Stereoselective nitrocarbazole oxime ester compound, and preparation method therefor and use thereof

Abstract

The present invention provides a stereoselective nitrocarbazole oxime ester compound, a preparation method therefor and a use thereof. The stereoselective nitrocarbazole oxime ester compound has a structure as shown in formula I. In formula I, the symbol E represents that the O-N bond in the oxime group has a trans orientation and is on the opposite side to the carbonyl group; and R1 is selected from C6-C16 alkyl groups. The compound of the present invention has significantly high sensitivity in a photocurable composition formulation, especially a high-sensitivity photoresist formulation, whereas a cis isomer of the compound has very low sensitivity.

Description

A stereoselective nitrocarbazole oxime compound, its preparation method and application

[0001] Cross-references to related applications

[0002] This application claims priority to Chinese patent application No. CN202510331676.7, filed on March 19, 2025, the entire contents of which are incorporated herein by reference. Technical Field

[0003] This invention relates to a stereoselective nitrocarbazole oxime compound, its preparation method, and its applications. Background Technology

[0004] Photoinitiators, also known as photosensitizers or photocuring agents, are compounds that absorb energy of a certain wavelength in the ultraviolet (250–420 nm) or visible (400–800 nm) region, generating free radicals, cations, etc., thereby initiating monomer polymerization, cross-linking, and curing. Currently, photoinitiators generally have low photosensitivity and are subject to significant limitations in the types of light sources they can be used with; the vast majority are only suitable for short-wavelength ultraviolet excitation.

[0005] Oxime esters are widely used in high-end photoresists and inks such as black matrices, LDI photoresist inks, pillar spacers, organic insulating films, and photoresists due to their high photosensitivity. However, industry professionals are constantly searching for oxime ester compounds with better performance to improve the performance of photoresists, especially high-sensitivity oxime ester compounds with good solubility and long-wavelength absorption capabilities. Summary of the Invention

[0006] To address the aforementioned technical problems, this invention provides a stereoselective nitrocarbazole oxime compound, its preparation method, and its applications.

[0007] In a first aspect, the present invention provides a stereoselective nitrocarbazole oxime compound having a structure as shown in Formula I.

[0008] In Formula I, the symbol E indicates that the ON bond distribution in the oxime group is trans, and it is on the opposite side of the carbonyl group;

[0009] R1 is selected from C6-C16 alkyl groups.

[0010] The stereoselective nitrocarbazole oxime ester compound of this invention has a trans structure, and its exposure sensitivity is significantly higher than that of the corresponding cis isomer compound. Furthermore, compared to short-side-chain compounds (i.e., R1 is C1-C5 alkyl) or cycloalkyl-substituted side-chain compounds (i.e., R1 is cycloalkyl), the stereoselective nitrocarbazole oxime ester compound of this invention exhibits better solubility in the solvent propylene glycol methyl ether acetate, making it more suitable for industrial use.

[0011] According to some embodiments of the stereoselective nitrocarbazole oxime ester compounds of the present invention, R1 in Formula I is selected from C6-C10 straight-chain alkyl groups, such as n-hexyl, n-heptyl, n-octyl, n-nonyl, and n-decyl. The compounds obtained by the present invention exhibit better solubility in the solvent propylene glycol methyl ether acetate and are more suitable for industrial use.

[0012] According to some embodiments of the highly sensitive oxime ester compounds of the present invention, the compounds are selected from:

[0013] A second aspect of the present invention provides a method for preparing the stereoselective nitrocarbazole oxime compound described in the first aspect of the present invention, comprising the following steps:

[0014] Step (1): The raw material M1 is subjected to Friedel-Crafts acylation reaction with R1CH2COCl to obtain intermediate M2;

[0015] Step (2): React intermediate M2 with nitric acid to obtain intermediate M3;

[0016] Step (3): React intermediate M3 with nitrite or nitrous acid under acidic conditions to obtain a mixture of trans isomer M4 and cis isomer M4'.

[0017] Step (4): Purify the product obtained in step (3) to obtain pure trans isomer M4;

[0018] Step (5): The trans isomer M4 is subjected to esterification reaction with CH3COCl or (CH3CO)2O, and further purified to obtain the compound described in Formula I;

[0019] In M4 and Formula I, the symbol E indicates that the ON bond distribution in the oxime group is trans, opposite to the carbonyl group; in M4', Z indicates that the ON bond distribution in the oxime group is cis, on the same side as the carbonyl group.

[0020] R1 is selected from C6-C16 alkyl groups.

[0021] In some embodiments of the preparation method described in this invention, R1 is selected from C6-C10 straight-chain alkyl groups, such as n-hexyl, n-heptyl, n-octyl, n-nonyl, and n-decyl.

[0022] According to some embodiments of the preparation method of the present invention, in step (1), the Friedel-Crafts acylation reaction is carried out in a chlorinated hydrocarbon solvent in the presence of a catalyst.

[0023] According to some embodiments of the preparation method described in this invention, the molar ratio of raw material M1 to R1CH2COCl is 1:(1-1.1); for example: 1:1, 1:1.02, 1:1.05, 1:0.07, 1:1.1 or any value between them.

[0024] According to some embodiments of the preparation method of the present invention, the chlorinated hydrocarbon solvent is selected from one or more of 1,2-dichloroethane, dichloromethane, or o-dichlorobenzene.

[0025] According to some embodiments of the preparation method described in this invention, the catalyst comprises aluminum trichloride.

[0026] According to some embodiments of the preparation method described in this invention, the molar ratio of the catalyst to the R1CH2COCl is 1:1.

[0027] According to some embodiments of the preparation method of the present invention, in step (1), the temperature of the Friedel-Crafts acylation reaction is -15 to 25°C; for example, -15°C, -10°C, 0°C, 10°C, 20°C, 25°C or any value between them.

[0028] According to some embodiments of the preparation method of the present invention, in step (1), the temperature of the Friedel-Crafts acylation reaction is -10 to 10°C.

[0029] According to some embodiments of the preparation method described in this invention, the molar ratio of raw material M3 to nitrite or nitrous acid in step (3) is 1:(1-1.5); for example, it is 1:1, 1:1.1, 1:1.2, 1:1.3, 1:1.4, 1:1.5 or any value between them.

[0030] According to some embodiments of the preparation method of the present invention, the nitrite is selected from one or more of isoamyl nitrite, butyl nitrite, sec-butyl nitrite, isobutyl nitrite, tert-butyl nitrite, isopropyl nitrite or propyl nitrite, ethyl nitrite or methyl nitrite.

[0031] According to some embodiments of the preparation method described in this invention, the reaction is carried out in an organic solvent.

[0032] According to some embodiments of the preparation method of the present invention, the organic solvent is selected from one or more of DMSO, alcohol solvents, ether solvents, ester solvents, aromatic solvents or chlorinated alkane solvents.

[0033] According to some embodiments of the preparation method of the present invention, the alcohol solvent is selected from one or more of methanol, ethanol, isopropanol, propanol and 2,2,3,3-tetrafluoropropanol.

[0034] According to some embodiments of the preparation method of the present invention, the ether solvent is selected from one or more of diethyl ether, tetrahydrofuran, methyltetrahydrofuran, methyl tert-butyl ether, diisopropyl ether, 1,4-dioxane, ethylene glycol dimethyl ether, ethylene glycol diethyl ether, diethylene glycol dimethyl ether, and polyethylene glycol dimethyl ether.

[0035] According to some embodiments of the preparation method of the present invention, the ester solvent is selected from one or more of ethyl acetate, butyl acetate, sec-butyl acetate, ethyl butyrate, ethylene glycol methyl ether acetate, and propylene glycol methyl ether acetate.

[0036] According to some embodiments of the preparation method of the present invention, the aromatic solvent is selected from one or more of benzene, toluene, and chlorobenzene.

[0037] According to some embodiments of the preparation method of the present invention, the chloroalkane is selected from one or more of dichloromethane, 1,2-dichloroethane, chlorobenzene and fluorobenzene.

[0038] According to some embodiments of the preparation method described in this invention, the reaction temperature is 0-35°C; for example, 0°C, 5°C, 10°C, 20°C, 25°C, 30°C, 35°C.

[0039] According to some embodiments of the preparation method of the present invention, in step (4), the mixture of intermediates M4 and M4' obtained in step (3) is recrystallized in an organic solvent to obtain high-purity intermediate M4.

[0040] In some embodiments of the preparation method according to the present invention, the organic solvent is an alcohol, such as ethanol and / or methanol.

[0041] According to some embodiments of the preparation method of the present invention, in step (4), the mixture of intermediates M4 and M4' obtained in step (3) is separated and purified by silica gel column chromatography to obtain high-purity intermediate M4.

[0042] According to some embodiments of the preparation method of the present invention, in step (5), the molar ratio of the high-purity intermediate M4 obtained in step (4) to CH3COCl or (CH3CO)2O is 1:(1-1.5); for example, it is 1:1, 1:1.1, 1:1.2, 1:1.3, 1:1.4, 1:1.5 or any value between them.

[0043] According to some embodiments of the preparation method described in this invention, the esterification reaction is carried out in an aprotic solvent.

[0044] According to some embodiments of the preparation method of the present invention, the aprotic solvent is selected from one or more of dichloromethane, ethyl acetate, toluene, and methyl tert-butyl ether.

[0045] According to some embodiments of the preparation method of the present invention, when the reaction raw material is CH3COCl, that is, when M4 reacts with CH3COCl, an acid-binding agent needs to be added to the reaction system.

[0046] In some embodiments of the preparation method described in this invention, the acid-binding agent is selected from pyridine and / or triethylamine.

[0047] According to some embodiments of the preparation method of the present invention, the molar ratio of the acid-binding agent to the CH3COCl is (1-1.2):1; for example, 1:1, 1.1:1, 1.2:1 or any value between them.

[0048] According to some embodiments of the preparation method of the present invention, the temperature of the esterification reaction is 20-60°C, for example 20°C, 30°C, 35°C, 40°C, 50°C, 60°C or any value between them.

[0049] According to some embodiments of the preparation method of the present invention, the esterification reaction time is 3-20 h; for example, 3 h, 4 h, 5 h, 6 h, 7 h, 8 h, 9 h, 10 h, 15 h, 20 h or any value between them.

[0050] A third aspect of the present invention provides a photocurable composition comprising a photoinitiator and a free radical polymerizable compound, wherein the photoinitiator comprises a stereoselective nitrocarbazole oxime ester compound as described in the first aspect of the present invention or a stereoselective nitrocarbazole oxime ester compound obtained by the preparation method described in the second aspect of the present invention.

[0051] According to some embodiments of the photocurable composition of the present invention, the free radical polymerizable compound is selected from acrylate compounds, methacrylate compounds, and combinations thereof.

[0052] According to some embodiments of the photocurable composition of the present invention, the free radical polymerizable compound is selected from one or more of alkyl acrylates, cycloalkyl acrylates, hydroxyalkyl acrylates, dialkylaminoalkyl acrylates, alkyl methacrylates, cycloalkyl methacrylates, hydroxyalkyl methacrylates, dialkylaminoalkyl methacrylates, acrylic epoxy resins, acrylic polyester resins, unsaturated polyester resins, acrylic polyether resins, and acrylic polyurethane resins.

[0053] According to some embodiments of the photocurable composition of the present invention, the free radical polymerizable compound includes one or more of methyl acrylate, butyl acrylate, cyclohexyl acrylate, 2-hydroxyethyl acrylate, isobornyl acrylate, ethyl methacrylate, polysiloxane acrylate, diacrylate of vinyl acetate, diacrylate of styrene, diacrylate of ethylene glycol, diacrylate of polyethylene glycol, diacrylate of propylene glycol, diacrylate of neopentyl glycol, diacrylate of 1,6-hexanediol, trihydroxymethane triacrylate, pentaerythritol tetraacrylate, dipentaerythritol hexaacrylate, vinyl acrylate, and triallyl isocyanurate.

[0054] According to some embodiments of the photocurable composition of the present invention, the stereoselective nitrocarbazole oxime compound in the photocurable composition accounts for 0.1-4.0% by mass, for example 0.5%, 1%, 1.5%, 2%, 2.5%, 3%, 3.5%, 4% or any value between them.

[0055] According to some embodiments of the photocurable composition of the present invention, the photocurable composition of the present invention may also include other photoinitiators or co-initiators. The present invention does not specifically limit the specific types of the other initiators or co-initiators, and any photoinitiator or co-initiator that is helpful to the photocuring performance can be selected.

[0056] In a fourth aspect, the present invention provides a photoresist, wherein the raw materials for preparing the photoresist include a photoinitiator, a multifunctional acrylate monomer, an alkali-soluble resin, and an organic solvent, wherein the photoinitiator includes a stereoselective nitrocarbazole oxime ester compound as described in the first aspect of the present invention or a stereoselective nitrocarbazole oxime ester compound obtained by the preparation method described in the second aspect of the present invention.

[0057] According to some embodiments of the photoresist of the present invention, the multifunctional acrylate monomer is selected from acrylate monomers with a functionality ≥3. The present invention does not specifically limit the type of the multifunctional acrylate monomer, and those skilled in the art can select from conventional multifunctional acrylate monomers.

[0058] According to some embodiments of the photoresist of the present invention, the multifunctional acrylate monomer includes dipentaerythritol hexaacrylate and / or pentaerythritol acrylate.

[0059] According to some embodiments of the photoresist of the present invention, the alkali-soluble resin is a resin having acidic groups, which can be dissolved or dispersed when exposed to an alkaline solution. The present invention does not specifically limit the type of alkali-soluble resin, and those skilled in the art can select from conventional alkali-soluble resins.

[0060] According to some embodiments of the photoresist of the present invention, the alkali-soluble resin includes polyacrylate or methacrylate having carboxylic acid groups.

[0061] According to some embodiments of the photoresist of the present invention, the alkali-soluble resin includes one or more of methacrylic acid, itaconic acid, and maleic acid, and one or more of methyl acrylate, methyl methacrylate, butyl methacrylate, benzyl acrylate, benzyl methacrylate, hydroxyethyl acrylate, styrene, butadiene, and maleic anhydride, such as methyl methacrylate and methacrylic acid copolymer, benzyl methacrylate and methacrylic acid copolymer, methyl methacrylate and butyl methacrylate, and methacrylic acid and styrene copolymer.

[0062] According to some embodiments of the photoresist of the present invention, the organic solvent is selected from one or more of ester solvents, aromatic solvents, and haloalkane solvents.

[0063] According to some embodiments of the photoresist of the present invention, the organic solvent is selected from one or more of propylene glycol monomethyl ether acetate, ethylene glycol monomethyl ether acetate, toluene, xylene, and tetrachloroethane.

[0064] According to some embodiments of the photoresist of the present invention, the photoinitiator further includes one or more of the following: 2,2-dimethoxy-2-phenylacetophenone, 2-dimethylamino-2-benzyl-1-(4-morpholinylphenyl)-1-butanone, 2-dimethylamino-2-(4-methylbenzyl)-1-(4-morpholinylphenyl)-1-butanone, 2-dimethylamino-2-benzyl-1-(4-piperidinylphenyl)-1-butanone, 2,4,6-trimethylbenzoylbenzene-diphenylphosphine oxide, bis(2,4,6-trimethylbenzoyl)-phenylphosphine oxide, 2-isopropylthioxanthonone, 2,4-diethylthioxanthonone, and bis(2,6-difluoro-3-pyrrolephenyl)dicenoctanetane.

[0065] According to some embodiments of the photoresist of the present invention, the photoinitiator further includes commercially available oxime ester photoinitiators, such as OXE01, OXE02, OXE03, OXE04, PBG305, PBG304, PBG3057, NCI1919, NCI831, etc.

[0066] According to some embodiments of the photoresist of the present invention, the raw materials for preparing the photoresist further contain pigments.

[0067] According to some embodiments of the photoresist of the present invention, the pigment is one or more of red pigment, green pigment, blue pigment or black pigment.

[0068] According to some embodiments of the photoresist of the present invention, the red pigment includes CI Pigment Red 177.

[0069] According to some embodiments of the photoresist of the present invention, the green pigment includes CI Pigment Green 7.

[0070] According to some embodiments of the photoresist of the present invention, the blue pigment includes CI Pigment Blue 15:6 and Solvent Blue 25.

[0071] According to some embodiments of the photoresist of the present invention, the black pigment includes carbon black, titanium black, and CI pigment black 1.

[0072] According to some embodiments of the photoresist of the present invention, the pigment in the photoresist is a black pigment.

[0073] According to some embodiments of the photoresist of the present invention, the pigments in the photoresist are carbon black and titanium black.

[0074] According to some embodiments of the photoresist of the present invention, the raw materials for preparing the photoresist further include heat stabilizers and / or light stabilizers, such as p-methoxyphenol. Other resins may also be added, such as polyalkyl methacrylate, ethyl cellulose, carboxymethyl cellulose, linear phenolic resin, polyvinyl butyral, polyvinyl acetate, polyester, polyimide, etc.

[0075] Using the photoresist of this invention as raw material, and through existing technology processes such as multiple coatings, exposures, and developments of different colored photoresists, a color filter device with excellent optical performance can be obtained. This device is an important component of a color display screen, in which the color units exhibit pure color and high light transmittance, while the colorless parts exhibit low yellowing and high light transmittance.

[0076] Photoresist is typically applied using a spin-coating method to evenly distribute it onto a substrate. After drying at 80-90°C, volatile components such as solvents are separated, leaving a solid film. A mask is placed on top of this film, and the substrate is exposed to appropriate exposure levels under a 365nm mercury lamp or LED light source. The exposed material is then developed in an alkaline solution such as sodium carbonate or sodium hydroxide to remove unexposed portions of the film, leaving the exposed image. Following this, a cleaning and post-baking process at 200-230°C is performed to ensure better adhesion of the image to the substrate. By following the designed procedure and fabricating different colors and patterns, or by combining this with necessary protective film processing, the optical filter device is obtained.

[0077] In a fifth aspect, the present invention provides a black matrix prepared from a photoresist comprising the photoresist described in the fourth aspect of the present invention, wherein the pigment in the photoresist is a black pigment, preferably carbon black and titanium black.

[0078] In a sixth aspect, the present invention provides a color filter device prepared from a photoresist comprising the photoresist described in the fourth aspect of the present invention, wherein the pigment in the photoresist is a red pigment, a green pigment, or a blue pigment.

[0079] In a seventh aspect, the present invention provides a display obtained by photocuring a stereoselective nitrocarbazole oxime ester compound as described in the first aspect of the present invention or a stereoselective nitrocarbazole oxime ester compound obtained by the preparation method described in the second aspect of the present invention as a photoinitiator.

[0080] According to some embodiments of the display of the present invention, the display includes a PCB display, an LCD display, and an OLED display. Using the compound of Formula I or a photoinitiator composition containing Formula I and a photoresist containing Formula I as raw materials, color filters, LCD color displays, OLED color displays, PCBs, and printed materials can be obtained through necessary processing steps.

[0081] The eighth aspect of the present invention provides the use of the stereoselective nitrocarbazole oxime ester compound described in the first aspect of the present invention, the stereoselective nitrocarbazole oxime ester compound obtained by the preparation method of the second aspect of the present invention, the photocurable composition described in the third aspect of the present invention, or the photoresist described in the fourth aspect of the present invention in the preparation of colored or uncolored inks, coatings, adhesives, filters, displays, pattern printing, printing plates, 3D printing, PCB photoresist, PCB solder resist ink, substrate protective coating, electronic device protective coating, passivation film, liquid or dry film resist material, sealant, dental material, optical material, optical film, optical fiber coating, insulating film, polarizer, microscope lens, and recording material.

[0082] A ninth aspect of the present invention also provides an adhesive comprising the photocurable composition described in the third aspect of the present invention.

[0083] According to some embodiments of the adhesive described in this invention, other necessary components may be added according to the performance requirements of the adhesive.

[0084] According to some embodiments of the adhesive of the present invention, the adhesive further includes one or more of a polymer, a stabilizer, a surfactant, a leveling agent, and a dispersant.

[0085] According to some embodiments of the adhesive of the present invention, the polymer has a weight-average molecular weight of 5,000-100,000. For example, polymers with a weight-average molecular weight of 5,000-100,000 are used to improve adhesive properties for bonding glass, plastics, metal components, etc.

[0086] In addition, those skilled in the art can easily add other necessary components, such as stabilizers, surfactants, leveling agents, and dispersants, depending on the existing technology and the intended use of the photocurable composition.

[0087] The tenth aspect of the present invention also provides an optical spacer prepared from a photoresist comprising the photoresist described in the fourth aspect of the present invention, wherein the pigment in the photoresist is a black pigment, preferably carbon black and titanium black.

[0088] The eleventh aspect of the present invention also provides a printed article, which is obtained by photocuring using a stereoselective nitrocarbazole oxime ester compound as described in the first aspect of the present invention or a stereoselective nitrocarbazole oxime ester compound obtained by the preparation method described in the second aspect of the present invention as a photoinitiator.

[0089] According to some embodiments of the printed article of the present invention, the printed article includes a printed circuit board and a color filter.

[0090] The beneficial effects of the present invention include: the stereoselective nitrocarbazole oxime ester compound of the present invention has good solubility and high sensitivity. It is easy to formulate in photocurable composition formulations, especially photoresists, and there is no risk of precipitation at low temperature storage. It can significantly improve the crosslinking density of the cured film surface, thereby significantly improving the surface impedance value. Detailed Implementation

[0091] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to embodiments. The specific embodiments described herein are for illustrative purposes only and are not intended to limit the invention in any way. Furthermore, descriptions of well-known structures and techniques are omitted in the following description to avoid unnecessarily obscuring the concepts of this disclosure. Such structures and techniques have also been described in many publications.

[0092] Experimental materials and equipment:

[0093] Light source equipment:

[0094] 365nm LED surface light source, Shanghai Futanxi Technology Co., Ltd.

[0095] Test equipment:

[0096] Differential scanning calorimeter: HSC-1, Beijing Hengjiu Experimental Equipment Co., Ltd.;

[0097] Stereo microscope: HY-950S, Beijing Huanyu Technology Co., Ltd., linewidth unit is μm;

[0098] Yellowness meter: SC-80C fully automatic colorimeter, Beijing Jingyi Kangguang Optical Instrument Co., Ltd.;

[0099] Constant temperature water bath: QW-FAD-WBTC, Hangzhou Qiwei Instrument Co., Ltd.

[0100] Experimental materials:

[0101] Genomer 4212: Aliphatic polyurethane acrylate, a product of RAHN Corporation;

[0102] DPHA: Dipentaerythritol hexaacrylate, a product of Tianjin Tianjiao Chemical Co., Ltd.

[0103] HDDA: 1,6-hexanediol diacrylate, a product of Tianjin Tianjiao Chemical Co., Ltd.

[0104] Comparative compound C-1: Example 1 of preparation of the comparative compound;

[0105] Comparative compound C-2: Example 2 of preparation of the comparative compound;

[0106] Comparative compound C-3: Comparative compound preparation example 3;

[0107] Comparative compound C-4: Example 4 of the preparation of the comparative compound;

[0108] Comparative compound C-5: Example 5 of the preparation of the comparative compound.

[0109] Note: Z in C-1 indicates that the ON bond in the oxime ester group is in the cis double bond configuration, and is on the same side as the carbonyl group on the double bond.

[0110] Solubility test method:

[0111] Weigh 10g of analytical grade propylene glycol methyl ether acetate into a 20ml round-mouth bottle. Add a stir bar, adding 0.100g of sample at a time. Turn on the electromagnetic stirrer and maintain the temperature in a constant temperature oven at 23℃. Dissolve until clear within 30 minutes; otherwise, it is considered completely dissolved. Calculate the percentage solubility.

[0112] Solubility is an essential property of any solution formulation component. Due to the requirements of the formulation process, the photoinitiator needs to have a solubility of more than 4% in propylene glycol methyl ether acetate at 23°C to meet the usage requirements. The formulated photoresist product needs to be stored in a low-temperature environment of 2-8°C. If it does not have sufficient solubility, precipitation may occur, which will cause the product to be scrapped or affect its use, resulting in a decrease in yield and becoming a quality accident. Therefore, the photoinitiator component must be examined for its good solubility, and a compound with a solubility of 4% or more is considered to have good solubility.

[0113] Compound preparation

[0114] Preparation Example 1: 6-Nitro-3-(2E-2-acetoxyiminooctanoyl)-9-(2-ethylhexyl)carbazole

[0115] Step 1a. In a 250 mL three-necked flask, add 6 g (0.0215 mol) of 9-(2-ethylhexyl)carbazole and 50 mL of dichloromethane, stir to dissolve, weigh 2.87 g (0.0215 mol) of anhydrous aluminum trichloride, add to the reaction flask, stir and cool to 0 °C, add 3.5 g (0.0215 mol) of n-octanoyl chloride dropwise, stir and react for 4 h after the addition is complete; acidify the reaction solution with hydrochloric acid and water, wash with water, remove dichloromethane, and obtain 8.75 g of light yellow oily substance, with HPLC purity of 98.5%, which is intermediate I-1A, with a yield of 100%;

[0116] Step 1b. In a 100 mL three-necked flask, add 8.11 g (0.02 mol) of intermediate I-1A obtained in step 1a, dissolve in 40 mL of dichloromethane, maintain the solution at 30 °C, add 1.94 g (0.02 mol) of concentrated nitric acid dropwise, stir the reaction for 8 h, wash the reaction solution with water, evaporate the dichloromethane to dryness, add 10 mL of ethyl acetate and 35 mL of methanol to the residue, heat until the solution is clear, begin to cool and crystallize, keep at 0 °C for 1 h, filter the precipitated crystals, dry under reduced pressure to obtain 7.8 g of light yellow solid powder intermediate I-1B, yield 86.5%, HPLC purity 98.2%; DSC melting point 89.7 °C;

[0117] Step 1c. In a 50 mL three-necked flask, 3.0 g (6.7 mmol) of intermediate I-1B obtained in step 1b and 30 mL of ethyl acetate were added and dissolved. 0.82 g (8 mmol) of butyl nitrite was weighed, and 0.7 g of concentrated hydrochloric acid was added dropwise. The mixture was stirred at 25 °C for 5 h. 30 mL of water was added, and the aqueous layer was separated to obtain a yellow ethyl acetate solution. The solution was washed once with 30 mL of water. HPLC analysis showed that the solution contained 88.2% of the major isomer and 6.3% of the minor isomers. Ethyl acetate was removed by vacuum distillation, and 30 mL of methanol was added while hot. The mixture was cooled to precipitate a yellow solid. The temperature was then lowered to -15 °C, and the mixture was filtered to obtain 2.4 g of yellow solid powder intermediate I-1C. After vacuum drying, the yield was 74.7%. HPLC analysis showed a purity of 98.51% and a melting point of 29.6 °C.

[0118] Step 1d. In a 50 mL three-necked flask, add 2.0 g (4.17 mmol) of intermediate I-1C obtained in step 1c and 15 mL of dichloromethane, and add 0.47 g (4.6 mmol) of acetic anhydride dropwise. Stir the reaction mixture at 35 °C for 5 h. Wash the reaction solution with water, remove the dichloromethane by vacuum distillation, add 2.5 mL of ethyl acetate and 7 mL of n-heptane while hot, and cool to precipitate a yellow solid. After drying, 1.86 g of the solid was obtained, with a yield of 85.7%. HPLC analysis showed a purity of 99.32%; DSC melting point was 99.8 °C. 1 H-NMR data confirm that it is the compound shown in Formula I-1; 1 H-NMR data (CDCl3, δ [ppm])

[0119] Preparation Examples 2-6 were conducted by replacing n-octanoyl chloride with different alkyl acyl chlorides, following the method of Preparation Example 1, to obtain the respective target compounds. The physical properties are shown in Table 1, and the 1H NMR data are shown in Table 2.

[0120] Comparative Compound Preparation Example 1: 6-Nitro-3-[2(Z)-2-acetoxyiminooctanoyl]-9-(2-ethylhexyl)carbazole

[0121] Step 7a. Following the procedure 1c of Preparation Example 1, toluene was used instead of ethyl acetate as the solvent. HPLC analysis of the reaction product showed that intermediate C-1C content was 40.51% and intermediate I-1C content was 46.82%. Separation was performed by silica gel column chromatography, with heptane-ethyl acetate (20:1) as the eluent to obtain the C-1C fraction. After evaporating the eluent of the minor fraction to remove the solvent, 1.0 g of a yellow viscous substance was obtained, with a yield of 31.1%. HPLC analysis showed that the purity of C-1C was 98.8%.

[0122] Step 7b. In a 50 mL three-necked flask, add 0.5 g (1.04 mmol) of intermediate C-1C obtained in step 7a and 5 mL of dichloromethane, and add 0.12 g (1.17 mmol) of acetic anhydride dropwise. Stir the reaction at 35 °C for 5 h. Wash the reaction solution with water, dry the organic phase solution with anhydrous sodium sulfate, filter, and remove most of the dichloromethane by vacuum distillation. Add 2 mL of methanol while hot, and cool to -10 °C. No solid precipitates. After removing the solvent under reduced pressure, a yellow viscous liquid is obtained. 0.5 g yield 92.2%, HPLC purity 98.70%. 1 H-NMR data confirm that it is the compound shown in formula C-1; 1 H-NMR data (CDCl3, δ [ppm]) are listed in Table 2.

[0123] Comparative compound preparation examples 2-5

[0124] Following the method of Preparation Example 1, different alkyl acyl chlorides were used instead of n-octanoyl chloride to complete the experiments of Preparation Examples 2-5 of Comparative Compounds, and the target compounds were obtained. The physical property data are shown in Table 1, and the nuclear magnetic resonance hydrogen spectrum data are shown in Table 2.

[0125] Table 1. Material property data of the preparation example

[0126] Table 2. 1H NMR Spectrum Data of Compounds from the Preparation Examples

[0127] Preparation of alkali-soluble resins

[0128] 20g of benzyl methacrylate, 3g of methacrylic acid, 7g of hydroxyethyl methacrylate, 1.4g of azobisisobutyronitrile, and 0.5g of dodecanethiol were dissolved in 200mL of toluene and placed in a constant-pressure dropping funnel. 100mL of toluene was added to a 500mL four-necked flask, purged with nitrogen, and the temperature was raised to 80℃. The solution from the funnel was added dropwise, and after reacting for 6 hours, the mixture was cooled, filtered, and dried to obtain 24g of a white alkali-soluble resin.

[0129] Preparation of black pigment

[0130] Take 50g of the alkali-soluble resin prepared by the above method, 50g of Mitsubishi PK7 carbon black, 100g of DPHA, and 250g of propylene glycol methyl ether acetate (PGMEA) and put them into a 500mL beaker. Mix them for 15 minutes at 5000r / min using a high-speed shear mixer to obtain a black color paste.

[0131] Examples and Comparative Examples of Photoresist Compositions

[0132] The compounds prepared in Preparation Examples 1-6, Comparative Compound C-1, Comparative Compound C-2, Comparative Compound C-3, Comparative Compound C-4, and Comparative Compound C-5 were used as photoinitiators. They were mixed and heated to dissolve in propylene glycol methyl ether acetate (PGMEA) according to the proportions in Table 3, and then mixed with black pigment according to the proportions in Table 3. The amount is measured in grams.

[0133] After thoroughly mixing all components, a scraper test was immediately performed. No particles larger than 1 μm were found in any of the formulations. All formulations were then sealed and stored in a 5°C refrigerator for 4 weeks. Upon removal, a scraper test was performed again. No particles larger than 1 μm were found in Examples 1-6 and Comparative Example 1, while Comparative Examples 2, 3, 4, and 5 showed significant particles larger than 1 μm. This indicates that the formulations in Comparative Examples 2, 3, 4, and 5 are unstable under low-temperature storage conditions. Compounds C-2, C-3, C-4, and C-5 pose a risk of precipitation under low-temperature conditions and are not feasible for formulation application.

[0134] Examples 1-6 and Comparative Example 1 were coated onto glass slides using 10 μm wire rods, dried in a 90°C oven for 5 min, developed using a 365 nm surface light source and a 41-step exposure scale as a mask, and then rinsed with 0.0425% KOH aqueous solution at 25°C after curing. The films were then soaked in purified water for 10 s and dried in a 90°C oven for 30 min. The film retention order was observed and recorded as a sensitivity evaluation standard. A higher film retention order after curing indicates higher formulation sensitivity and better photoinitiator sensitivity performance. The corresponding values ​​are recorded in Table 3.

[0135] Table 3

[0136] The stereoselective nitrocarbazole oxime ester group of this invention has a trans structure, and it was unexpectedly found that its exposure sensitivity is significantly higher than that of the corresponding cis isomer compound C-1. Simultaneously, it exhibits good solubility in the solvent propylene glycol methyl ether acetate, making it suitable for industrial use. It was also unexpectedly found that compounds with shorter side chains, such as C-2, C-3, and C-4, and compounds with cyclic alkyl-substituted side chains, such as C-5, have solubility too low for industrial use.

[0137] In summary, the compounds of this invention exhibit good solubility in photoresist formulations. When used in the same amount as comparative compound C-1, the compounds of this invention exhibit significantly higher sensitivity. Comparative compound C-1 is a cis isomer of compound I-1 of this invention, indicating that the trans isomer of this invention has significantly higher sensitivity than its corresponding cis isomer.

[0138] 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 stereoselective nitrocarbazole oxime ester compound having the structure shown in Formula I, In Formula I, the symbol E indicates that the ON bond distribution in the oxime group is trans, and it is on the opposite side of the carbonyl group; R1 is selected from C6-C16 alkyl groups.

2. The stereoselective nitrocarbazole oxime compound according to claim 1, characterized in that, R1 is selected from C6-C10 straight-chain alkyl groups.

3. The stereoselective nitrocarbazole oxime compound according to claim 1 is specifically selected from:

4. A method for preparing the stereoselective nitrocarbazole oxime compound according to any one of claims 1-3, comprising the following steps: Step (1): The raw material M1 is subjected to Friedel-Crafts acylation reaction with R1CH2COCl to obtain intermediate M2; Step (2): React intermediate M2 with nitric acid to obtain intermediate M3; Step (3): Intermediate M3 is reacted with nitrite or nitrous acid under acidic conditions to obtain trans isomer M4 and cis isomer M. 4， A mixture; Step (4): Purify the product obtained in step (3) to obtain pure trans isomer M4; Step (5): The trans isomer M4 is subjected to esterification reaction with CH3COCl or (CH3CO)2O, and further purified to obtain the compound described in Formula I; In M4 and Formula I, the symbol E indicates that the ON bond distribution in the oxime group is trans, opposite to the carbonyl group; in M4 ’ In the middle Z, it indicates that the ON bond distribution in the oxime group is cis, and it is on the same side as the carbonyl group; R1 is selected from C6-C16 alkyl groups, preferably C6-C10 straight-chain alkyl groups.

5. The preparation method according to claim 4, characterized in that, In step (1), the Friedel-Crafts acylation reaction is carried out in a chlorinated hydrocarbon solvent in the presence of a catalyst. Preferably, the molar ratio of raw material M1 to R1CH2COCl is 1:(1-1.1); Preferably, the chlorinated hydrocarbon solvent is selected from one or more of 1,2-dichloroethane, dichloromethane, or o-dichlorobenzene; Preferably, the catalyst comprises aluminum trichloride; And / or, in step (3), the molar ratio of raw material M3 to nitrite or nitrite is 1:(1-1.5); Preferably, the nitrite is selected from one or more of isoamyl nitrite, butyl nitrite, sec-butyl nitrite, isobutyl nitrite, tert-butyl nitrite, isopropyl nitrite or propyl nitrite, ethyl nitrite or methyl nitrite; And / or, in step (3), the reaction is carried out in an organic solvent. Preferably, the organic solvent is selected from one or more of DMSO, alcohol solvents, ether solvents, ester solvents, aromatic solvents, or chlorinated alkane solvents; More preferably, the alcohol solvent is selected from one or more of methanol, ethanol, isopropanol, propanol and 2,2,3,3-tetrafluoropropanol; Preferably, the ether solvent is selected from one or more of diethyl ether, tetrahydrofuran, methyltetrahydrofuran, methyl tert-butyl ether, diisopropyl ether, 1,4-dioxane, ethylene glycol dimethyl ether, ethylene glycol diethyl ether, diethylene glycol dimethyl ether, and polyethylene glycol dimethyl ether. Preferably, the ester solvent is selected from one or more of ethyl acetate, butyl acetate, sec-butyl acetate, ethyl butyrate, ethylene glycol methyl ether acetate, and propylene glycol methyl ether acetate; Preferably, the aromatic solvent is selected from one or more of benzene, toluene, and chlorobenzene; Preferably, the chloroalkane is selected from one or more of dichloromethane, 1,2-dichloroethane, chlorobenzene, and fluorobenzene; And / or, in step (3), the temperature of the reaction is 0-35°C; And / or, in step (4), the intermediates M4 and M obtained in step (3) are... 4， The mixture was recrystallized in an organic solvent to obtain a high-purity intermediate M4; And / or, in step (4), the intermediates M4 and M obtained in step (3) are... 4， The mixture was separated and purified by silica gel column chromatography to obtain high-purity intermediate M4; In step (5), the molar ratio of the high-purity intermediate M4 obtained in step (4) to CH3COCl or (CH3CO)2O is 1:(1-1.5); Preferably, the esterification reaction is carried out in an aprotic solvent, and preferably, the aprotic solvent is selected from one or more of dichloromethane, ethyl acetate, toluene, and methyl tert-butyl ether; And / or, when M4 reacts with CH3COCl, an acid-binding agent needs to be added to the reaction system. Preferably, the acid-binding agent is selected from pyridine and / or triethylamine. More preferably, the molar ratio of the acid-binding agent to the CH3COCl is (1-1.2):1; And / or, the temperature of the esterification reaction is 20-60°C.

6. A photocurable composition comprising a photoinitiator and a free radical polymerizable compound, wherein the photoinitiator comprises a stereoselective nitrocarbazolium oxime compound according to any one of claims 1-3 or a stereoselective nitrocarbazolium oxime compound obtained by the preparation method according to any one of claims 4-5. Preferably, the free radical polymerizable compound is selected from acrylate compounds, methacrylate compounds, and combinations thereof; Preferably, the free radical polymerizable compound is selected from one or more of the following: alkyl acrylate, cycloalkyl acrylate, hydroxyalkyl acrylate, dialkylaminoalkyl acrylate, alkyl methacrylate, cycloalkyl methacrylate, hydroxyalkyl methacrylate, dialkylaminoalkyl methacrylate, acrylic epoxy resin, acrylic polyester resin, unsaturated polyester resin, acrylic polyether resin, and acrylic polyurethane resin. More preferably, the free radical polymerizable compound is selected from one or more of the following: methyl acrylate, butyl acrylate, cyclohexyl acrylate, 2-hydroxyethyl acrylate, isobornyl acrylate, ethyl methacrylate, polysiloxane acrylate, diacrylate of vinyl acetate, diacrylate of styrene, diacrylate of ethylene glycol, diacrylate of polyethylene glycol, diacrylate of propylene glycol, diacrylate of neopentyl glycol, diacrylate of 1,6-hexanediol, trihydroxymethane triacrylate, pentaerythritol tetraacrylate, dipentaerythritol hexaacrylate, vinyl acrylate, and triallyl isocyanurate. And / or, the stereoselective nitrocarbazole oxime compound accounts for 0.1-4.0% by mass in the photocurable composition.

7. A photoresist, wherein the raw materials for preparing the photoresist include a photoinitiator, a multifunctional acrylate monomer, an alkali-soluble resin, and an organic solvent, wherein, The photoinitiator includes the stereoselective nitrocarbazole oxime ester compound according to any one of claims 1-3 or the stereoselective nitrocarbazole oxime ester compound obtained by the preparation method according to any one of claims 4-5. Preferably, the multifunctional acrylate monomer is selected from acrylate monomers with a functionality of ≥3, more preferably dipentaerythritol hexaacrylate and / or pentaerythritol acrylate; Preferably, the alkali-soluble resin is a resin having acidic groups, more preferably a polyacrylate or methacrylate having carboxylic acid groups, and even more preferably a copolymer formed by one or more of methacrylic acid, itaconic acid, and maleic acid with methyl acrylate, methyl methacrylate, butyl methacrylate, benzyl acrylate, benzyl methacrylate, hydroxyethyl acrylate, styrene, butadiene, and maleic anhydride, such as methyl methacrylate and methacrylate copolymer, benzyl methacrylate and methacrylate copolymer, methyl methacrylate and butyl methacrylate, and methacrylate and styrene copolymer; Preferably, the organic solvent is selected from one or more of ester solvents, aromatic solvents, and haloalkane solvents, and more preferably from one or more of propylene glycol monomethyl ether acetate, ethylene glycol monomethyl ether acetate, toluene, xylene, and tetrachloroethane; Optionally, the photoinitiator further includes one or more of the following: 2,2-dimethoxy-2-phenylacetophenone, 2-dimethylamino-2-benzyl-1-(4-morpholinylphenyl)-1-butanone, 2-dimethylamino-2-(4-methylbenzyl)-1-(4-morpholinylphenyl)-1-butanone, 2-dimethylamino-2-benzyl-1-(4-piperidinylphenyl)-1-butanone, 2,4,6-trimethylbenzoylbenzene-diphenylphosphine oxide, bis(2,4,6-trimethylbenzoyl)-phenylphosphine oxide, 2-isopropylthioxanthonone, 2,4-diethylthioxanthonone, and bis(2,6-difluoro-3-pyrrolephenyl)dicenoctanetane. Optionally, the raw materials for preparing the photoresist further contain pigments; preferably, the pigments are one or more of red pigments, green pigments, blue pigments, or black pigments; more preferably, the red pigments include CI Pigment Red 177; preferably, the green pigments include CI Pigment Green 7; preferably, the blue pigments include CI Pigment Blue 15:6 and Solvent Blue 25; preferably, the black pigments include carbon black, titanium black, and CI Pigment Black 1. Preferably, the raw materials for preparing the photoresist further include heat stabilizers and / or light stabilizers.

8. A black matrix prepared from the photoresist of claim 7, wherein, The pigment in the photoresist is a black pigment, preferably carbon black or titanium black.

9. A color filter device, which is fabricated from the photoresist of claim 7 or the black matrix of claim 8, wherein, The pigment in the photoresist is a red pigment, a green pigment, or a blue pigment.

10. A display obtained by photocuring a stereoselective nitrocarbazole oxime ester compound as described in any one of claims 1-3 or a stereoselective nitrocarbazole oxime ester compound obtained by the preparation method described in any one of claims 4-5 as a photoinitiator; preferably, the display includes a PCB display, an LCD display, and an OLED display.

11. The use of the stereoselective nitrocarbazole oxime ester compound of any one of claims 1-3, the stereoselective nitrocarbazole oxime ester compound obtained by the preparation method of any one of claims 4-5, the photocurable composition of claim 6, or the photoresist of claim 7 in the preparation of colored or uncolored inks, coatings, adhesives, filters, displays, pattern printing, printing plates, 3D printing, PCB photoresist, PCB solder resist ink, substrate protective coating, electronic device protective coating, passivation film, liquid or dry film resist material, sealant, dental material, optical material, optical film, fiber optic coating, insulating film, polarizer, microscope lens, and recording material.

12. An adhesive comprising the photocurable composition of claim 6, Preferably, the adhesive further includes one or more of a polymer, stabilizer, surfactant, leveling agent, and dispersant. Preferably, the polymer has a weight-average molecular weight of 5,000-100,000.

13. An optical spacer, prepared by the photoresist of claim 7, wherein, The pigment in the photoresist is a black pigment, preferably carbon black or titanium black.

14. A printed article, which is obtained by photocuring with a stereoselective nitrocarbazole oxime ester compound as described in any one of claims 1-3 or a stereoselective nitrocarbazole oxime ester compound obtained by the preparation method described in claim 4 or 5 as a photoinitiator; Preferably, the printed article includes a printed circuit board and a color filter.

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