom, a substituted or unsubstituted aralkyl group of 7 to 30 carbon atoms, a substituted or unsubstituted alkoxy group of 1 to 20 carbon atoms, a substituted or unsubstituted aryloxy group of 6 to 30 carbon atoms, a substituted or unsubstituted alkenyl group of 2 to 20 carbon atoms, a substituted or unsubstituted aryl group of 6 to 30 carbon atoms, a substituted or unsubstituted heteroaryl group of 3 to 30 carbon atoms, a substituted or unsubstituted alkylsilyl group of 3 to 20 carbon atoms, a substituted or unsubstituted arylsilyl group of 6 to 20 carbon atoms, a substituted or unsubstituted alkylgermanium group of 3 to 20 carbon atoms, a substituted or unsubstituted arylgermanium group of 6 to 20 carbon atoms, a substituted or unsubstituted amino group of 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 hydroxyl group, a mercapto group, a sulfinyl group, a sulfonyl group, a phosphino group, and combinations thereof;

wherein adjacent R _x May optionally be linked to form a ring.

In this context, the term "a" is used herein,represents the Ar ₂ The connection position with formula 1.

Herein, "adjacent substituent R _x Can optionally be linked to form a ring "is intended to mean wherein adjacent substituents R _x Can optionally be linked to form a ring. Obviously, none of these adjacent groups of substituents may be linked to form a ring.

According to one embodiment of the invention, wherein Ar ₁ And Ar is a group ₂ Each occurrence may be the same or different.

According to one embodiment of the present invention, wherein the compound has a structure represented by formula 4, formula 5, formula 6, or formula 7:

Z ₁ selected from O, S, CR 'R ", se or SiR' R";

Z ₃ selected from O or Se;

Z ₄ selected from O, S or Se;

X ₁ to X ₉ Is selected identically or differently on each occurrence from C, CR _x Or N, and wherein X ₁ To X ₈ At least 1 of them is selected from C and is identical to Ar ₃ Connected to at least one X ₉ Selected from C and with said L ₃ Are connected;

Ar ₁ ，Ar ₄ ，R _x R 'and R' are, for each occurrence, identically or differently selected 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 heterocyclyl having 3 to 20 ring atoms, substituted or unsubstituted aralkyl having 7 to 30 carbon atoms, substituted or unsubstituted aralkyl having 1 to 20 carbon atomsAlkoxy having from 6 to 30 carbon atoms, substituted or unsubstituted aryloxy having from 2 to 20 carbon atoms, substituted or unsubstituted alkenyl having from 6 to 30 carbon atoms, substituted or unsubstituted aryl having from 3 to 30 carbon atoms, substituted or unsubstituted heteroaryl having from 3 to 30 carbon atoms, substituted or unsubstituted alkylsilyl having from 3 to 20 carbon atoms, substituted or unsubstituted arylsilyl having from 6 to 20 carbon atoms, substituted or unsubstituted alkylgermanium having from 3 to 20 carbon atoms, substituted or unsubstituted arylgermanium having from 6 to 20 carbon atoms, substituted or unsubstituted amino having from 0 to 20 carbon atoms, acyl, carbonyl, carboxylic acid, ester, cyano, isocyano, hydroxyl, mercapto, sulfinyl, sulfonyl, phosphino, and combinations thereof;

Wherein adjacent substituents R _x Can optionally be linked to form a ring.

According to one embodiment of the invention, wherein Z ₂ Selected from N.

According to one embodiment of the invention, wherein Z ₁ Selected from O, S or Se.

According to one embodiment of the invention, wherein Z ₁ Selected from O or S.

According to one embodiment of the invention, wherein Z ₃ And Z ₄ Selected from O.

According to one embodiment of the invention, wherein X ₁ To X ₉ Is selected identically or differently on each occurrence from C or CR _x ，X ₁₀ Is selected from CR, identically or differently at each occurrence _x 。

According to one embodiment of the invention, wherein R _x And 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 alkenyl groups having 2 to 20 carbon atoms, 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 invention, wherein R _x And is selected identically or differently on each occurrence from the group consisting of: hydrogen, deuterium, halogen, phenyl, pyridyl, vinyl, naphthyl, biphenyl, phenanthryl, triphenylene, dibenzofuranyl, dibenzothienyl, and combinations thereof.

According to one embodiment of the invention, wherein Ar ₁ And is selected identically or differently on each occurrence from the group consisting of: substituted or unsubstituted alkyl groups having from 1 to 20 carbon atoms, substituted or unsubstituted cycloalkyl groups having from 3 to 20 ring carbon atoms, substituted or unsubstituted aryl groups having from 6 to 30 carbon atoms, substituted or unsubstituted heteroaryl groups having from 3 to 30 carbon atoms, substituted or unsubstituted amino groups having from 0 to 20 carbon atoms, and combinations thereof.

According to one embodiment of the invention, wherein Ar ₁ And is selected identically or differently on each occurrence from the group consisting of: substituted or unsubstituted aryl groups having from 6 to 20 carbon atoms, substituted or unsubstituted heteroaryl groups having from 3 to 20 carbon atoms, substituted or unsubstituted amino groups having from 0 to 20 carbon atoms, and combinations thereof.

According to one embodiment of the invention, wherein Ar ₁ And is selected identically or differently on each occurrence from the group consisting of: phenyl, pyridyl, naphthyl, biphenyl, phenanthryl, terphenyl, triphenylene, dibenzofuranyl, dibenzothienyl, benzoxazolyl, benzothiazolyl,a group, a carbazolyl group, and combinations thereof.

According to one embodiment of the invention, wherein Ar ₃ And Ar is a group ₄ And is selected identically or differently on each occurrence from the group consisting of: substituted or unsubstituted aryl groups having from 6 to 30 carbon atoms, substituted or unsubstituted heteroaryl groups having from 3 to 30 carbon atoms, and combinations thereof.

According to one embodiment of the invention, wherein Ar ₃ And Ar is a group ₄ And is selected identically or differently on each occurrence from substituted or unsubstituted aryl groups having from 6 to 20 carbon atoms.

According to one embodiment of the invention, wherein Ar ₃ And Ar is a group ₄ And is selected identically or differently on each occurrence from the group consisting of: phenyl, naphthyl, biphenyl, phenanthryl, terphenyl, triphenylene, and combinations thereof.

According to one embodiment of the invention, wherein L ₁ And L ₃ And is selected identically or differently on each occurrence from a single bond, or a substituted or unsubstituted arylene group having 6 to 30 carbon atoms.

According to one embodiment of the invention, wherein L ₁ And L ₃ And is selected identically or differently on each occurrence from the group consisting of: single bonds, phenylene, naphthylene, biphenylene, phenanthrylene, and combinations thereof.

According to an embodiment of the invention, wherein the compound is selected from the group consisting of compound a-1 to compound a-440, wherein the specific structure of the compound a-1 to compound a-440 is as defined in claim 11.

According to one embodiment of the invention, wherein the hydrogen energy in the structures of compounds a-1 to a-440 is partially or completely replaced by deuterium.

According to an embodiment of the present invention, there is also disclosed an electroluminescent device including an organic layer including a compound having the structure of formula 1, the specific structure of the compound being as shown in any one of the foregoing embodiments.

According to one embodiment of the invention, wherein in the electroluminescent device the organic layer is a light emitting layer, an electron transporting layer and/or a light extracting layer.

According to one embodiment of the invention, wherein in the electroluminescent device the organic layer is a light emitting layer between a cathode and an anode, the compound is a host material.

According to one embodiment of the invention, wherein in the electroluminescent device the organic layer is a light extraction layer located over the cathode, the compound is a light extraction material.

According to one embodiment of the invention, wherein in the organic electroluminescent device, the organic layer is a light emitting layer comprising at least one phosphorescent light emitting material.

According to one embodiment of the invention, wherein the phosphorescent material is a metal complex having M (L _a ) _m (L _b ) _n (L _c ) _q Is of the general formula (I);

m is selected from metals with a relative atomic mass greater than 40;

L _a 、L _b 、L _c a first ligand, a second ligand and a third ligand coordinated to the M; l (L) _a 、L _b 、L _c Can optionally be linked to form a multidentate ligand;

L _a 、L _b 、L _c may be the same or different; m is 1, 2 or 3; n is 0, 1 or 2; q is 0, 1 or 2; the sum of M, n, q is equal to the oxidation state of M; when m is greater than or equal to 2, a plurality of L _a May be the same or different; when n is 2, two L _b May be the same or different; when q is 2, two L _c May be the same or different;

L _a has a structure as shown in formula 8:

wherein,,

ring D is selected from a 5 membered heteroaryl ring or a 6 membered heteroaryl ring;

ring E is selected from a 5 membered unsaturated carbocycle, a benzene ring, a 5 membered heteroaromatic ring or a 6 membered heteroaromatic ring;

ring D and ring E via U _a And U _b Condensing;

U _a and U _b Selected identically or differently on each occurrence from C or N;

R _d ，R _e each occurrence, identically or differently, represents mono-substituted, poly-substituted or unsubstituted;

V ₁ -V ₄ is selected from CR, identically or differently at each occurrence _v Or N;

R _d ，R _e ，R _v and 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 heteroaryl having 3 to 20 carbon atoms, substituted or unsubstituted heterocyclyl having 3 to 20 ring 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 alkylsilyl having 3 to 20 carbon atoms, substituted or unsubstituted alkylgermanium having 6 to 20 carbon atoms, substituted or unsubstituted aryl having 6 to 20 carbon atoms, substituted or unsubstituted germanium having 0 to 20 carbon atoms, carbonyl, cyano, sulfonyl, and combinations thereof;

Adjacent substituents R _d ，R _e ，R _v Can optionally be linked to form a ring;

L _b 、L _c each occurrence is identically or differently selected from any one of the following structures:

wherein,,

R _a ，R _b and R is _c Each occurrence, identically or differently, represents mono-substituted, poly-substituted, or unsubstituted;

X _b and is selected identically or differently on each occurrence from the group consisting of: o, S, se, NR _N1 And CR (CR) _C1 R _C2 ；

X _c And X _d Is selected identically or differently on each occurrence from the group consisting ofThe group consisting of: o, S, se and NR _N2 ；

R _a ，R _b ，R _c ，R _N1 ，R _N2 ，R _C1 And R is _C2 And 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 heterocyclyl having 3 to 20 ring 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 alkylsilyl having 3 to 20 carbon atoms, substituted or unsubstituted alkylgermanium having 6 to 20 carbon atoms, substituted or unsubstituted aryl having 6 to 20 carbon atoms, substituted or unsubstituted arylgermanium having 6 to 20 carbon atoms, substituted or unsubstituted aryl having 6 to 20 carbon atoms, substituted or unsubstituted germanium having 0 to 20 carbon atoms, carbonyl, cyano, sulfonyl, and combinations thereof;

The ligand L _b 、L _c In the structure of (a), adjacent substituent R _a ，R _b ，R _c ，R _N1 ，R _N2 ，R _C1 And R is _C2 Can optionally be linked to form a ring.

Herein, adjacent substituents R _d ，R _e ，R _v Can optionally be linked to form a ring, intended to mean that when a substituent R is present _d R is substituent R _e R is substituent R _v In which adjacent substituents, e.g. adjacent substituents R _d Between and adjacent substituents R _e Between and adjacent substituents R _v Between and adjacent substituents R _d And R is R _e Between and adjacent substituents R _d And R is R _v Between and adjacent substituents R _e And R is R _v Any one or more of these adjacent substituent groups can be linked to form a ring. Obviously, when substituents R are present _d R is substituent R _e R is substituent R _v In this case, none of the substituents may be bonded to form a ring.

Herein, adjacent substituents R _a ，R _b ，R _c ，R _N1 ，R _N2 ，R _C1 And R is _C2 Can optionally be linked to form a ring, intended to mean groups of substituents adjacent thereto, e.g. two substituents R _a Between two substituents R _b Between two substituents R _c Between, substituent R _a And R is _b Between, substituent R _a And R is _c Between, substituent R _b And R is _c Between, substituent R _a And R is _N1 Between, substituent R _b And R is _N1 Between, substituent R _a And R is _C1 Between, substituent R _a And R is _C2 Between, substituent R _b And R is _C1 Between, substituent R _b And R is _C2 Between, substituent R _a And R is _N2 Between, substituent R _b And R is _N2 Between, and R _C1 And R is _C2 In between, any one or more of these substituent groups may be linked to form a ring. Obviously, these substituents may not all be linked to form a ring.

According to one embodiment of the present invention, wherein, in formula 8, R _d 、R _e 、R _v At least one or two groups of adjacent substituents are linked to form a ring. For example, two substituents R _d Joined to form a ring, or two substituents R _e Joined to form a ring, or two substituents R _v Joined to form a ring, or substituent R _d And substituent R _e Forms a ring, or substituent R _d And substituent R _v Forms a ring, or substituent R _e And substituent R _v Is connected with each other to form a ring, or two substituents R _d Two substituents R simultaneously linked to form a ring _e Joined to form a ring, or two substituents R _d Two substituents R simultaneously linked to form a ring _v Joined to form a ring, or two substituents R _e Two substituents R simultaneously linked to form a ring _v Are linked to form a ring, substituent R _e And substituent R _v Simultaneously 2 substituents R linked to form a ring _v Joined to form a ring, or substituent R _d And substituent R _v Simultaneously 2 substituents R linked to form a ring _v The connection forms a ring; r is R _d 、R _e 、R _v Similar situation is true when more groups of adjacent substituents are joined to form a ring.

According to one embodiment of the invention, the electroluminescent device wherein the phosphorescent material is a metal complex having M (L _a ) _m (L _b ) _n Is of the general formula (I);

m is selected from metals with a relative atomic mass greater than 40;

L _a 、L _b a first ligand and a second ligand coordinated to the M, respectively; l (L) _a 、L _b Can optionally be linked to form a multidentate ligand;

m is 1, 2 or 3; n is 0, 1 or 2; the sum of M and n is equal to the oxidation state of M; when m is greater than or equal to 2, a plurality of L _a May be the same or different; when n is 2, two L _b May be the same or different;

L _a has a structure as shown in formula 8:

wherein,,

ring D and ring E via U _a And U _b Condensing;

wherein the ligand L _b The structure is as follows:

wherein R is ₁ To R ₇ Each independently selected from the group consisting of: hydrogen, deuterium, halogen, substituted or unsubstituted alkyl having 1-20 carbon atoms, substituted or unsubstitutedCycloalkyl having 3 to 20 ring carbon atoms, substituted or unsubstituted heteroalkyl having 1 to 20 carbon atoms, substituted or unsubstituted heterocyclyl having 3 to 20 ring atoms, substituted or unsubstituted aryl alkyl 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 alkylsilyl having 3 to 20 carbon atoms, substituted or unsubstituted aryl silyl having 6 to 20 carbon atoms, substituted or unsubstituted alkylgermyl having 3 to 20 carbon atoms, substituted or unsubstituted arylgermyl having 6 to 20 carbon atoms, substituted or unsubstituted amino having 0 to 20 carbon atoms, acyl, carbonyl, carboxylate, cyano, sulfide, sulfonyl, and combinations thereof.

According to one embodiment of the invention, the electroluminescent device wherein the ligand L _b The structure is as follows:

wherein R is ₁ -R ₃ At least one selected from the group consisting of 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 heteroalkyl groups having 1 to 20 carbon atoms, or combinations thereof; and/or R ₄ -R ₆ At least one of which is selected from the group consisting of 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 heteroalkyl groups having 1 to 20 carbon atoms, or combinations thereof.

wherein R is ₁ -R ₃ At least two of which are, identically or differently, selected from the group consisting of substituted or unsubstituted alkyl groups having from 1 to 20 carbon atoms, substituted or unsubstituted cycloalkyl groups having from 3 to 20 ring carbon atoms, substituted or unsubstituted heteroalkyl groups having from 1 to 20 carbon atoms, or combinations thereof; and/or R ₄ -R ₆ At least two of which are, identically or differently, selected from the group consisting of substituted or unsubstituted alkyl groups having from 1 to 20 carbon atoms, substituted or unsubstituted cycloalkyl groups having from 3 to 20 ring carbon atoms, substituted or unsubstituted heteroalkyl groups having from 1 to 20 carbon atoms, or combinations thereof.

wherein R is ₁ -R ₃ At least two of which are, identically or differently, selected from the group consisting of substituted or unsubstituted alkyl groups having from 2 to 20 carbon atoms, substituted or unsubstituted cycloalkyl groups having from 3 to 20 ring carbon atoms, substituted or unsubstituted heteroalkyl groups having from 2 to 20 carbon atoms, or combinations thereof; and/or R ₄ -R ₆ At least two of which are, identically or differently, selected from the group consisting of substituted or unsubstituted alkyl groups having from 2 to 20 carbon atoms, substituted or unsubstituted cycloalkyl groups having from 3 to 20 ring carbon atoms, substituted or unsubstituted heteroalkyl groups having from 2 to 20 carbon atoms, or combinations thereof.

According to one embodiment of the invention, the electroluminescent device wherein the phosphorescent material is an Ir complex, a Pt complex or an Os complex.

According to one embodiment of the invention, the electroluminescent device wherein the phosphorescent material is an Ir complex and has Ir (L _a )(L _b )(L _c )、Ir(L _a ) ₂ (L _b )、Ir(L _a )(L _b ) ₂ 、Ir(L _a ) ₂ (L _c ) Or Ir (L) _a )(L _c ) ₂ Any of the structures shown.

According to one embodiment of the invention, wherein L _a Has a structure as shown in formula 8 and comprises at least one structural unit selected from the group consisting of a 6-membered and 6-membered aromatic ring, a 6-membered and 6-membered heteroaromatic ring, a 6-membered and 5-membered aromatic ring and a 6-membered and 5-membered heteroaromatic ring.

According to one embodiment of the invention, the electroluminescent device, wherein L _a Has a structure as shown in formula 8 and comprises at least one structural unit selected from the group consisting of naphthalene, phenanthrene, quinoline, isoquinoline and azaphenanthrene.

According to one embodiment of the invention, the phosphorescent material is an Ir complex and comprises a ligand L in the electroluminescent device _a The L is _a And is selected from any one of the group consisting of the following structures, identically or differently, at each occurrence:

according to one embodiment of the invention, wherein in the electroluminescent device the phosphorescent material is an Ir complex and comprises a ligand L _b The L is _b And is selected from any one of the group consisting of the following structures, identically or differently, at each occurrence:

according to one embodiment of the invention, wherein in the electroluminescent device, the phosphorescent light-emitting material is selected from the group consisting of:

according to another embodiment of the present invention, there is also disclosed a compound composition comprising a compound having a structure represented by formula 1, the specific structure of the compound being as shown in any one of the preceding embodiments.

According to another embodiment of the present invention, an electronic device is also disclosed, which includes an electroluminescent device, and the specific structure of the electroluminescent device is as shown in any one of the foregoing embodiments.

Combined with other materials

The materials described herein for specific 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 2016/0359122A1, paragraphs 0132-0161, the entire contents of which are incorporated herein by reference. The materials described or mentioned 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.

Materials described herein as useful for specific layers in an organic light emitting device may be used in combination with a variety of other materials present in the device. For example, the compounds disclosed herein may be used in combination with a variety of luminescent dopants, hosts, transport layers, blocking layers, injection layers, electrodes, and other layers that may be present. Combinations of these materials are described in detail in U.S. patent application Ser. No. 2015/0349273A1, paragraphs 0080-0101, the entire contents of which are incorporated herein by reference. The materials described or mentioned 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 protection, unless otherwise indicated. All reaction solvents were anhydrous and used as received from commercial sources. The synthetic products were subjected to structural confirmation and characterization testing using one or more equipment conventional in the art (including, but not limited to, bruker's nuclear magnetic resonance apparatus, shimadzu's liquid chromatograph, liquid chromatograph-mass spectrometer, gas chromatograph-mass spectrometer, differential scanning calorimeter, shanghai's optical technique fluorescence spectrophotometer, wuhan Koste's electrochemical workstation, anhui Bei Yi g 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, a vapor deposition machine manufactured by Angstrom Engineering, an optical test system manufactured by Frieda, st. John's, an ellipsometer manufactured by Beijing, etc.), in a manner well known to those skilled in the art. Since those skilled in the art are aware of the relevant contents of the device usage and the testing method, and can obtain the intrinsic data of the sample certainly and uninfluenced, the relevant contents are not further described in this patent.

Material synthesis examples:

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

synthesis example 1: synthesis of Compound A-1

Step 1: synthesis of intermediate 3

Intermediate 1 (10.0 g,36.6 mmol), intermediate 2 (13.9 g,54.7 mmol), [1,1' -bis (diphenylphosphino) ferrocene ] palladium (II) dichloride (1.3 g,1.8 mmol), potassium acetate (7.0 g,73.0 mmol), 1, 4-dioxane (200 mL) were charged to a three-necked flask under nitrogen and reacted at 110℃for 16h. After the reaction was completed, cooled to room temperature, filtered, the filtrate was extracted with ethyl acetate, the organic phase was washed with water, and the solvent was removed by concentration, and the crude product was purified by column chromatography (PE/ea=5:1) to give intermediate 3 (10.0 g, yield: 85%) as a white solid.

Step 2: synthesis of intermediate 5

Intermediate 3 (18.5 g,57.6 mmol), intermediate 4 (13.0 g,57.6 mmol), tetrakis (triphenylphosphine) palladium (1.4 g,1.2 mmol), sodium carbonate (15.8 g,115.0 mmol), tetrahydrofuran (160 mL), water (40 mL) were added under nitrogen to a three-necked flask and reacted at 60℃for 16h. After the reaction was completed, cooled to room temperature, filtered, the filtrate was extracted with ethyl acetate, the organic phase was washed with water, and the solvent was concentrated to remove the solvent, and the crude product was purified by column chromatography (PE/dcm=1:2) to give intermediate 5 (16.0 g, yield: 72%) as a white solid.

Step 3: synthesis of Compound A-1

Intermediate 5 (5.0 g,13.0 mmol), intermediate 6 (4.8 g,13.0 mmol), tetrakis (triphenylphosphine) palladium (230.0 mg,0.2 mmol), potassium carbonate (5.6 g,40.4 mmol), toluene (160 mL), ethanol (40 mL), water (40 mL) were added under nitrogen to a three-necked flask and reacted at 100℃for 16h. After the reaction was completed, cooled to room temperature, distilled water was added, the mixture was extracted with ethyl acetate, the organic phase was washed with water, and the solvent was concentrated to remove the solvent, and the crude product was purified by column chromatography (PE/dcm=10:1) to give compound a-1 (5.0 g, yield: 65%) as a white solid. The product was identified as the target product and had a molecular weight of 592.2.

Synthesis example 2: synthesis of Compound A-6

Step 1: synthesis of intermediate 8

Intermediate 7 (10.0 g,36.6 mmol), intermediate 2 (14.0 g,54.9 mmol), [1,1' -bis (diphenylphosphino) ferrocene ] palladium (II) dichloride (1.3 g,1.8 mmol), potassium acetate (7.2 g,73.2 mmol), 1, 4-dioxane (200 mL) were added to a three-necked flask under nitrogen and reacted at 110℃for 16h. After the reaction was completed, cooled to room temperature, filtered, the filtrate was extracted with ethyl acetate, the organic phase was washed with water, and the solvent was removed by concentration, and the crude product was purified by column chromatography (PE/ea=5:1) to give intermediate 8 (9.0 g, yield: 77%) as a white solid.

Step 2: synthesis of intermediate 9

Intermediate 8 (7.0 g,21.8 mmol), intermediate 4 (4.9 g,21.8 mmol), tetrakis (triphenylphosphine) palladium (1.4 g,1.2 mmol), sodium carbonate (6.06 g,43.6 mmol), tetrahydrofuran (160 mL), water (40 mL) were added to a three-necked flask under nitrogen and reacted at 60℃for 16h. After the reaction was completed, cooled to room temperature, filtered, the filtrate was extracted with ethyl acetate, the organic phase was washed with water, and the solvent was concentrated to remove the solvent, and the crude product was purified by column chromatography (PE/dcm=1:2) to give intermediate 9 (7.0 g, yield: 83%) as a white solid.

Step 3: synthesis of Compound A-6

Intermediate 9 (2.0 g,5.22 mmol), intermediate 6 (2.1 g,5.7 mmol), tetrakis (triphenylphosphine) palladium (660 mg,0.57 mmol), potassium carbonate (1.57 g,11.4 mmol), toluene (80 mL), ethanol (20 mL), water (20 mL) were added to a three-necked flask under nitrogen atmosphere and reacted at 100℃for 12h. After the reaction was completed, a large amount of solid was precipitated, cooled to room temperature, and the solid was obtained by filtration, washed with water and ethanol three times, and the crude product was recrystallized from toluene to obtain white solid compound A-6 (2.0 g, yield: 65%). The product was identified as the target product and had a molecular weight of 592.2.

Those skilled in the art will recognize that the above preparation method is only an illustrative example, and that those skilled in the art can obtain other compound structures of the present invention by modifying it.

Device example 1

First, a glass substrate having an 80nm thick Indium Tin Oxide (ITO) anode was cleaned, and then treated with UV ozone and oxygen plasma. After the treatment, the substrate was baked in a glove box filled with nitrogen gas to remove moisture, and then mounted on a substrate holder and loaded into a vacuum chamber. The organic layer specified below was at a vacuum level of about 10 ^-8 In the case of TorrIs evaporated on the ITO anode in sequence by thermal vacuum. Co-evaporation of Compound HT and Compound HI was used as hole injection layer (HIL,/-)>). The compound HT is used as hole transport layer (HTL, -/-A)>). Compound EB is used as electron blocking layer (EBL, -/-for)>). Then co-evaporating the compound A-1 according to the invention as a first host and the compound B as a second host and the compound RD as a dopant to give a light-emitting layer (EML, (-) for example>). Use of Compound HB as hole blocking layer (HBL, -/->). On the hole blocking layer, a compound ET and 8-hydroxyquinoline-lithium (Liq) were co-evaporated as electron transport layer (ETL,/l)>). Finally, vapor deposition->8-hydroxyquinoline-lithium (Liq) with thickness as Electron Injection Layer (EIL) and vapor plating +.>Is used as a cathode. The device was then transferred back to the glove box and packaged with a glass lid to complete the device.

Device example 2

Device example 2 was prepared in the same manner as device example 1 except that the compound A-6 of the present invention was used in place of the compound A-1 of the present invention in the light-emitting layer (EML) as the first host.

Device comparative example 1

Device comparative example 1 was prepared in the same manner as device example 1 except that compound C was used as the first host instead of the compound a-1 of the present invention in the light-emitting layer (EML).

Device comparative example 2

Device comparative example 2 was prepared in the same manner as device example 1 except that compound D was used as the first host instead of the compound a-1 of the present invention in the light-emitting layer (EML).

Device comparative example 3

Device comparative example 3 was prepared in the same manner as device example 1 except that compound E was used as the first host instead of the compound A-1 of the present invention in the light-emitting layer (EML).

The detailed device layer structure and thickness are shown in the following table. Wherein more than one layer of the material used is doped with different compounds in the weight proportions described.

TABLE 1 device architectures of examples 1-2 and comparative examples 1-3

The material structure used in the device is as follows:

table 2 shows the results at 80mA/cm ² Maximum emission wavelength (lambda) of device examples and device comparative examples measured under constant current conditions _max ) And device lifetime (LT 97), wherein device lifetime (LT 97) refers to the time required for the device brightness to decay to 97% of its original brightness.

TABLE 2 device data for examples 1-2 and comparative examples 1-3

Device ID	λ _max (nm)	LT97[h]
			Example 1	619	155
Example 2	619	173
			Comparative example 1	619	134
Comparative example 2	619	138
			Comparative example 3	619	80

Discussion:

as can be seen from the data in table 2, the maximum emission wavelengths of the device examples and the device comparative examples remain the same; in terms of lifetime, the LT97 of example 1 was 155 hours, which was 21 hours longer than the LT97 of device comparative example 1, by 15.7%; LT97 of device example 2 was prolonged by 35h to 25.4% over 173 hours compared to LT97 of device comparative example 2. From the above data, it is clear that the compound of the present invention having a structure of formula 1, having a specific substituent on dibenzofuran, has unexpectedly improved device lifetime as compared with the comparative examples, compound C and compound D, respectively, since the specific substituent is introduced on dibenzofuran, it is shown that the compound of the present invention having a structure of formula 1 can make electron transport in the device more stable, and thus has a longer lifetime, and device performance is significantly improved.

Further, the device performance of example 2 using the compound A-6 of the present invention having the structure of formula 1 and comparative example 3 using the comparative compound E having the benzothiazole structural unit were further compared, and as is apparent from the data in Table 2, the device performance of example 2 was unexpectedly improved by 116% in terms of lifetime as compared with comparative example 3. This shows that the compound of the present invention having the structure of formula 1 can make electron transport in the device more stable, provide longer lifetime for the device, and make the device performance significantly improved.

After verifying the excellent properties of the compounds of the present invention as host materials in OLED devices, we have surprisingly found that the compounds of the present invention also have extremely high refractive indices through intensive studies.

Refractive indices of the related compounds were measured using ellipsometers.

Refractive index measurement method: clean silicon wafers were attached to the glass surface, then UV treated, mounted on a substrate support and placed into a vacuum chamber. At a vacuum level of about 10 ^-6 In the case of TorrThe compound to be tested is evaporated on a silicon wafer to form a film with the thickness of +.>Is a film of (a). Refractive index curves of the compounds (as shown in fig. 3) were obtained from films prepared by ellipsometry measurements produced by beijing mass topology, and refractive index data of the compounds a-1, a-6, C, D and E at specific wavelengths were recorded and shown in table 3.

TABLE 3 refractive index data for inventive and comparative compounds at specific wavelengths

Numbering of compounds	Refractive index @450nm	Refractive index @520nm	Refractive index @620nm
				Compound A-1	2.12	2.07	2.03
Compound A-6	2.10	2.06	2.04
				Compound C	1.93	1.87	1.83
Compound D	1.94	1.89	1.84
				Compound E	1.86	1.84	1.81

As is clear from the data in FIG. 3 and Table 3, the refractive index of the compounds A-1 and A-6 of the present invention having a specific substituent on dibenzofuran having the structure of formula 1 is greatly improved as compared with that of the compound C and the compound D of the comparative example, because the specific structural design of the compounds of the present invention introduces the specific substituent on the dibenzofuran fragment in the molecular structure. Compared with the comparative compound C, the refractive index of the compound A-1 is obviously improved in a blue light region (450 nm), a green light region (520 nm) and a red light region (620 nm), and especially the improvement amplitude in the red light region (620 nm) is 11%. The refractive index of the compound A-6 of the present invention is also improved at different wavelengths compared with that of the comparative compound D. Furthermore, the refractive index of the inventive compound A-6 comprising a benzoxazole structural unit having the structure of formula 1 also achieved an unexpectedly significant increase, in particular an increase of up to 12.7% in the red region (620 nm), compared to the comparative compound E comprising a benzothiazole structural unit.

It is known from the principle of optical absorption and refraction that the higher the refractive index is, the better the light extraction efficiency is. The compound of the invention with higher refractive index is selected as a light extraction layer (namely, a cover layer and CPL) in the organic electroluminescent device, so that the light extraction efficiency of the device can be improved more effectively. This conclusion is further verified by the following device examples.

Device example 3

First, a glass substrate is cleaned, which has a patterned anode structure: ITO (indium tin oxide)/Ag/ITO( ) Then treated with UV ozone and oxygen plasma. After the treatment, the substrate was baked in a glove box filled with nitrogen gas to remove moisture, and then mounted on a substrate holder and loaded into a vacuum chamber. The organic layer specified below was at a vacuum level of about 10 ^-8 In case of Torr +.>Is evaporated on the ITO anode in sequence by thermal vacuum. Co-evaporation of Compounds HT1 and HI as hole injection layer (HIL,/-A)>) The compound HT1 is used as hole transport layer (HTL,/or the like)>). Compound EB ₂ Is used as an electron blocking layer (EBL, < >>). Then co-evaporation of compound RH-1 and compound RD as dopant was used as light emitting layer (EML, ">). On the light-emitting layer, compound ET ₂ And 8-hydroxyquinoline-lithium co-evaporation as electron transport layer (ETL,/- >). Vapor deposition->Yb of thickness as Electron Injection Layer (EIL), followed by co-evaporation of magnesium and silver as cathode +.>Wherein the weight ratio of magnesium to silver is 1:9. Finally, the compound a-1 according to the invention is evaporated as a light extraction layer (CPL,) And encapsulated with a glass cover to complete the device.

TABLE 4 device structure of example 3

The structure of the materials newly used in the device is as follows:

table 5 shows the results at 10mA/cm ² Maximum emission wavelength (lambda) of device example 3 measured under constant current conditions _max ) Current Efficiency (CE), voltage (Voltage), power Efficiency (PE), external Quantum Efficiency (EQE), and Full Width Half Maximum (FWHM).

TABLE 5 device data for example 3

Device ID	λ _max (nm)	CE[cd/A]	Voltage(V)	PE(lm/W)	EQE(％)	FWHM[nm]
							Example 3	617	72.3	3.13	72.5	47.75	27.0

As is clear from the data in table 5, when the compound a-1 of the present invention having a high refractive index was used as CPL (light extraction layer) of a top emission device, device example 3 exhibited not only a very low voltage (3.13V), an extremely narrow full width at half maximum (27.0 nm) and high current efficiency (72.3 cd/a) and power efficiency (72.5 lm/W), but also achieved a high external quantum efficiency of 47.75%. This shows that device example 3 using the compounds of the present invention as light extraction materials has excellent overall performance. This also demonstrates that the compounds of the present invention represented by formula 1 can also be used as an excellent light extraction material for organic electroluminescent devices, and excellent device integration properties can be obtained.

From the above results, it can be seen that the compound with the structure of formula 1 disclosed by the invention can be used as a main material to prolong the service life of a device and can be used as a light extraction material to improve the light extraction efficiency of the device, so that the compound has wide commercial development prospect and application value.

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

Claims

1. A compound having a structure represented by formula 1:

Z ₁ selected from O, S, CR 'R ", se or SiR' R";

Z ₃ selected from O or Se;

Z ₄ selected from O, S or Se;

Ar ₁ ，Ar ₄ ，R _x r 'and R' are, for each occurrence, identically or differently selected from the group consisting of: hydrogen, deuterium, halogen, substituted or unsubstituted, having 1-20 carbonsAn alkyl group having 3 to 20 carbon atoms, a substituted or unsubstituted cycloalkyl group having 1 to 20 carbon atoms, a substituted or unsubstituted heteroalkyl group having 3 to 20 carbon atoms, a substituted or unsubstituted heterocyclic group having 7 to 30 carbon atoms, a substituted or unsubstituted aralkyl 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, substituted or unsubstituted heteroaryl groups having 3 to 30 carbon atoms, substituted or unsubstituted alkyl silicon groups having 3 to 20 carbon atoms, substituted or unsubstituted aryl silicon groups having 6 to 20 carbon atoms, substituted or unsubstituted alkyl germanium groups having 3 to 20 carbon atoms, substituted or unsubstituted aryl germanium groups having 6 to 20 carbon atoms, substituted or unsubstituted amino groups having 0 to 20 carbon atoms, acyl groups, carbonyl groups, carboxylic acid groups, ester groups, cyano groups, isocyano groups, hydroxyl groups, mercapto groups, sulfinyl groups, sulfonyl groups, phosphine groups, and combinations thereof;

Wherein adjacent substituents R _x Can optionally be linked to form a ring.

2. The compound of claim 1, wherein the compound has a structure represented by formula 4, formula 5, formula 6, or formula 7:

Z ₁ selected from O, S, CR 'R ", se or SiR' R";

Z ₃ selected from O or Se;

Z ₄ selected from O, S or Se;

Ar ₁ ，Ar ₄ ，R _x R 'and R' are, for each occurrence, identically or differently selected 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 heterocyclyl having 3 to 20 ring 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 alkylsilyl having 3 to 20 carbon atoms, substituted or unsubstituted alkylsilyl having 6 to 20 carbon atoms, substituted or unsubstituted alkylgermanium having 3 to 20 carbon atoms, and the likeSubstituted or unsubstituted arylgermanium groups having from 6 to 20 carbon atoms, substituted or unsubstituted amino groups having from 0 to 20 carbon atoms, acyl groups, carbonyl groups, carboxylic acid groups, ester groups, cyano groups, isocyano groups, hydroxyl groups, mercapto groups, sulfinyl groups, sulfonyl groups, phosphino groups, and combinations thereof;

Wherein adjacent substituents R _x Can optionally be linked to form a ring.

3. The compound of claim 1, wherein Z ₂ Selected from N.

4. The compound of claim 1 or 2, wherein Z ₁ Selected from O, S or Se; preferably Z ₁ Selected from O or S.

5. The compound of claim 1 or 2, wherein Z ₃ And Z ₄ Selected from O.

6. The compound of claim 1 or 2, wherein X ₁ To X ₉ Is selected identically or differently on each occurrence from C or CR _x ，X ₁₀ Is selected from CR, identically or differently at each occurrence _x 。

7. The compound of claim 1 or 6, wherein R _x And 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 alkenyl groups having 2 to 20 carbon atoms, 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;

preferably, R _x And is selected identically or differently on each occurrence from the group consisting of: hydrogen, deuterium, halogen, phenyl, pyridyl, vinyl, naphthyl, biphenyl, phenanthryl, triphenylene, dibenzofuranyl, dibenzothienyl, and combinations thereof.

8. A compound according to claim 1 or 2, wherein Ar ₁ And is selected identically or differently on each occurrence from the group consisting of: substituted or unsubstituted alkyl groups having from 1 to 20 carbon atoms, substituted or unsubstituted cycloalkyl groups having from 3 to 20 ring carbon atoms, substituted or unsubstituted aryl groups having from 6 to 30 carbon atoms, substituted or unsubstituted heteroaryl groups having from 3 to 30 carbon atoms, substituted or unsubstituted amino groups having from 0 to 20 carbon atoms, and combinations thereof;

preferably Ar ₁ And is selected identically or differently on each occurrence from the group consisting of: substituted or unsubstituted aryl groups having from 6 to 20 carbon atoms, substituted or unsubstituted heteroaryl groups having from 3 to 20 carbon atoms, substituted or unsubstituted amino groups having from 0 to 20 carbon atoms, and combinations thereof;

more preferably Ar ₁ And is selected identically or differently on each occurrence from the group consisting of: phenyl, pyridyl, naphthyl, biphenyl, phenanthryl, terphenyl, triphenylene, dibenzofuranyl, dibenzothienyl, benzoxazolyl, benzothiazolyl,a group, a carbazolyl group, and combinations thereof.

9. A compound according to claim 1 or 2, wherein Ar ₃ And Ar is a group ₄ And is selected identically or differently on each occurrence from the group consisting of: substituted or unsubstituted aryl groups having from 6 to 30 carbon atoms, substituted or unsubstituted heteroaryl groups having from 3 to 30 carbon atoms, and combinations thereof;

Preferably Ar ₃ And Ar is a group ₄ The same or different at each occurrence is selected from substituted or unsubstituted aryl groups having 6 to 20 carbon atoms;

more preferably Ar ₃ And Ar is a group ₄ And is selected identically or differently on each occurrence from the group consisting of: phenyl, naphthyl, biphenyl, phenanthryl, terphenyl, triphenylene, and combinations thereof.

10. The compound of claim 1 or 2, wherein L ₁ And L ₃ Each occurrence is identically or differently selected from a single bond, or a substituted or unsubstituted arylene group having 6 to 30 carbon atoms;

preferably L ₁ And L ₃ And is selected identically or differently on each occurrence from the group consisting of: single bonds, phenylene, naphthylene, biphenylene, phenanthrylene, and combinations thereof.

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

optionally, the hydrogen energy in the structures of compounds a-1 to a-440 can be partially or fully substituted with deuterium.

12. An electroluminescent device comprising a cathode, an anode and an organic layer comprising the compound of any one of claims 1 to 11.

13. The device of claim 12, wherein the organic layer is a light emitting layer, an electron transporting layer, and/or a light extraction layer.

14. The device of claim 13, wherein the organic layer is a light emitting layer and the compound is a host material.

15. The device of claim 14, wherein the organic layer is a light emitting layer comprising at least one phosphorescent light emitting material.

16. The device of claim 15, wherein the phosphorescent material is a metal complex having M (L _a ) _m (L _b ) _n (L _c ) _q Is of the general formula (I);

m is selected from metals with a relative atomic mass greater than 40;

L _a has a structure as shown in formula 8:

wherein,,

ring D and ring E via U _a And U _b Condensing;

R _d ，R _e ，R _v and 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 heterocyclyl having 3 to 20 ring 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 groups having from 6 to 30 carbon atoms, substituted or unsubstituted heteroaryl groups having from 3 to 30 carbon atoms, substituted or unsubstituted alkylsilyl groups having from 3 to 20 carbon atoms, substituted or unsubstituted alkylgermanium groups having from 3 to 20 carbon atoms, substituted or unsubstituted arylgermanium groups having from 6 to 20 carbon atoms, substituted or unsubstituted amino groups having from 0 to 20 carbon atoms, acyl groups, carbonyl groups, carboxylic acid groups, ester groups, cyano groups, isocyano groups, hydroxyl groups, mercapto groups, sulfinyl groups, sulfonyl groups, phosphino groups, and combinations thereof;

wherein,,

X _c And X _d And is selected identically or differently on each occurrence from the group consisting of: o, S, se and NR _N2 ；

R _a ，R _b ，R _c ，R _N1 ，R _N2 ，R _C1 And R is _C2 And 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 heterocyclyl having 3 to 20 ring 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 alkylsilyl having 3 to 20 carbon atoms, substituted or unsubstituted alkylsilyl having 6 to 20 carbon atoms, substituted or unsubstituted arylgermanium having 3 to 20 carbon atoms, substituted or unsubstituted arylgermanium having 6 to 20 carbon atoms, substituted or unsubstituted amino having 0 to 20 carbon atoms, acyl, carbonyl, carboxylic acid, ester, cyano, isocyano, hydroxy, mercapto, sulfinyl, sulfonyl, phosphino And combinations thereof;

17. The electroluminescent device of claim 15 wherein the phosphorescent material is a metal complex having M (L _a ) _m (L _b ) _n Is of the general formula (I);

m is selected from metals with a relative atomic mass greater than 40;

L _a has a structure as shown in formula 8:

wherein,,

ring D and ring E via U _a And U _b Condensing;

wherein the ligand L _b The structure is as follows:

wherein R is ₁ To R ₇ Each independently selected 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 heterocyclyl having 3 to 20 ring atoms, substituted or unsubstituted aralkyl having 7 to 30 carbon atoms, substituted or unsubstituted alkoxy having 1 to 20 carbon atoms, substitutedOr an unsubstituted aryloxy group having from 6 to 30 carbon atoms, a substituted or unsubstituted alkenyl group having from 2 to 20 carbon atoms, a substituted or unsubstituted aryl group having from 6 to 30 carbon atoms, a substituted or unsubstituted heteroaryl group having from 3 to 30 carbon atoms, a substituted or unsubstituted alkylsilyl group having from 3 to 20 carbon atoms, a substituted or unsubstituted arylsilyl group having from 6 to 20 carbon atoms, a substituted or unsubstituted alkylgermanium group having from 3 to 20 carbon atoms, a substituted or unsubstituted arylgermanium group having from 6 to 20 carbon atoms, a substituted or unsubstituted amino group having from 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;

Preferably, wherein R ₁ -R ₃ At least one or two of which are, identically or differently, selected from the group consisting of substituted or unsubstituted alkyl groups having from 1 to 20 carbon atoms, substituted or unsubstituted cycloalkyl groups having from 3 to 20 ring carbon atoms, substituted or unsubstituted heteroalkyl groups having from 1 to 20 carbon atoms, or combinations thereof; and/or R ₄ -R ₆ At least one or two of which are, identically or differently, selected from the group consisting of substituted or unsubstituted alkyl groups having from 1 to 20 carbon atoms, substituted or unsubstituted cycloalkyl groups having from 3 to 20 ring carbon atoms, substituted or unsubstituted heteroalkyl groups having from 1 to 20 carbon atoms, or combinations thereof;

more preferably, wherein R ₁ -R ₃ At least two of which are, identically or differently, selected from the group consisting of substituted or unsubstituted alkyl groups having from 2 to 20 carbon atoms, substituted or unsubstituted cycloalkyl groups having from 3 to 20 ring carbon atoms, substituted or unsubstituted heteroalkyl groups having from 2 to 20 carbon atoms, or combinations thereof; and/or R ₄ -R ₆ At least two of which are, identically or differently, selected from the group consisting of substituted or unsubstituted alkyl groups having from 2 to 20 carbon atoms, substituted or unsubstituted cycloalkyl groups having from 3 to 20 ring carbon atoms, substituted or unsubstituted heteroalkyl groups having from 2 to 20 carbon atoms, or combinations thereof.

18. A compound composition comprising a compound of any one of claims 1 to 11.

19. An electronic device comprising the electroluminescent device of any one of claims 12 to 17.