A meta-n-heterocycle substituted diene compound and use thereof

Abstract

This invention discloses a compound with a diene as the parent skeleton and nitrogen-containing heterocycles linked at meta positions, having the structure of Formula I. By introducing meta-N heterocyclic groups into the diene core, this invention achieves precise control over the molecular frontier orbitals and dipole moments, resulting in excellent p-type doping performance. Formula I

Description

Technical Field

[0001] This invention relates to the field of organic optoelectronic materials technology, specifically to a compound with a diene as the parent skeleton and nitrogen-containing heterocycles linked at meta sites, and the application of this compound as a p-type dopant in organic electroluminescent devices. Background Technology

[0002] Organic light-emitting diodes (OLEDs), as a new generation of display and lighting technology, have outstanding advantages such as self-illumination, wide viewing angle, high contrast, fast response and flexibility, and have been widely commercialized in fields such as smartphones, televisions, automotive displays and solid-state lighting.

[0003] A typical OLED device has a multilayer stacked structure, consisting of, from bottom to top, an anode, a hole injection layer (HIL), a hole transport layer (HTL), an emissive layer (EML), an electron transport layer (ETL), an electron injection layer (EIL), and a cathode. When a voltage is applied, holes are injected from the anode and transported to the EML via the HTL; electrons are injected from the cathode and transported to the EML via the ETL. Holes and electrons recombine in the EML to form excitons, which emit light through exciton radiative decay. To improve the hole injection and transport efficiency and reduce the driving voltage, p-type dopants are typically introduced into the HTL side. P-type dopants generate free holes by accepting electrons from the HTL host material, thereby increasing the hole concentration, lowering the hole injection barrier, and improving the device's operating voltage and power efficiency. An ideal p-type dopant should possess: (1) a suitable LUMO level (approximately -5.0 to -5.75 eV) to achieve efficient electron transfer with the HOMO level (approximately -5.1 to -5.6 eV) of commonly used HTL host materials; (2) good thermal stability and film-forming properties to adapt to vacuum evaporation processes; and (3) low operating voltage, high efficiency, and long operating lifetime in devices.

[0004] Existing technologies have disclosed compounds with a diene-based core skeleton and nitrogen-containing heterocyclic substitution as p-type dopants. In these disclosed solutions, the nitrogen-containing heterocyclic group is connected to the diene core benzene ring via the para-position (i.e., 1,4-position), forming a linear para-conjugated topology between the N-heterocyclic ring and the diene core. These para-connected compounds exhibit certain p-type doping performance in devices, but their LUMO level tuning range is limited. Furthermore, the strong molecular planarity and small dipole moment caused by para-conjugation are detrimental to the optimization of interfacial charge transfer. Summary of the Invention

[0005] The purpose of this invention is to overcome the aforementioned shortcomings of the prior art and provide a diene compound containing meta-N heterocyclic substitution and its application in organic electronic devices. The compounds of this invention achieve fine-tuning of the molecular frontier orbitals and dipole moments by introducing meta-N heterocyclic groups into the diene core, resulting in excellent p-type doping performance.

[0006] A first aspect of the present invention provides a compound having the structure shown in Formula I: Formula I; Wherein, L1 has the structure shown in Equation II: Formula II; L2 has the structure shown in Equation III: Formula III; Formula III Among them, the asterisk " "Indicates the position of combination, R1 and R2 are each independently selected from electron-withdrawing groups, wherein the electron-withdrawing groups are selected from halogens, nitrosyl, nitro, acyl, carbonyl, carboxylic acid, ester, -CN, -NC, -SCN, -OCN, -SF5, borane, sulfinyl, sulfonyl, phosphoxy, nitrogen-containing heteroaryl, or C1-C20 alkyl, C1-C20 heteroalkyl, C3-C20 cycloalkyl, C2-C20 heterocycloalkyl, C1-C20 alkoxy, C1-C20 alkylthio, C1-C20 alkylsilyl, C2- C20 alkenyl, C2-C20 alkynyl, C6-C30 aryl, C3-C30 heteroaryl, C6-C30 aryloxy, C3-C30 heteroaryloxy, C6-C30 arylthio, C3-C30 heteroarylthio, C7-C30 arylalkyl, C6-C30 arylsilyl, wherein R' is selected from the group consisting of: deuterium (D), halogen, nitrosyl, nitro, acyl, carbonyl, carboxylic acid, ester, -CN, -NC, -SCN, -OCN, -SF5, boroalkyl, sulfinyl, sulfonyl, phosphoxy, mercapto; R3 and R4 are each independently selected from H, deuterium (D), halogen, -CN, -CF3, partially fluorinated or perfluorinated C1-C4 alkyl, -SF5; R5 is independently selected from H, D, halogen, -CN, -CF3, partially fluorinated or perfluorinated C1-C8 alkyl, substituted or unsubstituted C6-C30 aryl, substituted or unsubstituted C2-C30 heteroaryl, -SF5, wherein one or more substituents on the C6-C30 aryl and C2-C30 heteroaryl are independently selected from D, halogen, -CN, partially fluorinated C1-C8 alkyl, perfluorinated C1-C8 alkyl, -SF5.

[0007] Xn1 is selected from N or CRn4; Rn1, Rn2, Rn3, and Rn4 are each independently selected from H, deuterium (D), halogen, nitroso, nitro, acyl, carbonyl, carboxylic acid, ester, -CN, isocyanate, -SCN, -OCN, -SF5, borane, sulfinyl, sulfonyl, phosphoxy, mercapto, C1-C20 alkyl, C1-C20 heteroalkyl, C3-C20 cycloalkyl, C2-C20 heterocycloalkyl, C1-C20 alkoxy, C1-C20 alkylthio, C1-C20 alkylsilyl, C2-C20 alkenyl, C2-C2 C6-C30 aryl, C3-C30 heteroaryl, C6-C30 aryloxy, C3-C30 heteroaryloxy, C6-C30 arylthio, C3-C30 heteroarylthio, C7-C30 arylalkyl, C6-C30 arylsilyl, wherein C1-C20 alkyl, C1-C20 heteroalkyl, C3-C20 cycloalkyl, C2-C20 heterocycloalkyl, C1-C20 alkoxy, C1-C20 alkylthio, C1-C20 alkylsilyl, C2-C20 alkenyl, C2-C20 alkynyl, C6- C30 aryl, C3-C30 heteroaryl, C6-C30 aryloxy, C3-C30 heteroaryloxy, C6-C30 arylthio, C3-C30 heteroarylthio, C7-C30 arylalkyl, and C6-C30 arylsilyl may optionally be substituted with the following substituents: deuterium (D), halogen, nitroso, nitro, acyl, carbonyl, carboxylic acid, ester, -CN, -NC, -SCN, -OCN, -SF5, boranealkyl, sulfinyl, sulfonyl, phosphoxy, mercapto, C1-C20 alkyl, and C1-C20 heteroalkyl. C3-C20 cycloalkyl, C2-C20 heterocycloalkyl, C1-C20 alkoxy, C1-C20 alkylthio, C1-C20 alkylsilyl, C2-C20 alkenyl, C2-C20 alkynyl, C6-C30 aryl, C3-C30 heteroaryl, C6-C30 aryloxy, C3-C30 heteroaryloxy, C6-C30 arylthio, C3-C30 heteroarylthio, C7-C30 arylalkyl, C6-C30 arylsilyl; wherein adjacent Rn2 and Rn4 are not connected or are linked by chemical bonds to form a ring; According to the compound of the first aspect, the compound satisfies one or more of the following conditions: (1a) Compound I of formula contains at least two and no more than eight -CN groups; (2a) The electron-withdrawing group is selected from the group consisting of: halogen, C1-C8 haloalkyl, C1-C8 haloalkoxy, -SF5, sulfonyl, -CN, -NC, -SCN, -OCN, C3-C12 nitrogen-containing heteroaryl; (3a) The electron-withdrawing group is selected from the group consisting of: F, -CF3, -OCF3, -SF5, -SO2CF3, -NC, -SCN, -SCN, -OCN, pyrimidinyl, triazineyl.

[0008] According to the compound of the first aspect, the compound satisfies one or more of the following conditions: (1b) R1 and R2 are each independently selected from -CN, -CF3, partially fluorinated or perfluorinated C1-C8 alkyl, -SF5, halogen, C6-C30 aryl, C2-C30 heteroaryl; the C6-C30 aryl and C2-C30 heteroaryl are optionally substituted with substituents selected from the following: deuterium (D), partially fluorinated or perfluorinated C1-C8 alkyl, -CF3, halogen, -SF5, -CN; (2b) R1 and R2 are each independently selected from -CN, partially fluorinated C1-C4 alkyl or perfluorinated C1-C4 alkyl, -CF3, C6-C24 aryl, C3-C24 heteroaryl; the C6-C24 aryl and C3-C24 heteroaryl are optionally substituted with substituents selected from the following: deuterium (D), partially fluorinated C1-C4 alkyl or perfluorinated C1-C4 alkyl, -CF3, halogen, F, -CN; (3b) At least one of R1 and R2 is selected from -CN or -CF3; (4b) Both R1 and R2 are -CN.

[0009] According to the compound of the first aspect, the compound satisfies one or more of the following conditions: (1c) R3 and R4 are each independently selected from H, deuterium (D), -CN, partially fluorinated C1-C4 alkyl, perfluorinated C1-C4 alkyl or -CF3; (2c) R3 and R4 are each independently selected from H, deuterium (D), -CN, and -CF3; (3c) R3 and R4 are each independently selected from H and deuterium (D); (4c) R5 is selected from H, deuterium (D), halogen, -CN, partially fluorinated C1-C4 alkyl, perfluorinated C1-C4 alkyl, -CF3C6-C24 aryl, C3-C24 heteroaryl; said C6-C24 aryl, C3-C24 heteroaryl are optionally substituted with substituents selected from the following: deuterium (D), halogen, CN, partially fluorinated C1-C4 alkyl, perfluorinated C1-C4 alkyl, -CF3; (5c) R5 is selected from H, deuterium (D), F, -CN, partially fluorinated C1-C4 alkyl, perfluorinated C1-C4 alkyl, -CF3C6-C18 aryl, C3-C18 heteroaryl; said C6-C18 aryl, C3-C18 heteroaryl are optionally substituted with substituents selected from the following: deuterium (D), halogen, CN, partially fluorinated C1-C4 alkyl, perfluorinated C1-C4 alkyl, -CF3; (6c) R5 is selected from H, deuterium (D), -CN, -CF3, C6 aryl, C4-C5 heteroaryl, wherein the C6 aryl and C4-C5 heteroaryl are optionally substituted by substituents selected from the following: deuterium (D), halogen, CN, partially fluorinated C1-C4 alkyl, perfluorinated C1-C4 alkyl, -CF3.

[0010] According to the compound of the first aspect, the compound satisfies one or more of the following conditions: (1d) At least one of Rn1, Rn2, Rn3, and Rn4 has one or more electron-withdrawing groups; (2d) The group is selected from any one of the following groups: pyridyl, pyrimidinyl, triazinyl, pyrazinyl, pyridazinyl, quinolinyl, isoquinolinyl, quinoxalinyl, quinazolinyl, benzimidazolyl, phenanthrolineyl, wherein the pyridyl, pyrimidinyl, triazinyl, pyrazinyl, pyridazinyl, quinolinyl, isoquinolinyl, quinoxalinyl, quinazolinyl, benzimidazolyl, phenanthrolineyl is optionally substituted by a substituent selected from the following: -CN, -CF3, -F; (3d)Rn4 is a group having at least one or more electron-withdrawing groups; (4d)Xn1 is CRn4.

[0011] In this invention, the "group having one or more electron-withdrawing groups" contains 1, 2, 3, 4, 5, 6, 7, 8, 9, 10 or more electron-withdrawing groups.

[0012] In one embodiment of the present invention, the electron-withdrawing group is selected from any one or a combination of at least two of the following groups: halogen, nitrosyl, nitro (-NO2), acyl, carbonyl, carboxylic acid, ester, -CN, -NC, -SCN, -OCN, -SF5, borane, sulfinyl, sulfonyl, phosphoxy, nitrogen-containing heteroaryl (e.g., C3-C20, preferably C3-C12 nitrogen-containing heteroaryl), or is selected from halogen, nitrosyl, -NO2, acyl, carbonyl, carboxylic acid, ester, -CN, -NC, -SCN, -OCN, -SF5, borane, sulfinyl, sulfonyl, phosphoxy, nitrogen-containing heteroaryl. The following groups are replaced by one or more substituents in (e.g., C3-C20, preferably C3-C12 nitrogen-containing heteroaryl): C1-C20 alkyl, C1-C20 heteroalkyl, C3-C20 cycloalkyl, C2-C20 heterocycloalkyl, C1-C20 alkoxy, C1-C20 alkylthio, C1-C20 alkylsilyl, C2-C20 alkenyl, C2-C20 alkynyl, C6-C30 aryl, C3-C30 heteroaryl, C6-C30 aryloxy, C3-C30 heteroaryloxy, C6-C30 arylthio, C3-C30 heteroarylthio, C7-C30 arylalkyl, C6-C30 arylsilyl.

[0013] The “C3-C20 nitrogen-containing heteroaryl” mentioned in the electron-withdrawing group of the present invention can be, for example, nitrogen-containing heteroaryl groups of C3, C4, C5, C6, C9, C10, C12, C14, C15, C16, C18, and C20.

[0014] According to molecular orbital theory, in meta-substituted benzene rings, there is no direct resonance path between the two substituents, and orbital overlap is blocked. A paper from Angew. Chem. 2025 has clearly confirmed that the HOMO-LUMO gap (8.01 eV) of meta-substituted benzene rings is significantly larger than that of para-substituted benzene rings (6.28 eV), with a difference of 1.73 eV. This means that meta-remodeling severs the para-conjugated channel between the N-heterocycle and the dicyano group through the central benzene ring, leading to a systematic change in the frontier orbital energy levels.

[0015] Based on the aforementioned scientific principles, the inventors of this invention creatively conceived of shifting the N-heterocycle from the para position to the meta position of the diene core, utilizing the blocking effect of meta-linking on conjugation to modulate the LUMO energy level. More importantly, and unexpectedly, it was discovered that although meta-linking partially disrupts conjugation and increases the HOMO-LUMO gap, the resulting refined modulation of the LUMO energy level, enhanced dipole moment (due to the disruption of the molecule's centrosymmetry by meta-linking), and improved interfacial charge transfer efficiency actually enable the meta-linked compound to exhibit significantly superior overall performance compared to the para isomer in OLED devices.

[0016] Based on the compounds in the first aspect, R5 is selected from the group consisting of structures A1 to A105. Indicates the linkage site of the functional group:

[0017]

[0018] Preferably, R5 is selected from structures A1 to A80; More preferably, R5 is selected from structures A1 to A50; More preferably, R5 is selected from structures A1 to A41.

[0020] According to the compound of the first aspect, R1 and R2 are identical and selected from -CN, and the compound has the structure shown in Formula I-1: Formula I-1; Preferably, R3 and R4 are the same and are selected from H or deuterium (D); More preferably, the compound has the structure shown in Formula I-2: Formula I-2; More preferably, Xn1 is selected from formula CRn4; More preferably, Rn1, Rn2, Rn3, and Rn4 are each independently selected from H, deuterium (D), halogen, -CN, partially fluorinated C1-C8 alkyl or perfluorinated C1-C8 alkyl, -CF3, C6-C30 aryl, and C3-C30 heteroaryl, wherein the C6-C30 aryl and C3-C30 heteroaryl are optionally substituted by D, partially fluorinated C1-C8 alkyl, perfluorinated C1-C8 alkyl, -CF3, halogen, and -CN; and wherein at least one of Rn1, Rn2, Rn3, and Rn4 is selected from partially fluorinated C1-C8 alkyl or perfluorinated C1-C8 alkyl, halogen, and -CN, and adjacent Rn2 and Rn4 are not connected or are linked by chemical bonds to form a ring.

[0021] In this specification, it should be noted that throughout the application and claims, any R1, R2, R3, R4, R5, Rn1, Rn2, Rn3, and Rn4, etc., always refer to the same part, unless otherwise noted.

[0022] It should be noted that, in this invention, the possible effects of each group / feature have been described separately for ease of explanation, but this does not mean that these groups / features act in isolation. In fact, the essential reason for obtaining good performance is the optimized combination of the entire molecular structure, which is the result of the synergistic effect between various groups, rather than the effect of a single group / feature.

[0023] According to the compounds of the first aspect, the compounds are selected from the group consisting of compounds I-1 to I-57:

[0024]

[0025]

[0026]

[0027] .

[0028] The second aspect of the present invention provides the application of the compounds of the first aspect in organic electronic devices; Preferably, the organic electronic device is an organic electroluminescent device; More preferably, the organic electroluminescent device includes an organic semiconductor layer, the organic semiconductor layer including the compound of the first aspect; More preferably, the organic electronic device is an organic light-emitting diode (OLED).

[0029] A third aspect of the present invention provides an organic electroluminescent device, comprising a first electrode, a second electrode, and at least one organic layer disposed between the first electrode and the second electrode, wherein the organic layer comprises at least one compound of the first aspect; Preferably, the organic layer comprises a hole injection layer and / or a hole transport layer, wherein the hole injection layer and / or the hole transport layer comprises at least one compound of the first aspect; More preferably, the organic layer further includes at least one of a light-emitting layer, an electron blocking layer, a hole blocking layer, an electron transport layer, and an electron injection layer.

[0030] According to the organic electroluminescent device of the third aspect, the amount of the compound of the first aspect in the hole injection layer is 1% to 100% of the total weight of the hole injection layer; Preferably, when the compound of the first aspect is combined with other compounds in the hole injection layer, the amount of the compound of the first aspect in the hole injection layer is 1% to 99% of the total weight of the hole injection layer, more preferably 1% to 10%.

[0031] In some embodiments, the amount of the compound of the first aspect in the hole injection layer is 1% to 100% of the total weight of the hole injection layer (e.g., it can be 1%, 2%, 3%, 4%, 5%, 6%, 7%, 8%, 9%, 10%, 15%, 25%, 30%, 35%, 40%, 45%, 50%, 55%, 60%, 65%, 70%, 75%, 80%, 85%, 90%, 95%, 99%, 100% or any value between them).

[0032] According to the organic electroluminescent device of the third aspect, the hole injection layer and / or hole transport layer further comprises at least one hole transport material; Preferably, the hole transport material comprises at least one of the following: triarylamine compound, spirodifluorene compound, pentanebenzene compound, oligothiophene compound, oligophenyl compound, oligophenylene vinylidene compound, oligofluorene compound, porphyrin complex, and metal phthalocyanine complex; More preferably, the molar doping ratio of the compound of the first aspect to the hole transport material is 10000:1 to 1:10000, and even more preferably 10:1 to 1:100.

[0033] As a preferred embodiment of the present invention, the molar doping ratio of the compound of the first aspect to the hole transport material is 10:1 to 1:100 (for example, it can be 9:1, 8:1, 7:1, 6:1, 5:1, 4:1, 3:1, 2:1, 1:1, 1:10, 1:20, 1:30, 1:40, 1:50, 1:60, 1:70, 1:80, 1:90 or any value between them).

[0034] According to a third aspect of an organic electroluminescent device, the organic electroluminescent device includes an anode, a cathode, and a plurality of stacked layers disposed between the anode and the cathode, the stacked layers including a first stacked layer and a second stacked 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-generating layer is disposed between the first stacked layer and the second stacked layer, the charge-generating layer including a p-type charge-generating layer and an n-type charge-generating layer; wherein the p-type charge-generating layer includes an organic compound of the first aspect; Preferably, the p-type charge generation layer further comprises at least one hole transport material; Preferably, the hole transport material comprises a triarylamine compound, a spirodifluorene compound, a pentanebenzene compound, an oligothiophene compound, an oligophenyl compound, an oligophenylene vinylidene compound, an oligofluorene compound, a porphyrin complex, or a metal phthalocyanine complex; Preferably, the molar doping ratio of the compound of the first aspect to the hole transport material is 10000:1 to 1:10000, more preferably 10:1 to 1:100; Preferably, the charge generation layer further includes a buffer layer disposed between the p-type charge generation layer and the n-type charge generation layer, the buffer layer comprising the compound of the first aspect.

[0035] As a preferred embodiment of the present invention, the molar doping ratio of the compound of the first aspect to the hole transport material is 10:1 to 1:100 (for example, it can be 9:1, 8:1, 7:1, 6:1, 5:1, 4:1, 3:1, 2:1, 1:1, 1:10, 1:20, 1:30, 1:40, 1:50, 1:60, 1:70, 1:80, 1:90 or any value between them).

[0036] A fourth aspect of the present invention provides a display assembly including the organic electroluminescent device of the third aspect; Preferably, the display component is selected from at least one of the following: flat panel display, monitor, medical monitor, television set, billboard, lamp for indoor or outdoor lighting and / or signaling, head-up display, fully or partially transparent display, flexible display, smartphone, tablet computer, tablet phone, wearable device, smartwatch, laptop computer, digital camera, portable camcorder, viewfinder, microdisplay, 3D display, vehicle display, and taillight.

[0037] The organic compounds provided by this invention can be used as charge transport materials, charge injection materials and similar materials in organic electroluminescent devices.

[0038] Compared with the prior art, the present invention has the following beneficial effects: The compounds of formula I of this invention solve the fundamental problems of the invention by making the devices superior in all respects to organic electroluminescent devices known in the art, particularly in terms of operating voltage, efficiency, and / or lifetime, and especially in terms of operating voltage, efficiency, and voltage stability over time. It has also been surprisingly found that, compared to comparative examples, the compounds of formula (I) can have improved LUMO energy levels, improved dipole moments, and / or improved thermal properties, particularly improved thermal stability and / or processability at elevated temperatures.

[0039] The compound of formula (I) exhibits good thermal properties, such as evaporation temperature, which is beneficial for the fabrication of OLED devices. When used as a p-type dopant in OLED devices, it exhibits good performance characteristics, such as low operating voltage, low operating voltage over time, high efficiency, and long lifetime. Furthermore, the compound of formula I exhibits low mass loss during heating, thus avoiding tool contamination during the fabrication of organic electronic devices.

[0040] Specifically, the present invention has the following advantages over the prior art: (1) Selective cleavage of conjugated channels and enhanced stability. The meta-linking mode cleaves the para-conjugated channel between the nitrogen-containing heterocyclic group and the R1 / R2 electron-withdrawing group through the central benzene ring. According to molecular orbital theory, there is no direct resonance path between the two substituents on the meta-substituted benzene ring, and orbital overlap is blocked. The HOMO-LUMO gap of the meta-substituted benzene ring (8.01 eV) is significantly larger than that of the para-substituted benzene ring (6.28 eV), with a difference of 1.73 eV. This "cleavage" effect reduces the HOMO-LUMO orbital overlap caused by excessive molecular conjugation, reduces excited-state structural relaxation, and thus improves the thermal and electrochemical stability of the compound. In the prior art, para-linking forms a continuous conjugated path between the nitrogen-containing heterocyclic group and the electron-withdrawing group. Although this is beneficial for LUMO downshifting, it also leads to the inherent contradiction of excessive HOMO-LUMO overlap and decreased molecular stability. The meta-linking of this invention alleviates this contradiction at its source.

[0041] (2) Compensation effect of local electronic structure modulation. Although meta-linking cuts off the long-range conjugated channel between the nitrogen-containing heterocycle and the diene core, the inventors have discovered that by introducing electron-withdrawing groups (such as cyano groups) onto the nitrogen-containing heterocycle, the local electron affinity of the nitrogen-containing heterocycle can be modulated using inductive and local conjugation effects, thus bringing the overall LUMO back to the target range required for p-type doping without restoring long-range conjugation. This "cut-off-compensation" design strategy achieves a new balance between LUMO energy levels and molecular stability. The conventional approach is to "restore" the conjugated path after the conjugation is cut off (such as by introducing bridging groups), while this invention takes the opposite approach, utilizing the new electronic structure characteristics after the conjugation is cut off to achieve a better performance balance through local modification. This design idea has not been disclosed in the prior art.

[0042] (3) Independent acceptor function of the dicyanoethylene nucleus. When both R1 and R2 are cyano groups, the 1,2-dicyanoethylene structure (—C(CN)=C(CN)—) itself is a strong electron acceptor unit, and its LUMO contribution mainly comes from the π of the cyano group. The conjugation of the orbital with the ethylene double bond is independent of long-range conjugation coupling with the nitrogen-containing heterocycle. The meta-linkage decouples the electronic functions of the dicyanoethylene core and the nitrogen-containing heterocycle, allowing them to function independently and avoiding the problems of excessively deep LUMO or too small HOMO-LUMO gap caused by excessive conjugation.

[0043] (4) Low symmetry inhibits molecular aggregation. Meta-linkage disrupts the centrosymmetry of molecules, reduces the tendency of molecules to crystallize and the crystal stacking energy, which is conducive to the formation of uniform amorphous films. Compared with para-linkage molecules with high symmetry, the compounds of the present invention are more likely to form dense and smooth amorphous films during vacuum thermal evaporation deposition, thereby improving the morphological stability of doped films and the operating life of devices.

[0044] (5) Enhanced doping efficiency through dipole moment modulation. Meta-connection alters the overall dipole moment direction and magnitude of the molecule, creating a favorable local electric field distribution in the doped film. This facilitates charge transfer during p-type doping, improves doping efficiency, and reduces device driving voltage.

[0045] (6) Fine-tuning of the LUMO level. DFT calculation results (GAUSS-09, B3LYP / 6-311G(d)) show that the compound of formula (I) of this invention has a LUMO level suitable for p-type doping, which is within the range required for effective hole injection and / or hole generation. Although the meta-linking partially breaks the conjugation, the LUMO level is finely tuned through the synergistic effect of the local inductive effect of the electron-withdrawing group on the nitrogen-containing heterocycle and the independent acceptor function of the dicyandiethylene core, so that it is neither too deep (leading to an excessively small HOMO-LUMO gap and decreased stability) nor too shallow (leading to insufficient doping efficiency).

[0046] (7) Significant improvement in device performance. Data from the device examples show that OLED devices using the compound of formula (I) of the present invention as p-type dopant have an 8% to 12% lower operating voltage, a 22% to 38% higher current efficiency, and a 71% to 95% higher lifetime (LT97) compared to devices using the para-isomer of the comparative compound D1. In particular, device examples 1, 2, and 5 exhibit the best overall performance, with relative current efficiencies all above 1.33 and relative lifetimes all above 1.88, representing the preferred solutions of the compound of formula (I) of the present invention.

[0047] (8) Structural universality. Compounds of formula (I) with different combinations of substituents all showed consistent superior performance compared to the para isomer D1, indicating that the performance improvement brought about by meta-linking has structural universality and does not depend on the selection of specific substituents, thus further demonstrating the creative contribution of the meta-linking topology itself.

[0048] (9) Structural novelty. The meta-linked topology makes the chemical structure of the compound of the present invention fundamentally different from that of p-type dopants using para-linking in the prior art. The linkage mode of connecting the benzene ring to a diene group at the 1-position and to a nitrogen-containing heterocycle at the 3-position has not been reported in the field of p-type dopants, opening up a new structural space for the design of p-type doped materials. Detailed Implementation

[0049] To make the objectives, technical solutions and advantages of the present invention clearer, the present invention is further described in detail below with reference to the examples. The specific examples described herein are only used to explain the present invention and are not intended to constitute any limitation on the present invention.

[0050] The dedicated word "exemplary" as used herein means "serving as an example, an embodiment or an illustration". Any embodiment described herein as "exemplary" should not be construed as being superior to or better than other embodiments.

[0051] In addition, the technical features involved in different embodiments of the present application described below can be combined with each other as long as they do not conflict with each other. In the present invention, the reference to a chemical element, unless otherwise specified, includes the concept of isotopes with the same chemical properties. For example, hydrogen (H) includes 1 H (protium), 2 H (deuterium, D), 3 H (tritium, T) and the like; carbon (C) includes 12 C, 13 C and the like.

[0052] In the present invention, halo, halogen, halogen atom, and halo group are used interchangeably and refer to fluorine, chlorine, bromine or iodine.

[0053] In the present invention, an acyl group refers to a substituted carbonyl group (COR x ).

[0054] In the present invention, an ester or ester group refers to a substituted oxycarbonyl group (-OCOR x or CO2R x ).

[0055] In the present invention, an ether or ether group refers to a -OR x group.

[0056] As used herein, thio group or thioether are used interchangeably and refer to a -SR x group.

[0057] In the present invention, a sulfinyl group refers to a -SOR x group.

[0058] In the present invention, a sulfonyl group refers to a -SO2R x group.

[0059] In the present invention, a phosphino group refers to a -PR x 3 group, wherein each R x may be the same or different.

[0060] Each of the above R xPreferably, it is selected from the group consisting of alkyl, cycloalkyl, aryl, and heteroaryl groups.

[0061] In this invention, the alkyl group includes straight-chain and branched alkyl groups. The alkyl group can be an alkyl group having 1 to 20 carbon atoms, more preferably an alkyl group having 1 to 12 carbon atoms. Examples of alkyl groups include methyl, ethyl, propyl, isopropyl, n-butyl, sec-butyl, isobutyl, tert-butyl, n-pentyl, n-hexyl, n-heptyl, n-octyl, n-nonyl, n-decyl, n-undecyl, n-dodecyl, n-tridecyl, n-tetradecyl, n-pentadecanyl, n-hexadecyl, n-heptadecyl, n-octadecyl, neopentyl, 1-methylpentyl, 2-methylpentyl, 1-pentylhexyl, 1-butylpentyl, 1-heptyloctyl, and 3-methylpentyl. Among the above, methyl, ethyl, propyl, isopropyl, n-butyl, sec-butyl, isobutyl, tert-butyl, n-pentyl, neopentyl, and n-hexyl are preferred. Furthermore, the alkyl group can optionally be substituted.

[0062] In this invention, the alkoxy group is represented by -O-alkyl. Examples and preferred examples of alkyl groups are the same as described above. The alkoxy group can be an alkoxy group having 1 to 20 carbon atoms, preferably an alkoxy group having 1 to 16 carbon atoms. Examples of alkoxy groups include methoxy, ethoxy, propoxy, butoxy, pentoxy, hexoxy, cyclopropyloxy, cyclobutyloxy, cyclopentoxy, cyclohexyloxy, tetrahydrofuranyloxy, tetrahydropyranyloxy, methoxypropyloxy, ethoxyethyloxy, methoxymethyloxy, and ethoxymethyloxy. Furthermore, the alkoxy group may optionally be substituted.

[0063] In this invention, cycloalkyl refers to a cyclic alkyl group. The cycloalkyl group can be a cycloalkyl group having 3 to 20 carbon atoms, preferably a cycloalkyl group having 4 to 16 carbon atoms. Examples of cycloalkyl groups include cyclobutyl, cyclopentyl, cyclohexyl, 4-methylcyclohexyl, 4,4-dimethylcyclohexyl, 1-adamantyl, 2-adamantyl, 1-norbornyl, 2-norbornyl, etc. Among the above, cyclopentyl, cyclohexyl, 4-methylcyclohexyl, and 4,4-dimethylcyclohexyl are preferred. Furthermore, the cycloalkyl group may optionally be substituted.

[0064] In this invention, heterocyclic alkyl refers to a group in which a single hydrogen atom or -CH2- group can be substituted with oxygen, sulfur, halogen, nitrogen, phosphorus, boron, silicon, or selenium, preferably with oxygen, sulfur, or nitrogen. Additionally, heteroalkyl or heterocyclic alkyl groups may optionally be substituted.

[0065] In this invention, aryl or aromatic ring refers to and includes monocyclic aromatic hydrocarbon groups and polycyclic aromatic ring systems. A polycyclic ring may have two or more rings in which two carbons are shared by two adjacent rings (the rings are "fused"), wherein at least one of the rings is an aromatic hydrocarbon group, and other rings may be cycloalkyl, cycloalkenyl, aryl, heterocyclic, and / or heteroaryl. Preferred aryl or aromatic rings are aryl groups containing 6 to 30 carbon atoms, preferably 6 to 20 carbon atoms, more preferably 6 to 12 carbon atoms. Particularly preferred are aryl groups having six, ten, or twelve carbon atoms. Suitable aryl groups include phenyl, biphenyl, triphenyl, triphenylene, tetraphenylene, naphthyl, anthracene, ferroyl, phenanthryl, fluorenyl, pyrene, peryl, thionyl, and azuleyl, preferably phenyl, biphenyl, triphenyl, triphenylene, fluorenyl, and naphthyl. Additionally, aryl groups may optionally be substituted.

[0066] In this invention, heteroaryl or heterocyclic aromatic ring refers to a monocyclic aromatic group and a polycyclic aromatic ring system comprising at least one heteroatom. Heteroatoms include, but are not limited to, oxygen, sulfur, nitrogen, phosphorus, boron, silicon, or selenium. In many cases, oxygen, sulfur, or nitrogen are preferred heteroatoms. A monocyclic heterocyclic aromatic system is preferably a monocyclic ring having 5 or 6 carbon atoms, and the ring may have one to six heteroatoms. A heteropolycyclic system may have two or more rings in which two atoms are shared by two adjacent rings (the rings are “fused”), wherein at least one of the rings is a heteroaryl group, and other rings may be cycloalkyl, cycloalkenyl, aryl, heterocyclic, and / or heteroaryl. A heteropolycyclic aromatic ring system may have one to six heteroatoms on each ring of the polycyclic aromatic ring system. Preferred heteroaryl groups are those containing three to thirty carbon atoms, preferably three to twenty carbon atoms, and more preferably three to twelve carbon atoms. Suitable heteroaryl groups include dibenzothiophene, dibenzofuran, dibenzoselenophene, furanyl, thiophene, benzofuran, benzothiophene, benzoselenophene, carbazolyl, indolocarbazolyl, pyridinylindolyl, pyrrolodipyridyl, pyrazolyl, imidazolyl, triazolyl, oxazolyl, thiazolyl, oxadiazolyl, oxtriazolyl, dioxazolyl, thiazolyl, pyridinyl, pyrazinyl, triazinyl, oxazinyl, oxthiazolyl, oxadiazinyl, indolyl, benzo[] Imidazolyl, indazolyl, indoxazinyl, benzoxazolyl, benzoisoxazolyl, benzothiazolyl, quinolinyl, isoquinolinyl, cenolinyl, quinazolinyl, quinoxalinyl, naphridinyl, phthalazinyl, pteridinyl, xantheneyl, acridineyl, phenazinyl, phenothiazinyl, phenoxazinyl, benzofuranopyridinyl, furanodipyridinyl, benzothiophenopyridinyl, thiophenodipyridinyl, benzoselenophenepyridinyl, selenophenedipyridinyl, 1,2-azaborylyl, 1 3-azaborylyl, 1,4-azaborylyl, boronazynyl and their aza analogs, preferably dibenzothiophenyl, dibenzofuranyl, dibenzoselenophenyl, carbazoyl, indolocarbazoyl, imidazoyl, pyridyl, triazine, benzimidazolyl, 1,2-azaborylyl, 1,3-azaborylyl, 1,4-azaborylyl, boronazynyl and their aza analogs. Additionally, the heteroaryl group may optionally be substituted.

[0067] In this invention, the C6-C60 aryloxy group is a monovalent group formed by connecting the above-mentioned aryl group with O, and the C3-C60 heteroaryloxy group is a monovalent group formed by connecting the above-mentioned heteroaryl group with O.

[0068] In this specification, unless otherwise defined, "partially fluorinated C1-C8 alkyl group" refers to a C1-C8 alkyl group in which only some of the hydrogen atoms are replaced by fluorine atoms.

[0069] In this specification, unless otherwise defined, "perfluorinated C1-C8 alkyl group" refers to a C1-C8 alkyl group in which all hydrogen atoms are replaced by fluorine atoms.

[0070] In this specification, unless otherwise defined, "substituted" means substituted with deuterium (D), halogen, F, CN, partially fluorinated C1-C4 alkyl, perfluorinated C1-C4 alkyl, or -CF3.

[0071] In this specification, "aryl group" refers to a hydrocarbon group that can be produced by formally isolating a hydrogen atom from the aromatic ring of the corresponding aromatic hydrocarbon. An aromatic hydrocarbon is a hydrocarbon containing at least one aromatic ring or aromatic ring system. Examples of aryl groups include phenyl, biphenyl, naphthyl, fluorene, etc.

[0072] In this specification, "heteroaryl" refers to a group derived by formally isolating a cyclic hydrogen atom from a heterocyclic aromatic ring in a compound containing at least one heterocyclic aromatic ring. The heteroatom is preferably selected from N, O, and S.

[0073] In this specification, "alkyl group" refers to a saturated aliphatic hydrocarbon group, which may be selected from methyl, ethyl, propyl, isopropyl, n-butyl, isobutyl, sec-butyl, tert-butyl, etc.

[0074] In this specification, "cycloalkyl" refers to a saturated aliphatic cyclic hydrocarbon group, such as cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, etc.

[0075] The term "heteroatom" is understood to mean that in a structure that can be formed by covalently bonded carbon atoms, at least one carbon atom is replaced by another multivalent atom. Preferably, the heteroatom is selected from B, Si, N, P, O, and S; more preferably, it is selected from N, O, and S.

[0076] In this specification, "fused aryl ring" refers to a fused ring system formed by two or more aromatic rings or aromatic ring systems sharing two adjacent carbon atoms, such as naphthalene, anthracene, phenanthrene, pyrene, etc.

[0077] asterisk "Indicates the position of combination.

[0078] The terms "p-type charge generation layer", "p-CGL" and "hole generation layer" are used synonymously.

[0079] The terms "OLED", "organic light-emitting diode", and "organic light-emitting device" are used synonymously.

[0080] The terms "hole injection layer" and "HIL" are used synonymously.

[0081] In this specification, hole characteristics refer to the ability to form holes by supplying electrons when an electric field is applied, and due to the conductivity characteristics based on the highest occupied molecular orbital (HOMO) energy level, holes formed in the anode can be easily injected into the light-emitting layer and transported in the light-emitting layer.

[0082] In addition, electronic properties refer to the ability to accept electrons when an electric field is applied, and due to the conductivity of the lowest unoccupied molecular orbital (LUMO) energy level, electrons formed in the cathode can be easily injected into the light-emitting layer and transported in the light-emitting layer.

[0083] As used herein, “combination of” or “group” means that one or more members of the applicable list are combined to form a known or chemically stable arrangement that can be conceived by one of ordinary skill in the art from the applicable list. For example, alkyl and deuterium can be combined to form partially or fully deuterated alkyl groups; halogen and alkyl groups can be combined to form haloalkyl substituents, such as trifluoromethyl; and halogen, alkyl and aryl groups can be combined to form haloaralkyl groups.

[0084] In this invention, the "substituted or unsubstituted" group can replace one substituent or multiple substituents. When there are multiple substituents (at least two), they can be the same or different substituents.

[0085] In the compounds mentioned in this disclosure, unless explicitly specified, for example, that adjacent substituents can optionally connect to form a ring, adjacent substituents in the compounds cannot connect to form a ring. In the compounds mentioned in this disclosure, the optional connection of adjacent substituents to form a ring includes both cases where adjacent substituents can connect to form a ring and cases where adjacent substituents do not connect to form a ring. When adjacent substituents can optionally connect to form a ring, the formed ring can be a monocyclic or polycyclic ring (including spirocyclic, bridged, fused rings, etc.), as well as an alicyclic, heterocyclic, aromatic, or heteroaromatic ring. In this context, adjacent substituents can refer to substituents bonded to the same atom, substituents bonded to carbon atoms directly bonded to each other, or substituents bonded to carbon atoms further away. Preferably, adjacent substituents refer to substituents bonded to the same carbon atom and substituents bonded to carbon atoms directly bonded to each other.

[0086] In the organic electroluminescent element of the present invention, the composition of the layers other than the layer containing the metal complex of the present invention is not limited, and those skilled in the art can determine the composition of the other layers of the organic electroluminescent element as needed based on their technical knowledge in the field.

[0087] It should be noted that the materials described in this invention for specific layers in organic light-emitting devices can be used in combination with a variety of other materials present in the device. These combinations of materials are described in detail in paragraphs 0132-0161 of U.S. Patent Application US2016 / 0359122M, the entire contents of which are incorporated herein by reference. The materials described or mentioned herein are non-limiting examples of materials that can be used in combination with the compounds disclosed herein, and those skilled in the art can readily consult the literature to identify other materials that can be used in combination.

[0088] Materials described herein for use in specific layers of organic light-emitting devices can be used in combination with a variety of other materials present in said devices. For example, the compounds disclosed herein can be used in combination with various host layers, transport layers, barrier layers, injection layers, electrodes, and other possible layers. These combinations of materials are described in detail in paragraphs 0080-0101 of U.S. Patent Application US2015 / 0349273M, the entire contents of which are incorporated herein by reference. The materials described or mentioned herein are non-limiting examples of materials that can be used in combination with the compounds disclosed herein, and those skilled in the art can readily consult the literature to identify other materials that can be used in combination.

[0089] This invention does not limit the preparation method of the compounds. Typical but non-limiting examples are the following compounds, whose synthetic routes and preparation methods are as follows: Synthesis Example 1: Synthesis of Compound I-4:

[0090] (1-1) Synthesis of intermediate S1-1: A mixture of raw materials M1-1 (75 mmol), M1-2 (100 mmol) in a 10:1 ratio of dialkyl / water, potassium phosphate (100 mmol), and 10 mol% SPhos were added to a 500 mL three-necked flask. The mixture was degassed by sonication for 15 minutes, and then 5 mol% palladium acetate (II) was added. Nitrogen was used to purge the mixture three times, and the mixture was refluxed for 24 hours.

[0091] The reaction mixture was diluted in a mixture of ethyl acetate and water. After separation, the aqueous phase was extracted with ethyl acetate, and the combined organic layers were dried over sodium sulfate, filtered through a diatomaceous earth column, and the solvent was evaporated. The crude product was purified by grinding in hexane overnight, filtering, and washing with cooled hexane. Intermediate S1-1 was given (73% yield).

[0092] (1-2) Synthesis of intermediate S1-2: Add M1-3 (50 mmol), S1-1 (50 mmol), potassium carbonate (100 mmol), 5 mol% bis(triphenylphosphine) palladium dichloride, and DMF (100 mL) to a 250 mL single-necked flask, purge with nitrogen three times, and heat to 100 °C to react overnight.

[0093] The reaction solution was quenched in water, filtered, the solid was collected and dried, and recrystallized from toluene / ethanol to obtain intermediate S1-2 (yield 85%).

[0094] (1-3) Synthesis of intermediate S1-3: S1-2 was dissolved in dichloromethane at a ratio of 6 mL / g, 4 equivalents of iodine chloride were added, and the solution was stirred at 35°C for 23 hours. After cooling the reaction to room temperature and then cooling in a refrigerator, the precipitate was filtered off and washed with cold dichloromethane. The product was ready for use without further purification.

[0095] (1-4) Synthesis of intermediate S1-4: A flask equipped with a magnetic stirrer and 4 equivalents of malononitrile was evacuated and filled with nitrogen. After adding ethylene glycol dimethyl ether, the solution was cooled to 0°C, and 6 equivalents of sodium hydride were added over 15 minutes. The mixture was stirred at 0°C and room temperature for 15 minutes each, and S1-3 and 5 mol% tetraphenylphosphine palladium dichloride were added. After stirring under reflux overnight, the mixture was acidified with 1 mol hydrochloric acid to precipitate the product. The crude product was filtered, washed with water, dried to constant weight, dissolved in acetone, and filtered through a diatomaceous earth and silica gel column. After grinding in dichloromethane, the product was cooled in a refrigerator before filtering off the mother liquor. The solid was washed with cold dichloromethane until the filtrate was clear to give pure product S1-4 (yield 56%).

[0096] (1-5) Synthesis of compound I-4: A flask equipped with a magnetic stirrer was placed in S1-4 (100 mmol), evacuated, and rinsed with nitrogen. Dichloromethane and 1.15 equivalents of PIFA were added, the flask was covered with aluminum foil, and stirred at room temperature for three days. The solution was concentrated, and acetic acid was added at a DCM / HOAc ratio of 4:1. After stirring at room temperature for 1 hour and then at 10°C for 30 minutes, the product was filtered and washed with cold dichloromethane to obtain a high-purity final product (yield 31%) with a molecular weight of m / z = 457.08 as determined by mass spectrometry.

[0097] Synthesis Example 2: Synthesis of Compound I-7:

[0098] (1-1) Synthesis of intermediate S2-1: Add raw materials M2-1 (100 mmol), M1-2 (100 mmol), a 10:1 mixture of dialkyl / water, potassium phosphate (200 mmol), and 10 mol% SPhos to a 500 mL three-necked flask. Degas the mixture by sonication for 15 minutes, then add 5 mol% palladium(II) acetate. Purge the mixture with nitrogen three times and reflux for 16 hours.

[0099] The reaction mixture was diluted in a mixture of ethyl acetate and water. After separation, the aqueous phase was extracted with ethyl acetate, and the combined organic layers were dried over sodium sulfate, filtered through a diatomaceous earth column, and the solvent was evaporated. The crude product was purified by grinding in hexane overnight, filtering, and washing with cooled hexane. Intermediate S2-1 was given (85% yield).

[0100] Referring to the synthesis method in steps (1-3) to (1-5) of Example 1 above, only intermediate S1-2 was replaced with intermediate S2-1, intermediate S1-3 was replaced with intermediate S2-2, and intermediate S1-4 was replaced with intermediate S2-3 to obtain compound I-7, whose molecular weight m / z = 630.05 was determined by mass spectrometry.

[0101] Synthesis Example 3: Synthesis of Compound I-10:

[0102] (1-1) Synthesis of intermediate S2-1: Compound I-7 was obtained by referring to the synthesis method in Example 2 above.

[0103] (1-2) Synthesis of compound I-10: Compound I-7 (100 mmol) and deuterated dimethyl sulfoxide (600 mmol) were added to a 500 mL three-necked flask, stirred, and heated to an internal temperature of 75°C-80°C. The system dissolved and became clear. Trifluoromethanesulfonic acid (600 mmol) was then added to the system, and the mixture was purged with nitrogen three times. The mixture was then kept at 75°C-80°C and refluxed for 6 hours.

[0104] Incubate at 60°C, add K₂CO₃ aqueous solution (I₁₀:K₂CO₃:deionized water = 1:10:50), wash once with alkali, separate the layers, and concentrate the organic phase at atmospheric pressure until no solvent distills out. Add 1 L of toluene to the above system, dissolve and clear at room temperature, and pass through a silica gel column. After column chromatography, add 0.6 L of toluene to wash the column.

[0105] The above organic phase is concentrated under negative pressure, heated to 100℃ to melt the material, and then a vacuum distillation apparatus is set up with a distillation head having three spikes. The area around the distillation head is insulated with a heating belt. The liquid phase temperature is maintained at 120℃, the vacuum degree is ≥0.09Mpa, and the product with a gas phase temperature of 90-100℃ is collected.

[0106] After the reduced evaporation was completed, the collected product was heated until completely melted, keeping the heptane temperature below 50°C. The deuterated crude product was slowly poured into 3 times its volume of heptane while stirring the heptane to ensure uniform dispersion. After stirring for 0.5 h, the temperature was lowered to 20°C and filtered. Compound I-10 was obtained, and its molecular weight was determined to be 636.08 by mass spectrometry.

[0107] Synthesis Example 4: Synthesis of Compound I-17:

[0108] (1-1) Synthesis of intermediate S4-1: The raw materials M4-1 (100 mmol), M4-2 (110 mmol), 200 mL of dioxane, anhydrous potassium acetate (200 mmol), and 10 mol% bis(triphenylphosphine) palladium dichloride were added to a 500 mL three-necked flask, purged with nitrogen three times, heated to 104 °C, refluxed, and reacted for 6 hours.

[0109] After the reaction was completed, the temperature was lowered to 60°C, 6L of deionized water was added, the temperature was maintained at 60°C, and the mixture was stirred for 15 minutes. The aqueous phase was separated, extracted with 200mL of toluene, and combined with the organic phase. The solvent was removed by rotary evaporation, 1L of toluene was added, and the mixture was heated to 55-60°C to dissolve. The mixture was washed twice with 1L of water. The crude product was passed through a silica gel column at 50°C. The column was flushed with toluene, and the column solutions were combined and evaporated to remove the remaining solvent. Anhydrous ethanol was added, and the mixture was stirred for 20 min. The mixture was then placed in a cold storage and frozen for 2 h before being filtered to obtain intermediate S4-1 (yield 82.3%).

[0110] Referring to the synthesis method in steps (1-1) to (1-5) of Example 1 above, only the raw material M1-1 was replaced with the raw material M4-3, the intermediate S1-2 was replaced with the intermediate S4-3, the intermediate S1-3 was replaced with the intermediate S4-4, and the intermediate S1-4 was replaced with the intermediate S4-5 to obtain compound I-17, whose molecular weight m / z = 593.08 was determined by mass spectrometry.

[0111] Synthesis Example 5: Synthesis of Compound I-30:

[0112] (1-1) Synthesis of intermediate S5-1: Referring to the synthesis method in step (1-1) of Example 4 above, only the raw material M4-1 is replaced with raw material M5-1 to obtain intermediate S5-1.

[0113] Referring to the synthesis method in Example 2 above, only intermediate S2-1 was replaced with intermediate S5-2, intermediate S2-2 was replaced with intermediate S5-3, and intermediate S2-3 was replaced with intermediate S5-4 to obtain compound I-30, whose molecular weight m / z = 544.08 was determined by mass spectrometry.

[0114] Theoretical calculations: The LUMO values ​​of the compounds of this invention can be obtained by DFT calculation [B3LYP / 6-31G(d,p)]. Some related compounds and their LUMO values ​​are shown below:

[0115] It can be seen that the compounds of the present invention have greater potential and better application prospects in organic electroluminescent devices, whether as hole injection layer materials or p-dopant materials.

[0116] Device Example 1 First, the glass substrate, which has a 120 nm thick indium tin oxide (ITO) anode, is cleaned and then treated with UV ozone and oxygen plasma. After treatment, the substrate is dried in a nitrogen-filled glove box to remove moisture, and then mounted on a substrate holder and placed in a vacuum chamber. The organic layer is then deposited under a vacuum of approximately 10 nm. -8 Under torr conditions, the ITO anode was sequentially vapor-deposited at a rate of 0.01–5 Å / s through thermal vacuum, as follows: Compounds HT and M16 (98:2, w / w) were co-deposited as a hole injection layer (HIL) with a thickness of 100 Å. The compound HT was used as a hole transport layer (HTL) with a thickness of 400 Å. Compound EB was used as an electron blocking layer (EBL) with a thickness of 50 Å; The host material compound A and the dopant material compound RD (98:2, w / w) were co-deposited as the light-emitting layer (EML) with a thickness of 400 Å. Compound HB was used as a hole blocking layer (HBL) with a thickness of 50 Å. Compound ET and 8-hydroxyquinoline-lithium (Liq) (50:50, w / w) were co-deposited as an electron transport layer (ETL) with a thickness of 350 Å; The organic electroluminescent device is obtained by using 8-hydroxyquinoline-lithium (Liq) as the electron injection layer (EIL) with a thickness of 10 Å and aluminum as the cathode with a thickness of 1200 Å.

[0117] Device Examples 2-5, Device Comparative Example 1 The device was prepared according to the above-mentioned Example 1, except that the compound I-4 in the hole injection layer (HIL) was replaced with the compound in Table 2 with the same doping amount. The other layers, thicknesses, materials and preparation methods were the same as those in Example 1.

[0118] The material structures used in the device embodiments and device comparative examples provided above are shown below: , , , , , , , .

[0119] At 10 mA / cm 2 Under the conditions, the voltage (V), current efficiency (CE, cd / A), and lifetime (LT) of devices in Examples 1-5 and Comparative Example 1 were respectively tested. 97 The device was tested (h). The voltage test value, CE test value, and LT test value of Comparative Example 1 were compared. 97 The test value is recorded as 1.00. For device examples 1-5, the voltage test value, CE test value, and LT are their respective values. 97 The ratio of the test value to the test value of Comparison Example 1 (relative voltage, relative CE, relative lifetime). The test results are shown in Table 2: Table 2

[0120] As can be seen from Table 2, compared with the existing compound D1 as a dopant, the device fabricated using the compound of the present invention as a dopant for the hole injection layer has a lower voltage, higher current efficiency, and unexpectedly improved lifetime. This shows that the compound of the present invention brings excellent device performance, enabling the device to achieve higher current efficiency and lifetime, and significantly improving device performance. This proves the unique advantages of the compound of the present invention.

[0121] The preferred embodiments of the present invention have been described in detail above; however, the present invention is not limited thereto. Within the scope of the inventive concept, various simple modifications can be made to the technical solutions of the present invention, including combinations of various technical features in any other suitable manner. These simple modifications and combinations should also be considered as the content disclosed in the present invention and are all within the protection scope of the present invention.

Claims

1. A compound having the structure shown in Formula I: Equation I; in, L1 has the structure shown in Equation II: Formula II; L2 has the structure shown in Equation III: Formula III; Formula III Among them, the asterisk " "Indicates the position of combination, R1 and R2 are each independently selected from electron-withdrawing groups, wherein the electron-withdrawing groups are selected from halogens, nitrosyl, nitro, acyl, carbonyl, carboxylic acid, ester, -CN, -NC, -SCN, -OCN, -SF5, borane, sulfinyl, sulfonyl, phosphoxy, nitrogen-containing heteroaryl, or C1-C20 alkyl, C1-C20 heteroalkyl, C3-C20 cycloalkyl, C2-C20 heterocycloalkyl, C1-C20 alkoxy, C1-C20 alkylthio, C1-C20 alkylsilyl, C2- C20 alkenyl, C2-C20 alkynyl, C6-C30 aryl, C3-C30 heteroaryl, C6-C30 aryloxy, C3-C30 heteroaryloxy, C6-C30 arylthio, C3-C30 heteroarylthio, C7-C30 arylalkyl, C6-C30 arylsilyl, wherein R' is selected from the group consisting of: deuterium (D), halogen, nitrosyl, nitro, acyl, carbonyl, carboxylic acid, ester, -CN, -NC, -SCN, -OCN, -SF5, boroalkyl, sulfinyl, sulfonyl, phosphoxy, mercapto; R3 and R4 are each independently selected from H, deuterium (D), halogen, -CN, -CF3, partially fluorinated or perfluorinated C1-C4 alkyl groups, and SF5; R5 is independently selected from H, deuterium (D), halogen, -CN, -CF3, partially fluorinated or perfluorinated C1-C8 alkyl, C6-C30 aryl, C2-C30 heteroaryl, -SF5, wherein the C6-C30 aryl and C2-C30 heteroaryl are optionally substituted with substituents selected from the following: deuterium (D), halogen, CN, partially fluorinated C1-C4 alkyl, perfluorinated C1-C4 alkyl, -CF3; Xn1 is selected from N or CRn4; Rn1, Rn2, Rn3, and Rn4 are each independently selected from H, deuterium (D), halogen, nitroso, nitro, acyl, carbonyl, carboxylic acid, ester, -CN, isocyanate, -SCN, -OCN, -SF5, borane, sulfinyl, sulfonyl, phosphoxy, mercapto, C1-C20 alkyl, C1-C20 heteroalkyl, C3-C20 cycloalkyl, C2-C20 heterocycloalkyl, C1-C20 alkoxy, C1-C20 alkylthio, C1-C20 alkylsilyl, C2-C20 alkenyl, C2-C2 C6-C30 aryl, C3-C30 heteroaryl, C6-C30 aryloxy, C3-C30 heteroaryloxy, C6-C30 arylthio, C3-C30 heteroarylthio, C7-C30 arylalkyl, C6-C30 arylsilyl, wherein C1-C20 alkyl, C1-C20 heteroalkyl, C3-C20 cycloalkyl, C2-C20 heterocycloalkyl, C1-C20 alkoxy, C1-C20 alkylthio, C1-C20 alkylsilyl, C2-C20 alkenyl, C2-C20 alkynyl, C6- C30 aryl, C3-C30 heteroaryl, C6-C30 aryloxy, C3-C30 heteroaryloxy, C6-C30 arylthio, C3-C30 heteroarylthio, C7-C30 arylalkyl, and C6-C30 arylsilyl may optionally be substituted with the following substituents: deuterium (D), halogen, nitroso, nitro, acyl, carbonyl, carboxylic acid, ester, -CN, -NC, -SCN, -OCN, -SF5, boranealkyl, sulfinyl, sulfonyl, phosphoxy, mercapto, C1-C20 alkyl, and C1-C20 heteroalkyl. C3-C20 cycloalkyl, C2-C20 heterocycloalkyl, C1-C20 alkoxy, C1-C20 alkylthio, C1-C20 alkylsilyl, C2-C20 alkenyl, C2-C20 alkynyl, C6-C30 aryl, C3-C30 heteroaryl, C6-C30 aryloxy, C3-C30 heteroaryloxy, C6-C30 arylthio, C3-C30 heteroarylthio, C7-C30 arylalkyl, C6-C30 arylsilyl; wherein adjacent Rn2 and Rn4 are not connected or are linked by chemical bonds to form a ring.

2. The compound according to claim 1, characterized in that, The compound satisfies one or more of the following conditions: (1a) Compound I contains at least two and no more than eight -CN groups; (2a) The electron-withdrawing group is selected from the group consisting of: halogen, C1-C8 haloalkyl, C1-C8 haloalkoxy, -SF5, sulfonyl, -CN, -NC, -SCN, -OCN, C3-C12 nitrogen-containing heteroaryl; (3a) The electron-withdrawing group is selected from the group consisting of: F, -CF3, -OCF3, -SF5, -SO2CF3, -NC, -SCN, -SCN, -OCN, pyrimidinyl, triazineyl.

3. The compound according to claim 1, characterized in that, The compound satisfies one or more of the following conditions: (1b) R1 and R2 are each independently selected from -CN, -CF3, partially fluorinated or perfluorinated C1-C8 alkyl, -SF5, halogen, C6-C30 aryl, C2-C30 heteroaryl; the C6-C30 aryl and C2-C30 heteroaryl are optionally substituted with substituents selected from the following: deuterium (D), partially fluorinated or perfluorinated C1-C8 alkyl, -CF3, halogen, -SF5, -CN; (2b) R1 and R2 are each independently selected from -CN, partially fluorinated C1-C4 alkyl or perfluorinated C1-C4 alkyl, -CF3, C6-C24 aryl, C3-C24 heteroaryl; the C6-C24 aryl and C3-C24 heteroaryl are optionally substituted with substituents selected from the following: deuterium (D), partially fluorinated C1-C4 alkyl or perfluorinated C1-C4 alkyl, -CF3, halogen, F, -CN; (3b) At least one of R1 and R2 is selected from -CN or -CF3; (4b) Both R1 and R2 are -CN.

4. The compound according to claim 1, characterized in that, The compound satisfies one or more of the following conditions: (1c) R3 and R4 are each independently selected from H, deuterium (D), -CN, partially fluorinated C1-C4 alkyl, perfluorinated C1-C4 alkyl or -CF3; (2c) R3 and R4 are each independently selected from H, deuterium (D), -CN, and -CF3; (3c) R3 and R4 are each independently selected from H and deuterium (D); (4c) R5 is selected from H, deuterium (D), halogen, -CN, partially fluorinated C1-C4 alkyl, perfluorinated C1-C4 alkyl, -CF3 C6-C24 aryl, C3-C24 heteroaryl; said C6-C24 aryl, C3-C24 heteroaryl are optionally substituted with substituents selected from the following: deuterium (D), halogen, CN, partially fluorinated C1-C4 alkyl, perfluorinated C1-C4 alkyl, -CF3; (5c) R5 is selected from H, deuterium (D), F, -CN, partially fluorinated C1-C4 alkyl, perfluorinated C1-C4 alkyl, -CF3 C6-C18 aryl, C3-C18 heteroaryl; said C6-C18 aryl, C3-C18 heteroaryl are optionally substituted with substituents selected from the following: deuterium (D), halogen, CN, partially fluorinated C1-C4 alkyl, perfluorinated C1-C4 alkyl, -CF3; (6c) R5 is selected from H, deuterium (D), -CN, -CF3, C6 aryl, C4-C5 heteroaryl, wherein the C6 aryl and C4-C5 heteroaryl are optionally substituted by substituents selected from the following: deuterium (D), halogen, CN, partially fluorinated C1-C4 alkyl, perfluorinated C1-C4 alkyl, -CF3.

5. The compound according to claim 1, characterized in that, The compound satisfies one or more of the following conditions: (1d) At least one of Rn1, Rn2, Rn3, and Rn4 has one or more electron-withdrawing groups; (2d) The group is selected from any one of the following groups: pyridyl, pyrimidinyl, triazinyl, pyrazinyl, pyridazinyl, quinolinyl, isoquinolinyl, quinoxalinyl, quinazolinyl, benzimidazolyl, phenanthrolineyl, wherein the pyridyl, pyrimidinyl, triazinyl, pyrazinyl, pyridazinyl, quinolinyl, isoquinolinyl, quinoxalinyl, quinazolinyl, benzimidazolyl, phenanthrolineyl is optionally substituted by a substituent selected from the following: -CN, -CF3, -F; (3d)Rn4 is a group having at least one or more electron-withdrawing groups; (4d)Xn1 is CRn4.

6. The compound according to claim 1, characterized in that, R5 is selected from the group consisting of the following structures A1 to A105. Indicates the linkage site of the functional group: Preferably, R5 is selected from structures A1 to A80; More preferably, R5 is selected from structures A1 to A50; More preferably, R5 is selected from structures A1 to A41.

7. The compound according to claim 1, characterized in that, R1 and R2 are the same and selected from -CN, and the compound has the structure shown in Formula I-1: Equation I-1; Preferably, R3 and R4 are the same and are selected from H or deuterium (D); More preferably, the compound has the structure shown in Formula I-2: Equation I-2; More preferably, Xn1 is selected from formula CRn4; More preferably, Rn1, Rn2, Rn3, and Rn4 are each independently selected from H, deuterium (D), halogen, F, -CN, partially fluorinated C1-C8 alkyl or perfluorinated C1-C8 alkyl, -CF3, C6-C30 aryl, and C3-C30 heteroaryl, wherein the C6-C30 aryl and C3-C30 heteroaryl are optionally substituted with substituents selected from the following: deuterium (D), halogen, CN, partially fluorinated C1-C4 alkyl, perfluorinated C1-C4 alkyl, and -CF3; and wherein at least one of Rn1, Rn2, Rn3, and Rn4 is selected from partially fluorinated C1-C8 alkyl or perfluorinated C1-C8 alkyl, halogen, and -CN, and adjacent Rn2 and Rn4 are not connected or are linked by chemical bonds to form a ring.

8. The compound according to claim 1, characterized in that, The compounds are selected from the group consisting of compounds I-1 to I-57: 。 9. The use of the compound according to any one of claims 1 to 8 in organic electronic devices; Preferably, the organic electronic device is an organic electroluminescent device; More preferably, the organic electroluminescent device includes an organic semiconductor layer, the organic semiconductor layer comprising the compound according to any one of claims 1 to 8; More preferably, the organic electronic device is an organic light-emitting diode.

10. An organic electroluminescent device, comprising a first electrode, a second electrode, and at least one organic layer disposed between the first electrode and the second electrode, said organic layer comprising at least one compound as described in any one of claims 1 to 8; Preferably, the organic layer comprises a hole injection layer and / or a hole transport layer, wherein the hole injection layer and / or the hole transport layer comprises at least one compound as described in any one of claims 1 to 8; More preferably, the organic layer further includes at least one of a light-emitting layer, an electron blocking layer, a hole blocking layer, an electron transport layer, and an electron injection layer.

11. The organic electroluminescent device according to claim 10, characterized in that, The compound according to any one of claims 1 to 8 is used in the hole injection layer in an amount of 1% to 100% of the total weight of the hole injection layer; Preferably, when the compound of any one of claims 1 to 8 is combined with other compounds in the hole injection layer, the amount of the compound of any one of claims 1 to 8 in the hole injection layer is 1% to 99% of the total weight of the hole injection layer, more preferably 1% to 10%.

12. The organic electroluminescent device according to claim 10, characterized in that, The hole injection layer and / or hole transport layer further comprises at least one hole transport material; Preferably, the hole transport material comprises at least one of the following: triarylamine compound, spirodifluorene compound, pentanebenzene compound, oligothiophene compound, oligophenyl compound, oligophenylene vinylidene compound, oligofluorene compound, porphyrin complex, and metal phthalocyanine complex; More preferably, the molar doping ratio of the compound according to any one of claims 1 to 8 to the hole transport material is 10000:1 to 1:10000, and even more preferably 10:1 to 1:

100.

13. The organic electroluminescent device according to claim 10, characterized in that, The organic electroluminescent device includes an anode, a cathode, and a plurality of stacked layers disposed between the anode and the cathode. The stacked layers include a first stacked layer and a second stacked layer. The first stacked layer includes a first light-emitting layer, and the second stacked layer includes a second light-emitting layer. A charge-generating layer is disposed between the first stacked layer and the second stacked layer. The charge-generating layer includes a p-type charge-generating layer and an n-type charge-generating layer. The p-type charge-generating layer includes an organic compound according to any one of claims 1 to 8. Preferably, the p-type charge generation layer further comprises at least one hole transport material; Preferably, the hole transport material comprises a triarylamine compound, a spirodifluorene compound, a pentanebenzene compound, an oligothiophene compound, an oligophenyl compound, an oligophenylene vinylidene compound, an oligofluorene compound, a porphyrin complex, or a metal phthalocyanine complex; Preferably, the molar doping ratio of the compound according to any one of claims 1 to 8 to the hole transport material is 10000:1 to 1:10000, more preferably 10:1 to 1:100; Preferably, the charge generation layer further comprises a buffer layer disposed between the p-type charge generation layer and the n-type charge generation layer, the buffer layer comprising the compound of any one of claims 1-8.

14. A display component comprising the organic electroluminescent device according to any one of claims 10 to 13; Preferably, the display component is selected from at least one of the following: flat panel display, monitor, medical monitor, television set, billboard, lamp for indoor or outdoor lighting and / or signaling, head-up display, fully or partially transparent display, flexible display, smartphone, tablet computer, tablet phone, wearable device, smartwatch, laptop computer, digital camera, portable camcorder, viewfinder, microdisplay, 3D display, vehicle display, and taillight.

Images