Compounds and uses thereof

Abstract

The application discloses a compound and application thereof, and belongs to the technical field of display. The chemical structural formula of the compound is shown in the following: A is O, S, CR1R2; Ar1-Ar3 are each independently selected from one of hydrogen, protium, deuterium, tritium, substituted or unsubstituted C1-C18 alkyl, substituted or unsubstituted C6-C30 aryl, and substituted or unsubstituted C3-C30 heteroaryl; R, R1 and R2 are each independently selected from one of hydrogen, deuterium, substituted or unsubstituted C1-C18 alkyl, substituted or unsubstituted C6-C30 aryl, and substituted or unsubstituted C3-C30 heteroaryl; n represents an integer of 0-7; and the compound is suitable for preparing an electron transport layer or an n-type charge generation layer of an OLED device, so that the efficiency and the service life of the device are improved, and the voltage of the device is reduced.

Description

Technical Field

[0001] This invention relates to the field of display technology, and in particular to compounds and their applications. Background Technology

[0002] Organic light-emitting devices (OLEDs), also known as organic light-emitting diodes, have advantages such as self-illumination, low power consumption, wide viewing angle, light weight, thinness, fast response, high contrast, low driving voltage, and flexibility, and are widely used in the fields of displays and lighting.

[0003] OLED devices include single-layer devices and tandem OLEDs. Tandem OLEDs, also known as stacked OLEDs, typically use at least two electroluminescent cells (OLEDs) with the same or different emission colors stacked in series to achieve high luminous brightness at relatively low operating current densities. Adjacent OLED cells are connected by a charge generating layer (CGL), which is fabricated from a charge transport material. The charge transport material has a significant impact on the operating voltage, efficiency, and lifetime of OLED devices, making it necessary to provide a charge transport material that can improve device efficiency and lifetime while reducing operating voltage. Summary of the Invention

[0004] In view of this, the present invention provides a compound and its application, which can solve the technical problems existing in related technologies. Specifically, it includes the following technical solutions: On the one hand, a compound is provided, the chemical structural formula of which is shown below:

[0005] Where A represents O, S, and CR1R2; Ar1-Ar3 are each independently selected from one of hydrogen, protium, deuterium, tritium, substituted or unsubstituted C1-C18 alkyl, substituted or unsubstituted C6-C30 aryl, or substituted or unsubstituted C3-C30 heteroaryl. R, R1, and R2 are each independently selected from one of hydrogen, protium, deuterium, tritium, substituted or unsubstituted C1-C18 alkyl, substituted or unsubstituted C6-C30 aryl, or substituted or unsubstituted C3-C30 heteroaryl. n represents an integer from 0 to 7.

[0006] In some possible implementations, R is deuterium, substituted or unsubstituted C1-C8 alkyl, or substituted or unsubstituted C6-C10 aryl.

[0007] In some possible implementations, Ar1-Ar3 are each independently selected from one of hydrogen, protium, deuterium, tritium, substituted or unsubstituted C1-C8 alkyl, substituted or unsubstituted C6-C10 aryl, substituted or unsubstituted C3-C10 heteroaryl, and the heteroatom in the heteroaryl is an N atom or an S atom.

[0008] In some possible implementations, Ar1-Ar3 are all substituted or unsubstituted C6-C10 aryl groups; or, Two of Ar1-Ar3 are substituted or unsubstituted C6-C10 aryl groups, and the other is a substituted or unsubstituted C3-C10 heteroaryl group; or, Two of Ar1-Ar3 are hydrogen, protium, deuterium or tritium, and the other is a substituted or unsubstituted C6-C10 aryl or a substituted or unsubstituted C3-C10 heteroaryl.

[0009] In some possible implementations, when the aryl or heteroaryl group includes a substituent, the substituent includes at least one of methyl, propyl, butyl, or nitrile.

[0010] On the other hand, a charge transport material is provided, the charge transport material comprising the above-described compound.

[0011] On the other hand, the applications of the above compounds in organic electroluminescent devices, organic solar cells, organic thin-film transistors, organic photodetectors, organic field-effect transistors, organic integrated circuits, or organic photosensors are provided.

[0012] In another aspect, an organic electroluminescent device is provided, the organic electroluminescent device comprising: a first electrode, a second electrode, and a light-emitting unit disposed between the first electrode and the second electrode; The light-emitting unit includes at least an electron transport layer, which comprises the charge transport material described above.

[0013] In another aspect, an organic electroluminescent device is provided, the organic electroluminescent device comprising: a first electrode, a second electrode, and a plurality of light-emitting units disposed between the first electrode and the second electrode; Between any two adjacent light-emitting units there is a charge-generating layer, the charge-generating layer including an n-type doped layer, the n-type doped layer including the charge transport material described above.

[0014] In some possible implementations, the n-type doped layer further includes a dopant, which is at least one of an alkali metal, an alkaline earth metal, and a rare earth metal, and the mass percentage of the dopant in the n-type doped layer is 0.5%-50%.

[0015] The beneficial effects of the technical solutions provided in the embodiments of the present invention include at least the following: The compounds provided in this invention include bridging groups, and o-phenanthroline and pyrazine groups connected to the bridging groups. The bridging groups are selected from fluorene groups, dibenzofuran groups, or dibenzothiophene groups. The synergistic effect of these various groups enables these compounds to be used as electron transport materials or charge generation materials in OLED devices, exhibiting the following advantages: (1) High electron mobility, which helps improve the voltage of OLED devices, especially the turn-on voltage and current efficiency. (2) Suitable HOMO and LUMO energy levels, which can reduce the carrier injection barrier, lower the voltage of OLED devices, and improve device efficiency. (3) High T1 energy level, which, when used as an n-type charge generation material, ensures the energy transfer efficiency between the host material and the guest light-emitting material and suppresses energy loss. (4) High glass transition temperature, which is beneficial to improving the phase stability and high-temperature stability of the film made from the compound, thereby improving the lifetime of OLED devices (including high-temperature lifetime). Detailed Implementation

[0016] The technical solutions in the embodiments of the present invention will be clearly and completely described below. Obviously, the described embodiments are only some, not all, of the embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0017] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains. The terminology used in this specification is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention.

[0018] Organic light-emitting devices (OLEDs), also known as organic light-emitting diodes, have advantages such as self-illumination, low power consumption, wide viewing angle, light weight, thinness, fast response, high contrast, low driving voltage, and flexibility, and are widely used in the fields of displays and lighting.

[0019] OLED devices are typically fabricated by vacuum evaporation or spin-coating of multiple layers of organic material between two electrodes, resulting in a sandwich-like multilayer structure. For example, an OLED device includes a conductive glass anode and a metal cathode, as well as a light-emitting unit disposed between them. Along the direction close to the metal cathode, the light-emitting unit includes a hole injection layer, a hole transport layer, a light-emitting layer, an electron transport layer, and an electron injection layer stacked together.

[0020] The working mechanism of an OLED device is as follows: Under the action of an applied electric field, holes generated by the anode and electrons generated by the cathode are injected through the hole (electron) injection layer, then transported through the hole (electron) transport layer, and recombine in the emissive layer to generate excitons. The excitons excite the ground-state electrons in the emissive material of the emissive layer to the excited state, and finally the excited-state electrons return to the ground state, thus emitting light. The color (wavelength) of light emitted by an OLED device can be adjusted by changing the material of the emissive layer; for example, it can emit red, green, blue, and white light.

[0021] OLED devices are driven by current; the higher the current density, the higher the brightness. Typically, to achieve the high brightness required for practical applications, OLED devices must operate at high current densities for extended periods, preventing them from operating within their most efficient brightness range. More importantly, this significantly shortens the lifespan of OLED devices. Therefore, achieving both high luminous brightness and high current efficiency while operating at low current densities would significantly extend the lifespan of OLED devices, an effect that multilayer OLED devices can achieve.

[0022] A stacked OLED device includes two or more light-emitting units connected in series and stacked. The light emitted by the multiple light-emitting units may be the same or different, and any two adjacent light-emitting units are connected by a charge generating layer (CGL). The multiple light-emitting units do not affect each other.

[0023] In traditional OLED devices, electrons and holes injected from the two electrodes recombine in the light-emitting region to form excitons; a pair of electron-hole pairs can only form one pair of excitons. In stacked OLED devices, taking a bilayer example, the injected electrons and holes recombine with the electrons and holes generated in the CGL layer in the two light-emitting layers, forming two pairs of excitons.

[0024] Therefore, compared to traditional OLED devices, stacked OLEDs can achieve higher luminous intensity at the same current density, and the current efficiency can increase exponentially with the increase in the number of stacked light-emitting units. In other words, at the same brightness, the operating current density of stacked light-emitting units can be lower, thus significantly improving their lifetime. Furthermore, since each light-emitting unit in a stacked OLED emits light normally, the emission spectrum of the stacked OLED is the superposition of the emission spectra of all the light-emitting units.

[0025] For stacked OLED devices, the selection of the CGL layer used to connect each light-emitting subunit is crucial. The charge generation layer, i.e. the charge transport material, has an important impact on the operating voltage, efficiency, and lifetime of the OLED device. It is necessary to provide a charge transport material that can improve device efficiency and lifetime while reducing device operating voltage.

[0026] To address the aforementioned technical problems, a first aspect of this invention provides a compound, the chemical structural formula of which is shown below:

[0027] Ar1-Ar3 are each independently selected from one of hydrogen, protium, deuterium, tritium, substituted or unsubstituted C1-C18 alkyl, substituted or unsubstituted C6-C30 aryl, or substituted or unsubstituted C3-C30 heteroaryl.

[0028] R, R1, and R2 are each independently selected from one of hydrogen, protium, deuterium, tritium, substituted or unsubstituted C1-C18 alkyl, substituted or unsubstituted C6-C30 aryl, or substituted or unsubstituted C3-C30 heteroaryl.

[0029] n represents an integer from 0 to 7. That is, the R group can be 0 or can replace any hydrogen atom on the phenanthroline group. When the R group is a non-hydrogen group, n is an integer from 1 to 7, that is, it can be 1, 2, 3, 4, 5, 6 or 7, to replace 1 to 7 hydrogen atoms on the phenanthroline group.

[0030] It should be noted that the "C1-C18 alkyl" involved in the embodiments of the present invention refers to a straight-chain or branched saturated hydrocarbon containing 1 to 18 carbon atoms. Further, the alkyl group can be a C1-C10 alkyl group, for example, it can be methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, tert-butyl, sec-butyl, 1-methylbutyl, 1-ethylbutyl, n-pentyl, isopentyl, neopentyl, n-hexyl, 1-methylpentyl, 2-methylpentyl, 4-methylpentyl, 3,3-dimethylbutyl, 2-ethylbutyl, heptyl, n-octyl, tert-octyl, 1-methylheptyl, 2-ethylhexyl, 2-propylpentyl, n-nonyl, 2,2-dimethylheptyl, 1-ethylpropyl, 1,1-dimethylpropyl, isohexyl, 4-methylhexyl, 5-methylhexyl, etc.

[0031] In this invention, the term "aryl" refers to an aromatic hydrocarbon group derived from an aromatic ring compound by removing one hydrogen atom. This can be a monocyclic aryl, a fused-ring aryl, or a polycyclic aryl. For polycyclic compounds, at least one ring must be an aromatic ring system. For example, "C6-C30 aryl" refers to an aryl group containing 6-30 carbon atoms. Each occurrence can be independently of C5, C6, C7, C8, C9, C10, C12, C14, C18, C20, C25, or C30 aryl. Suitable examples include, but are not limited to, benzene, biphenyl, naphthalene, anthracene, o-phenanthroline, dinaphthalene, triphenylene oxide, and their derivatives. Understandably, multiple aryl groups can also be interrupted by short non-aromatic units (e.g., <10% non-H atoms, such as C, N, or O atoms), specifically acenaphthene, fluorene, or 9,9-diarylfluorene, triarylamine, and diaryl ether systems should also be included in the definition of aryl.

[0032] In the embodiments of this invention, "heteroaryl" refers to an aryl group in which at least one carbon atom is replaced by a non-carbon atom, which can be an N atom, an O atom, an S atom, etc. For example, "C3~C30 heteroaryl" refers to a heteroaryl group containing 3 to 30 carbon atoms, and each occurrence can be independently C3 heteroaryl, C4 heteroaryl, C5 heteroaryl, C6 heteroaryl, C7 heteroaryl, C8 heteroaryl, C9 heteroaryl, C10 heteroaryl, C11 heteroaryl, C12 heteroaryl, C14 heteroaryl, C18 heteroaryl, C20 heteroaryl, C25 heteroaryl, and C30 heteroaryl. Suitable examples include, but are not limited to: furan, benzofuran, thiophene, benzothiophene, pyrrole, pyrazole, triazole, imidazole, oxazole, oxadiazole, thiazole, tetraazole, indole, carbazole, pyrroloimidazole, pyrrolopyrrole, thienopyrrole, thienothiophene, furanolopyrrole, furanolofuran, thienofuran, benzoisoxazole, benzoisothiazolium, benzimazole, pyridine, pyrazine, pyrimidine, triazine, quinoline, isoquinoline, o-diazonyl, quinoxaline, o-phenanthridine, primidine, quinazoline, and quinazolineone. Understandably, "azaaryl" refers to a heteroaryl group whose non-carbon atom is an nitrogen atom.

[0033] When A is O, the corresponding chemical structural formula of the compound is as follows:

[0034] When A is S, the corresponding chemical structural formula of the compound is as follows:

[0035] When A is CR1R2, the corresponding chemical structural formula of the compound is as follows:

[0036] The compounds provided in this invention include bridging groups, and o-phenanthroline and pyrazine groups connected to the bridging groups. The bridging groups are selected from fluorene groups, dibenzofuran groups, or dibenzothiophene groups. The synergistic effect of these various groups enables these compounds to be used as electron transport materials or charge generation materials in OLED devices, exhibiting the following advantages: (1) High electron mobility, which helps improve the voltage of OLED devices, especially the turn-on voltage and current efficiency. (2) Suitable HOMO and LUMO energy levels, which can reduce the carrier injection barrier, lower the voltage of OLED devices, and improve device efficiency. (3) High T1 energy level, which, when used as an n-type charge generation material, ensures the energy transfer efficiency between the host material and the guest light-emitting material and suppresses energy loss. (4) High glass transition temperature, which is beneficial to improving the phase stability and high-temperature stability of the film made from the compound, thereby improving the lifetime of OLED devices (including high-temperature lifetime).

[0037] In particular, by selecting a pyrazine group or its derivative as one of the end groups of the compound, there is a significant advantage in enhancing the compound's electron transport and charge injection capabilities.

[0038] The o-phenanthroline group can be unsubstituted or substituted with an R group, for example, R can be deuterium, which has the advantage of reducing vibrational energy loss in the compound.

[0039] R can also be a C1-C8 alkyl group, which not only simplifies the results of the compound but also has the advantages of improving the solubility of the compound and regulating intermolecular interactions.

[0040] R can also be a C6-C10 aryl group, which not only simplifies the results of the compound but also has the advantages of adjusting the energy level of the compound and improving the conductivity of the material.

[0041] In some examples, Ar1-Ar3 are each independently selected from hydrogen, protium, deuterium, tritium, substituted or unsubstituted C1-C8 alkyl (e.g., methyl, ethyl, propyl, butyl, etc.), substituted or unsubstituted C6-C10 aryl (phenyl, biphenyl, naphthyl, anthracene, phenanthrene, fluorene, etc.), and substituted or unsubstituted C3-C10 heteroaryl, wherein the heteroatom in the heteroaryl is an N atom or an S atom (e.g., pyrrole group and its derivatives, thiophene group and its derivatives, etc.).

[0042] Ar1-Ar3 are selected from the above groups and have significant advantages in improving the stability of compounds as well as their charge transport and injection capabilities.

[0043] Furthermore, to better achieve the above effect, one example is that all three Ar1-Ar3 are substituted or unsubstituted C6-C10 aryl groups. Another example is that two of Ar1-Ar3 are substituted or unsubstituted C6-C10 aryl groups, and the third is a substituted or unsubstituted C3-C10 heteroaryl group. Yet another example is that two of Ar1-Ar3 are hydrogen, protium, deuterium, or tritium, and the third is a substituted or unsubstituted C6-C10 aryl group or a substituted or unsubstituted C3-C10 heteroaryl group.

[0044] For the compounds provided in the embodiments of the present invention, the "substituted or unsubstituted C6-C30 aryl" and "substituted or unsubstituted C3-C30 heteroaryl" refer to a substituent, where the aryl or heteroaryl includes a substituent, and the substituent includes at least one of methyl, propyl, butyl, or nitrile. For example, for any one of Ar1-Ar3, the substituent may be a nitrile.

[0045] Regarding the compounds mentioned above, some examples of these compounds are listed below, see compounds 1-296.

[0046]

[0047] Secondly, embodiments of the present invention also provide a charge transport material, which includes any of the compounds mentioned above. That is, embodiments of the present invention provide the application of the above-mentioned compounds in charge transport materials.

[0048] The charge transport material provided in this embodiment of the invention has all the advantages of the compounds involved in this embodiment of the invention.

[0049] In some examples, the charge transport material can also serve as an electron transport material, for instance, when an adamantyl group is introduced into the nitrogen heterocyclic group containing Z1-Z3.

[0050] In other examples, the charge transport material can serve as a charge generation layer material, for instance, when a dibenzo5-membered heterocyclic group is introduced into the nitrogen heterocyclic group containing Z1-Z3.

[0051] Thirdly, embodiments of the present invention provide the application of any of the above-mentioned compounds in organic electroluminescent devices, organic solar cells, organic thin-film transistors, organic photodetectors, organic field-effect transistors, organic integrated circuits, or organic photoreceptors.

[0052] Fourthly, embodiments of the present invention provide an organic electroluminescent device, which includes: a first electrode, a second electrode, and a light-emitting unit disposed between the first electrode and the second electrode.

[0053] The light-emitting unit includes at least an electron transport layer, which includes the charge transport material mentioned above.

[0054] The organic electroluminescent device provided in the embodiments of the present invention has all the advantages of the compounds involved in the embodiments of the present invention.

[0055] When the above-mentioned compound is applied to the electron transport layer, the electron transport material corresponding to the electron transport layer may include 100 wt% of the above-mentioned compound. Alternatively, the electron transport material corresponding to the electron transport layer may include the above-mentioned compound and other electron transport materials, such as LiQ, to optimize its electron transport performance. For example, the mass ratio of the compound to LiQ may be 0.5-2:1.

[0056] In one example, the organic electroluminescent device includes: a first electrode, a second electrode, a hole transport layer, a light-emitting layer, and an electron transport layer disposed between the first electrode and the second electrode and arranged in sequence.

[0057] In one example, the organic electroluminescent device includes: a first electrode, a second electrode, and a light-emitting unit disposed between the first electrode and the second electrode, wherein the light-emitting unit includes a hole transport layer, a light-emitting layer and an electron transport layer arranged in sequence.

[0058] In another example, the organic electroluminescent device includes: a first electrode, a second electrode, and a light-emitting unit disposed between the first electrode and the second electrode. The light-emitting unit includes a hole injection layer, a hole transport layer, a light-emitting layer, an electron transport layer, and an electron injection layer arranged in sequence. Based on this example, only one of the hole injection layer and the hole transport layer may be provided, and / or only one of the electron transport layer and the electron injection layer may be provided.

[0059] In another example, the organic electroluminescent device includes: a first electrode, a second electrode, and a light-emitting unit disposed between the first and second electrodes. The light-emitting unit includes a hole injection layer, a hole transport layer, an electron blocking layer, a light-emitting layer, a hole blocking layer, an electron transport layer, and an electron injection layer arranged in sequence. Based on this example, the hole injection layer, the hole transport layer, and the electron blocking layer may be provided with only one or any two of them, and / or the hole blocking layer, the electron transport layer, and the electron injection layer may be provided with only one or any two of them.

[0060] Fifthly, embodiments of the present invention provide an organic electroluminescent device, which includes: a first electrode, a second electrode, and a plurality of light-emitting units disposed between the first electrode and the second electrode. A charge generation layer is provided between any two adjacent light-emitting units, the charge generation layer including an n-type doped layer, the n-type doped layer including the charge transport material described above.

[0061] The organic electroluminescent device provided in the embodiments of the present invention, namely the stacked organic electroluminescent device, has all the advantages of the compounds involved in the embodiments of the present invention.

[0062] Furthermore, the charge generation layer also includes a p-type doped layer and a spacer layer located between the n-type doped layer and the p-type doped layer.

[0063] In this context, the arrangement of multiple light-emitting units disposed between the first and second electrodes can be identical or different, depending on the actual requirements. In some examples, multiple light-emitting units can share an electron injection layer and a hole injection layer; that is, the electron injection layer is located on the cathode side of the outermost light-emitting unit, and the hole injection layer is located on the anode side of the other outermost light-emitting unit.

[0064] Taking an organic electroluminescent device containing two light-emitting units as an example, the organic electroluminescent device includes a cathode, an electron injection layer, an electron transport layer, a second light-emitting layer, an electron blocking layer, a hole transport layer, a p-type doped layer, a spacer layer, an n-type doped layer, an electron transport layer, a first light-emitting layer, an electron blocking layer, a hole transport layer, a hole injection layer, and an anode, which are stacked sequentially.

[0065] In some examples, the n-type doped layer also includes a dopant, which is at least one of an alkali metal, an alkaline earth metal, and a rare earth metal, and the mass percentage of the dopant in the n-type doped layer is 0.5%-50%.

[0066] For example, the dopant is at least one of Li, Na, Cs, Mg, Ca, Sr and Yb, and more specifically, at least one of Li and Yb, to optimize the electron injection and transport performance of the charge generation layer, while improving the device efficiency through synergy with pyrazine-containing charge transport materials.

[0067] The mass percentage of dopant in the n-type doped layer can be any of the following values ​​or any range of two values: 0.5%, 0.6%, 0.7%, 0.8%, 0.9%, 1%, 1.5%, 2%, 2.5%, 3%, 3.5%, 4%, 4.5%, 5%, 6%, 7%, 8%, 9%, 10%, 15%, 20%, 25%, 30%, 35%, 40%, 45%, 50%, etc. Further, the mass percentage of dopant in the n-type doped layer is 1%-20%.

[0068] It should be noted that the organic electroluminescent devices involved in the embodiments of the present invention can be prepared by vacuum evaporation, molecular beam evaporation, solvent-based dip coating, spin coating, rod coating or inkjet printing. Metal electrodes can be prepared by evaporation or sputtering.

[0069] In a sixth aspect, embodiments of the present invention also provide a display device, which includes the organic electroluminescent device provided in the fourth aspect of embodiments of the present invention or the organic electroluminescent device provided in the fifth aspect of embodiments of the present invention.

[0070] For example, the display device may be a mobile phone, tablet, laptop, wearable device, television, electronic screen, vehicle display, special display device, etc.

[0071] The specific embodiments of the present invention will now be described in more detail. While specific embodiments of the present invention are described below, it should be understood that the present invention can be implemented in various forms and should not be limited to the embodiments set forth herein. Where specific techniques or conditions are not specified in the embodiments, they are performed in accordance with the techniques or conditions described in the literature in the art or according to the product instructions. Reagents or instruments whose manufacturers are not specified are all conventional products that can be obtained commercially.

[0072] It should be noted that the serial numbers of the compounds provided in the following embodiments are the same as the compounds with the same serial numbers among the aforementioned compounds 1-296.

[0073] Example 1 Compound 1 was prepared in Example 1, and the preparation method is shown below: Preparation of intermediate C1:

[0074] Starting material A1 (10.0 g, 31.23 mmol), starting material B1 (3.25 g, 31.82 mmol), and triethylamine (60 mL) were added to a three-necked flask. Under nitrogen protection, 0.2 g (0.28 mmol) of di-triphenylphosphine palladium chloride and 0.06 g (0.32 mmol) of cuprous iodide were added, and the mixture was stirred for 3 h. After the reaction was complete, the mixture was filtered, the solvent was concentrated to dryness, and the crude product was separated by column chromatography using petroleum ether:dichloromethane (10:1-5:1, v / v) as the eluent. A white product, intermediate C1, was obtained, with a yield of 18.75 g and a yield of 95%. The relevant characterization is shown below: HRMS (ESI, m / z): [M+H] + calcd for: C 23 H 19 , 295.1481, found,295.1485. Anal.: calcd: C, 93.84; H, 6.16; found: C, 93.92; H, 6.07.

[0075] Preparation of intermediate D1:

[0076] Intermediate C1 (8.0 g, 27.17 mmol), tetrabutylammonium bromide (1.75 g, 5.43 mmol), and dichloromethane (80 mL) were added to a three-necked flask. Potassium permanganate (5.58 g, 35.31 mmol) and sodium bicarbonate (2.74 g, 32.62 mmol) dissolved in 80 mL of water were added dropwise to the dichloromethane solution of intermediate C1. After stirring for 3 h, the reaction was stopped. The reaction was quenched dropwise with sodium sulfite aqueous solution. The mixture was separated, dried, and the organic phase was separated by column chromatography using petroleum ether:dichloromethane (8:1-3:1, v / v) as the eluent to give 7.1 g of white solid, i.e., intermediate D1, with a yield of 80%. The relevant characterization is shown below: HRMS (ESI, m / z): [M+H] + calcd for: C 23 H 19 O2, 327.1380, found, 327.1382. Anal.: calcd:C, 84.64; H, 5.56; O, 9.86; found: C, 84.58; H, 5.65; O, 9.82.

[0077] Preparation of intermediate F1:

[0078] Intermediate D1 (7.0 g, 21.45 mmol), starting material E1 (4.56 g, 21.48 mmol), and glacial acetic acid (50 mL) were added to a flask and refluxed for 5 h. After the reaction was complete, the mixture was cooled, and the precipitated solid was filtered. The crude product was separated by column chromatography using petroleum ether:dichloromethane (10:1–5:1, v / v) as the eluent to give 8.5 g of a white solid, i.e., intermediate F1, with a yield of 79%. The relevant characterization is shown below: HRMS (ESI, m / z): [M+H] + calcd for: C 37 H 29 N2, 501.2325, found, 501.2323. Anal.: calcd: C, 88.77; H, 5.64; N, 5.60; found: C, 88.71; H, 5.68; N, 5.62.

[0079] Preparation of intermediate H1:

[0080] Intermediate F1 (8.0 g, 15.98 mmol) was dissolved in dichloroethane (80 mL), and liquid bromine (3.83 g, 23.97 mmol) was added dropwise. The mixture was refluxed for 5 h. After the reaction was completed, the reaction was quenched dropwise with sodium sulfite and sodium bicarbonate aqueous solution. The mixture was separated, dried, and the organic phase was concentrated to dryness. It was recrystallized from toluene and methanol until the liquid phase purity was greater than 99.5%, yielding 5.7 g of white solid, which was intermediate H1, with a yield of 61%. The relevant characterization is shown below: HRMS (ESI, m / z): [M+H] + calcd for: C 37 H 28 BrN2,579.1430, found, 579.1428. Anal.: calcd: C, 76.68; H, 4.70; Br, 13.79; N, 4.83; found: C, 76.60;

[0081] Preparation of intermediate J1:

[0082] Intermediate H1 (5 g, 8.63 mmol), starting material I1 (2.63 g, 10.36 mmol), anhydrous potassium acetate (1.69 g, 17.22 mmol), and anhydrous toluene (50 mL) were added to a three-necked flask. Under nitrogen protection, Pd(PPh3)2Cl2 (0.12 g, 0.17 mmol) was added, and the mixture was refluxed for 10 h. After the reaction was complete, the inorganic salts were filtered off, and the organic phase was concentrated to dryness. The crude product was separated by column chromatography using petroleum ether:dichloromethane (5:1-2:1, v / v) as the eluent to give 5.1 g of white solid, which was intermediate J1, with a yield of 89%. The relevant characterization is shown below: HRMS (ESI, m / z): [M+H] + calcd for: C 43 H 40 BN2O2, 627.3177, found, 627.3178. Anal.: calcd: C, 82.42; H, 6.27; B, 1.73; N, 4.47; O, 5.11; found: C, 82.48; 5.14.

[0083] Preparation of compound 1:

[0084] Starting material K1 (0.5 g, 1.49 mmol), intermediate J1 (0.98 g, 1.56 mmol), and potassium carbonate (0.31 g, 2.24 mmol) were added to a three-necked flask, followed by toluene (5 mL), ethanol (2.5 mL), and deionized water (2.5 mL). Under nitrogen protection, Pd(PPh3)2Cl2 (0.021 g, 0.03 mmol) was added, and the mixture was refluxed for 8 h. After the reaction was complete, the mixture was separated, the organic phase was washed with water until neutral, concentrated to dryness, and the crude product was separated by column chromatography using ethyl acetate:dichloromethane (1:10-3:1, v / v) as the eluent to give 0.73 g of white solid, which was compound 1, with a yield of 64%. The relevant characterization is shown below: HRMS (ESI, m / z): [M+H] + calcd for: C 55 H 39 N4, 755.3169, found, 755.3170. Anal.: calcd: C, 87.50; H, 5.07; N, 7.42; found: C, 87.61; H, 5.01; N, 7.36.

[0085] Examples 2-9 Examples 2-9 prepared compounds 3, 6, 38, and 85, respectively. Compounds 98, 166, 235, and 267. The preparation of the intermediate compounds involved are shown below: Intermediates C2-C3 were prepared using the same synthesis method as intermediate C1, except that the raw materials were different, as shown in Table 1.

[0086]

[0087] Other intermediates D2-D3 were prepared using the same synthesis method as intermediate D1, except that the raw materials were different. The raw materials used are shown in Table 2.

[0088]

[0089] Other intermediates F2-F3 were prepared using the same synthesis method as intermediate F1, except that the raw materials were different. The raw materials used are shown in Table 3.

[0090]

[0091] Other intermediates H2-H9 were prepared using the same synthesis method as intermediate H1, except that the raw materials were different. The raw materials used are shown in Table 4.

[0092]

[0093] Other intermediates J2-J9 were prepared using the same synthesis method as intermediate J1, except that the raw materials were different. The raw materials used are shown in Table 5.

[0094]

[0095] Preparation of intermediate N1:

[0096] Starting materials L1 (10.0 g, 42.04 mmol), M1 (5.56 g, 37.84 mmol), and potassium carbonate (8.72 g, 63.09 mmol) were added to a Yamaguchi flask, followed by toluene (100 mL), ethanol (50 mL), and deionized water (50 mL). Under nitrogen protection, Pd(PPh3)4 (0.5 g, 0.43 mmol) was added, and the mixture was refluxed and stirred for 5 h. After the reaction was complete, the liquid was separated, and the organic phase was concentrated to dryness. The crude product was separated by column chromatography using petroleum ether:dichloromethane (1:3-3:1, v / v) as the eluent to obtain a white solid, intermediate N1, with a yield of 4.5 g and a yield of 41%. The relevant characterization is shown below: HRMS (ESI, m / z): [M+H] + calcdfor: C 11 H7BrN3, 259.9818, found, 259.9815. Anal.: calcd: C, 50.80; H, 2.33; Br, 30.72; N, 16.16; found: C, 50.90;

[0097] Other intermediates N2-N6 were prepared using the same synthesis method as intermediate N1, except that the raw materials were different. The raw materials used are shown in Table 6.

[0098]

[0099] Preparation of intermediate Q1:

[0100] Intermediate N1 (4.0 g, 15.38 mmol), starting material P1 (3.84 g, 16.13 mmol), and potassium carbonate (3.19 g, 23.08 mmol) were added to a Yamaguchi flask, followed by toluene (40 mL), ethanol (20 mL), and deionized water (20 mL). Under nitrogen protection, Pd(PPh3)2Cl2 (0.22 g, 0.31 mmol) was added, and the mixture was refluxed and stirred for 5 h. After the reaction was complete, the liquid was separated, and the organic phase was concentrated to dryness. The crude product was separated by column chromatography using petroleum ether:dichloromethane (1:3-3:1, v / v) as the eluent to obtain a white solid, intermediate Q1, with a yield of 5.1 g and a yield of 89%. The relevant characterization is shown below: HRMS (ESI, m / z): [M+H] + calcdfor: C 26 H 20N3, 374.1652, found, 374.1654. Anal.: calcd: C, 83.62; H, 5.13; N, 11.25; found: C, 83.69; H, 5.10; N, 11.20.

[0101] Other intermediates Q2-Q6 were prepared using the same synthesis method as intermediate Q1, except that the raw materials were different. The raw materials used are shown in Table 7.

[0102]

[0103] Other compounds were prepared using the same synthetic method as compound 1, except that the raw materials were different. The raw materials used are shown in Table 8.

[0104]

[0105] Test case The physical and photoelectric properties of the compounds prepared in the above embodiments of the present invention were tested, and the test results are shown in Table 9:

[0106] It should be noted that the triplet energy level T1 is derived from Horiba's Fluorolog. The material was tested using a 3-series fluorescence spectrometer. The test sample was a 0.00002 mol / L toluene solution.

[0107] The glass transition temperature Tg was obtained by differential scanning calorimetry (Pyris Diamond (DSC 2920) differential scanning calorimeter) under nitrogen protection, with heating and cooling rates of 10 °C / min.

[0108] The highest occupied molecular orbital (HOMO) energy level was measured by the ionization energy testing system (AC-2) in an atmospheric environment.

[0109] LUMO = HOMO + Eg, where Eg was measured using a dual-beam UV-Vis spectrophotometer (model: Hatachi U2900).

[0110] Electron mobility was measured as follows: Single-charge devices were fabricated using various compounds and Liq as electron transport materials, and the results were measured using the space-charge-limited current (SCLC) method. The single-charge device consisted of a substrate / anode, a hole injection layer, an electron transport layer, an electron injection layer, and a cathode, stacked sequentially.

[0111] The fabrication method for a single electronic device is as follows: Substrate / Anode: The glass substrate with an ITO (Indium Tin Oxide)-Ag-ITO (Indium Tin Oxide) surface layer was cleaned twice in distilled water, followed by ultrasonic cleaning in a commercial cleaning agent for 30 minutes, and then repeatedly cleaned twice with distilled water and ultrasonically cleaned for 10 minutes each time. After cleaning, it was ultrasonically cleaned sequentially with ethanol, acetone, and isopropanol (5 minutes each time), and dried. It was then transferred to a plasma cleaner for 5 minutes, baked in a clean environment until all moisture was removed, cleaned with ultraviolet photosynthetic ozone, and then treated with oxygen plasma for 30 seconds. Subsequently, it was sent to the vacuum chamber of an evaporation deposition machine and evaporated. Using this substrate as the anode, other functional layers were sequentially deposited on it.

[0112] Hole injection layer: LiQ (10nm) is deposited on the substrate / anode surface as a hole injection layer at a deposition rate of 0.1nm / s.

[0113] Electron transport layer: Electron transport material is deposited on the surface of the hole injection layer as an electron transport layer, wherein the electron transport material includes the compounds prepared in the above embodiments and lithium 8-hydroxyquinoline (Liq), the doping mass ratio of Liq is 50%, and the deposition rate is 0.05 nm / s.

[0114] Electron injection layer: Yb (1 nm) was deposited on the surface of the electron transport layer as an electron injection layer at a deposition rate of 0.1 nm / s.

[0115] Cathode: Ag was deposited on the surface of the electron injection layer: 10wt% Mg (14nm) was used as the cathode, the deposition rate of Ag was 0.09nm / s, and the deposition rate of Mg was 0.01nm / s.

[0116] Table 9 shows the electron mobility of the electron transport layer corresponding to each electron transport material at a thickness of 60 nm. The electron mobility in Table 9 is expressed in scientific notation. In this embodiment of the invention, the value aE-b described in scientific notation is equivalent to a × 10⁻⁶. b For example, 1×10 5 It can be recorded as 1E-05.

[0117] As can be seen from the data in Table 9, all the compounds provided in the embodiments of the present invention have high glass transition temperatures (Tg), which is beneficial to improving the phase stability and high-temperature stability of the films made from them.

[0118] The compounds provided in the embodiments of the present invention have suitable HOMO and LUMO energy levels, which can reduce the carrier injection barrier, reduce device voltage and improve device efficiency.

[0119] The compounds provided in the embodiments of the present invention have high T1 energy levels. When used as n-type charge generating materials, they can ensure the energy transfer efficiency between the host and guest and suppress energy loss.

[0120] The compounds provided in the embodiments of the present invention also have high electron mobility, which helps to improve the voltage of OLED devices, especially the turn-on voltage and current efficiency.

[0121] Application Examples The following examples, Application Examples 1-9 and Comparative Examples 1-4, further illustrate the application effects of the compounds provided in Examples 1-32 in OLED devices. The OLED devices involved in Application Examples 1-9 and Comparative Examples 1-4 are manufactured using the same process, employing the same substrate and electrode materials, and maintaining consistent electrode film thickness. The difference lies in the different n-type doped layers of the different OLED devices.

[0122] All the above embodiments or comparative examples relate to tandem OLED devices (also known as stacked OLED devices), which contain two light-emitting units, including the following layers arranged in sequence: anode / substrate - hole injection layer - hole transport layer a - electron blocking layer a - light-emitting layer 1 - electron transport layer an-type doped layer - spacer layer - p-type doped layer - hole transport layer b - electron blocking layer b - light-emitting layer 2 - electron transport layer b - electron injection layer - cathode.

[0123] The fabrication method of the stacked OLED device is as follows: The transparent conductive ITO glass substrate (with an anode on its surface, purchased from China Southern Glass Group Co., Ltd.) was ultrasonically treated in a commercial cleaning agent, rinsed in deionized water, and then washed sequentially with ethanol, acetone and deionized water. It was baked in a clean environment until all moisture was removed, cleaned with ultraviolet photosynthetic ozone, and then treated with oxygen plasma for 30 seconds.

[0124] The glass substrate with the anode was placed in a vacuum chamber, and a vacuum was drawn. A 10 nm thick layer of HT:3wt% p-dopant was deposited on ITO as a hole injection layer at a deposition rate of 0.1 nm / s.

[0125] Compound HT was vapor-deposited on the surface of the hole injection layer to form a 14 nm thick hole transport layer a, with a deposition rate of 0.1 nm / s.

[0126] An electron blocking layer a (EB with a thickness of 10 nm) was deposited on the surface of hole transport layer a at a deposition rate of 0.1 nm / s.

[0127] BH:BD (20nm) was deposited on electron blocking layer a as light-emitting layer 1, wherein BH is the host light-emitting material and BD is doped with 2wt% fluorescent guest material, and the deposition rate is 0.1nm / s.

[0128] ET:Liq (50% by mass and 30 nm thick) was deposited on the surface of the light-emitting layer 1 as an electron transport layer a at a deposition rate of 0.1 nm / s.

[0129] An n-type charge transport material, Yb (99% by mass of n-type charge transport material, 1% by mass of Yb, and 10 nm in thickness), was deposited on electron transport layer a as an n-type doped layer at a deposition rate of 0.1 nm / s.

[0130] Ag (5 nm thick) was deposited as a spacer layer on the surface of the n-type doped layer at a deposition rate of 0.1 nm / s.

[0131] A p-type doped layer of HT: 5wt% p-dopant (10nm thick) was deposited on the spacer layer.

[0132] A 33 nm thick hole transport layer b was formed by evaporating HT on the surface of the p-type doped layer at a deposition rate of 0.1 nm / s.

[0133] An electron blocking layer b, EB (10 nm thick), was deposited on the surface of hole transport layer b at a deposition rate of 0.1 nm / s.

[0134] BH:BD (20 nm thick) was deposited on the surface of electron blocking layer b as light-emitting layer 2, where BH is the host light-emitting material and BD is doped with 2 wt% fluorescent guest material. The deposition rate was 0.1 nm / s.

[0135] On the surface of the light-emitting layer 2, ET:Liq (both mass percentages are 50% and the thickness is 35nm) is used as the electron transport layer b, and the evaporation rate is 0.1nm / s.

[0136] Yb (1 nm thick) was deposited on the surface of electron transport layer b as an electron injection layer at a deposition rate of 0.1 nm / s.

[0137] Ag:Mg (mass ratio 9:1, thickness 140nm) was vapor-deposited on the surface of the electron injection layer as a cathode.

[0138] The raw material compounds involved in the fabrication process of the above-mentioned stacked OLED devices are shown below:

[0139]

[0140]

[0141]

[0142]

[0143]

[0144]

[0145] In this context, the n-type charge transport materials used in the n-type doped layers of Application Examples 1-9 correspond one-to-one with the compounds provided in Examples 1-9. That is, the n-type charge transport material used in Application Example 1 is compound 1 provided in Example 1, the n-type charge transport material used in Application Example 2 is compound 3 provided in Example 2, the n-type charge transport material used in Application Example 3 is compound 6 provided in Example 3, and so on. The n-type charge transport material used in Application Example 9 is compound 267 provided in Example 9.

[0146] The n-type charge transport material used in the n-type doped layer of Comparative Example 1 is the CGL-1 material mentioned above; the n-type charge transport material used in the n-type doped layer of Comparative Example 2 is the CGL-2 material mentioned above; the n-type charge transport material used in the n-type doped layer of Comparative Example 3 is the CGL-3 material mentioned above; and the n-type charge transport material used in the n-type doped layer of Comparative Example 4 is the CGL-4 material mentioned above.

[0147] The performance of the stacked OLED devices provided in Application Examples 1-9 and Comparative Examples 1-4 was tested. During the test, a known driving circuit was used to connect the anode and cathode. The test items and results are shown below.

[0148] (1) Driving voltage, current efficiency, and color coordinates: Tested under a current density of 10 mA / cm², using IVL (current efficiency). Voltage Brightness testing system (Guangzhou Jinghe Instrument Co., Ltd.). The unit of driving voltage is V, and the unit of current efficiency is cd / A.

[0149] (2) Device lifetime at room temperature: The time it takes for the brightness of the device to decay to 95% of its initial brightness at a current density of 30 mA / cm² and at room temperature (LT95). The lifetime testing system is the M6400 OLED device lifetime tester from MCSCIENCE, South Korea. The unit of device lifetime is Hr.

[0150] (3) High-temperature lifespan of the device (also known as 85°C lifespan): The time it takes for the brightness of the device to decay to 95% of its initial brightness when the current density is 20mA / cm² and the temperature is 85°C. The unit of high-temperature lifespan is Hr.

[0151] (4) Start-up voltage: The driving voltage when the brightness of the test device is 1 nit. The unit of start-up voltage is V.

[0152] (5) Power efficiency: Tested under a current density of 10mA / cm², where the unit of power efficiency is lm / W.

[0153] The relevant test data are shown in Table 10: Table 10

[0154] As shown in Table 10, compared with the comparative examples, the OLED device provided by the present invention has been improved in terms of device voltage, device efficiency, and device lifespan. In particular, the high-temperature lifespan of the device has been significantly improved, which is more beneficial to improving the cycle stability of the device.

[0155] In addition, to compare the efficiency degradation of different OLED devices under high current density, an efficiency degradation coefficient for each device was defined. , , This is expressed as the device's maximum current efficiency. This indicates a drive current of 50mA / cm. 2 At that time, the current efficiency of the device. The larger the value, the more severe the efficiency roll-off of the device; conversely, the smaller the value, the better the problem of rapid degradation of the device under high current density has been controlled.

[0156] The efficiency degradation coefficients of the stacked OLED devices provided in Application Examples 1-9 and Comparative Examples 1-4 The values ​​are listed in Table 11 below.

[0157]

[0158] As shown in Table 11, the OLED devices prepared using the compounds provided in the embodiments of the present invention have smaller efficiency degradation coefficients (compared to Comparative Examples 1-4), which indicates that the efficiency roll-off problem of the OLED devices provided in the embodiments of the present invention is effectively controlled at high current densities.

[0159] In summary, OLED devices fabricated using the compounds provided in the embodiments of this invention exhibit numerous superior properties, including at least: lower operating voltage, higher current efficiency and power efficiency, and longer lifespan. These performance improvements are attributed to the compounds' high glass transition temperature, suitable HOMO and LUMO energy levels, high T1 energy level, and high electron mobility.

[0160] It has also been confirmed that the compounds provided in the embodiments of the present invention are particularly suitable for tandem blue light materials and can significantly improve the overall performance of blue OLED devices.

[0161] The above description is merely for the purpose of enabling those skilled in the art to understand the technical solutions of the present invention, and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A compound, characterized in that, The chemical structural formula of the compound is shown below: Where A represents O, S, and CR1R2; Ar1-Ar3 are each independently selected from one of hydrogen, protium, deuterium, tritium, substituted or unsubstituted C1-C18 alkyl, substituted or unsubstituted C6-C30 aryl, or substituted or unsubstituted C3-C30 heteroaryl. R, R1, and R2 are each independently selected from one of hydrogen, protium, deuterium, tritium, substituted or unsubstituted C1-C18 alkyl, substituted or unsubstituted C6-C30 aryl, or substituted or unsubstituted C3-C30 heteroaryl. n represents an integer from 0 to 7.

2. The compound according to claim 1, characterized in that, R is hydrogen, deuterium, substituted or unsubstituted C1-C8 alkyl, or substituted or unsubstituted C6-C10 aryl.

3. The compound according to claim 1, characterized in that, Ar1-Ar3 are each independently selected from one of hydrogen, protium, deuterium, tritium, substituted or unsubstituted C1-C8 alkyl, substituted or unsubstituted C6-C10 aryl, substituted or unsubstituted C3-C10 heteroaryl, and the heteroatom in the heteroaryl is an N atom or an S atom.

4. The compound according to claim 3, characterized in that, Ar1-Ar3 are all substituted or unsubstituted C6-C10 aryl groups; or, Two of Ar1-Ar3 are substituted or unsubstituted C6-C10 aryl groups, and the other is a substituted or unsubstituted C3-C10 heteroaryl group; or, Two of Ar1-Ar3 are hydrogen, protium, deuterium or tritium, and the other is a substituted or unsubstituted C6-C10 aryl or a substituted or unsubstituted C3-C10 heteroaryl.

5. The compound according to any one of claims 1-3, characterized in that, When the aryl or heteroaryl group includes a substituent, the substituent includes at least one of methyl, propyl, butyl, or nitrile.

6. A charge transport material, characterized in that, The charge transport material includes the compound according to any one of claims 1-5.

7. The use of the compound according to any one of claims 1-5 in organic electroluminescent devices, organic solar cells, organic thin-film transistors, organic photodetectors, organic field-effect transistors, organic integrated circuits or organic photoreceptors.

8. An organic electroluminescent device, characterized in that, The organic electroluminescent device includes: a first electrode, a second electrode, and a light-emitting unit disposed between the first electrode and the second electrode; The light-emitting unit includes at least an electron transport layer, and the electron transport layer includes the charge transport material as described in claim 6.

9. An organic electroluminescent device, characterized in that, The organic electroluminescent device includes: a first electrode, a second electrode, and a plurality of light-emitting units disposed between the first electrode and the second electrode; A charge generation layer is provided between any two adjacent light-emitting units, the charge generation layer comprising an n-type doped layer, the n-type doped layer comprising the charge transport material as described in claim 6.

10. The organic electroluminescent device according to claim 9, characterized in that, The n-type doped layer further includes a dopant, which is at least one of alkali metal, alkaline earth metal and rare earth metal, and the mass percentage of the dopant in the n-type doped layer is 0.5%-50%.

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