Organic compound having a large conjugated structure, organic electroluminescent device

Abstract

The present application relates to organic compound with large conjugated structure, organic electroluminescence device. Specifically provide an organic compound, it is structure shown in formula (1): The compound provided by the present application is the main body material of large plane polycyclic, so that under the premise of ensuring the original large plane system triplet energy level unchanged, further expand the planar type of molecular structure, further enhance the carrier transport performance and stability of the compound, applied to organic electroluminescence device, can make the device have more excellent performance, such as lower voltage, higher efficiency and longer device life.

Description

Technical Field

[0001] This invention relates to a compound for use in organic electronic devices, and particularly to an organic optoelectronic material having a highly conjugated structure. The invention also relates to the application of such materials in organic electroluminescent devices. Background Technology

[0002] In recent years, optoelectronic devices based on organic materials have developed rapidly and become a research hotspot in the field. Examples of such organic optoelectronic devices include organic light-emitting diodes (OLEDs), organic field-effect transistors, organic photovoltaic cells, and organic sensors. Among them, OLEDs have developed particularly rapidly and have already achieved commercial success in the field of information display. OLEDs can provide highly saturated red, green, and blue colors, and full-color display devices made with them do not require an additional backlight, offering advantages such as vibrant colors, thinness, and flexibility.

[0003] The core of an OLED device is a multilayer thin-film structure containing various organic functional materials. Common functionalized organic materials include: hole injection materials, hole transport materials, hole blocking materials, electron injection materials, electron transport materials, electron blocking materials, as well as light-emitting host materials and light-emitting guest materials (dyes). When an electric current is applied, electrons and holes are injected and transported to the light-emitting region, where they recombine, thereby generating excitons and emitting light.

[0004] Common phosphors primarily utilize singlet excitons generated when electrons and holes combine to emit light, and are still widely used in various OLED products. Some metal complexes, such as iridium complexes, can simultaneously utilize both triplet and singlet excitons to emit light; these are called phosphors, and their energy conversion efficiency can be up to four times higher than that of traditional phosphors. Thermally excited delayed fluorescence (TADF) technology promotes the conversion of triplet excitons to singlet excitons, achieving high luminous efficiency without the use of metal complexes, while still effectively utilizing triplet excitons. Thermally excited sensitized fluorescence (TASF) technology uses materials with TADF properties to sensitize the phosphor through energy transfer, also achieving high luminous efficiency.

[0005] Although products using OLED display technology are already commercialized, there is still a need to continuously improve the lifespan, efficiency, and other performance characteristics of these devices to meet people's demands for higher quality. Therefore, there is an urgent need in this field to develop a wider variety of organic materials for use in organic electroluminescent devices, enabling these devices to achieve higher luminous efficiency, lower driving voltage, and longer lifespan.

[0006] Developing novel host materials is a common way to improve device efficiency. CN110268037A discloses a class of host materials.

[0007]

[0008] However, there is still much room for improvement in the luminescent properties of this type of host material. Therefore, there is an urgent need in this field to develop more types of organic materials for use in organic electroluminescent devices, enabling the devices to have higher luminous efficiency, lower driving voltage, and longer lifespan. Summary of the Invention

[0009] To solve the above-mentioned technical problems, the inventors of this invention, through in-depth research, have found an organic electroluminescent material, which is the following organic compound. When used as the main material in organic electroluminescent devices, it can reduce the excitation voltage, improve the current efficiency, and significantly extend the device life.

[0010] Specifically, the present invention provides an organic compound, characterized in that it has the structure shown in formula (1):

[0011]

[0012] The dashed lines represent single bonds or the absence of bonds.

[0013] X 1 ~X 10 For CR 1 Or N; R 1 Independently selected from one of hydrogen, halogen, cyano, nitro, hydroxyl, amino, substituted or unsubstituted C1-C20 alkyl, substituted or unsubstituted C1-C20 alkoxy, substituted or unsubstituted C1-C20 silyl, substituted or unsubstituted C6-C60 arylamino, substituted or unsubstituted C3-C60 heteroarylamino, substituted or unsubstituted C6-C60 aryl, substituted or unsubstituted C3-C60 heteroaryl, wherein R 1 It can independently connect with connected aromatic or heteroaromatic rings to form a ring or not connect to form a ring;

[0014] Y 1 Y is O, S, or does not exist. 2 Y is O, S, or does not exist. 1 and Y 2 They do not exist simultaneously.

[0015] When Y 1 When Y is O or S, 2 Does not exist, X 12 X 17 For C atoms, Y 1 With X 12 Connected by a single key, Y 1 With X 17 Connected with a single key, X 13 ~X 16 One of them is CR2 The rest are CH, X 11 For CR 1 ;

[0016] When Y 2 When Y is O or S, 1 Does not exist, X 11 X 13 For C atoms, Y 2 With X 11 Connected by a single key, Y 2 With X 13 Connected with a single key, X 14 ~X 17 One of them is CR 2 The rest are CH, X 12 For CR 1 ;

[0017] The R 2 For the structure shown in equation (a) or (b), * represents the connection position with the parent core;

[0018]

[0019] Z is either O or S;

[0020] Ar is one of substituted or unsubstituted C6-C60 aryl or substituted or unsubstituted C3-C60 heteroaryl;

[0021] R 3 There are n, where n is an integer from 1 to 4. When n ≥ 2, there are different R... 3 They can form a ring with each other, and the R 3 It is independently selected from one of hydrogen, halogen, cyano, nitro, hydroxyl, amino, substituted or unsubstituted C1-C20 alkyl, substituted or unsubstituted C1-C20 alkoxy, substituted or unsubstituted C1-C20 silyl, substituted or unsubstituted C6-C60 arylamino, substituted or unsubstituted C3-C60 heteroarylamino, substituted or unsubstituted C6-C60 aryl, and substituted or unsubstituted C3-C60 heteroaryl.

[0022] The "—" dashed representation of a ring structure indicates that the connection point is located at any bondable position within the ring structure.

[0023] The substitution or non-substitution in the above-mentioned groups refers to being replaced by one or a combination of at least two of the following: halogen, C1-C20 alkyl, C1-C20 alkoxy, C1-C20 silyl, cyano, nitro, hydroxyl, amino, C6-C30 arylamino, C3-C30 heteroarylamino, C6-C30 aryloxy, C3-C30 heteroaryloxy, C6-C60 aryl, and C3-C60 heteroaryl. The substituent may be independently linked to or not linked to the connected aromatic or heteroaryl ring to form a ring.

[0024] The host material reported in patent document CN110268037A has a π-conjugated core that limits its transport performance. In this invention, the host structure of formula (1) is used, and the compound provided by this invention is a large-planar polycyclic host material, wherein Y... 1 Or Y 2 Through its main atom and X 11 or X 12 The formation of a non-conjugated six-membered ring further expands the planarity of the molecular structure while ensuring that the triplet energy levels of the original large planar system are not significantly reduced, thus further enhancing the transport performance of the compound. The introduction of the six-membered ring also makes the HOMO energy levels of the material shallower, improving its injection capability and resulting in a lower light-on voltage and operating voltage for the material of this invention. Furthermore, the substituent R in this invention... 2 It is also very crucial, R 2 A better match with the parent nucleus in energy levels further improves carrier transport efficiency, and R 2 The size and configuration of the material are suitable, which is beneficial for the transport of charge carriers between molecules during the molecular film formation process. Furthermore, the preferred electron-deficient group in this invention has a relatively rigid structure, and its excellent electron transport performance perfectly meets the requirements of this invention, balancing molecular holes and electron transport. Moreover, this type of material can form thin films with few traps and high density. Therefore, this invention, through the aforementioned special core and special substituents containing heteroatoms, can achieve very good charge carrier transport efficiency, making it particularly suitable as a host material for luminescent layers, especially for red light.

[0025] It should be noted that in this specification, the expression Ca to Cb represents the number of carbon atoms in the group as a to b. Unless otherwise specified, this number of carbon atoms generally does not include the number of carbon atoms in the substituents. In this invention, the description of chemical elements, unless otherwise specified, usually includes the concept of isotopes with the same chemical properties. For example, the description of "hydrogen" also includes the concepts of "deuterium" and "tritium" with the same chemical properties, and carbon (C) includes... 12 C 13 C, etc., will not be elaborated further.

[0026] In the structural formulas disclosed in this specification, the way the ring structure is represented by "—" indicates that the connection point is located at any position on the ring structure where bonding can occur.

[0027] In this invention, the term "heteroaryl" refers to an aromatic cyclic group containing heteroatoms. Heteroatoms are usually selected from N, O, S, P, Si, and Se, and are preferably selected from N, O, and S.

[0028] Unless otherwise specified, the C6-C60 aryl and C3-C60 heteroaryl groups mentioned above in this invention are aromatic groups that satisfy the π-conjugated system, including both monocyclic and fused ring types. A monocyclic molecule refers to a molecule containing at least one phenyl group. When a molecule contains at least two phenyl groups, the phenyl groups are independent of each other and connected by single bonds, such as phenyl, diphenyl, and triphenyl. A fused-ring molecule refers to a molecule containing at least two benzene rings, but the benzene rings are not independent of each other; instead, they are fused together by sharing ring edges, such as naphthyl, anthracene, and phenanthrene. A monocyclic heteroaryl molecule refers to a molecule containing at least one heteroaryl group. When a molecule contains one heteroaryl group and other groups (such as aryl, heteroaryl, alkyl, etc.), the heteroaryl group and other groups are independent of each other and connected by single bonds, such as pyridine, furan, and thiophene. A fused-ring heteroaryl molecule refers to a molecule formed by the fusion of at least one phenyl group and at least one heteroaryl group, or by the fusion of at least two heteroaryl groups, such as quinoline, isoquinoline, benzofuran, dibenzofuran, benzothiophene, and dibenzothiophene.

[0029] In this specification, the substituted or unsubstituted C6-C60 aryl groups are preferably C6-C30 aryl groups. The number of carbon atoms in the aryl group includes, but is not limited to, C6, C8, C10, C12, C14, C16, C18, C20, C22, C24, C26, C28, etc. Exemplarily preferred are aryl groups from the group consisting of phenyl, naphthyl, anthracene, benzo[a]anthrayl, phenanthrene, benzo[a]phenanthrene, pyrene, pyrene, peryl, fluoranyl, tetraphenyl, pentaphenyl, benzo[a]pyrene, biphenyl, azophenyl, terphenyl, triphenyl, tetraphenyl, fluorenyl, spirodifluorenyl, dihydrophenanthrene, dihydropyrene, tetrahydropyrene, cis or trans indo[a]fluorenyl, trimenyl, isotrimeric indo[a], spirotrimeric indo[a], and spiroisotrimeric indo[a] Specifically, the biphenyl group is selected from 2-biphenyl, 3-biphenyl, and 4-biphenyl; the terphenyl group includes p-terphenyl-4-yl, p-terphenyl-3-yl, p-terphenyl-2-yl, meta-terphenyl-4-yl, meta-terphenyl-3-yl, and meta-terphenyl-2-yl; the naphthyl group includes 1-naphthyl or 2-naphthyl; the anthracene group is selected from 1-anthrayl, 2-anthrayl, and 9-anthrayl; the fluorenyl group is selected from 1-fluorenyl, 2-fluorenyl, 3-fluorenyl, 4-fluorenyl, and 9-fluorenyl; the pyrene group is selected from 1-pyrene, 2-pyrene, and 4-pyrene; and the tetraphenyl group is selected from 1-tetraphenyl, 2-tetraphenyl, and 9-tetraphenyl. Preferred examples of aromatic rings in this invention include those composed of phenyl, biphenyl, terphenyl, naphthyl, anthracene, phenanthryl, indene, fluorenyl and their derivatives, fluoranyl, triphenylene, pyrene, perylene, etc. The group is selected from the group consisting of 1-triphenyl-4-yl, 3-triphenyl-3-yl, 2-triphenyl-2-yl, 4-triphenyl-3-yl, 3-triphenyl-4-yl, 3-triphenyl-3-yl, and 3-triphenyl-2-yl; the naphthyl group includes 1-naphthyl or 2-naphthyl; the anthracene group is selected from the group consisting of 1-anthrayl, 2-anthrayl, and 9-anthrayl. The fluorenyl group is selected from the group consisting of 1-fluorenyl, 2-fluorenyl, 3-fluorenyl, 4-fluorenyl, and 9-fluorenyl; the fluorenyl derivative is selected from the group consisting of 9,9-dimethylfluorenyl, 9,9-spirodifluorenyl, and benzo[a]fluorenyl; the pyrene group is selected from the group consisting of 1-pyrene, 2-pyrene, and 4-pyrene; the tetraphenyl group is selected from the group consisting of 1-tetraphenyl, 2-tetraphenyl, and 9-tetraphenyl. The C6-C60 aryl groups of this invention can also be groups formed by single-bonded or / and fused combinations of the above groups.

[0030] In this specification, the substituted or unsubstituted C3-C60 heteroaryl groups are preferably C3-C30 heteroaryl groups. In this invention, the number of carbon atoms in the heteroaryl group includes, but is not limited to, C4, C5, C6, C8, C10, C12, C14, C16, C18, C20, C22, C24, C26, C28, etc., and can be nitrogen-containing heteroaryl, oxygen-containing heteroaryl, sulfur-containing heteroaryl, etc. Specific examples include: furanyl, thiophene, pyrrole, pyridyl, benzofuranyl, benzothiophene, isobenzofuranyl, iso... Benzothiophene, indolyl, isoindolyl, dibenzofuranyl, dibenzothiophene, carbazole and its derivatives, quinolinyl, isoquinolinyl, acridineyl, phenanthridineyl, benzo-5,6-quinolinyl, benzo-6,7-quinolinyl, benzo-7,8-quinolinyl, phenthiazinyl, phenazinyl, pyrazolyl, indazoleyl, imidazolyl, benzimidazole, naphthomidazole, phenanthrenemidazole, pyridiniumimidazolyl, pyraziniumimidazolyl, quinoxaliniumimidazolyl, oxazolyl, benzooxazolyl, naphthooxazolyl, anthraquinoxazolyl, phenanthreneoxazolyl 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-tetraazaperyl, pyrazinyl, phenazinyl, phenthiazinyl, naphridinyl, azacarbazolyl, benzocarbalinyl, phenanthrolinel, 1,2,3-triazolyl, 1,2,4-triazolyl Azolyl, 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, 1,2,4-triazinyl, 1,2,3-triazinyl, tetrazolyl, 1,2,4,5-tetrazinyl, 1,2,3,4-tetrazinyl, 1,2,3,5-tetrazinyl, purinyl, pteridineyl, indazinyl, benzothiadiazole, etc. Preferred examples of heterocycles in this invention include furanyl, thiopheneyl, pyrroleyl, benzofuranyl, benzothiopheneyl, isobenzofuranyl, indolyl, dibenzofuranyl, dibenzothiopheneyl, carbazoleyl, and their derivatives. The carbazoleyl derivative is preferably 9-phenylcarbazole, 9-naphthylcarbazole, benzocarbazole, dibenzocarbazole, or indolocarbazole. The C3-C60 heteroaryl groups of this invention can also be groups formed by single-bonded or / and fused combinations of the above groups.

[0031] In this specification, unless otherwise specified, alkyl groups include straight-chain alkyl groups, branched alkyl groups, and cycloalkyl groups. The number of carbon atoms in an alkyl group includes, but is not limited to, C1, C2, C3, C4, C5, C6, C7, C8, C9, C10, C11, C12, C13, C14, C15, C16, C17, C18, C19, C20, C22, C24, C26, and C28. As C1 to C30 alkyl groups, C1 to C20 alkyl groups are further preferred, and examples include: methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, sec-butyl, tert-butyl, 2-methylbutyl, n-pentyl, sec-pentyl, cyclopentyl, neopentyl, n-hexyl, cyclohexyl, adamantyl, neohexyl, n-heptyl, cycloheptyl, n-octyl, cyclooctyl, 2-ethylhexyl, trifluoromethyl, pentafluoroethyl, 2,2,2-trifluoroethyl, etc., and even more preferably C1 to C10 alkyl groups.

[0032] In this specification, cycloalkyl includes monocycloalkyl and polycycloalkyl, and the number of carbon atoms includes, but is not limited to, C4, C5, C6, C7, C8, C9, etc., for example: cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, cycloheptyl, etc.

[0033] Examples of C1 to C20 alkoxy groups in this specification include: methoxy, ethoxy, n-propoxy, isopropoxy, n-butoxy, sec-butoxy, isobutoxy, tert-butoxy, pentooxy, isopentoxy, hexoxy, heptoxy, octoxy, nonoxy, decoxy, undecoxy, dodecoxy, etc., with methoxy, ethoxy, n-propoxy, isopropoxy, tert-butoxy, sec-butoxy, isobutoxy, isopentoxy, and more preferably methoxy.

[0034] In this specification, examples of C1 to C20 silanes can be silanes substituted with groups listed in the above C1 to C20 silanes, specifically including: methylsilane, dimethylsilane, trimethylsilane, ethylsilane, diethylsilane, triethylsilane, tert-butyldimethylsilane, tert-butyldiphenylsilane, etc.

[0035] In this specification, as C6 to C60 aryloxy groups, examples can be made by attaching each of the substituted or unsubstituted C6 to C60 aryl groups to oxygen. Specific examples can be found in the examples above, and will not be repeated here.

[0036] Examples of halogens in this specification include fluorine, chlorine, bromine, and iodine.

[0037] In this specification, C6-C60 arylamino and C3-C60 heteroarylamino refer to groups obtained by replacing one or both H atoms of the amino-NH2 group with the C6-C60 aryl or C3-C60 heteroaryl groups exemplified above.

[0038] In this invention, as a preferred embodiment, the structure shown in formula (1) is preferably the structure shown in formula (2):

[0039]

[0040] Where Y 1 For O or S, X 1 ~X 17 The meaning is the same as above.

[0041] In this invention, the structure shown in formula (1) can also preferably be the structure shown in formula (3).

[0042]

[0043] Where Y 2 For O or S, X 1 ~X 17 The meaning is the same as above.

[0044] In a preferred embodiment of the present invention, X 1 ~X 10 0 to 2 of them are N, and the rest are CR. 1 R 1 Independently selected from one of hydrogen, halogen, cyano, nitro, hydroxyl, amino, C1-C20 alkyl, C1-C20 alkoxy, C6-C30 aryl, and C3-C30 heteroaryl, wherein R 1 It may independently connect with an associated aromatic ring or heteroaromatic ring to form a ring, or it may not connect to form a ring. X 1 ~X 10 Too much nitrogen hybridization can lead to significant changes in electron-withdrawing properties, resulting in an imbalance in carrier transport. X is preferred. 1 ~X 10 None of them are N, that is, the preferred values ​​are all CR. 1 Among them, R is preferred. 1 The R is independently selected from one of hydrogen, C1-C20 alkyl, and C1-C20 alkoxy. 1 It can be independently linked to an aromatic ring or heteroaromatic ring to form a ring, or it can remain unlinked to form a ring.

[0045] In this invention, in formulas (a) and (b), Z being either O or S has good effects; Ar is further preferably one of substituted or unsubstituted C6-C30 aryl or substituted or unsubstituted C3-C30 heteroaryl, and the substituent of the Ar group is one of C1-C10 alkyl, C1-C10 alkoxy, C6-C20 aryl, and C3-C20 heteroaryl. As a further preferred example of Ar, one can be selected from substituted or unsubstituted phenyl, naphthyl, biphenyl, substituted or unsubstituted naphthyl, substituted or unsubstituted phenanthryl, substituted or unsubstituted anthracene, substituted or unsubstituted benzofuranyl, substituted or unsubstituted dibenzofuranyl, substituted or unsubstituted benzothiophene, substituted or unsubstituted dibenzothiophene, substituted or unsubstituted fluorenyl, substituted or unsubstituted biphenyl, substituted or unsubstituted fluoranyl, and the substituent of Ar is selected from C1-C10 alkyl, C1-C10 alkoxy, C6-C20 aryl, and C3-C20 heteroaryl.

[0046] Ar is preferably composed of one of the following groups: phenyl, naphthyl, biphenyl, anthracene, terphenyl, triphenylene, phenanthryl, carbazole, dibenzothiophene, dibenzofuranyl, 9,9-dimethylfluorenyl, benzothiophene, benzofuranyl, benzocarbazole, and fluoranthyl. These groups can all have substituents. Preferred substituents for Ar include methyl, isopropyl, tert-butyl, cyclohexyl, and phenyl.

[0047] In this invention, R 3 There can be one or more, and when n≥2 they can form a ring with each other, preferably the R. 3 It is one of hydrogen, substituted or unsubstituted C1-C20 alkyl, C1-C20 alkoxy, C6-C30 aryl, and C3-C30 heteroaryl. Further preferred is the R... 3 It is hydrogen.

[0048] In a preferred embodiment of the present invention, the structure shown in formula (a) is selected from the following structures:

[0049]

[0050]

[0051] In a preferred embodiment of the present invention, the structure shown in formula (b) is selected from the following structures:

[0052]

[0053] .

[0054] Furthermore, the organic compounds of the present invention can preferably be compounds with the specific structures shown below. These compounds are merely representative and do not limit the scope of the present invention:

[0055]

[0056]

[0057]

[0058]

[0059]

[0060]

[0061]

[0062]

[0063]

[0064]

[0065]

[0066]

[0067]

[0068]

[0069]

[0070]

[0071]

[0072]

[0073]

[0074]

[0075] When the compounds of the present invention are used as the main material, they have the following advantages over the prior art:

[0076] The compound provided by this invention is a large-planar polycyclic host material, wherein, through Y 1 Or Y 2This allows the benzene rings connected to the N atoms to fuse with the parent nucleus, forming a non-conjugated six-membered ring. This further expands the planarity of the molecular structure while ensuring that the triplet energy levels of the original large planar system remain unchanged, thus further enhancing the transport performance of the compound and giving it superior properties, such as lower voltage, higher efficiency, and longer device lifetime. It is particularly suitable as a host material for the light-emitting layer, especially for red light.

[0077] A second objective of this invention is to provide an application of the compound described in one objective, wherein the compound is used in organic electronic devices.

[0078] Preferably, the organic electronic device includes an organic electroluminescent device, an optical sensor, a solar cell, a lighting element, an organic thin-film transistor, an organic field-effect transistor, an organic thin-film solar cell, an information tag, an electronic artificial skin sheet, a sheet-type scanner, or electronic paper.

[0079] Preferably, the compound is applied to an organic electroluminescent device, and more preferably to a red-light organic electroluminescent device.

[0080] Preferably, the compound is used as the host material of the organic electroluminescent device, and more preferably as the host material for red light.

[0081] A third objective of this invention is to provide an organic electroluminescent device, the organic electroluminescent device comprising a first electrode, a second electrode, and an organic layer inserted between the first electrode and the second electrode, the organic layer comprising at least one of the compounds described in one of the objectives.

[0082] Preferably, the organic layer includes a light-emitting layer containing at least one of the compounds described in one of the objectives.

[0083] Preferably, the light-emitting layer comprises a host material and a dopant material, wherein the host material comprises at least one of the compounds described in one of the objectives.

[0084] Preferably, the host material comprises a first host material and a second host material, wherein at least one of the first host material and the second host material comprises a compound described in at least one of the objectives. The compounds of the present invention, when applied to dual-host devices, can effectively improve device performance.

[0085] OLED devices prepared using the compounds of this invention have low start-up voltage, high luminous efficiency, and better lifespan, which can meet the current requirements of panel and display manufacturers for high-performance materials.

[0086] The compounds disclosed in this invention can be used as host materials, electron transport materials, and hole blocking materials, and are suitable for OLED devices, effectively improving device performance. Their excellent carrier transport performance and high luminous efficiency have potential applications in addressing the efficiency roll-off of OLED devices at high current densities and extending device lifetime.

[0087] OLED devices typically include a first electrode and a second electrode, as well as 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.

[0088] 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.

[0089] In this invention, the first electrode and the second electrode are respectively an anode and a cathode. For example, the first electrode is an anode and the second electrode is a cathode, or the first electrode is a cathode and the second electrode is an anode.

[0090] The first electrode can be formed by sputtering or depositing the material used as the first electrode on a substrate. When the first electrode is used as the anode, it can be a transparent conductive oxide material such as indium tin oxide (ITO), indium zinc oxide (IZO), tin dioxide (SnO2), zinc oxide (ZnO), or any combination thereof. When the first electrode is used as the cathode, it can be a metal or alloy such as magnesium (Mg), silver (Ag), aluminum (Al), aluminum-lithium (Al-Li), calcium (Ca), ytterbium (Yb), magnesium-indium (Mg-In), magnesium-silver (Mg-Ag), or any combination thereof.

[0091] Organic layers can be formed on electrodes using methods such as vacuum thermal evaporation, spin coating, and printing. Compounds used as organic layers can be small organic molecules, large organic molecules, polymers, and combinations thereof.

[0092] 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).

[0093] The material for the hole transport region may be selected from, but is not limited to, phthalocyanine derivatives such as CuPc, conductive polymers or polymers containing conductive dopants such as polyphenylene ethylene, polyaniline / dodecylbenzenesulfonic acid (Pani / DBSA), poly(3,4-ethylenedioxythiophene) / poly(4-styrenesulfonate) (PEDOT / PSS), polyaniline / camphorsulfonic acid (Pani / CSA), polyaniline / poly(4-styrenesulfonate) (Pani / PSS), aromatic amine derivatives, wherein the aromatic amine derivatives include compounds shown below HT-1 to HT-51; or any combination thereof.

[0094]

[0095]

[0096]

[0097] 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-51 described above, or one or more compounds of HI-1 to HI-3 described below; it can also be one or more compounds of HT-1 to HT-51 doped with one or more compounds of HI-1 to HI-3 described below.

[0098]

[0099] In one aspect of the present invention, an electron blocking layer (EBL) is located between the hole transport layer and the light-emitting layer. The electron blocking layer may employ, but is not limited to, one or more compounds of HT-1 to HT-51 described above, or one or more compounds of PH-47 to PH-77 described below; or a mixture of one or more compounds of HT-1 to HT-51 and one or more compounds of PH-47 to PH-77 may be employed.

[0100]

[0101]

[0102] 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.

[0103] 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.

[0104] 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.

[0105]

[0106] The electron transport region can be a single-layer electron transport layer (ETL), including a single-layer electron transport layer containing only one compound and a single-layer electron transport layer containing multiple compounds. The electron transport region can also 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).

[0107] 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-73 listed below.

[0108]

[0109]

[0110]

[0111]

[0112] In one aspect of the present invention, a hole blocking layer (HBL) is located between the electron transport layer and the light-emitting layer. The hole blocking layer may employ, but is not limited to, one or more compounds of ET-1 to ET-73 described above, or one or more compounds of PH-1 to PH-46 described below; or a mixture of one or more compounds of ET-1 to ET-73 and one or more compounds of PH-1 to PH-46 may be employed.

[0113]

[0114]

[0115]

[0116] 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.

[0117] Liq, LiF, NaCl, CsF, Li2O, Cs2CO3, BaO, Na, Li, Ca, Yb.

[0118] The cathode is a mixture of magnesium and silver, LiF / Al, ITO and other metals, metal mixtures and oxides. Detailed Implementation

[0119] The technical solution of the present invention will be further described in more detail below. Those skilled in the art should understand that the specific embodiments and examples described are merely illustrative of the present invention and should not be considered as specific limitations thereof.

[0120] Obtaining the compounds of the present invention

[0121] The representative synthetic routes of the compounds of general formula I provided by this invention are as follows:

[0122]

[0123] Specifically, the key aspect of this invention is the synthesis of the following intermediates M1-M16:

[0124]

[0125] The synthesis of intermediate M1 can be achieved, for example, through the following operations, but is not limited to the following methods:

[0126] 0.5 mol of 3-fluoro-1-naphthoic acid, 0.6 mol of 2,3-dichloronitrobenzene, 0.6 mol of potassium carbonate, 0.005 mol of tetra(triphenylphosphine)palladium, 120 mL of water, and 1000 mL of dioxane were added to a reaction flask. The mixture was heated to 90 °C and reacted for 6 h. The reaction was monitored by TLC until complete. Water and dichloromethane were added for extraction. After separating the organic phase, the mixture was concentrated to obtain M1-A.

[0127] M1-A (0.4 mol), triphenylphosphine (1.2 mol), and o-dichlorobenzene (500 ml) were added to a reaction flask and heated to reflux for 4 h. The reaction was monitored by TLC until complete. After the solvent was removed by vacuum distillation, M1-B was purified by column chromatography.

[0128] M1-B (0.2 mol), pinacol ester of 2-aminophenylboronic acid (0.21 mol), potassium phosphate (0.25 mol), tris(dibenzylacetone)palladium (0.002 mol), 2-dicyclohexylphosphine-2',6'-dimethoxy-biphenyl (0.004 mol), water (100 mL), and dioxane (500 mL) were added to a reaction flask. The mixture was heated to 100 °C and reacted for 8 h. The reaction was monitored by TLC until complete. Water and dichloromethane were added for extraction. After separating the organic phase, the mixture was concentrated to obtain M1-C.

[0129] M1-C (0.15 mol), copper powder (0.15 mol), and 300 ml of dimethyl sulfoxide were added to a reaction flask. The mixture was cooled to 20 °C, and 0.3 mol of tert-butyl nitrite was added dropwise. After the addition was complete, the mixture was heated to reflux at 60 °C for 4 h. The reaction was monitored by TLC until it was complete. The solvent was removed by vacuum distillation, and the mixture was purified by column chromatography to obtain M1-D (MS, 310.1).

[0130] M1-D (0.1 mol), 2-bromo-3-chlorophenol, sodium tert-butoxide (0.3 mol), tris(dibenzylacetone)palladium (0.001 mol), 2-dicyclohexylphosphine-2',6'-dimethoxybiphenyl (0.002 mol, S-Phos), and xylene (300 mL) were added to a reaction flask and heated to 140 °C for 8 h. The reaction was monitored by TLC until complete. After cooling, water and dichloromethane were added for extraction. The organic phase was concentrated and purified by column chromatography to obtain M1-E.

[0131] M1-E (0.08 mol) was added to 200 mL of LMF (N,N-dimethylformamide), cooled to 0 °C, and 0.1 mol of sodium hydroxide was slowly added. The mixture was heated to 60 °C and reacted for 3 h. The reaction was monitored by TLC until it was complete. The reaction solution was cooled and then introduced into 500 mL of water. A large amount of solid was generated. The mixture was filtered, and the filter cake was washed with ethanol to obtain the dried intermediate M1-F.

[0132] M1-F (0.06 mol), pinacol diborate (0.08 mol), tris(dibenzylacetone)palladium (0.0008 mol), 2-dicyclohexylphosphine-2',6'-dimethoxybiphenyl (0.0016 mol, S-Phos), potassium acetate (0.1 mol), and 200 ml of dioxane were added to a reaction flask and heated to reflux for 6 h. After the reaction was completed by TLC monitoring, the reaction solution was directly filtered and concentrated. Methanol was added to the concentrated solution and stirred, and a large amount of solid precipitated out. M1 was obtained by filtration.

[0133] Furthermore, starting from M1-D above, by replacing different raw materials, we can obtain M2 to M8.

[0134]

[0135]

[0136] Synthesis of intermediate M9:

[0137]

[0138] The synthesis of intermediate M9 can be achieved, for example, through the following operations, but is not limited to the following methods:

[0139] 0.5 mol of 1-naphthoic acid, 0.6 mol of 1,2-dichloro-4-fluoro-3-nitrobenzene, 0.6 mol of potassium carbonate, 0.005 mol of tetra(triphenylphosphine)palladium, 120 mL of water, and 1000 mL of dioxane were added to a reaction flask. The mixture was heated to 90 °C and reacted for 6 h. The reaction was monitored by TLC until complete. Water and dichloromethane were added for extraction. After separating the organic phase, the mixture was concentrated to obtain M9-A.

[0140] M9-A (0.35 mol), triphenylphosphine (1.75 mol), and o-dichlorobenzene (500 ml) were added to a reaction flask and heated to reflux for 4 h. The reaction was monitored by TLC until complete, and the solvent was removed by vacuum distillation and purified by column chromatography to obtain M9-B.

[0141] M9-B (0.23 mol), pinacol ester of 2-aminophenylboronic acid (0.27 mol), potassium phosphate (0.3 mol), tris(dibenzylacetone)palladium (0.002 mol), 2-dicyclohexylphosphine-2',6'-dimethoxy-biphenyl (0.004 mol), water (100 mL), and dioxane (500 mL) were added to a reaction flask and heated to 100 °C for 8 h. The reaction was monitored by TLC until complete. Water and dichloromethane were added for extraction, and the organic phase was separated and concentrated to obtain M9-C.

[0142] M9-C (0.18 mol), copper powder (0.18 mol), and 300 mL of dimethyl sulfoxide were added to a reaction flask. The mixture was cooled to 20 °C, and 0.3 mol of tert-butyl nitrite was added dropwise. After the addition was complete, the mixture was heated to reflux at 60 °C for 4 h. The reaction was monitored by TLC until it was complete. The solvent was removed by vacuum distillation, and the mixture was purified by column chromatography to obtain M9-D (MS, 310.1).

[0143] M9-D (0.12 mol), 2-bromo-3-chlorophenol (0.15 mol), sodium tert-butoxide (0.2 mol), tris(dibenzylacetone)palladium (0.001 mol), 2-dicyclohexylphosphine-2',6'-dimethoxybiphenyl (0.002 mol, S-Phos), and xylene (300 mL) were added to a reaction flask and heated to 140 °C for 8 h. The reaction was monitored by TLC until complete. After cooling, water and dichloromethane were added for extraction. The organic phase was concentrated and purified by column chromatography to obtain M9-E.

[0144] M9-E (0.08 mol) was added to 200 mL of LMF (N,N-dimethylformamide), cooled to 0 °C, and 0.1 mol of sodium hydroxide was slowly added. The mixture was heated to 60 °C and reacted for 3 h. The reaction was monitored by TLC until it was complete. The reaction solution was cooled and then introduced into 500 mL of water. A large amount of solid was generated. The mixture was filtered, and the filter cake was washed with ethanol to obtain the dried intermediate M9-F.

[0145] M9-F (0.05 mol), pinacol diborate (0.07 mol), tris(dibenzylacetone)palladium (0.0005 mol), 2-dicyclohexylphosphine-2',6'-dimethoxybiphenyl (0.001 mol, S-Phos), potassium acetate (0.1 mol), and 200 ml of dioxane were added to a reaction flask and heated to reflux for 6 h. After the reaction was completed by TLC monitoring, the reaction solution was directly filtered and concentrated. Methanol was added to the concentrated solution and stirred, and a large amount of solid precipitated out. M9 was obtained by filtration.

[0146] M9-D is used to obtain M9-M16 in the table below using a method similar to that used for intermediates M1-M8.

[0147]

[0148]

[0149]

[0150] Synthesis Examples

[0151] Synthesis Example 1: Synthesis of Compound P1

[0152]

[0153] M9 (0.05 mol), S1 (0.06 mol), potassium carbonate (0.08 mol), tetra(triphenylphosphine)palladium (0.0005 mol), water (20 mL), and dioxane (150 mL) were added to a reaction flask. The mixture was heated to 100 °C and reacted for 5 h. The reaction was monitored by TLC until complete. Water and dichloromethane were added for extraction. After separating the organic phase, the mixture was concentrated and purified by column chromatography to obtain P1 (MS, 642.16).

[0154] Synthesis Examples 2-15

[0155] The materials listed in the table below were fed into the reactor, and the synthesis of Examples 2-15 was carried out using the same method as in the synthesis examples.

[0156]

[0157]

[0158]

[0159]

[0160] Synthesis Example 16

[0161] Compounds C1 and C2 were synthesized based on the method reported in CN110268037A. Their structural formulas are as follows, and the specific process will not be described in detail.

[0162]

[0163] Other compounds of this invention can be obtained from intermediates M1-M16 via a simple Suzuki coupling reaction, and will not be listed individually. Compounds for which no specific synthesis method is given in the synthesis examples were also prepared using similar methods, requiring only the replacement of the starting materials; these will not be elaborated here, or those skilled in the art can prepare them using other methods in the prior art. In this invention, mass spectrometry (MS) analysis of intermediates and final products was performed using an ABSCIEX mass spectrometer (4000QTRAP). The above synthesis methods are merely illustrative and not intended to be limiting.

[0164] Device Examples

[0165] Example 1

[0166] The above embodiments and comparative examples each provide an organic electroluminescent device, and the specific fabrication methods are as follows:

[0167] 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.

[0168] The glass substrate with the ITO anode was placed in a vacuum chamber and evacuated to a vacuum level of <1×10⁻⁶. -5 Pa, on the above-mentioned anode film, a 10 nm HT-4:HI-3 (97 / 3, w / w) mixture is vacuum thermally deposited as a hole injection layer; a 60 nm HT-4 compound is used as a hole transport layer; on the hole transport layer, a HT-47 compound is vacuum-deposited as an electron blocking layer material for the device, with a deposition rate of 0.1 nm / s and a total film thickness of 60 nm; a 40 nm P1:RPD-8 (100:3, w / w) binary mixture is used as a light-emitting layer; on the light-emitting layer, a 5 nm ET-17 compound is vacuum-deposited as a hole blocking layer for the device; a 25 nm ET-69:ET-57 (50 / 50, w / w) mixture is used as an electron transport layer; a 1 nm LiF compound is used as an electron injection layer; and a 150 nm aluminum compound is used as a cathode.

[0169] In the above steps, the total evaporation rate of all organic layers and LiF was controlled at 0.1 nm / s, and the evaporation rate of the metal electrode was controlled at 1 nm / s.

[0170] Examples 2-16, Comparative Examples 1 and 2

[0171] Under the same conditions, the compound P1 in the above-mentioned device was replaced with the compounds in the table below, and the same implementation was carried out as in the device examples. Device Examples 2-16, Comparative Examples 1 and 2, wherein the structure of the main material used in the comparative examples is as follows:

[0172]

[0173] Performance testing

[0174] The following performance tests were performed on the organic electroluminescent devices provided in the above embodiments and comparative examples:

[0175] Under the same brightness, the driving voltage and current efficiency of the organic electroluminescent device were measured. Specifically, the voltage was increased at a rate of 0.1V per second, and the efficiency was measured when the brightness of the organic electroluminescent device reached 3000 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.

[0176] The measurement data (voltage and efficiency) of Comparative Example 1 are set as reference data, and all other data are normalized values, as detailed in Table 1.

[0177] Table 1

[0178]

[0179]

[0180] Compared to compounds C1 and C2, compounds of this invention offer better device efficiency. A possible difference lies in the fact that this invention involves the formation of a 6-membered heterocycle with carbazole via O or S atoms. This results in a shallower HOMO energy level, facilitating hole injection. The 6-membered heterocycle also provides a larger planar structure, enhancing both injection ease and transport capabilities. Furthermore, the specific aromatic substituents containing heteroatoms match the parent nucleus energy level, further improving device efficiency. The resulting device performance is shown in Table 1 above, exhibiting higher current efficiency and lower voltage.

[0181] The present invention has been illustrated with the above embodiments to explain the detailed method of the present invention. However, the present invention is not limited to the above detailed method, that is, it does not mean that the present invention must rely on the above detailed method to be implemented. Although the present invention has been described in conjunction with the embodiments, the present invention is not limited to the above embodiments. It should be understood that, guided by the concept of the present invention, those skilled in the art can make various modifications and improvements. The appended claims summarize the scope of the present invention. Equivalent substitutions of various raw materials in the product of the present invention, the addition of auxiliary components, and the selection of specific methods all fall within the protection scope and disclosure scope of the present invention.

Claims

1. An organic compound, characterized in that, It has the structure shown in equation (2) or (3): Equation (2) Equation (3), In equation (2), X 12 X 17 For C atoms, X 13 ~X 16 One of them is CR 2 The rest are CH, X 11 For CR 1 ; In equation (3), X 11 X 13 For C atoms, X 14 ~X 17 One of them is CR 2 The rest are CH, X 12 For CR 1 ; Y 1 For O or S, Y 2 For O or S; X 1 ~X 10 For CR 1 Or N; R 1 It is independently selected from one of hydrogen, halogen, cyano, nitro, hydroxyl, amino, substituted or unsubstituted C1-C20 alkyl, substituted or unsubstituted C1-C20 alkoxy, substituted or unsubstituted C1-C20 silyl, substituted or unsubstituted C6-C60 arylamino, substituted or unsubstituted C3-C60 heteroarylamino, substituted or unsubstituted C6-C60 aryl, and substituted or unsubstituted C3-C60 heteroaryl; The R 2 The group is selected from the following structures. ； The substitution or non-substitution in the above-mentioned groups refers to being replaced by one or a combination of at least two of the following: halogen, C1-C20 alkyl, C1-C20 alkoxy, C1-C20 silyl, cyano, nitro, hydroxyl, amino, C6-C30 arylamino, C3-C30 heteroarylamino, C6-C30 aryloxy, C3-C30 heteroaryloxy, C6-C60 aryl, and C3-C60 heteroaryl.

2. The organic compound according to claim 1, characterized in that, R 1 It is independently selected from one of hydrogen, halogen, cyano, nitro, hydroxyl, amino, C1-C20 alkyl, C1-C20 alkoxy, C6-C30 aryl, and C3-C30 heteroaryl.

3. The organic compound according to claim 1 or 2, characterized in that, R 1 It is independently selected from one of hydrogen, C1-C20 alkyl, and C1-C20 alkoxy.

4. Compounds having the following structures: 。 5. An application of a compound according to any one of claims 1-4, characterized in that, The compound is used in organic electronic devices.

6. The application according to claim 5, characterized in that, The organic electronic devices include organic electroluminescent devices, optical sensors, solar cells, lighting elements, organic thin-film transistors, organic field-effect transistors, organic thin-film solar cells, information tags, electronic artificial skin sheets, sheet-type scanners, or electronic paper.

7. The application according to claim 5, characterized in that, The compound is used in red organic light-emitting devices.

8. The application according to claim 5, characterized in that, The compound is used as the host material for the organic electroluminescent device.

9. An organic electroluminescent device, characterized in that, The organic electroluminescent device includes a first electrode, a second electrode, and an organic layer inserted between the first electrode and the second electrode, wherein the organic layer contains at least one compound according to any one of claims 1-4.

10. The organic electroluminescent device according to claim 9, characterized in that, The organic layer includes a light-emitting layer, which contains at least one compound according to any one of claims 1-4.

11. The organic electroluminescent device according to claim 9, characterized in that, The light-emitting layer comprises a host material and a dopant material, wherein the host material comprises at least one compound according to any one of claims 1-4.

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