A compound of general formula and uses thereof

Abstract

The present application relates to a novel organic compound, having the following formula (1): R 1 to R 6 each independently selected from one of C1-C20 alkyl, C2-C20 alkenyl, C2-C20 alkynyl, C1-C20 alkoxy, substituted or unsubstituted C6-C30 aryl, substituted or unsubstituted C3-C30 heteroaryl; Ar 1 to Ar 4 each independently selected from one of substituted or unsubstituted C6-C30 arylamino, substituted or unsubstituted C3-C30 heteroarylamino, substituted or unsubstituted C6-C30 aryl, substituted or unsubstituted C3-C30 heteroaryl. The compound of the present application exhibits excellent device performance and stability as a hole transport material in an OLED device. The present application also protects an organic electroluminescent device using the above-mentioned general compound.

Description

[0001] This invention relates to an organic compound, and more particularly to a novel compound material characterized by trifluorenyldiamine. This invention also relates to the application of this compound in organic electroluminescent devices. Background Technology

[0002] Organic light-emitting diode (OLED) display technology has the advantages of self-illumination, high contrast, fast response speed, and high color saturation. In particular, it does not require a backlight, has a simple device structure, a wide operating temperature range, and can achieve flexible display by flexing the substrate. This makes it the next generation display technology after LCD and has gradually shown its broad prospects for commercial application.

[0003] The principle of OLED light emission typically involves applying a bias voltage to the electrodes of an organic electroluminescent device. This applied voltage drives electrons and holes to be injected from the cathode and anode of the device. As electrons and holes are transported to the core light-emitting region via the electron transport layer and hole transport layer, respectively, they meet, recombine, and release energy. This energy is transferred to the organic light-emitting material. Electrons in the material absorb this energy and transition from the ground state to the excited state. Since the excited state is unstable, electrons will transition back to the ground state, releasing energy through light emission and heat release. By manipulating the energy levels between the ground and excited states, different colors of light can be emitted.

[0004] As shown above, to improve the luminous efficiency of the device, it is necessary to transfer as many electrons and holes injected from the two electrodes as possible to the core luminescent region to form recombination and generate excitons, reducing losses during the transmission process. Simultaneously, it is also necessary to balance the transmission speeds of both electrons and holes to prevent them from meeting outside the luminescent region. This requires the introduction of various auxiliary layers to balance carrier transmission, typically including hole injection layers, hole transport layers, electron blocking layers, and electron injection layers. A high-efficiency, long-lifetime organic electroluminescent device is usually the result of optimized device structure and various organic materials. To achieve higher luminous efficiency and longer lifespan with lower operating voltages, researchers have been dedicated to researching and developing new organic electroluminescent materials to obtain higher-performance materials and enable OLED luminescent devices to achieve better operating conditions.

[0005] In OLED devices, hole transport materials can improve the hole transport efficiency and have a significant impact on device performance. The basic requirements for hole materials include: (1) high hole mobility; (2) their highest molecular occupied orbital (HOMO) level must match the functional layer in contact with them to achieve effective hole injection and transport; and (3) suitable thermal stability, requiring the hole material to be deposited into a dense and uniform thin film to prevent pinholes and avoid defects affecting efficiency and lifetime. Therefore, hole materials need to have a high glass transition temperature (T0). g This is conducive to the formation of a stable non-crystalline form. Summary of the Invention

[0006] The compounds described in this invention are suitable for use in electroluminescent devices, such as OLEDs, and are particularly useful as hole transport materials.

[0007] This invention provides a general formula compound having the structural formula shown in formula (1):

[0008]

[0009] In equation (1), m and n are independent integers from 0 to 7;

[0010] R 1 To R 6 They may be the same as or different from each other, and each is independently selected from one of the following: alkyl (C1-C20), alkenyl (C2-C20), alkynyl (C2-C20), alkoxy (C1-C20), substituted or unsubstituted aryl (C6-C30), and substituted or unsubstituted heteroaryl (C3-C30).

[0011] Ar 1 To Ar 4 They may be the same as or different from each other, and each is independently selected from one of the substituted or unsubstituted C6-C30 aryl groups or the substituted or unsubstituted C3-C30 heteroaryl groups;

[0012] When the above groups contain substituents, the substituents are independently selected from one of the following: halogens, C1-C10 alkyl or cycloalkyl groups, C2-C10 alkenyl groups, C1-C6 alkoxy or thioalkoxy groups, C6-C30 arylamino groups, C3-C30 heteroarylamino groups, C6-C30 monocyclic aromatic or fused-ring aromatic groups, and C3-C30 monocyclic heteroaromatic or fused-ring heteroaromatic groups.

[0013] Furthermore, formula (1) can be represented by the following chemical formulas (1-1) to (1-9):

[0014]

[0015]

[0016]

[0017] In the above chemical formulas (1-1) to (1-9), m and n, R 1 To R 6 Ar 1 To Ar 4 The definitions are the same as those in equation (1).

[0018] Furthermore, R 1 To R 6 Each of the following substituents is preferred independently, but not limited to: methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, sec-butyl, tert-butyl, 2-methylbutyl, n-pentyl, sec-pentyl, cyclopentyl, neopentyl, n-hexyl, cyclohexyl, neohexyl, n-heptyl, cycloheptyl, n-octyl, cyclooctyl, 2-ethylhexyl, trifluoromethyl, pentafluoroethyl, 2,2,2-trifluoroethyl, vinyl, propenyl, butenyl, pentenyl, cyclopentenyl, hexenyl, cyclohexenyl, heptenyl, cycloheptenyl, octenyl, cyclooctenyl, ethynyl, propynyl, butynyl, pentyynyl, hexynyl, octyynyl, phenyl, biphenyl, naphthyl, phenanthryl, furanyl, pyridyl, carbazoleyl, or a combination of the above two groups.

[0019] Furthermore, Ar 1 To Ar 4Each of the following substituents is preferred independently, including but not limited to: phenyl, naphthyl, anthracene, benzo[a]anthrayl, phenanthrene, benzo[a]phenanthrene, pyrene, pyryl, peryl, fluoranyl, tetraphenyl, pentaphenyl, benzo[a]pyrene, biphenyl, azophenyl, triphenyl, trimeric phenyl, tetraphenyl, fluorenyl, spirodifluorenyl, dihydrophenanthrene, dihydropyrene, tetrahydropyrene, cis or trans indo[a]fluorenyl, trimerinyl, isotrimericininyl, spirotrimericininyl, spiroisotrimericininyl, furanyl, benzo[a]furanyl, isobenzofuranyl, dibenzo[a]furanyl, thiophene, benzo[a]thiophene, isobenzo[a]thiophene, dibenzo[a]thiophene, pyrroleyl, isoindoleyl, carbazoleyl. Benzocarbazolyl, indocarbazolyl, pyridinyl, quinolinyl, isoquinolinyl, acridineyl, phenanthridineyl, benzo-5,6-quinolinyl, benzo-6,7-quinolinyl, benzo-7,8-quinolinyl, phenothiazinyl, phenothiazinyl, pyrazolyl, indazoleyl, imidazolyl, benzimidazolel, naphthiazolel, phenanthrimidazolel, pyridinimidazolel, pyrazinimidazolel, quinoxalinimidazolel, oxazolyl, benzooxazolyl, naphthiazolel, anthraquinoxazolyl, phenanthrimidazolel, 1,2-thiazolyl, 1,3-thiazolyl, benzothiazolyl, pyridazinyl, benzopyridazinyl Pyrimidinyl, benzopyrimidinyl, quinoxalinyl, 1,5-diazathanel, 2,7-diazapyrene, 2,3-diazapyrene, 1,6-diazapyrene, 1,8-diazapyrene, 4,5-diazapyrene, 4,5,9,10-tetrazaperyl, pyrazinyl, naphthidyl, azacarbazolyl, benzocarbazolyl, phenanthrolinel, 1,2,3-triazolyl, 1,2,4-triazolyl, benzotriazolyl, 1,2,3-oxadiazolyl, 1,2,4-oxadiazolyl, 1,2,5-oxadiazolyl, 1,2,3-thiadiazolyl, 1,2,4-thiadiazolyl, 1,2,5-thiadiazolyl, 1,3,4-thiadiazolyl, 1,3,5-triazinyl One of 1,2,4-triazinyl, 1,2,3-triazinyl, tetrazolyl, 1,2,4,5-tetrazinyl, 1,2,3,4-tetrazinyl, 1,2,3,5-tetrazinyl, purine, pteridinyl, indazinyl, benzothiadiazolyl, or a combination of the above two groups.

[0020] As a preferred example of the novel general formula compound of the present invention, the following representative compounds can be cited:

[0021]

[0022]

[0023]

[0024]

[0025] As another aspect of the invention, the invention also provides the application of the compounds described above in organic electroluminescent devices. The compounds of the invention are preferably used in organic electroluminescent devices as hole transport materials.

[0026] As another aspect of the present invention, the present invention also provides an organic electroluminescent device, comprising a first electrode, a second electrode and a plurality of organic layers inserted between the first electrode and the second electrode, wherein the organic layers contain compounds represented by general formula (1) as described above or by formulas (1-1) to (1-9) as described above.

[0027] Hole transport materials typically require high hole mobility. In OLED devices, besides high hole mobility, these materials must also be able to form dense, uniform, pinhole-free films during high-vacuum deposition. This places demands on the thermal stability of the molecules, generally requiring the material to possess a high glass transition temperature (T0). g To increase the glass transition temperature, common design methods include incorporating cross-linked or star-shaped structures into the molecule, or introducing rigid groups (such as fluorene rings, spirofluorene, phenanthrene, etc.). Furthermore, fluorene possesses a wide band gap and high luminescence efficiency. Attaching large aromatic groups to fluorene can suppress close packing of molecules and the formation of complexes, resulting in compounds with excellent thermal stability and luminescence efficiency.

[0028] The specific reasons for the excellent performance of the above-mentioned compounds as hole transport materials are not yet clear, but it is speculated that the reasons may be as follows:

[0029] The novel compounds designed in this invention improve material performance through careful selection of fluorene group substitution positions and corresponding substituents. The introduction of three fluorene groups significantly enhances the thermal stability of the material. Our research revealed that substitutions at positions 3, 6, 4, and 5 result in relatively higher glass transition temperatures compared to molecules substituted at positions 2 and 7. This may be because molecules substituted at these positions exhibit greater molecular distortion, preventing crystallization and promoting the formation of a stable amorphous morphology, thus increasing material stability. Furthermore, when these compounds are applied to organic electroluminescent devices, their excellent stability contributes to improved device efficiency and lifespan.

[0030] In addition, the preparation process of the compounds of the present invention is simple and easy to implement, the raw materials are readily available, and it is suitable for mass production scale-up. Detailed Implementation

[0031] To enable those skilled in the art to better understand the present invention, the present invention will be further described in detail below with reference to specific embodiments.

[0032] Compounds synthesized using methods not mentioned in this invention are all commercially available raw materials. Various chemicals used in the examples, such as petroleum ether, ethyl acetate, n-hexane, toluene, tetrahydrofuran, dichloromethane, 1,2-bis(bromomethyl)benzene, CuI, phthaloyl chloride, cesium carbonate, potassium phosphate, ethylenediamine, sodium tert-butoxide, 1-bromo-2-methylnaphthalene, o-dibromobenzene, butyllithium, dibromoethane, o-dibromobenzene, N-bromosuccinimide, methoxymethyltrimethylphosphonium chloride, tris(dibenzylideneacetone)dipalladium, tetra(triphenylphosphine)palladium, 1,3-bis(diphenylphosphine propane)nickel chloride, carbazole, 3,6-di-tert-butylcarbazole, N-phenylcarbazole-3-bromo, 2-(4-bromobenzene)-4,6-diphenyltriazine, and other basic chemical raw materials, are all available in the domestic chemical market.

[0033] The intermediates and compounds in this invention were analyzed and detected using an ABSCIEX mass spectrometer (4000QTRAP) and a Bruker nuclear magnetic resonance spectrometer (400M Hz).

[0034] The synthesis method of the compounds of the present invention will be briefly described below.

[0035] The synthetic route of this invention can be represented by the following general formula:

[0036]

[0037] The compounds of the present invention can be synthesized using methods known to those skilled in the art from the prior art, such as by means of halogenation, Buchwald coupling, and Suzuki coupling.

[0038] The scheme shows a preferred synthetic route for preparing the compounds according to the invention. For the synthesis of the compounds according to the invention, the target compound is obtained by reacting the dihalogenated fluorene compound A with the corresponding amine B of Fluorene-NH-Ar and an amine in a Buchwald coupling process.

[0039] X1 and X2 are easily leaving groups, such as halogens, OMs, and OTf.

[0040] The synthetic routes for the starting material compounds A, amine B, and amine C used in the compounds of this invention are known to those skilled in the art.

[0041] More specifically, C1 to C28 can be prepared according to the following representative synthetic methods.

[0042] C3 Synthesis

[0043]

[0044] In a four-necked flask equipped with a condenser, starting compounds (3-1) 3,6-dibromo-9,9-dimethylfluorene (15.0 g, 42.6 mol), (3-2) N-phenyl-2-(9,9-dimethyl-9H-fluorene)amine (26.8 g, 93.7 mmol), sodium tert-butoxide (12.3 g, 127.8 mmol), and toluene (300 mL) were added. The mixture was stirred to dissolve and then completely purged with nitrogen. Pd2(dba)3 (780 mg, 0.852 mmol) and SPhos (2-dicyclohexylphosphine-2',6'-dimethoxybiphenyl) (1.4 g, 3.41 mmol) were then added. Under nitrogen protection, the mixture was heated to reflux and reacted for 20 h. TLC monitoring was continued until the starting materials had completely reacted. The mixture was then cooled to room temperature and extracted with a saturated ammonium chloride solution. The aqueous phase was extracted with toluene (150 mL * 2). The organic phases were combined, washed once more with saturated brine, dried over anhydrous sodium sulfate, filtered, and concentrated to obtain the crude product. The crude product was further purified by silica gel column chromatography to obtain a yellow solid (25 g). Further purification by recrystallization from toluene and ethanol yielded a pale yellow solid (16 g).

[0045] Similarly, by replacing compound (3-2) with other different fluorene arylamines, the corresponding compounds can be obtained.

[0046] More specifically, C29 to C56 can be prepared using the following representative synthetic methods.

[0047] C29 Synthesis

[0048]

[0049] Synthesis of compound 29-3

[0050] In a four-necked flask equipped with a condenser, starting compound (29-1) 2-bromo-7-iodo-9,9-dimethylfluorene (15.0 g, 37.6 mol), starting compound (29-2) N-phenyl-2-(9,9-dimethyl-9H-fluorene)amine, sodium tert-butoxide (4.7 g, 48.9 mmol), and toluene (200 mL) were added. The mixture was stirred to dissolve and then completely purged with nitrogen. Pd2(dba)3 (344 mg, 0.376 mmol) and SPhos (617 mg, 1.5 mmol) were then added. Under nitrogen protection, the mixture was heated to reflux for 20 h, and TLC was monitored until the starting materials had completely reacted. The mixture was then cooled to room temperature and extracted with a saturated ammonium chloride solution. The aqueous phase was extracted with toluene (150 mL * 2). The organic phases were combined, washed once more with saturated brine, dried over anhydrous sodium sulfate, filtered, and concentrated to obtain the crude product. The crude product was further purified by silica gel column chromatography to obtain a yellow solid (17g).

[0051] In a four-necked flask equipped with a condenser, intermediate (29-3) (10.0 g, 18.0 mol), (starting compound (29-4)N-[4-(9-phenanthren-9-yl)phenyl]-2-(9,9-dimethyl-9H-fluorene)amine (9,9-dimethyl-N-(4-(phenanthren-9-yl)phenyl)-9H-fluoren-2-amine(29-4)) (9.1 g, 19.8 mmol), sodium tert-butoxide (2.3 g, 23.4 mmol), and toluene (200 mL) were added. The mixture was stirred to dissolve and then fully purged with nitrogen. Pd2(dba)3 (164 mg, 0.180 mmol) and tri-tert-butylphosphine (50% in) were then added. o-xylene (290 mg, 0.719 mmol). Under nitrogen protection, the mixture was refluxed for 20 h, and TLC was monitored until the reactants had completely reacted. The mixture was then cooled to room temperature and extracted with a saturated ammonium chloride solution. The aqueous phase was extracted with toluene (150 mL * 2). The organic phases were combined, washed once more with saturated brine, dried over anhydrous sodium sulfate, filtered, and concentrated to obtain the crude product. The crude product was further purified by silica gel column chromatography to obtain a yellow solid (10 g). Further recrystallization from toluene and ethanol yielded a pale yellow solid (7.3 g).

[0052] Compounds C57-C84 can be synthesized by referring to the above C3 method, except that the starting material 3,6-dibromo-9,9-dimethylfluorene is replaced with 4,5-dibromo-9,9-dimethylfluorene.

[0053] Compounds C85-C112 can be synthesized by referring to the above-mentioned synthesis of C29, except that the starting material 3-bromo-6-iodo-9,9-dimethylfluorene is replaced with 4-bromo-5-iodo-9,9-dimethylfluorene.

[0054] Device Examples

[0055] Implementation

[0056] An OLED includes a first electrode and a second electrode, and an organic material layer located between the electrodes. This organic material layer can be further divided into multiple regions. For example, the organic material layer may include a hole transport region, a light-emitting layer, and an electron transport region.

[0057] In specific embodiments, a substrate can be used below the first electrode or above the second electrode. The substrate is typically made of glass or polymer material with excellent mechanical strength, thermal stability, water resistance, and transparency. Furthermore, thin-film transistors (TFTs) can also be incorporated into the substrate used for displays.

[0058] The first electrode can be formed by sputtering or depositing the material to be used as the first electrode on a substrate. When the first electrode is used as the anode, transparent conductive oxide materials such as indium tin oxide (ITO), indium zinc oxide (IZO), tin dioxide (SnO2), and zinc oxide (ZnO) and any combination thereof can be used. When the first electrode is used as the cathode, metals or alloys such as magnesium (Mg), silver (Ag), aluminum (Al), aluminum-lithium (Al-Li), calcium (Ca), magnesium-indium (Mg-In), and magnesium-silver (Mg-Ag) and any combination thereof can be used.

[0059] Organic material layers can be formed on electrodes using methods such as vacuum thermal evaporation, spin coating, and printing. The compounds used as organic material layers can be small organic molecules, large organic molecules, polymers, and combinations thereof.

[0060] The hole transport region is located between the anode and the light-emitting layer. The hole transport region can be a single-layer hole transport layer (HTL), including a single-layer hole transport layer containing only one compound and a single-layer hole transport layer containing multiple compounds. The hole transport region can also be a multilayer structure including at least one of a hole injection layer (HIL), a hole transport layer (HTL), and an electron blocking layer (EBL).

[0061] The hole injection layer is located between the anode and the hole transport layer. The hole injection layer can be a single compound material or a combination of multiple compounds. For example, the hole injection layer can be one or more compounds of HT-1 to HT-34 mentioned above, or one or more compounds of HI1 to HI3 mentioned below; it can also be one or more compounds of HT-1 to HT-34 doped with one or more compounds of HI1 to HI3 mentioned below.

[0062]

[0063] The emissive layer includes luminescent dyes (i.e., dopants) that can emit different wavelengths of light, and may also include a host material. The emissive layer can be a monochromatic emissive layer emitting a single color such as red, green, or blue. Multiple monochromatic emissive layers of different colors can be arranged in a planar pattern according to pixel design, or they can be stacked together to form a colored emissive layer. When different colored emissive layers are stacked together, they can be separated from each other or connected to each other. The emissive layer can also be a single colored emissive layer that can simultaneously emit different colors such as red, green, and blue.

[0064] Depending on the technology used, the light-emitting layer material can be various, including fluorescent electroluminescent materials, phosphorescent electroluminescent materials, and thermally activated delayed fluorescence materials. An OLED device can employ a single light-emitting technology or a combination of different technologies. These different light-emitting materials, categorized by technology, can emit light of the same color or different colors.

[0065] In one aspect of the invention, the light-emitting layer employs fluorescent electroluminescence technology. The fluorescent host material of the light-emitting layer may be selected from, but is not limited to, one or more combinations of BFH-1 to BFH-16 listed below.

[0066]

[0067] In one aspect of the invention, the light-emitting layer employs fluorescent electroluminescence technology. The fluorescent dopant of the light-emitting layer may be selected from, but not limited to, one or more combinations of BFD-1 to BFD-12 listed below.

[0068]

[0069]

[0070] In one aspect of the invention, the light-emitting layer employs phosphorescent photoluminescence technology. The main material of the light-emitting layer is selected from, but not limited to, one or more combinations of GPH-1 to GPH-80.

[0071]

[0072]

[0073]

[0074]

[0075] In one aspect of the invention, the light-emitting layer employs phosphorescent photoluminescence technology. The phosphorescent dopant of the light-emitting layer may be selected from, but not limited to, one or more combinations of GPD-1 to GPD-47 listed below.

[0076]

[0077]

[0078] In one aspect of the invention, the light-emitting layer employs phosphorescent photoluminescence technology. The main material of the light-emitting layer is selected from, but not limited to, one or more combinations of RH-1 to RH-31.

[0079]

[0080]

[0081] In one aspect of the invention, the light-emitting layer employs phosphorescent photoluminescence technology. The phosphorescent dopant of the light-emitting layer may be selected from, but not limited to, one or more combinations of RPD-1 to RPD-28 listed below.

[0082]

[0083]

[0084] In one aspect of the invention, the light-emitting layer employs phosphorescent photoluminescence technology. The phosphorescent dopant of the light-emitting layer may be selected from, but not limited to, one or more combinations of YPD-1 to YPD-11 listed below.

[0085]

[0086]

[0087] The OLED organic material layer may also include an electron transport region between the light-emitting layer and the cathode. The electron transport region can be a single-layer electron transport layer (ETL), including single-layer electron transport layers containing only one compound and single-layer electron transport layers containing multiple compounds. Alternatively, the electron transport region can be a multilayer structure including at least one of an electron injection layer (EIL), an electron transport layer (ETL), and a hole blocking layer (HBL).

[0088] In one aspect of the present invention, the electron transport layer material may be selected from, but not limited to, one or more combinations of ET-1 to ET-57 listed below.

[0089]

[0090]

[0091]

[0092] The device may also include an electron injection layer located between the electron transport layer and the cathode, and the electron injection layer material includes, but is not limited to, one or more combinations of the following.

[0093] LiQ, LiF, NaCl, CsF, Li2O, Cs2CO3, BaO, Na, Li, Ca.

[0094] The fabrication process of the organic electroluminescent device in this embodiment is as follows:

[0095] The glass plate coated with the ITO transparent conductive layer was ultrasonically treated in a commercial cleaning agent, rinsed in deionized water, ultrasonically degreased in a acetone:ethanol mixed solvent, baked in a clean environment until all moisture was removed, cleaned with ultraviolet light and ozone, and bombarded with a low-energy cation beam.

[0096] The glass substrate with the anode was placed in a vacuum chamber and evacuated to a vacuum level of 1×10⁻⁶. -5 ~9×10 -3 Pa, HI1 is vacuum-deposited on the above-mentioned anodic layer as a hole injection layer at a deposition rate of 0.1 nm / s and a film thickness of 10 nm.

[0097] HT-2 was vacuum-deposited on top of the hole injection layer as the hole transport layer of the device at a deposition rate of 0.1 nm / s and a total film thickness of 80 nm.

[0098] The light-emitting layer of the device is vacuum-deposited on top of the hole transport layer. The light-emitting layer includes a host material and a dye material. Using a multi-source co-evaporation method, the evaporation rate of the host material BFH-2 is adjusted to 0.1 nm / s, the evaporation rate of the dye BFD-3 is set to 3%, and the total film thickness is 30 nm.

[0099] The electron transport layer material ET-56 of the device is vacuum-deposited on the light-emitting layer at a deposition rate of 0.1 nm / s and a total film thickness of 30 nm.

[0100] A 0.5 nm thick LiF layer was vacuum-deposited on the electron transport layer (ETL) as the electron injection layer, and a 150 nm thick Al layer was used as the cathode of the device.

[0101] In the organic electroluminescent devices prepared by the present invention, the devices in Examples 1 to 8 were prepared by using the compounds of the present invention as hole transport materials in the devices, and the devices in Comparative Examples 1, 2, 3 and 4 were prepared by using the prior art compounds HT-2, HT-33 and HT35, respectively.

[0102]

[0103]

[0104] Comparative Example 1

[0105] An organic electroluminescent device was obtained according to the above device fabrication method, using the existing compound HT-2 as the hole transport material.

[0106] Comparative Example 2

[0107] Organic electroluminescent devices were prepared using the same method as in Comparative Example 1, except that compound HT-2 was replaced with compound HT-33 from the prior art.

[0108] Comparative Example 3

[0109] Organic electroluminescent devices were prepared using the same method as in Comparative Example 1, except that compound HT-2 was replaced with compound HT-35 from the prior art.

[0110] Device Example 1

[0111] Organic electroluminescent devices were prepared using the same method as in Comparative Example 1, except that HT-2 was replaced with compound C1 synthesized in this invention.

[0112] Device Example 2

[0113] Organic electroluminescent devices were prepared using the same method as the comparative example, except that HT-2 was replaced with compound C6 synthesized in this invention.

[0114] Device Example 3

[0115] Organic electroluminescent devices were prepared using the same method as the comparative example, except that HT-2 was replaced with compound C8 synthesized in this invention.

[0116] Device Example 4

[0117] Organic electroluminescent devices were prepared using the same method as the comparative example, except that HT-2 was replaced with compound C15 synthesized in this invention.

[0118] Device Example 5

[0119] Organic electroluminescent devices were prepared using the same method as the comparative example, except that HT-2 was replaced with compound C36 synthesized in this invention.

[0120] Device Example 6

[0121] Organic electroluminescent devices were prepared using the same method as the comparative example, except that HT-2 was replaced with compound C23 synthesized in this invention.

[0122] Device Example 7

[0123] Organic electroluminescent devices were prepared using the same method as the comparative example, except that HT-2 was replaced with compound C32 synthesized in this invention.

[0124] Device Example 8

[0125] Organic electroluminescent devices were prepared using the same method as the comparative example, except that HT-2 was replaced with compound C1 synthesized in this invention; and the host material and dye material in the light-emitting layer were replaced with RH-1 and RPD-2, respectively.

[0126] Device Comparison Example 4

[0127] Organic electroluminescent devices were prepared using the same method as the comparative example, with compound HT-2 from the prior art used as the hole transport material; the host material and dye material in the light-emitting layer were replaced with RH-1 and RPD-2, respectively.

[0128] Device testing methods (including equipment and testing conditions):

[0129] The organic electroluminescent devices prepared by the above process were subjected to the following performance measurements:

[0130] Under the same brightness, the driving voltage, current efficiency, and lifetime of the organic electroluminescent devices prepared in Examples 1-7 and Comparative Examples 1-3 were measured using a digital source meter and a luminance meter. Specifically, the voltage was increased at a rate of 0.1V per second, and the measurement was performed when the brightness of the organic electroluminescent device reached 1000 cd / m². 2 The voltage at that time is the driving voltage, and the current density at that time is measured simultaneously; the ratio of brightness to current density is the current efficiency; the life test of LT95 is as follows: using a luminance meter at 1000 cd / m² 2 Under constant current, the time it takes for the brightness of an organic electroluminescent device to drop to 95% is measured in hours.

[0131] The performance results of the organic electroluminescent devices prepared in the above embodiments and comparative examples are shown in Table 1 below.

[0132] Table 1:

[0133]

[0134]

[0135] At the same brightness, the driving voltage and current efficiency, as well as the lifetime of the organic electroluminescent devices prepared in Example 8 and Comparative Example 4, were measured using a digital source meter and a luminance meter. Specifically, the voltage was increased at a rate of 0.1V per second, and the measurement was performed when the brightness of the organic electroluminescent device reached 5000 cd / m². 2 The voltage at that time is the driving voltage, and the current density at that time is measured simultaneously; the ratio of brightness to current density is the current efficiency; the life test of LT98 is as follows: using a luminance meter at 5000 cd / m² 2Under constant current, the time it takes for the brightness of an organic electroluminescent device to drop to 98% is measured in hours.

[0136] Table 2:

[0137] Example number Compound numbering <![CDATA[Required brightness cd / m 2 > Voltage V Current efficiency cd / A Lifespan LT98(h) Example 8 Compound C1 5000.00 5.4 16.62 59 Comparative Example 4 HT-2 5000.00 5.9 14.81 31

[0138] The above results show that the novel organic material of the present invention, when used in organic electroluminescent devices, can effectively reduce the start-up and drop voltage and improve current efficiency, and is a high-performance hole transport material.

[0139] Although the invention has been described in conjunction with embodiments, the invention is not limited to the above embodiments. It should be understood that various modifications and improvements can be made by those skilled in the art under the guidance of the inventive concept, and the appended claims summarize the scope of the invention.

[0140] Obviously, the above embodiments are merely illustrative examples for clear explanation and are not intended to limit the implementation. Those skilled in the art will recognize that other variations or modifications can be made based on the above description. It is neither necessary nor possible to exhaustively list all possible implementations here. However, obvious variations or modifications derived therefrom are still within the scope of protection of this invention.

Claims

1. A compound of a general formula having a structure as shown in formulas (1-7) or (1-9): Equation (1-7) Equation (1-9) in: m and n are both independently 0; R 1 To R 6 It is methyl; Ar 1 Ar 2 Each of the following substituents is independently selected: phenyl, naphthyl, anthracene, phenanthrene, biphenyl, dibenzofuranyl, dibenzothiophene, carbazoleyl; When the above groups contain substituents, the substituents are each independently selected from methyl and phenyl.

2. Compounds having the following structures: 。 3. The application of the compound of the general formula according to claim 1, wherein the application is as a hole transport material in an organic electroluminescent device.

4. The application of the structural compound of claim 2, wherein the application is as a hole transport material in an organic electroluminescent device.

5. An organic electroluminescent device, comprising a first electrode, a second electrode, and one or more organic layers inserted between the first electrode and the second electrode, characterized in that, The organic layer includes at least one compound as described in claim 1.

6. An organic electroluminescent device, comprising a first electrode, a second electrode, and one or more organic layers inserted between the first electrode and the second electrode, characterized in that, The organic layer includes at least one compound as described in claim 2.

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