Organic electroluminescent materials and devices

Abstract

Organic electroluminescent materials and devices are disclosed. The organic electroluminescent material is a novel compound with benzodithiophene or a similar structure thereof, and can be used as a charge transport layer, a hole injection layer, a charge generation layer and the like in an electroluminescent device. These novel compounds can provide superior device performance compared to existing materials, such as further improving the voltage, efficiency and / or lifetime of OLEDs.

Description

[0001] This patent application is a divisional application of Chinese invention patent application No. 202210403486.8, with a priority date of December 13, 2017, an application date of December 02, 2018, and an invention name of “Organic electroluminescent materials and devices”. The Chinese invention patent application No. 202210403486.8 is a divisional application of Chinese invention patent application No. 201811460845.3, with a priority date of December 13, 2017, an application date of December 02, 2018, and an invention name of “Organic electroluminescent materials and devices”.

[0002] This application claims priority to U.S. Provisional Application No. 62 / 597,941, filed on December 13, 2017, the entire contents of which are incorporated herein by reference. Technical Field

[0003] 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 a benzodithiophene structure, a benzodifuran structure, a benzodiselenophene structure, or a similar structure thereof, and an organic electroluminescent device comprising the compound. Background Art

[0004] Organic electronic devices include but are not limited to the following categories: organic light emitting diodes (OLEDs), organic field effect transistors (O-FETs), organic light emitting transistors (OLETs), 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 plasmonic light emitting devices.

[0005] In 1987, Tang and Van Slyke of Eastman Kodak reported a double-layer organic electroluminescent device, which included an arylamine hole transport layer and a tri-8-hydroxyquinoline-aluminum layer as an electron transport layer and a light-emitting layer (Applied Physics Letters, 1987, 51 (12): 913-915). Once a bias voltage is applied to the device, green light is emitted from the device. This invention laid the foundation for the development of modern organic light-emitting diodes (OLEDs). The most advanced OLEDs can 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 the anode. Since OLEDs are self-luminous solid-state devices, they offer great potential for display and lighting applications. In addition, the inherent properties of organic materials, such as their flexibility, can make them very suitable for special applications, such as on flexible substrates.

[0006] OLEDs can be divided into three different types based on their light emission mechanism. The OLED invented by Tang and van Slyke is a fluorescent OLED. It uses only singlet light emission. The triplet generated in the device is wasted through non-radiative decay channels. Therefore, the internal quantum efficiency (IQE) of fluorescent OLEDs is only 25%. This limitation has hindered the commercialization of OLEDs. In 1997, Forrest and Thompson reported phosphorescent OLEDs, which used triplet light emission from heavy metals containing complexes as emitters. Therefore, singlet and triplet states can be harvested, achieving 100% IQE. Due to its high efficiency, the discovery and development of phosphorescent OLEDs directly contributed to the commercialization of active matrix OLEDs (AMOLEDs). Recently, Adachi achieved high efficiency through thermally activated delayed fluorescence (TADF) of organic compounds. These emitters have a small singlet-triplet gap, making it possible for excitons to return from triplet to singlet. In TADF devices, triplet excitons can generate singlet excitons through reverse intersystem crossing, resulting in high IQE.

[0007] OLEDs can also be classified into small molecule and polymer OLEDs based on the form of the material used. Small molecules are any organic or organometallic material that is not a polymer. Small molecules can have a large molecular weight as long as they have a precise structure. Dendrimers with well-defined structures are considered small molecules. Polymer OLEDs include conjugated polymers and non-conjugated polymers with pendant luminescent groups. Small molecule OLEDs can become polymer OLEDs if post-polymerization occurs during the manufacturing process.

[0008] There are various OLED manufacturing methods. Small molecule OLEDs are usually manufactured by vacuum thermal evaporation. Polymer OLEDs are manufactured by solution methods such as spin coating, inkjet printing, and nozzle printing. Small molecule OLEDs can also be manufactured by solution methods if the material can be dissolved or dispersed in a solvent.

[0009] The emission color of OLED can be achieved by the structural design of the luminescent material. OLED can include one luminescent layer or multiple luminescent layers to achieve the desired spectrum. Green, yellow and red OLEDs, phosphorescent materials have been successfully commercialized. Blue phosphorescent devices still have problems such as blue unsaturation, short device life and high operating voltage. Commercial full-color OLED displays usually adopt a hybrid strategy, using blue fluorescence and phosphorescent yellow, or red and green. At present, the efficiency of phosphorescent OLEDs decreases rapidly under high brightness conditions, which is still a problem. In addition, it is expected to have a more saturated emission spectrum, higher efficiency and longer device life.

[0010] In OLED devices, the hole injection layer (HIL) facilitates hole injection from the ITO anode to the organic layer. In order to achieve low device driving voltage, it is important to have a minimum charge injection barrier from the anode. Various HIL materials have been developed, such as triarylamine compounds with shallow HOMO energy levels, very electron-deficient heterocyclic compounds, and triarylamine compounds doped with P-type conductivity dopants. In order to improve OLED performance, such as longer device life, higher efficiency and / or lower voltage, it is crucial to develop HIL and HTL materials with better performance. Summary of the invention

[0011] The present invention aims to solve at least part of the above problems by using a charge transport layer or a hole injection layer comprising benzodithiophene or a compound with a similar structure thereof. In addition, a charge generation layer comprising benzodithiophene or a compound with a similar structure thereof is provided, which can be used for a P-type charge generation layer in a tandem OLED structure, and can provide better device performance, such as further improving the voltage, efficiency and / or life of the OLED.

[0012] According to one embodiment of the present invention, a compound having a structure of Formula 1 is disclosed:

[0013]

[0014] in

[0015] X1, X2, X3, and X4 are each independently selected from CR or N; when X1, X2, X3, and X4 are each independently selected from CR, each R may be the same or different, and at least one of the Rs comprises at least one electron withdrawing group;

[0016] Z1 and Z2 are each independently selected from O, S, Se, S=O or SO2;

[0017] X and Y are each independently selected from S, Se, NR' or CR"R"';

[0018] R, R', R", and R'" are each independently selected from the group consisting of hydrogen, deuterium, halogen, substituted or unsubstituted alkyl having 1-20 carbon atoms, substituted or unsubstituted cycloalkyl having 3-20 ring carbon atoms, substituted or unsubstituted heteroalkyl having 1-20 carbon atoms, substituted or unsubstituted aralkyl having 7-30 carbon atoms, substituted or unsubstituted alkoxy having 1-20 carbon atoms, substituted or unsubstituted aryloxy having 6-30 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, substituted or unsubstituted alkylsilyl groups having 3 to 20 carbon atoms, substituted or unsubstituted arylsilyl groups having 6 to 20 carbon atoms, substituted or unsubstituted amine groups, acyl groups, carbonyl groups, carboxylic acid groups, ester groups, nitrile groups, isonitrile groups, sulfanyl groups, sulfinyl groups, sulfonyl groups, phosphino groups, and combinations thereof having 0 to 20 carbon atoms;

[0019] Any adjacent substitutions may be optionally linked to form a ring or fused structure.

[0020] According to another embodiment of the present invention, an electroluminescent device is also disclosed, comprising an anode, a cathode, and an organic layer disposed between the anode and the cathode, wherein the organic layer comprises a compound having Formula 1:

[0021]

[0022] in

[0023] X1, X2, X3, and X4 are each independently selected from CR or N; when X1, X2, X3, and X4 are each independently selected from CR, each R may be the same or different, and at least one of the Rs comprises at least one electron withdrawing group;

[0024] Z1 and Z2 are each independently selected from O, S, Se, S=O or SO2;

[0025] X and Y are each independently selected from S, Se, NR' or CR"R"';

[0026] R, R', R", and R'" are each independently selected from the group consisting of hydrogen, deuterium, halogen, substituted or unsubstituted alkyl having 1-20 carbon atoms, substituted or unsubstituted cycloalkyl having 3-20 ring carbon atoms, substituted or unsubstituted heteroalkyl having 1-20 carbon atoms, substituted or unsubstituted aralkyl having 7-30 carbon atoms, substituted or unsubstituted alkoxy having 1-20 carbon atoms, substituted or unsubstituted aryloxy having 6-30 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, substituted or unsubstituted alkylsilyl groups having 3 to 20 carbon atoms, substituted or unsubstituted arylsilyl groups having 6 to 20 carbon atoms, substituted or unsubstituted amine groups, acyl groups, carbonyl groups, carboxylic acid groups, ester groups, nitrile groups, isonitrile groups, sulfanyl groups, sulfinyl groups, sulfonyl groups, phosphino groups, and combinations thereof having 0 to 20 carbon atoms;

[0027] Any adjacent substitutions may be optionally linked to form a ring or fused structure.

[0028] According to another embodiment of the present invention, an organic electroluminescent device is also disclosed, which includes a plurality of stacked layers between an anode and a cathode, wherein the stacked layers include a first light-emitting layer and a second light-emitting layer, wherein the first stacked layer includes a first light-emitting layer, the second stacked layer includes a second light-emitting layer, and a charge generation layer is disposed between the first stacked layer and the second stacked layer, wherein the charge generation layer includes a p-type charge generation layer and an n-type charge generation layer, wherein the p-type charge generation layer includes a compound according to Formula 1:

[0029]

[0030] in

[0031] X1, X2, X3, and X4 are each independently selected from CR or N; when X1, X2, X3, and X4 are each independently selected from CR, each R may be the same or different, and at least one of the Rs comprises at least one electron withdrawing group;

[0032] Z1 and Z2 are each independently selected from O, S, Se, S=O or SO2;

[0033] X and Y are each independently selected from S, Se, NR' or CR"R"';

[0034] R, R', R", and R'" are each independently selected from the group consisting of hydrogen, deuterium, halogen, substituted or unsubstituted alkyl having 1-20 carbon atoms, substituted or unsubstituted cycloalkyl having 3-20 ring carbon atoms, substituted or unsubstituted heteroalkyl having 1-20 carbon atoms, substituted or unsubstituted aralkyl having 7-30 carbon atoms, substituted or unsubstituted alkoxy having 1-20 carbon atoms, substituted or unsubstituted aryloxy having 6-30 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, substituted or unsubstituted alkylsilyl groups having 3 to 20 carbon atoms, substituted or unsubstituted arylsilyl groups having 6 to 20 carbon atoms, substituted or unsubstituted amine groups, acyl groups, carbonyl groups, carboxylic acid groups, ester groups, nitrile groups, isonitrile groups, sulfanyl groups, sulfinyl groups, sulfonyl groups, phosphino groups, and combinations thereof having 0 to 20 carbon atoms;

[0035] Any adjacent substitutions may be optionally linked to form a ring or fused structure.

[0036] The novel compounds containing benzodithiophene or a similar structure disclosed in the present invention can be used as charge transport materials, hole injection materials, etc. in organic electroluminescent devices. Compared with existing materials, these novel compounds can provide excellent device performance. BRIEF DESCRIPTION OF THE DRAWINGS

[0037] Figure 1 is a schematic diagram of an organic light-emitting device that may contain the compounds disclosed herein.

[0038] Figure 2 is a schematic diagram of a tandem organic light-emitting device that may contain the compounds disclosed herein.

[0039] Figure 3 is a schematic diagram of another tandem organic light-emitting device that may contain the compounds disclosed herein.

[0040] Figure 4 is a diagram showing structural formula 1 of a compound as disclosed herein. DETAILED DESCRIPTION

[0041] OLEDs can be manufactured on a variety of substrates, such as glass, plastic, and metal. Figure 1An organic light-emitting device 100 is shown schematically and non-limitingly. The figure is not necessarily drawn to scale, and some layer structures in the figure may be omitted as needed. 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 can be manufactured by depositing the described layers in sequence. The properties and functions of each layer and exemplary materials are described in more detail in columns 6-10 of U.S. Patent No. 7,279,704 B2, the entire contents of which are incorporated herein by reference.

[0042] There are more examples 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 m-MTDATA doped with F4-TCNQ at a molar ratio of 50:1, as disclosed in U.S. Patent Application Publication No. 2003 / 0230980, which is incorporated by reference in its entirety. An example of a host material is disclosed in U.S. Patent No. 6,303,238 to Thompson et al., which is incorporated by reference in its entirety. An example of an n-doped electron transport layer is BPhen doped with Li at a molar ratio of 1:1, as disclosed in U.S. Patent Application Publication No. 2003 / 0230980, which is incorporated by reference in its entirety. U.S. Patent Nos. 5,703,436 and 5,707,745, which are incorporated by reference in their entirety, disclose examples of cathodes including composite cathodes having a thin layer of metal such as Mg:Ag with an overlying transparent, conductive, sputter-deposited ITO layer. The principles and use of barrier layers are described in more detail in U.S. Patent No. 6,097,147 and U.S. Patent Application Publication No. 2003 / 0230980, which are incorporated by reference in their entirety. Examples of injection 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.

[0043] The above-described layered structure is provided by way of non-limiting example. The functionality of an OLED can be achieved by combining the various layers described above, or some layers, such as an electron blocking layer, can be completely omitted. It can also include other layers that are not explicitly described. Within each layer, a single material or a mixture of multiple materials can be used to achieve optimal performance. Any functional layer can include several sublayers. For example, a light-emitting layer can have two layers of different light-emitting materials to achieve a desired light-emitting spectrum. For another example, a hole transport layer can have a first hole transport layer and a second hole transport layer.

[0044] 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.

[0045] In one embodiment, two or more OLED units may be connected in series to form a series OLED, such as Figure 2 A tandem organic light-emitting device 500 is schematically and non-limitingly shown. The device 500 may include a substrate 101, an anode 110, a first unit 100, a charge generation layer 300, a second unit 200, and a cathode 290. The first unit 100 includes 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, and an electron transport layer 170, the second unit 200 includes a hole injection layer 220, a hole transport layer 230, an electron blocking layer 240, a light-emitting layer 250, a hole blocking layer 260, an electron transport layer 270, and an electron injection layer 280, and the charge generation layer 300 includes an N-type charge generation layer 310 and a P-type charge generation layer 320. The device 500 can be manufactured by depositing the described layers in sequence.

[0046] OLED can also be provided with an encapsulation layer, such as Figure 3 The organic light emitting device 600 is schematically and non-limitingly shown. Figure 2 The difference is that an encapsulation layer 102 may also be included on the cathode 290 to prevent harmful substances from the environment, such as moisture and oxygen. Any material that can provide an encapsulation function can be used as an encapsulation layer, such as glass or an organic-inorganic hybrid layer. The encapsulation layer should be placed directly or indirectly on the outside of the OLED device. Multilayer thin film encapsulation is described in U.S. Patent No. 7,968,146 B2, the entire contents of which are incorporated herein by reference.

[0047] Devices manufactured according to embodiments of the present invention can be incorporated into various consumer products having one or more electronic component modules (or units) of the device. Some examples of these consumer products include flat panel displays, monitors, medical monitors, televisions, billboards, lights for indoor or outdoor lighting and / or signaling, heads-up displays, fully or partially transparent displays, 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.

[0048] The materials and structures described herein may also be used in other organic electronic devices listed above.

[0049] As used herein, "top" means farthest from the substrate, while "bottom" means closest to the substrate. Where a first layer is described as being "disposed" "on" a second layer, the first layer is disposed farther from the substrate. Unless it is specified that the first layer is "in contact with" the second layer, other layers may be present between the first and second layers. For example, a cathode may be described as being "disposed" "on" an anode even though various organic layers are present between the cathode and the anode.

[0050] 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.

[0051] A ligand may be referred to as "photoactive" when it is believed that the ligand directly contributes to the photoactive property of the emissive material. A ligand may be referred to as "ancillary" when it is believed that the ligand does not contribute to the photoactive property of the emissive material, but the ancillary ligand may alter the properties of the photoactive ligand.

[0052] It is believed that the internal quantum efficiency (IQE) of fluorescent OLEDs can exceed the 25% spin-statistical limit through delayed fluorescence. Delayed fluorescence can generally be divided into two types, namely P-type delayed fluorescence and E-type delayed fluorescence. P-type delayed fluorescence is generated by triplet-triplet annihilation (TTA).

[0053] On the other hand, E-type delayed fluorescence does not rely on the collision of two triplets, but on the conversion between triplet and singlet excited state. Compounds capable of producing E-type delayed fluorescence need to have a very small single-triplet gap for the conversion between energy states. Thermal energy can activate the transition from triplet back to singlet. This type of delayed fluorescence is also called thermally activated delayed fluorescence (TADF). The notable feature of TADF is that the delayed component increases with increasing temperature. If the reverse intersystem crossing (IRISC) rate is fast enough to minimize the non-radiative decay by triplet, the fraction of backfilling singlet excited state may reach 75%. The total singlet fraction can be 100%, far exceeding the 25% of the spin statistics of the excitons generated by electricity.

[0054] The E-type delayed fluorescence feature can be seen in an exciplex system or a single compound. Without being bound by theory, it is believed that the E-type delayed fluorescence requires the luminescent material to have a small singlet-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 usually characterized by donor-acceptor charge transfer (CT) type emission. The spatial separation of the HOMO and LUMO in these donor-acceptor type compounds usually produces a small ΔE S-TThese states may include CT states. Generally, donor-acceptor light-emitting materials are constructed by linking an electron donor moiety (eg, an amino group or a carbazole derivative) to an electron acceptor moiety (eg, a six-membered aromatic ring containing N).

[0055] Definition of Substituent Terms

[0056] Halogen or halide - as used herein includes fluorine, chlorine, bromine and iodine.

[0057] Alkyl - includes straight chain and branched chain alkyl groups. Examples of alkyl groups include methyl, ethyl, propyl, isopropyl, n-butyl, sec-butyl, isobutyl, tert-butyl, n-pentyl, n-hexyl, n-heptyl, n-octyl, n-nonyl, n-decyl, n-undecyl, n-dodecyl, n-tridecyl, n-tetradecyl, n-pentadecyl, n-hexadecyl, n-heptadecyl, n-octadecyl, neopentyl, 1-methylpentyl, 2-methylpentyl, 1-pentylhexyl, 1-butylpentyl, 1-heptyloctyl, 3-methylpentyl. In addition, the alkyl group may be optionally substituted. The carbon in the alkyl chain may be substituted with other heteroatoms. Among the above, methyl, ethyl, propyl, isopropyl, n-butyl, sec-butyl, isobutyl, tert-butyl, n-pentyl and neopentyl are preferred.

[0058] Cycloalkyl - as used herein includes cyclic alkyl groups. Preferred cycloalkyl groups are those containing 4 to 10 ring carbon atoms, including cyclobutyl, cyclopentyl, cyclohexyl, 4-methylcyclohexyl, 4,4-dimethylcyclohexyl, 1-adamantyl, 2-adamantyl, 1-norbornyl, 2-norbornyl, and the like. In addition, cycloalkyl groups may be optionally substituted. The carbons in the ring may be substituted with other heteroatoms.

[0059] Alkenyl - As used herein, linear and branched olefin groups are encompassed. Preferred alkenyl groups are alkenyl groups containing 2 to 15 carbon atoms. Examples of alkenyl groups include vinyl, allyl, 1-butenyl, 2-butenyl, 3-butenyl, 1,3-butadienyl, 1-methylvinyl, styryl, 2,2-diphenylvinyl, 1,2-diphenylvinyl, 1-methylallyl, 1,1-dimethylallyl, 2-methylallyl, 1-phenylallyl, 2-phenylallyl, 3-phenylallyl, 3,3-diphenylallyl, 1,2-dimethylallyl, 1-phenyl-1-butenyl and 3-phenyl-1-butenyl. In addition, alkenyl groups may be optionally substituted.

[0060] Alkynyl - as used herein, encompasses both straight and branched chain alkynyl groups. Preferred alkynyl groups are those containing 2 to 15 carbon atoms. Additionally, alkynyl groups may be optionally substituted.

[0061] Aryl or aromatic group - As used herein, non-fused and fused systems are contemplated. Preferred aryl groups are those containing 6 to 60 carbon atoms, more preferably 6 to 20 carbon atoms, more preferably 6 to 12 carbon atoms. Examples of aryl groups include phenyl, biphenyl, terphenyl, triphenylene, tetraphenylene, naphthalene, anthracene, phenanthrene, phenanthrene, fluorene, pyrene, letrozole, perylene and azulene, preferably phenyl, biphenyl, terphenyl, triphenylene, fluorene and naphthalene. In addition, aryl groups may be optionally substituted. Examples of non-fused aryl groups include phenyl, biphenyl-2-yl, biphenyl-3-yl, biphenyl-4-yl, p-terphenyl-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-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-quaterphenyl.

[0062] Heterocyclyl or heterocycle - As used herein, both aromatic and non-aromatic cyclic groups are contemplated. Heteroaryl also refers to heteroaryl. Preferred non-aromatic heterocyclyls are those containing 3 to 7 ring atoms, including at least one heteroatom such as nitrogen, oxygen and sulfur. The heterocyclyl may also be an aromatic heterocyclyl having at least one heteroatom selected from nitrogen, oxygen, sulfur and selenium atoms.

[0063] Heteroaryl - As used herein, non-fused and fused heteroaromatic groups that may contain from 1 to 5 heteroatoms are contemplated. Preferred heteroaryl groups are those containing from 3 to 30 carbon atoms, more preferably from 3 to 20 carbon atoms, more preferably from 3 to 12 carbon atoms. Suitable heteroaryl groups include dibenzothiophene, dibenzofuran, dibenzoselenophene, furan, thiophene, benzofuran, benzothiophene, benzoselenophene, carbazole, indolecarbazole, pyridineindole, pyrrolopyridine, pyrazole, imidazole, triazole, oxazole, thiazole, oxadiazole, oxatriazole, dioxazole, thiadiazole, pyridine, pyridazine, pyrimidine, pyrazine, triazine, oxazine, oxathiazine, oxadiazine, indole, benzimidazole, indazole, indazine, benzoxazole, benzisoxazole, benzothiazole, quinoline, isoquinoline, In some embodiments, the heteroaryl group comprises an oxadiazole, an isocyanine ...

[0064] Alkoxy - is represented by -O-alkyl. Examples and preferred examples of alkyl are the same as those described above. Examples of alkoxy having 1 to 20 carbon atoms, preferably 1 to 6 carbon atoms, include methoxy, ethoxy, propoxy, butoxy, pentyloxy and hexyloxy. Alkoxy having 3 or more carbon atoms may be linear, cyclic or branched.

[0065] Aryloxy- is represented by -O-aryl or -O-heteroaryl. Examples and preferred examples of aryl and heteroaryl are the same as described above. Examples of aryloxy having 6 to 40 carbon atoms include phenoxy and biphenyloxy.

[0066] Aralkyl - As used herein, an alkyl group having an aryl substituent. In addition, the aralkyl group may be optionally substituted. 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-hydroxybenzyl, p-aminobenzyl, m-aminobenzyl, o-aminobenzyl, p-nitrobenzyl, m-nitrobenzyl, o-nitrobenzyl, p-cyanobenzyl, m-cyanobenzyl, o-cyanobenzyl, 1-2-hydroxy-2-phenylisopropyl and 1-chloro-2-phenylisopropyl. Among the above, benzyl, p-cyanobenzyl, m-cyanobenzyl, o-cyanobenzyl, 1-phenylethyl, 2-phenylethyl, 1-phenylisopropyl and 2-phenylisopropyl are preferred.

[0067] The term "aza" in azadibenzofuran, aza-dibenzothiophene, etc. means that one or more CH groups in the corresponding aromatic fragment are replaced by a nitrogen atom. For example, azatriphenylene includes dibenzo[f,h]quinoxaline, dibenzo[f,h]quinoline and other analogs having two or more nitrogens in the ring system. Other nitrogen analogs of the above-mentioned aza derivatives can be easily thought of by those of ordinary skill in the art, and all such analogs are determined to be included in the terms described herein.

[0068] The alkyl, cycloalkyl, alkenyl, alkynyl, aralkyl, heterocyclyl, aryl and heteroaryl groups may be unsubstituted or may be substituted with one or more groups selected from deuterium, halogen, alkyl, cycloalkyl, aralkyl, alkoxy, aryloxy, amino, cyclic amino, silyl, alkenyl, cycloalkenyl, heteroalkenyl, alkynyl, aryl, heteroaryl, acyl, carbonyl, carboxylic acid, ether, ester, nitrile, isonitrile, sulfanyl, sulfinyl, sulfonyl, phosphino and combinations thereof.

[0069] It should be understood that when describing a molecular fragment as a substituent or otherwise attached to another moiety, its name can be written according to whether it is a fragment (e.g., phenyl, phenylene, naphthyl, dibenzofuranyl) or according to whether it is a whole molecule (e.g., benzene, naphthalene, dibenzofuran). As used herein, these different ways of specifying a substituent or attaching a fragment are considered equivalent.

[0070] In the compounds mentioned in this disclosure, 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. The replacement of other stable isotopes in the compounds may be preferred because it enhances the efficiency and stability of the device.

[0071] In the compounds referred to in this disclosure, multiple substitutions are meant to include double substitutions up to the maximum number of available substitutions.

[0072] In the compounds mentioned in this disclosure, the statement that adjacent substituents can optionally be linked to form a ring is intended to be taken to mean that the two groups are linked to each other by a chemical bond. This is exemplified by the following formula:

[0073]

[0074] Furthermore, the statement 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 two groups represents hydrogen, the second group is bonded at the position to which the hydrogen atom is bonded, thereby forming a ring. This is exemplified by the following formula:

[0075]

[0076] According to one embodiment of the present invention, a compound having Formula 1 is disclosed:

[0077]

[0078] in

[0079] X1, X2, X3, and X4 are each independently selected from the group consisting of CR and N; when X1, X2, X3, and X4 are each independently selected from CR, each R may be the same or different, and at least one of the Rs comprises at least one electron withdrawing group;

[0080] Z1 and Z2 are each independently selected from the group consisting of O, S, Se, S=O and SO2;

[0081] X and Y are each independently selected from the group consisting of S, Se, NR' and CR"R"';

[0082] R, R', R", and R'" are each independently selected from the group consisting of hydrogen, deuterium, halogen, substituted or unsubstituted alkyl having 1-20 carbon atoms, substituted or unsubstituted cycloalkyl having 3-20 ring carbon atoms, substituted or unsubstituted heteroalkyl having 1-20 carbon atoms, substituted or unsubstituted aralkyl having 7-30 carbon atoms, substituted or unsubstituted alkoxy having 1-20 carbon atoms, substituted or unsubstituted aryloxy having 6-30 carbon atoms, substituted or unsubstituted alkyl having 2-20 carbon atoms, substituted or unsubstituted aryl groups having 6 to 30 carbon atoms, substituted or unsubstituted heteroaryl groups having 3 to 30 carbon atoms, substituted or unsubstituted alkylsilyl groups having 3 to 20 carbon atoms, substituted or unsubstituted arylsilyl groups having 6 to 20 carbon atoms, substituted or unsubstituted amino groups, acyl groups, carbonyl groups, carboxylic acid groups, ester groups, nitrile groups, isonitrile groups, sulfanyl groups, sulfinyl groups, sulfonyl groups, phosphino groups, and combinations thereof;

[0083] Any adjacent substitutions may be optionally linked to form a ring or fused structure.

[0084] According to one embodiment of the present invention, Z1 and Z2 are S.

[0085] According to one embodiment of the present invention, X2 and X3 are N.

[0086] According to one embodiment of the present invention, X2 and X3 are each independently selected from CR, each R may be the same or different, and at least one of the R comprises at least one electron withdrawing group.

[0087] According to one embodiment of the present invention, X2 and X3 are each independently selected from CR, each R may be the same or different, and each of the R comprises at least one electron withdrawing group.

[0088] According to one embodiment of the present invention, R is selected from the group consisting of fluorine, chlorine, trifluoromethyl, trifluoromethoxy, pentafluoroethyl, pentafluoroethoxy, cyano, nitro, methanesulfonyl, trifluoromethanesulfonyl, trifluoromethylthio, pentafluorothio, pyridyl, 3-fluorophenyl, 4-fluorophenyl, 3-cyanophenyl, 4-cyanophenyl, 4-trifluoromethylphenyl, 3-trifluoromethoxyphenyl, 4-trifluoromethoxyphenyl, 4-pentafluoroethylphenyl, 4-pentafluoroethoxyphenyl, 4-nitrophenyl, 4-methanesulfonylphenyl, 4-trifluoromethanesulfonylphenyl, 3-trifluoromethylthiophenyl, 4-trifluoromethylthiophenyl, 4-pentafluorothiophenyl, pyrimidinyl, 2,6-dimethyl-1,3,5-triazine, and combinations thereof.

[0089] According to one embodiment of the present invention, X and Y are each independently CR"R"'.

[0090] According to one embodiment of the present invention, R', R", and R'" are each independently selected from the group consisting of trifluoromethyl, cyano, pentafluorophenyl, 4-cyano-2,3,5,6-tetrafluorophenyl and pyridyl.

[0091] According to a preferred embodiment of the present invention, the compound has a structure of any of the following formulas:

[0092]

[0093] In the above formulas, each R may be the same or different, and at least one of the R in each formula comprises at least one electron withdrawing group;

[0094] Z1 and Z2 are each independently selected from O, S, Se, S=O or SO2;

[0095] R, R', R", and R'" are each independently selected from the group consisting of hydrogen, deuterium, halogen, substituted or unsubstituted alkyl having 1-20 carbon atoms, substituted or unsubstituted cycloalkyl having 3-20 ring carbon atoms, substituted or unsubstituted heteroalkyl having 1-20 carbon atoms, substituted or unsubstituted aralkyl having 7-30 carbon atoms, substituted or unsubstituted alkoxy having 1-20 carbon atoms, substituted or unsubstituted aryloxy having 6-30 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, substituted or unsubstituted alkylsilyl groups having 3 to 20 carbon atoms, substituted or unsubstituted arylsilyl groups having 6 to 20 carbon atoms, substituted or unsubstituted amine groups, acyl groups, carbonyl groups, carboxylic acid groups, ester groups, nitrile groups, isonitrile groups, sulfanyl groups, sulfinyl groups, sulfonyl groups, phosphino groups, and combinations thereof having 0 to 20 carbon atoms;

[0096] Any adjacent substitutions may be optionally linked to form a ring or fused structure.

[0097] According to a preferred embodiment of the present invention, the compound is selected from the group consisting of compounds O-1 to O-557, compounds S-1 to S-557, and compounds Se-1 to Se-557. The specific structures of compounds O-1 to O-557, compounds S-1 to S-557, and compounds Se-1 to Se-557 are as follows:

[0098]

[0099]

[0100]

[0101]

[0102]

[0103]

[0104]

[0105]

[0106]

[0107]

[0108]

[0109]

[0110]

[0111]

[0112]

[0113]

[0114]

[0115]

[0116]

[0117]

[0118]

[0119]

[0120]

[0121]

[0122]

[0123]

[0124]

[0125]

[0126]

[0127]

[0128]

[0129]

[0130]

[0131]

[0132]

[0133]

[0134]

[0135]

[0136]

[0137] According to one embodiment of the present invention, an electroluminescent device is also disclosed, comprising:

[0138] anode,

[0139] cathode,

[0140] and an organic layer disposed between the anode and the cathode, wherein the organic layer comprises a compound having Formula 1:

[0141]

[0142] in

[0143] X1, X2, X3, and X4 are each independently selected from the group consisting of CR and N; when X1, X2, X3, and X4 are each independently selected from CR, each R may be the same or different, and at least one of the Rs comprises at least one electron withdrawing group;

[0144] Z1 and Z2 are each independently selected from the group consisting of O, S, Se, S=O and SO2;

[0145] X and Y are each independently selected from the group consisting of S, Se, NR' and CR"R"';

[0146] R, R', R", and R'" are each independently selected from the group consisting of hydrogen, deuterium, halogen, substituted or unsubstituted alkyl having 1-20 carbon atoms, substituted or unsubstituted cycloalkyl having 3-20 ring carbon atoms, substituted or unsubstituted heteroalkyl having 1-20 carbon atoms, substituted or unsubstituted aralkyl having 7-30 carbon atoms, substituted or unsubstituted alkoxy having 1-20 carbon atoms, substituted or unsubstituted aryloxy having 6-30 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, substituted or unsubstituted alkylsilyl groups having 3 to 20 carbon atoms, substituted or unsubstituted arylsilyl groups having 6 to 20 carbon atoms, substituted or unsubstituted amine groups, acyl groups, carbonyl groups, carboxylic acid groups, ester groups, nitrile groups, isonitrile groups, sulfanyl groups, sulfinyl groups, sulfonyl groups, phosphino groups, and combinations thereof having 0 to 20 carbon atoms;

[0147] Any adjacent substitutions may be optionally linked to form a ring or fused structure.

[0148] According to an embodiment of the present invention, the organic layer is a charge transport layer.

[0149] According to an embodiment of the present invention, the organic layer is a hole injection layer.

[0150] According to an embodiment of the present invention, the organic layer is a charge transport layer, and the organic layer further comprises an arylamine compound.

[0151] According to an embodiment of the present invention, the organic layer is a hole injection layer, and the organic layer further comprises an arylamine compound.

[0152] According to an embodiment of the present invention, the device further comprises a light-emitting layer.

[0153] According to another embodiment of the present invention, an organic electroluminescent device is also disclosed, which includes a plurality of stacks between an anode and a cathode, wherein the stack includes a first light-emitting layer and a second light-emitting layer, wherein the first stack includes a first light-emitting layer, the second stack includes a second light-emitting layer, and a charge generation layer is disposed between the first stack and the second stack, wherein the charge generation layer includes a p-type charge generation layer and an n-type charge generation layer, wherein the p-type charge generation layer includes a compound according to Formula 1:

[0154]

[0155] in

[0156] X1, X2, X3, and X4 are each independently selected from the group consisting of CR and N; when X1, X2, X3, and X4 are each independently selected from CR, each R may be the same or different, and at least one of the Rs comprises at least one electron withdrawing group;

[0157] Z1 and Z2 are each independently selected from the group consisting of O, S, Se, S=O and SO2;

[0158] X and Y are each independently selected from the group consisting of S, Se, NR' and CR"R"';

[0159] R, R', R", and R'" are each independently selected from the group consisting of hydrogen, deuterium, halogen, substituted or unsubstituted alkyl having 1-20 carbon atoms, substituted or unsubstituted cycloalkyl having 3-20 ring carbon atoms, substituted or unsubstituted heteroalkyl having 1-20 carbon atoms, substituted or unsubstituted aralkyl having 7-30 carbon atoms, substituted or unsubstituted alkoxy having 1-20 carbon atoms, substituted or unsubstituted aryloxy having 6-30 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, substituted or unsubstituted alkylsilyl groups having 3 to 20 carbon atoms, substituted or unsubstituted arylsilyl groups having 6 to 20 carbon atoms, substituted or unsubstituted amine groups, acyl groups, carbonyl groups, carboxylic acid groups, ester groups, nitrile groups, isonitrile groups, sulfanyl groups, sulfinyl groups, sulfonyl groups, phosphino groups, and combinations thereof having 0 to 20 carbon atoms;

[0160] Any adjacent substitutions may be optionally linked to form a ring or fused structure.

[0161] Combination with other materials

[0162] The materials for specific layers in the organic light-emitting device described in the present invention can be used in combination with various other materials present in the device. The combination of these materials is described in detail in paragraphs 0132-0161 of U.S. Patent Application US2016 / 0359122A1, the entire contents of which are incorporated herein by reference. The materials described or mentioned therein are non-limiting examples of materials that can be used in combination with the compounds disclosed herein, and those skilled in the art can easily consult the literature to identify other materials that can be used in combination.

[0163] The materials described herein as specific layers that can be used in organic light-emitting devices can be used in combination with a variety of other materials present in the device. For example, the materials disclosed herein can be used in combination with a variety of luminescent, main body, transport layer, barrier layer, injection layer, electrode and other possible layers. The combination of these materials is described in detail in paragraphs 0080-0101 of patent application US2015 / 0349273A1, the entire contents of which are incorporated herein by reference. The materials described or mentioned therein are non-limiting examples of materials that can be used in combination with the compounds disclosed herein, and those skilled in the art can easily consult the literature to identify other materials that can be used in combination.

[0164] In the embodiment of material synthesis, unless otherwise stated, all reactions are carried out under nitrogen protection. All reaction solvents are anhydrous and used as they are from commercial sources. The synthetic product uses one or more conventional equipment in the art (including but not limited to Bruker's nuclear magnetic resonance instrument, Shimadzu's liquid chromatograph, liquid chromatography-mass spectrometer, gas chromatography-mass spectrometer, differential scanning calorimeter, Shanghai Lingguang Technology's fluorescence spectrophotometer, Wuhan Cost's electrochemical workstation, Anhui Bei Yi Ke's sublimator, etc.), and the structure is confirmed and the characteristics are tested by methods well known to those skilled in the art. In the embodiment of the device, the characteristics of the device are also tested by methods well known to those skilled in the art using conventional equipment in the art (including but not limited to Angstrom Engineering's evaporation machine, Suzhou Fushida's optical test system, life test system, Beijing Liangtuo's ellipsometer, etc.). Since those skilled in the art are aware of the use of the above-mentioned equipment, test methods and other related contents, it is possible to obtain the inherent data of the sample with certainty and without being affected, so the above-mentioned related contents are no longer expanded in this patent.

[0165] Material synthesis example:

[0166] The preparation method of the compound of the present invention is not limited, and the following compounds are typically but not limitedly exemplified, and their synthetic routes and preparation methods are as follows:

[0167] Synthesis Example 1: Synthesis of Compound S-1

[0168] Step 1: Synthesis of intermediate S-1-1

[0169]

[0170] Methyl 2-mercaptoacetate (14 mL, 159 mmol) was added dropwise to a solution of 2,3,5,6-tetrafluoroterephthalaldehyde (15.6 g, 75.7 mmol) and triethylamine (42 mL, 303 mmol) in ethanol (300 mL) at room temperature, followed by stirring at 60° C. for 12 hours. The solution was cooled to room temperature and filtered, and the solid was washed with a small amount of ethanol to obtain intermediate S-1-1 (20 g, yield 77%) as a yellow solid.

[0171] Step 2: Synthesis of intermediate S-1-2

[0172]

[0173] Lithium hydroxide aqueous solution (234 mL, 1N) was added to a suspension of dimethyl 4,8-difluorobenzo[1,2-b:4,5-b']dithiophene-2,6-dicarboxylate (20 g, 58.5 mmol) in THF (200 mL), followed by stirring at 75 ° C for 12 hours. The solution was cooled to room temperature and hydrochloric acid (500 mL, 2N) was added, the solid was collected by filtration and washed with a small amount of water, and vacuum dried to give the intermediate S-1-2 (19 g, yield 99%) as a yellow solid.

[0174] Step 3: Synthesis of intermediate S-1-3

[0175]

[0176] Copper powder (750 mg, 11.7 mmol) was added to a suspension of 4,8-difluorobenzo[1,2-b:4,5-b']dithiophene-2,6-dicarboxylic acid (20 g, 58.5 mmol) in quinoline (100 mL), and then stirred at 260 ° C for 3 hours. The solution was cooled to room temperature and hydrochloric acid (500 mL, 3N) was added, the mixture was extracted with EA (200 mL*3), the organic phases were combined and washed with hydrochloric acid (300 mL, 3N) and brine in sequence and dried over magnesium sulfate. The resultant was separated by column chromatography and recrystallized from n-hexane and DCM to obtain intermediate S-1-3 (6 g, yield 45%) as a white solid.

[0177] Step 4: Synthesis of intermediate S-1-4

[0178]

[0179] Under stirring at -78°C, n-butyl lithium (16 mL, 2.5 M) was added dropwise to a solution of 4,8-difluorobenzo[1,2-b:4,5-b']dithiophene (3 g, 13.27 mmol) in THF (130 mL). After being kept at the same temperature for 1 hour, the reaction temperature was slowly raised to room temperature and kept at room temperature for 10 minutes. The reaction was then cooled to -78°C again with a cold bath and kept for 30 minutes. A solution of iodine (10 g, 39.8 mmol) in THF (20 mL) was added, the cold bath was removed and stirred overnight. The reaction was quenched with saturated ammonium chloride solution (100 mL), the aqueous layer was extracted with DCM (100 mL*3), the organic phases were combined and washed with sodium thiosulfate aqueous solution (100 mL, 1 N) and brine in sequence and dried over magnesium sulfate. The solvent was removed and recrystallized from DCM to give the intermediate S-1-4 (5.3 g, yield 90%) as a white solid.

[0180] Step 5: Synthesis of intermediate S-1-5

[0181]

[0182] Under stirring at 0°C, sodium hydride (2.33 g, 59 mmol) was carefully added to a solution of malononitrile (1.84 g, 29.5 mmol) in THF (100 mL). After 0.5 hours at the same temperature, 4,8-difluoro-2,6-diiodobenzo[1,2-b:4,5-b']dithiophene (5.3 g, 11.7 mmol) and tetrakistriphenylphosphine palladium (645 mg, 0.59 mmol) were added under nitrogen bubbling. After 20 minutes, the mixture was heated to 75°C for 12 hours. The solvent was removed and hydrochloric acid (100 mL, 2N) was added. The yellow precipitate was collected by filtration and washed with a small amount of water, ethanol and PE, and vacuum dried to give the intermediate S-1-5 (3.4 g, yield 86%) as a yellow solid.

[0183] Step 6: Synthesis of compound S-1

[0184]

[0185] [Bis(trifluoroacetoxy)iodo]benzene (PIFA, 4.3 g, 9.9 mmol) was added to a suspension of 2,2'-(4,8-difluorobenzo[1,2-b:4,5-b']dithiophene-2,6-diyl)bismalononitrile (3.4 g, 9 mmol) in DCM (100 mL), and then stirred at room temperature for 12 hours. The solvent was reduced to about 50 mL by vacuum evaporation and cooled to 0°C. The dark precipitate was collected by filtration and washed with DCM to obtain compound S-1 (2.1 g, yield 65%) as a black solid. It was further purified by vacuum sublimation. The obtained product was confirmed to be the target product with a molecular weight of 352.

[0186] Synthesis Example 2: Synthesis of Compound S-44

[0187] Step 1: Synthesis of intermediate S-44-1

[0188]

[0189] In a 500mL three-necked round-bottom flask, benzo[1,2-b:4,5-b']dithiophene-4,8-diylbis(trifluoromethanesulfonate) (13g, 27mmol) and (4-trifluoromethoxy)phenylboronic acid (13.9g, 67.5mmol) were dissolved in THF (200mL). Tetrakis(triphenylphosphine)palladium(0) (1.55g, 1.35mmol) and sodium carbonate solution (135mL, 1M) were added to the reaction mixture. The reaction mixture was heated at 75°C for 12 hours. Water was added to the reaction mixture, then extracted with DCM and washed with brine. The combined organic layer was concentrated. The crude product was purified by column chromatography to give the intermediate S-44-1 (11g, yield 80%) as a white solid.

[0190] Step 2: Synthesis of intermediate S-44-2

[0191]

[0192] The process of synthesizing S-1-4 was repeated, except that intermediate S-44-1 was used to replace intermediate S-1-3, to give intermediate S-44-2 (7.3 g, yield 80%) as a white solid.

[0193] Step 3: Synthesis of intermediate S-44-3

[0194]

[0195] The process of synthesizing S-1-5 was repeated, except that intermediate S-44-2 was used to replace intermediate S-1-4, to give intermediate S-44-3 (3.6 g, yield 60%) as a yellow solid.

[0196] Step 4: Synthesis of compound S-44

[0197]

[0198] The process of synthesizing S-1 was repeated, except that intermediate S-44-3 was used to replace intermediate S-1-5, to obtain compound S-44 (1.7 g, yield 45%) as a purple solid. The obtained product was confirmed to be the target product, with a molecular weight of 637.

[0199] Synthesis Example 3: Synthesis of Compound S-26

[0200] Step 1: Synthesis of intermediate S-26-1

[0201]

[0202] The process of synthesizing S-44-1 was repeated except that (3,4,5-trifluorophenyl)boronic acid was used instead of (4-trifluoromethoxy)phenylboronic acid to obtain the intermediate S-26-1 (10 g, yield 60%) as a white solid.

[0203] Step 2: Synthesis of intermediate S-26-2

[0204]

[0205] The process of synthesizing S-1-4 was repeated, except that intermediate S-26-1 was used to replace intermediate S-1-3, to obtain intermediate S-26-2 (6.8 g, yield 80%) as a white solid.

[0206] Step 3: Synthesis of intermediate S-26-3

[0207]

[0208] The process of synthesizing S-1-5 was repeated except that intermediate S-26-2 was used to replace intermediate S-1-4 to give intermediate S-26-3 (3.2 g, yield 60%) as a yellow solid.

[0209] Step 4: Synthesis of compound S-26

[0210]

[0211] The process of synthesizing S-1 was repeated, except that intermediate S-26-3 was used to replace intermediate S-1-5, to obtain compound S-26 (1.3 g, yield 47%) as a purple solid. The obtained product was confirmed to be the target product, with a molecular weight of 576.

[0212] Those skilled in the art should be aware that the above preparation method is only an illustrative example, and those skilled in the art can obtain other compound structures of the present invention by improving it.

[0213] Comparative Synthesis Example 1: Synthesis of Comparative Compound A-1

[0214] Step 1: Synthesis of intermediate A-1-1

[0215]

[0216] The process of synthesizing S-1-4 was repeated, except that intermediate S-1-3 and iodine were replaced by benzo[1,2-b:4,5-b']dithiophene and carbon tetrabromide, respectively, to obtain intermediate A-1-1 (3.2 g, yield 80%) as a light yellow solid.

[0217] Step 2: Synthesis of intermediate A-1-2

[0218]

[0219] The process of synthesizing S-1-5 was repeated, except that intermediate A-1-1 was used to replace intermediate S-1-4, to give intermediate A-1-2 (2.8 g, yield 97%) as a yellow solid.

[0220] Step 3: Synthesis of comparative compound A-1

[0221]

[0222] The process of synthesizing S-1 was repeated, except that the intermediate S-1-5 was replaced by the intermediate A-1-2, to obtain a black solid comparative compound A-1 (2.1 g, yield 75%). The obtained product was confirmed to be the target product, with a molecular weight of 316.

[0223] The above-mentioned synthesized compounds of the present invention can remain unchanged during the sublimation process, proving that they are suitable for the vacuum evaporation OLED preparation method. In contrast, the comparative compound A-1 deteriorates during the sublimation process, proving that it is not suitable for the vacuum evaporation OLED preparation method, and the comparative compound A-1 has a very low solubility in organic solutions, so it is also not suitable for the printing OLED preparation method.

[0224] The above-synthesized compound of the present invention is more electron-deficient than the comparative compound A-1. The LUMO of the compound S-1 and the compound S-44 is -4.74eV and -4.67eV respectively, while the comparative compound A-1 is only -4.30eV, which is more than 0.3eV different. This indicates that the compound S-1 and the compound S-44 are easier to reduce than the comparative compound A-1, and also indicates that the p-type conductivity doped triarylamine compound in the HIL and / or HTL can be more effectively achieved, which can improve the performance of OLED, such as longer device life, higher efficiency and / or lower voltage. This also proves that the compound of formula 1, one of the characteristics of which is that it carries electron-withdrawing groups at the positions of the five-membered ring X1 and X4 and / or the six-membered ring X2 and X3, can effectively enhance the electron-deficient nature of the molecule, reduce the LUMO, match the HOMO of the triarylamine compound, and form the p-type conductivity of the HIL and / or HTL. For example, if the five-membered ring and / or the six-membered ring in Formula 1 is a nitrogen heterocycle, a similar effect can be achieved because nitrogen in the heterocycle has an electron-withdrawing effect.

[0225] Device Embodiment

[0226] Device Example 1

[0227] A glass substrate with a 120 nm thick indium tin oxide (ITO) transparent electrode was treated with oxygen plasma and UV ozone. The cleaned glass substrate was dried on a hot plate in a glove box before evaporation. The following materials were heated to a vacuum of about 10 -8 In the case of support, the glass surface is sequentially evaporated at a rate of 0.2-2 angstroms / second. First, compound HI is evaporated on the surface of the glass to form a 10nm thick film as a hole injection layer (HIL). Next, compound HT and compound S-1 (weight ratio of 97:3) are co-evaporated on the above-mentioned obtained film to form a 20nm thick film as the first hole transport layer (HTL1). Then, compound HT is evaporated on the above-mentioned obtained film to form a 20nm thick film as the second hole transport layer (HTL2). Then, compound H1, compound H2 and compound GD (weight ratio of 45:45:10) are co-evaporated on the above-mentioned obtained film to form a 40nm thick film as a light-emitting layer (EML). Then, compound H2 is evaporated on the above-mentioned obtained film to form a 10nm thick film as a hole blocking layer (HBL). Then, 8-hydroxyquinoline-lithium (Liq) and compound ET (weight ratio of 60:40) were co-evaporated onto the above-obtained film to form a 35nm thick film as an electron transport layer (ETL). Finally, Liq was evaporated to form a 1nm thick film as an electron injection layer (EIL) and 120nm thick aluminum was evaporated as a cathode.

[0228] Device Example 2 was fabricated in the same manner as Device Example 1, except that Compound HT and Compound S-1 were used as HIL in a weight ratio of 91:9 (10 nm), and Compound HT and Compound S-1 were used as HTL1 in a weight ratio of 91:9 (20 nm).

[0229] Device Example 3 was prepared in the same manner as Device Example 1, except that in HTL1, Compound HT and Compound S-44 were used in a weight ratio of 97:3.

[0230] Device Example 4 was fabricated in the same manner as Device Example 2, except that Compound HT and Compound S-44 were used as HIL in a weight ratio of 97:3 (10 nm), and Compound HT and Compound S-44 were used as HTL1 in a weight ratio of 97:3 (20 nm).

[0231] Comparative Example 1 was prepared in the same manner as Device Example 1, except that Compound HT (20 nm) was used in HTL1.

[0232] Part of the device structure is shown in Table 1:

[0233] Table 1 Device Partial Structure of Device Example

[0234]

[0235] The material structure used in the device is shown below:

[0236]

[0237]

[0238] The device was measured at 1000cd / m 2 External quantum efficiency (EQE), current efficiency (CE) and CIE data under initial brightness of 21750cd / m 2 The relevant results are shown in Table 2.

[0239] Table 2 Device data

[0240]

[0241] discuss:

[0242] As shown in Table 2, device Example 1 using compound S-1 as a dopant in HTL1 has a better lifespan than Comparative Example 1 using only a representative HTL material in the art (196 h vs. 174 h). Device Example 2 using compound S-1 as a dopant in both HIL and HTL1 has a better lifespan than Comparative Example 1 using representative HIL and HTL materials in the art (202 h vs. 174 h). Device Example 3 using compound S-44 as a dopant in HTL1 has a much better lifespan than Comparative Example 1 using only a representative HTL material in the art (264 h vs. 174 h). Significantly, device Example 4 using compound S-44 as a dopant in both HIL and HTL1 layers has a much higher efficiency (27.18% vs. 22.06%, 90.35 cd / A vs. 75.25 cd / A) than Comparative Example 1 using representative HIL and HTL materials in the art, while maintaining a similar lifespan to Comparative Example 1 (171 h vs. 174 h). These results clearly show that the compound of Formula 1 of the present invention, when used in a hole injection layer or a hole transport layer, can provide performance comparable to or even better than existing representative materials, especially can improve the performance in terms of device lifespan or efficiency.

[0243] It should be understood that the various embodiments described herein are only examples and are not intended to limit the scope of the present invention. Therefore, as will be apparent to those skilled in the art, the claimed invention may include variations of the specific embodiments and preferred embodiments described herein. Many of the materials and structures described herein may be replaced with other materials and structures without departing from the spirit of the present invention. It should be understood that the various theories about why the present invention works are not intended to be restrictive.

Claims

1. An electroluminescent device, comprising: anode, cathode, An organic layer disposed between the anode and the cathode, wherein the organic layer comprises a compound having Formula 1: in X1, X2, X3, and X4 are each independently selected from CR or N; when X1, X2, X3, and X4 are each independently selected from CR, each R may be the same or different, and at least one of the Rs comprises at least one electron withdrawing group; Z1 and Z2 are each independently selected from O, S, Se, S=O or SO2; X and Y are each independently selected from CR"R"'; R, R", and R'" are each independently selected from the group consisting of hydrogen, deuterium, halogen, nitro, substituted or unsubstituted alkyl having 1-20 carbon atoms, substituted or unsubstituted cycloalkyl having 3-20 ring carbon atoms, substituted or unsubstituted heteroalkyl having 1-20 carbon atoms, substituted or unsubstituted aralkyl having 7-30 carbon atoms, substituted or unsubstituted alkoxy having 1-20 carbon atoms, substituted or unsubstituted aryloxy having 6-30 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, substituted or unsubstituted alkylsilyl groups having 3 to 20 carbon atoms, substituted or unsubstituted arylsilyl groups having 6 to 20 carbon atoms, substituted or unsubstituted amine groups, acyl groups, carbonyl groups, carboxylic acid groups, ester groups, nitrile groups, isonitrile groups, sulfanyl groups, sulfinyl groups, sulfonyl groups, phosphino groups, and combinations thereof having 0 to 20 carbon atoms; Any adjacent substitutions may be optionally linked to form a ring or fused structure.

2. The device according to claim 1, wherein the organic layer is a charge transport layer; preferably, wherein the organic layer further comprises an arylamine compound. 3 . The device according to claim 1 , wherein the organic layer is a hole injection layer; preferably, wherein the organic layer further comprises an arylamine compound. The device according to claim 1 , wherein the device further comprises a light emitting layer.

5. An organic electroluminescent device comprising a plurality of stacked layers between an anode and a cathode, the stacked layers comprising a first light-emitting layer and a second light-emitting layer, in, The first stacked layer includes a first light-emitting layer, the second stacked layer includes a second light-emitting layer, and the charge generation layer is disposed between the first stacked layer and the second stacked layer. The charge generation layer includes a p-type charge generation layer and an n-type charge generation layer. Wherein the p-type charge generation layer comprises a compound according to Formula 1: in X1, X2, X3, and X4 are each independently selected from CR or N; when X1, X2, X3, and X4 are each independently selected from CR, each R may be the same or different, and at least one of the Rs comprises at least one electron withdrawing group; Z1 and Z2 are each independently selected from O, S, Se, S=O or SO2; X and Y are each independently selected from CR"R"'; R, R", and R'" are each independently selected from the group consisting of hydrogen, deuterium, halogen, nitro, substituted or unsubstituted alkyl having 1-20 carbon atoms, substituted or unsubstituted cycloalkyl having 3-20 ring carbon atoms, substituted or unsubstituted heteroalkyl having 1-20 carbon atoms, substituted or unsubstituted aralkyl having 7-30 carbon atoms, substituted or unsubstituted alkoxy having 1-20 carbon atoms, substituted or unsubstituted aryloxy having 6-30 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, substituted or unsubstituted alkylsilyl groups having 3 to 20 carbon atoms, substituted or unsubstituted arylsilyl groups having 6 to 20 carbon atoms, substituted or unsubstituted amine groups, acyl groups, carbonyl groups, carboxylic acid groups, ester groups, nitrile groups, isonitrile groups, sulfanyl groups, sulfinyl groups, sulfonyl groups, phosphino groups, and combinations thereof having 0 to 20 carbon atoms; Any adjacent substitutions may be optionally linked to form a ring or fused structure.

6. The device according to claim 1 or 5, wherein Z1 and Z2 are S.

7. The device according to claim 1 or 5, wherein X2 and X3 are N.

8. The device according to claim 1 or 5, wherein X2 and X3 are each independently selected from CR, each R may be the same or different, and at least one of the R comprises at least one electron withdrawing group; preferably, each of the R comprises at least one electron withdrawing group.

9. The device of claim 1 or 5, wherein R is selected from the group consisting of fluorine, chlorine, trifluoromethyl, trifluoromethoxy, pentafluoroethyl, pentafluoroethoxy, cyano, nitro, methanesulfonyl, trifluoromethanesulfonyl, trifluoromethylthio, pentafluorothio, pyridyl, 3-fluorophenyl, 4-fluorophenyl, 3-cyanophenyl, 4-cyanophenyl, 4-trifluoromethylphenyl, 3-trifluoromethoxyphenyl, 4-trifluoromethoxyphenyl, 4-pentafluoroethylphenyl, 4-pentafluoroethoxyphenyl, 4-nitrophenyl, 4-methanesulfonylphenyl, 4-trifluoromethanesulfonylphenyl, 3-trifluoromethylthiophenyl, 4-trifluoromethylthiophenyl, 4-pentafluorothiophenyl, pyrimidinyl, 2,6-dimethyl-1,3,5-triazinyl, and combinations thereof.

10. The device according to claim 1 or 5, wherein X and Y are each independently selected from CR"R"'; R" is selected from cyano, and R"' is each independently selected from the group consisting of halogen, nitro, substituted or unsubstituted alkyl having 1-20 carbon atoms, substituted or unsubstituted cycloalkyl having 3-20 ring carbon atoms, substituted or unsubstituted heteroalkyl having 1-20 carbon atoms, substituted or unsubstituted alkenyl having 2-20 carbon atoms, substituted or unsubstituted aryl having 6-30 carbon atoms, substituted or unsubstituted heteroaryl having 3-30 carbon atoms, nitrile, isonitrile, sulfanyl, sulfinyl, sulfonyl, and combinations thereof.

11. The device according to claim 1 or 5, wherein X and Y are each independently selected from CR"R"'; wherein R" and R"' are each independently selected from the group consisting of trifluoromethyl, cyano, pentafluorophenyl, 4-cyano-2,3,5,6-tetrafluorophenyl and pyridyl.

12. An organic layer, wherein the organic layer comprises a compound having Formula 1: in X1, X2, X3, and X4 are each independently selected from CR or N; when X1, X2, X3, and X4 are each independently selected from CR, each R may be the same or different, and at least one of the Rs comprises at least one electron withdrawing group; Z1 and Z2 are each independently selected from O, S, Se, S=O or SO2; X and Y are each independently selected from CR"R"'; R, R", and R'" are each independently selected from the group consisting of hydrogen, deuterium, halogen, nitro, substituted or unsubstituted alkyl having 1-20 carbon atoms, substituted or unsubstituted cycloalkyl having 3-20 ring carbon atoms, substituted or unsubstituted heteroalkyl having 1-20 carbon atoms, substituted or unsubstituted aralkyl having 7-30 carbon atoms, substituted or unsubstituted alkoxy having 1-20 carbon atoms, substituted or unsubstituted aryloxy having 6-30 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, substituted or unsubstituted alkylsilyl groups having 3 to 20 carbon atoms, substituted or unsubstituted arylsilyl groups having 6 to 20 carbon atoms, substituted or unsubstituted amine groups, acyl groups, carbonyl groups, carboxylic acid groups, ester groups, nitrile groups, isonitrile groups, sulfanyl groups, sulfinyl groups, sulfonyl groups, phosphino groups, and combinations thereof having 0 to 20 carbon atoms; Any adjacent substitutions may be optionally linked to form a ring or fused structure.

13. The organic layer according to claim 12, wherein The organic layer is a charge transport layer; preferably, the organic layer is a hole injection layer; more preferably, the organic layer further comprises an arylamine compound.

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