A synthesis method of oxime ester photoacid generator compounds

Abstract

This invention relates to the field of organic chemical synthesis technology, specifically to a method for synthesizing oxime ester-type photoacid-producing compounds. The method includes: etherifying phenol with 1,3-dihalopropane in an alkaline environment and an organic solvent, followed by post-treatment to obtain 1,3-diphenoxypropane; then, in an organic solvent, reacting it with a trifluoroacetylation reagent under Lewis acid catalysis to undergo a Friedel-Crafts acylation reaction, followed by quenching and post-treatment to obtain a bis(trifluoroacetyl) product; oximating the bis(trifluoroacetyl) product with an oximeation reagent in an organic solvent, followed by post-treatment to obtain a bis(oxime) product; and then subjecting the obtained bis(oxime) product to a sulfonation reaction with a propylsulfonation reagent in an alkaline environment and an organic solvent, followed by washing with water, distillation, and recrystallization purification to obtain the target oxime ester-type photoacid-producing compound. This method solves the problems of complex processes, difficult purification, limited raw materials, high costs, and difficulty in meeting the needs of industrial production in traditional oxime ester-type photoacid-producing agent synthesis methods.

Description

Technical Field

[0001] This invention relates to the field of organic chemical synthesis technology, specifically to a method for synthesizing oxime ester photoacid-producing compounds. Background Technology

[0002] Photoacid generators are compounds that decompose under light radiation, such as ultraviolet or visible light, to produce protonated acids or Lewis acids. After absorbing light energy, these compounds release acids through photochemical reactions, thereby initiating or catalyzing subsequent chemical reactions. With the advent of chemical amplification technology, the application range of photoacid generators has significantly expanded, playing a crucial role, especially in cationic polymerization systems and chemically amplified photoresists. In photolithography, the acids generated by photoacid generators catalyze the deprotection reaction of polymer films, creating a solubility difference between exposed and unexposed areas, achieving high-resolution patterning. Furthermore, photoacid generators can release protons in a controlled manner, causing changes in the local pH value. This property shows potential value in regulating the biological microenvironment and controlling biochemical reactions, and has gradually gained attention in recent years in fields such as anti-tumor research, antibacterial applications, and biosensors.

[0003] Oxime esters, as an important class of photoacid-producing agents, have been extensively studied due to their excellent thermal stability, photosensitivity, and acid-producing efficiency. These compounds typically require the introduction of specific functional groups into their molecular structure to ensure efficient cleavage and release of sulfonic acids or other strong acids under light irradiation. While some synthetic routes for oxime esters have been reported, most methods suffer from complex processes and purification difficulties. For example, some synthetic routes require cumbersome separation methods such as column chromatography for product purification, which is not only time-consuming but also consumes large amounts of solvent, resulting in high production costs and making it difficult to meet the needs of industrial production. Furthermore, existing processes often involve limited raw material sources or demanding reaction conditions, requiring sophisticated equipment, further limiting their large-scale application. Therefore, developing a simple, mild, and easily industrially feasible synthetic method for oxime esters is of great significance for promoting their application in related fields. Summary of the Invention

[0004] This application provides a method for synthesizing oxime ester photoacid-producing compounds to solve the problems of complex processes, difficult purification, limited raw materials, high costs, and difficulty in meeting the needs of industrial production in traditional oxime ester photoacid-producing compound synthesis methods.

[0005] This application provides a method for synthesizing an oxime ester photoacid-producing compound, comprising: Step 1: Using phenol and 1,3-dihalopropane as raw materials, an etherification reaction is carried out in an organic solvent under the action of alkali. The reaction temperature is controlled at 50~100℃. After the reaction is completed, the etherified product 1,3-diphenoxypropane is obtained through post-treatment. Step 2: Dissolve the etherified product 1,3-diphenoxypropane in an organic solvent, and add a trifluoroacetylation reagent at -20~20℃ under Lewis acid catalysis to carry out a Friedel-Crafts acylation reaction. After the reaction is completed, the product is quenched and post-treated to obtain the bistrifluoroacetyl-substituted Friedel-Crafts product. Step 3: Dissolve the Friedel-Crafts product in an organic solvent and carry out an oxime reaction with an oxime reagent. The reaction temperature is controlled at 10~60℃. After the reaction is completed, post-treatment is performed to obtain the bisoxime-substituted oxime product. Step 4: Dissolve the oxime product in an organic solvent and carry out a sulfonation reaction with a propyl sulfonating agent under the action of an alkali. The reaction temperature is controlled at -10~30℃. After the raw material reaction is completed, the crude product is obtained by washing with water and distillation. The crude product is then purified by solvent recrystallization to obtain the target oxime ester photoacid-producing compound.

[0006] Optionally, in step one, the 1,3-dihalopropane is any one of 1,3-dibromopropane, 1,3-dichloropropane, or 1,3-diiodopropane; the molar ratio of phenol, 1,3-dihalopropane, and base is 1:0.4~2.5:2~5; the base is one or more of sodium carbonate, potassium carbonate, potassium phosphate, sodium bicarbonate, potassium bicarbonate, potassium hydroxide, sodium hydroxide, and triethylamine, and can be used in conjunction with 4-dimethylaminopyridine (DMAP) catalysis.

[0007] Optionally, in step one, the organic solvent is one or more of toluene, methanol, acetonitrile, and N,N-dimethylformamide, which can be used in combination with water; after the reaction is completed, process water is added, and the mixture is extracted with ethyl acetate. The solvent is removed by organic phase distillation to obtain the 1,3-diphenoxypropane intermediate without the need for column chromatography purification.

[0008] Optionally, in step two, the Lewis acid is one or more of aluminum chloride, boron trifluoride, trimethylaluminum, ferrous chloride, copper chloride, zinc chloride, or ferric chloride; the trifluoroacetylation reagent is one or more of trifluoroacetyl chloride, S-trifluoroacetyl dibenzothiophenonium salt, or trifluoroacetic anhydride; and the molar ratio of the etherification product, Lewis acid, and trifluoroacetylation reagent is 1:2~5:2~8.

[0009] Optionally, in step two, the trifluoroacetylation reagent is added dropwise, and the system temperature is maintained at -20~20℃ during the dropwise addition. After the dropwise addition is completed, the reaction is kept at the temperature until the raw material is completely converted. After the reaction is completed, process water is added to quench the reaction, and the mixture is allowed to stand and separate. The organic phase is distilled to remove the solvent. The obtained bis(trifluoroacetyl) substituted Friedel-Crafts product can be directly used for oxime reaction without the need for column chromatography purification. The organic solvent is one or more of toluene, acetonitrile, dichloromethane, and N,N-dimethylformamide.

[0010] Optionally, in step three, the oxime reagent is one or more of hydroxylamine sulfate, hydroxylamine hydrochloride, hydroxylamine acetate, and a 50% aqueous solution of hydroxylamine; the molar ratio of the Friedel-Crafts product to the oxime reagent is 1:2 to 16; and the organic solvent is one or more of methanol, ethanol, water, dichloromethane, acetone, toluene, and acetonitrile.

[0011] Optionally, in step three, after the reaction is complete, the solvent is removed by distillation, the crude product is added to process water for pulping, and after filtration, the bisoxime-substituted oxime product is obtained, which can be directly used for sulfonyl esterification reaction without the need for column chromatography purification.

[0012] Optionally, in step four, the propylsulfonating agent is one or both of N-propanesulfonyl imidazole or propylsulfonyl chloride; the base is one or more of sodium carbonate, potassium carbonate, potassium phosphate, sodium bicarbonate, potassium bicarbonate, potassium hydroxide, sodium hydroxide, and triethylamine, which can be used in conjunction with 4-dimethylaminopyridine (DMAP) catalysis; the molar ratio of the oxime product, propylsulfonating agent, and base is 1:2~16:2~16; and the organic solvent is one or more of dichloromethane, acetone, tetrahydrofuran, methyl tert-butyl ether, and acetonitrile.

[0013] Optionally, in step four, the solvent used for recrystallization purification is one or more of acetonitrile, methanol, toluene, ethanol, pure water, isopropanol, isopropyl ether, or n-heptane; the recrystallization process is as follows: the crude product is added to the purification solvent, heated to the reflux temperature and stirred until completely dissolved, then cooled to 0~20℃, the precipitated solid is filtered and dried to obtain the target product.

[0014] Optionally, the target oxime ester photoacid-producing compound is 1,1'-[1,3-propanediylbis(oxy-4,1-phenylene)]bis[2,2,2-trifluoroethylone]1,1'-bis[O-(propylsulfonyl)oxime]; the synthesis method involves four steps without column chromatography purification, and the product is subjected to... 1 HNMR characterization is consistent with the target structure.

[0015] Therefore, this application has at least the following beneficial effects: (1) The embodiments of this application employ a four-step continuous reaction process, using phenol and 1,3-dihalopropane as starting materials, to generate a 1,3-diphenoxypropane intermediate via etherification. The etherification reaction is carried out in an organic solvent under alkaline conditions. The phenolic hydroxyl group of phenol undergoes a nucleophilic substitution reaction with the haloalkane to form a biphenyl ring structure linked by an ether bond. This intermediate has a symmetrical molecular configuration, providing an ideal dual-site reactive center for the subsequent Friedel-Crafts acylation reaction. In the Friedel-Crafts acylation reaction, the Lewis acid forms an electrophilic complex with the trifluoroacetylating reagent. This complex directionally attacks the para carbon atom of the benzene ring, achieving highly selective substitution of the bifluoroacetyl group and generating a symmetrical bifluoroacetyl-substituted Friedel-Crafts product. In the oxime reaction stage, the carbonyl group of the trifluoroacetyl group undergoes a nucleophilic addition-elimination reaction with the hydroxylamine to generate a stable oxime structure. This reaction can be efficiently completed under mild conditions of 10~60℃, with controllable reaction conditions and few side reactions. Finally, the oxime group undergoes a sulfonation reaction with the propylsulfonating agent to form the target oxime ester structure. The entire process route is rationally designed, with high selectivity in each step, few side reactions, and high-purity products can be obtained without column chromatography purification throughout the process. This significantly improves the simplicity and operability of the process route and enhances the feasibility of industrial scale-up. (2) The embodiments of this application achieve precise control of process parameters by optimizing the molar ratio and reaction conditions of each step of the reaction, which greatly improves the reaction efficiency and raw material conversion rate. In the etherification reaction, the molar ratio of phenol to 1,3-dihalopropane is controlled in the range of 1:0.4~2.5, which not only ensures the formation advantage of the dietherification product, but also avoids the excessive generation of the single etherification by-product, and adapts to the reaction requirements of different active haloalkanes. In the Friedel-Crafts acylation reaction, the molar ratio of the etherification product to Lewis acid and trifluoroacetylation reagent is controlled in the range of 1:2~5 and 1:2~8, respectively. The synergistic effect of Lewis acid and acetylation reagent ensures the complete conversion of diacetylation; the reaction temperature is controlled between -20~20℃, which can effectively suppress the occurrence of side reactions such as ortho substitution and improve the selectivity of para substitution. In the oximation reaction, the molar ratio of Friedel-Crafts product to oximating agent is controlled within the range of 1:2 to 16. An appropriate excess of the oximating agent ensures complete oximation of the dicarbonyl group, avoiding the residue of the monooximation intermediate. In the sulfonation reaction, the molar ratio of oximation product to propylsulfonating agent and base is controlled within the ranges of 1:2 to 16 and 1:2 to 16, respectively. The base acts as an acid-binding agent, rapidly neutralizing the acidic byproducts generated in the reaction, preventing product hydrolysis, and simultaneously shifting the esterification equilibrium to the forward direction, thus improving the reaction conversion rate. Through the optimized combination of molar ratios in each step, the utilization rate of raw materials is significantly improved, and production costs are significantly reduced. (3) The synthesis process used in this application does not require column chromatography purification throughout the entire process. The intermediates in each step can be obtained with the required purity for the next reaction by simple extraction, washing, distillation or slurrying, which significantly improves the industrial applicability and ease of operation of the process. After the etherification reaction, the solvent and unreacted raw materials are removed by ethyl acetate extraction combined with distillation to directly obtain the 1,3-diphenoxypropane intermediate. After the Friedel-Crafts reaction, Lewis acid and excess acetylation reagent are removed by water quenching, standing separation and organic phase distillation. The obtained bis(trifluoroacetyl) substituted Friedel-Crafts product can be directly used for oxime reaction. After the oxime reaction, the solvent is removed by distillation. The crude product is added to process water and slurryed. Water-soluble impurities are effectively removed. After filtration, a high-purity bis(oxime) substituted oxime product is obtained. After the sulfonyl esterification reaction, the crude product is obtained by washing with water and distillation. Finally, the target product is obtained by recrystallization purification. This purification strategy effectively avoids the limitations of column chromatography, such as large solvent consumption, cumbersome operation, long production cycle, and inability to achieve continuous production, thus significantly reducing production costs and environmental pressure. (4) The recrystallization purification process in this application uses common industrial solvents such as acetonitrile, methanol, ethanol, and isopropanol, achieving deep purification of the product through heating to dissolve and cooling to precipitate. During recrystallization, the target product is completely dissolved in the purification solvent at high temperature. After cooling, crystals slowly precipitate due to decreased solubility, while impurities remain in the mother liquor due to higher solubility or differences in crystallization habits. By controlling the cooling rate and final temperature, a near-white solid product with complete crystal structure and uniform particle size can be obtained. The purified product is then subjected to… 1 ¹H NMR characterization showed that the characteristic peaks completely matched the target structure, confirming the correctness of the product structure. HPLC analysis showed that the product purity was ≥97%, confirming that the process can stably prepare high-purity target products. This recrystallization process is simple to operate, the solvent can be recycled, the product quality is stable, and the batch-to-batch reproducibility is good, significantly enhancing the reliability of large-scale production. (5) The synthesis method of this application has a wide range of raw material applicability and flexible process adjustment space. The etherification reaction can use a variety of haloalkanes such as 1,3-dibromopropane, 1,3-dichloropropane or 1,3-diiodopropane. The choice of base covers a variety of inorganic and organic bases such as sodium carbonate, potassium carbonate, sodium hydroxide, and triethylamine. The solvent can be common organic solvents such as acetonitrile, toluene, methanol, and N,N-dimethylformamide. The reaction temperature can be adjusted in the range of 50~100℃. The Lewis acid for the Friedel-Crafts reaction can be selected from a variety of types such as aluminum chloride, ferric chloride, zinc chloride, and trimethylaluminum. The trifluoroacetylation reagent can be selected from trifluoroacetyl chloride, S-trifluoroacetyl dibenzothiophenonium salt or trifluoroacetic anhydride. The reaction temperature can be precisely controlled in the range of -20~20℃. The oxime reagent for the oxime reaction can be selected from hydroxylamine sulfate, hydroxylamine hydrochloride, hydroxylamine acetate, and 50% hydroxylamine aqueous solution. The solvent can be selected from a variety of types such as methanol, ethanol, acetone, toluene, and acetonitrile. The propylsulfonating agent for the sulfonation reaction can be N-propanesulfonyl imidazole or propylsulfonyl chloride, and the base types cover both inorganic and organic bases, which can be used in conjunction with DMAP catalysis. This multi-parameter adjustable process design provides ample operational space for process optimization and quality control during production, facilitating adaptive adjustments based on different raw material batches and equipment conditions, and significantly improving the flexibility and applicability of the process; (6) The synthesis method in this application conforms to the concepts of green chemistry and sustainable development. Each reaction step is carried out under mild conditions, without the need for high temperature, high pressure or highly corrosive reagents. The production process has low energy consumption and high operational safety, significantly enhancing the environmental friendliness and safety of the process. The amount of wastewater and waste liquid generated during the reaction is small and can meet the emission standards through simple treatment. Organic solvents such as ethyl acetate, dichloromethane, and ethanol can be recycled after conventional distillation, greatly reducing solvent consumption and waste generation, and improving resource utilization efficiency. The entire process has high reaction selectivity and few by-products, effectively improving the effective utilization rate of raw materials and high environmental friendliness. In the context of increasingly stringent environmental protection requirements, this process significantly enhances its competitive advantage and application value in industrial production.

[0016] This solves the problems of complex processes, difficult purification, limited raw materials, high costs, and difficulty in meeting the needs of industrial production in the traditional synthesis methods of oxime ester photoacid generators.

[0017] Additional aspects and advantages of this application will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of this application. Attached Figure Description

[0018] The above and / or additional aspects and advantages of this application will become apparent and readily understood from the following description of the embodiments taken in conjunction with the accompanying drawings, wherein: Figure 1This is a synthetic route diagram of oxime ester photoacid-producing compounds provided in the embodiments of this application; Figure 2 The above is the 1H NMR spectrum of the oxime ester photoacid generator provided in Example 1 of this application; Figure 3 The liquid chromatography-mass spectrometry chromatogram of the oxime ester photoacid generator provided in Example 1 of this application; Figure 4 MS mass spectrum of the oxime ester photoacid generator provided in Example 1 of this application; Figure 5 The image shows the nuclear magnetic resonance fluorine spectrum of the oxime ester photoacid generator provided in Example 1 of this application. Detailed Implementation

[0019] The technical solutions in the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. All other embodiments obtained by those skilled in the art based on the embodiments of this application without creative effort are within the scope of protection of this application.

[0020] In the embodiments of this application, unless otherwise specified, the raw materials or processing techniques are all conventional commercially available raw materials or conventional processing techniques in the art.

[0021] The present application will now be described with reference to specific embodiments. It should be noted that these embodiments are merely descriptive and do not limit the present application in any way.

[0022] Example 1 This application provides a method for synthesizing oxime ester photoacid-producing compounds, such as... Figure 1 As shown, it includes: Step 1: Using phenol and 1,3-dibromopropane as raw materials, an etherification reaction was carried out in acetonitrile solvent under the action of sodium carbonate. The reaction temperature was controlled at 60℃ and the reaction time was 6h. After the reaction was completed, the etherified product 1,3-diphenoxypropane was obtained through post-treatment.

[0023] The feed amounts of phenol, 1,3-dibromopropane and sodium carbonate are 100g (1.06mol), 108g (0.53mol) and 125g (2.66mol) respectively, and the molar ratio of the three is 1:0.5:2.51.

[0024] It should be noted that the organic solvent is acetonitrile, and the volume is 500 mL. After the reaction is completed, 200 g of process water is added, and 200 g of ethyl acetate is used for extraction. The solvent is removed by distillation of the organic phase to obtain the 1,3-diphenoxypropane intermediate, which does not require column chromatography purification.

[0025] It is understood that in the embodiments of this application, 1,3-dibromopropane with suitable reactivity is selected as the haloalkane raw material, sodium carbonate is used as the acid-binding agent, and acetonitrile is used as the homogeneous reaction solvent. With a precise molar ratio of 1:0.5:2.51 and mild reaction conditions of 60℃ and 6h, the bimolecular nucleophilic substitution reaction of phenol hydroxyl group and haloalkane can be promoted with high selectivity, preferentially generating the symmetrical dietherified target product and effectively suppressing the generation of monosubstituted byproducts. At the same time, the simple post-processing method of extraction-distillation is adopted, which can obtain the intermediate that meets the requirements of subsequent reactions without the need for column chromatography purification. This avoids the problems of large solvent consumption and cumbersome operation caused by column chromatography, and can completely preserve the symmetrical diphenyl ring structure of the intermediate, providing a uniform and highly active dual-site reaction center for the subsequent Friedel-Crafts acylation reaction, ensuring the consistency and complete conversion of the subsequent bifunctional group substitution.

[0026] Step 2: The etherified product 1,3-diphenoxypropane was dissolved in dichloromethane solvent, and under the catalysis of aluminum trichloride, trifluoroacetic anhydride was added to carry out a Friedel-Crafts acylation reaction at 0~10℃ for 10h. After the reaction was completed, the product was quenched and post-treated to obtain the bis(trifluoroacetyl) substituted Friedel-Crafts product.

[0027] The amounts of the etherified product, aluminum trichloride, and trifluoroacetic anhydride fed were 100g (0.44mol), 240g (1.80mol), and 276g (1.31mol), respectively, with a molar ratio of 1:4.09:2.98.

[0028] It should be noted that aluminum trichloride was added in batches, and trifluoroacetic anhydride was added dropwise. During the dropwise addition, the system temperature was maintained at 0~10℃. After the dropwise addition was completed, the reaction was kept at the temperature until the raw material was completely converted. After the reaction was completed, process water was added to quench the reaction, and the mixture was allowed to stand and separate. The organic phase was distilled to remove the solvent. The obtained bis(trifluoroacetyl) substituted Friedel-Crafts product was directly used for the oxime reaction without the need for column chromatography purification. The organic solvent was dichloromethane, and the volume was 1000 mL.

[0029] It is understood that in the embodiments of this application, aluminum trichloride is selected as a highly active Lewis acid catalyst, and trifluoroacetic anhydride is used as an acylation reagent. Through precise molar ratio of 1:4.09:2.98 and process control of low-temperature dropwise addition and heat preservation reaction at 0~10℃, a stable electrophilic complex can be formed between the Lewis acid and the acylation reagent. This complex directionally attacks the para carbon atom of the benzene ring, achieving highly selective symmetrical substitution of the bis(trifluoroacetyl) group, effectively suppressing side reactions such as ortho-substitution, and ensuring complete conversion of the bifunctional group. At the same time, a simple post-treatment method of water quenching-liquid extraction-distillation is adopted, which eliminates the need for column chromatography purification and allows the intermediate to be directly added to the next reaction step. This greatly simplifies the production process, shortens the production cycle, and completely preserves the bicarbonyl active structure of the intermediate, providing highly active dual reaction sites for the subsequent oxime reaction and ensuring complete conversion of the intermediate in the subsequent oxime reaction.

[0030] Step 3: The Friedel-Crafts product was dissolved in ethanol and oximated with hydroxylamine hydrochloride. The reaction temperature was controlled at 40°C and the reaction time was 10 h. After the reaction was completed, the bisoxime-substituted oximated product was obtained through post-treatment.

[0031] The amounts of Friedel-Crafts product and hydroxylamine hydrochloride were 100g (0.24mol) and 66g (0.95mol), respectively, with a molar ratio of 1:3.96.

[0032] It should be noted that the organic solvent is ethanol, and the amount used is 500 mL. After the reaction is completed, the solvent is removed by distillation, and the crude product is added to 200 mL of process water for slurrying. After filtration, the bisoxime-substituted oxime product is obtained, which can be directly used for sulfonyl esterification reaction without the need for column chromatography purification.

[0033] It is understood that in the embodiments of this application, hydroxylamine hydrochloride is selected as a stable and readily available oxime reagent, and ethanol is selected as a homogeneous reaction solvent that is miscible with water. With a suitable molar ratio of 1:3.96 and mild reaction conditions of 40°C and 10h, the carbonyl group of trifluoroacetyl can undergo a complete nucleophilic addition-elimination reaction with hydroxylamine, generating a stable dioxime structure with high selectivity and no obvious side reactions. At the same time, a simple post-treatment method of distillation to remove solvent and water slurry filtration can efficiently remove water-soluble impurities and excess oxime reagent. High-purity intermediates can be obtained without column chromatography purification and directly fed into the next step of sulfonyl esterification reaction. This simplifies the process operation and completely preserves the reactivity of the dioxime group, providing a precise reaction site for the synthesis of the final target product and ensuring the selectivity and conversion rate of the final esterification reaction.

[0034] Step 4: Dissolve the oxime product in dichloromethane solvent, and carry out sulfonation reaction with N-propanesulfonyl imidazole in the presence of triethylamine. The reaction temperature is controlled at 10℃ and the reaction time is 3h. After the raw material reaction is completed, the crude product is obtained by washing with water and distillation, and then purified by solvent recrystallization to obtain the target oxime ester photoacid-producing compound.

[0035] The amounts of the oxime product, N-propanesulfonyl imidazole, and triethylamine were 100g (0.22mol), 348g (2.0mol), and 67.4g (0.66mol), respectively, with a molar ratio of 1:9.09:3.

[0036] It should be noted that the organic solvent is dichloromethane, and the amount used is 100 mL. After the reaction is complete, 100 mL of process water is added, and the mixture is allowed to stand and separate. The organic phase is evaporated to dryness to obtain the crude product. The solvent used for recrystallization purification is methanol, and the amount used is 500 mL of methanol per 100 g of crude product. The recrystallization process is as follows: the crude product is added to the purification solvent, heated to 65 °C and stirred until completely dissolved, then cooled to 20 °C. After the solid precipitates, it is filtered and dried to obtain the target product.

[0037] It is understood that in this application embodiment, N-propanesulfonyl imidazole is selected as a highly selective sulfonating reagent, combined with triethylamine as an acid-binding agent and dichloromethane as a reaction solvent. With an appropriate molar ratio of 1:9.09:3 and mild reaction conditions of 10°C and 3h, the acidic byproducts generated by the reaction can be quickly neutralized, avoiding the hydrolysis and deactivation of the oxime group. At the same time, it promotes the complete esterification reaction of the oxime group and the sulfonating reagent, generating the target oxime ester structure with high selectivity, few side reactions and high reaction efficiency. The subsequent simple post-treatment of water washing and distillation to remove solvent, combined with recrystallization purification with methanol as a single solvent, does not require column chromatography purification throughout the process, and can obtain high-purity target products. This not only greatly reduces the cost of industrial production and environmental pressure, but also allows for precise control of product crystal form and purity. The NMR characterization confirms that the product structure is completely consistent with the design target, which can stably meet the application requirements of photoacid generators for photoresists. At the same time, the process is simple to operate and the parameters are controllable, making it suitable for industrial scale-up production.

[0038] The target product in this embodiment is... 1 HNMR (400MHz, DMSO) characterization showed that the characteristic peaks were completely consistent with the target structure.

[0039] Example 2 This application provides a method for synthesizing oxime ester photoacid-producing compounds, such as... Figure 1 As shown, it includes: Step 1: Using phenol and 1,3-dichloropropane as raw materials, an etherification reaction was carried out in methanol solvent under the action of potassium carbonate. The reaction temperature was controlled at 60℃ and the reaction time was 12h. After the reaction was completed, the etherified product 1,3-diphenoxypropane was obtained through post-treatment.

[0040] The feed amounts of phenol, 1,3-dichloropropane and potassium carbonate were 100g (1.06mol), 108g (0.96mol) and 290g (2.1mol) respectively, with a molar ratio of 1:0.91:1.98.

[0041] It should be noted that the organic solvent is methanol, and the volume is 500 mL. After the reaction is completed, 200 g of process water is added, and 200 g of ethyl acetate is used for extraction. The solvent is removed by distillation of the organic phase to obtain the 1,3-diphenoxypropane intermediate, which does not require column chromatography purification.

[0042] Understandably, in this embodiment, 1,3-dichloropropane, a readily available and inexpensive industrial raw material, is selected as the haloalkane feedstock. Potassium carbonate is used as an acid-binding agent, and methanol is used as a low-cost universal solvent. With an appropriate molar ratio of 1:0.91:1.98 and reaction conditions of 60°C and 12h, the complete dietherification reaction can be stably promoted under a low-cost feedstock system, effectively controlling the formation of monosubstituted byproducts and ensuring the yield and purity of the target intermediate. At the same time, a simple post-processing method of extraction-distillation is adopted, which eliminates the need for column chromatography purification to obtain intermediates that meet the requirements of subsequent reactions. This significantly reduces the cost of raw material procurement and process operation, adapting to the cost control requirements of large-scale industrial production. In addition, the generated symmetrical dibenzene ring intermediate has a stable structure, which can provide a stable reaction site for the subsequent Friedel-Crafts acylation reaction, ensuring the stable progress of subsequent processes.

[0043] Step 2: The etherified product 1,3-diphenoxypropane was dissolved in dichloromethane solvent. Under the catalysis of zinc chloride, trifluoroacetyl chloride was added at 20°C to carry out the Friedel-Crafts acylation reaction for 10 hours. After the reaction was completed, the product was quenched and post-treated to obtain the bistrifluoroacetyl-substituted Friedel-Crafts product.

[0044] The amounts of the etherified product, zinc chloride, and trifluoroacetyl chloride were 100g (0.4mol), 272.6g (2.0mol), and 198.7g (1.5mol), respectively, with a molar ratio of 1:5:3.75.

[0045] It should be noted that zinc chloride was added in batches, and trifluoroacetyl chloride was added dropwise. The system temperature was maintained at 20°C during the dropwise addition. After the dropwise addition was completed, the reaction was kept at the temperature until the raw material was completely converted. After the reaction was completed, process water was added to quench the reaction, and the mixture was allowed to stand and separate. The organic phase was distilled to remove the solvent. The obtained bis(trifluoroacetyl) substituted Friedel-Crafts product was directly used for the oxime reaction without the need for column chromatography purification. The organic solvent was dichloromethane, and the volume was 1000 mL.

[0046] It is understood that in the embodiments of this application, zinc chloride, which is stable and industrially available, is selected as a Lewis acid catalyst, and trifluoroacetyl chloride is selected as a highly efficient acylation reagent. By using an appropriate molar ratio of 1:5:3.75 and a process control of adding the reagent at room temperature (20°C) and maintaining the temperature, highly selective symmetrical substitution of bis(trifluoroacetyl) groups can be achieved at room temperature. This eliminates the need for cryogenic refrigeration equipment, significantly reducing energy consumption and equipment investment in industrial production. At the same time, a simple post-treatment method of water quenching-liquid extraction-distillation is adopted, which eliminates the need for column chromatography purification and allows the intermediate to be directly added to the next reaction step. This simplifies the process operation, shortens the production cycle, and the generated dicarbonyl intermediate has a complete structure and stable activity, providing a reliable dual reaction site for subsequent oxime reactions and ensuring stable conversion in subsequent reactions.

[0047] Step 3: The Friedel-Crafts product was dissolved in toluene and oximated with hydroxylamine sulfate. The reaction temperature was controlled at 60°C and the reaction time was 10 h. After the reaction was completed, the bisoxime-substituted oximated product was obtained through post-treatment.

[0048] The amounts of Friedel-Crafts product and hydroxylamine sulfate were 100g (0.2mol) and 492g (3.0mol), respectively, with a molar ratio of 1:15.

[0049] It should be noted that the organic solvent is toluene, and the amount used is 500 mL. After the reaction is completed, the solvent is removed by distillation, and the crude product is added to 200 mL of process water for slurrying. After filtration, the bisoxime-substituted oxime product is obtained, which can be directly used for sulfonyl esterification reaction without the need for column chromatography purification.

[0050] It is understood that in the embodiments of this application, hydroxylamine sulfate is used as an oxime reagent, and toluene is used as a water-carrying reaction solvent. With an excess feed ratio of 1:15 and reaction conditions of 60°C and 10h, the complete oxime conversion of the dicarbonyl group can be promoted. The toluene solvent can drive the reaction equilibrium to the forward direction through water-carrying effect, ensuring the complete formation of the dioxime structure. At the same time, the simple post-treatment method of distillation to remove solvent and water slurry filtration can efficiently remove water-soluble impurities and excess oxime reagent. High-purity intermediates can be obtained without column chromatography purification and directly used in the next reaction. This not only meets the needs of industrial bulk raw material use, but also ensures the reactivity of the intermediates, laying the foundation for the smooth progress of the final esterification reaction.

[0051] Step 4: Dissolve the oxime product in tetrahydrofuran solvent, and carry out sulfonyl esterification reaction with propylsulfonyl chloride in the presence of sodium carbonate. The reaction temperature is controlled at 5°C and the reaction time is 4 hours. After the raw material reaction is completed, the crude product is obtained by washing with water and distillation, and then purified by solvent recrystallization to obtain the target oxime ester photoacid-producing compound.

[0052] The amounts of the oxime product, propylsulfonyl chloride, and sodium carbonate were 100g (0.2mol), 66.5g (0.466mol), and 106g (1.0mol), respectively, with a molar ratio of 1:2.33:5.

[0053] It should be noted that the organic solvent is tetrahydrofuran, and the amount used is 500 mL. After the reaction is complete, 100 mL of process water is added, and the mixture is allowed to stand and separate. The organic phase is evaporated to dryness to obtain the crude product. The solvent used for recrystallization purification is a mixed solvent of ethanol and n-heptane, and the amount used is 500 mL of ethanol and 100 mL of n-heptane per 100 g of crude product. The recrystallization process is as follows: the crude product is added to the purification solvent, heated to 78 °C and stirred until completely dissolved, then cooled to 20 °C. After the solid precipitates, it is filtered and dried to obtain the target product.

[0054] It is understood that in this embodiment, industrially common and low-cost propylsulfonyl chloride is selected as the sulfonating reagent, sodium carbonate is used as the inorganic acid-binding agent, and tetrahydrofuran is used as the reaction solvent. With an appropriate molar ratio of 1:2.33:5 and reaction conditions of 5℃ and 4h, the hydrogen chloride byproduct generated in the reaction can be efficiently neutralized, promoting the complete sulfonation reaction of the oxime group and generating the target oxime ester structure with high selectivity. The raw material cost is low and the reaction efficiency is high. The subsequent simple post-treatment of water washing and distillation is used, and the product is purified by recrystallization with a mixed solvent of ethanol and n-heptane. The entire process does not require column chromatography purification, and high-purity target product can be obtained. This not only achieves the adaptation of large-scale industrial raw materials throughout the process, which greatly reduces the cost of industrial production, but also allows for precise control of product purity and crystal form. The NMR characterization confirms that the product structure is completely consistent with the design target, and the process parameters are stable and controllable, which can be directly scaled up to the industrial production scale of hundreds of tons.

[0055] The target product in this embodiment is... 1 HNMR (400MHz, DMSO) characterization showed that the characteristic peaks were completely consistent with the target structure.

[0056] Example 3 This application provides a method for synthesizing oxime ester photoacid-producing compounds, such as... Figure 1 As shown, it includes: Step 1: Using phenol and 1,3-diiodopropane as raw materials, an etherification reaction was carried out in acetonitrile solvent under the action of potassium hydroxide. The reaction temperature was controlled at 60℃ and the reaction time was 6h. After the reaction was completed, the etherified product 1,3-diphenoxypropane was obtained through post-treatment.

[0057] The feed amounts of phenol, 1,3-diiodopropane and potassium hydroxide were 100g (1.06mol), 740g (2.50mol) and 168g (3.00mol) respectively, with a molar ratio of 1:2.36:2.83.

[0058] It should be noted that the organic solvent is acetonitrile, and the volume is 500 mL. After the reaction is completed, 200 g of process water is added, and 200 g of ethyl acetate is used for extraction. The solvent is removed by distillation of the organic phase to obtain the 1,3-diphenoxypropane intermediate, which does not require column chromatography purification.

[0059] It is understood that in the embodiments of this application, highly reactive 1,3-diiodopropane is selected as the haloalkane raw material, combined with potassium hydroxide as a strong base acid-binding agent and acetonitrile as a homogeneous reaction solvent. Through a wide range of molar ratios of 1:2.36:2.83 and reaction conditions of 60°C and 6h, the dietherification reaction can be rapidly completed in a highly reactive raw material system. Even with a significant excess of haloalkane, the target dietherified product can be stably generated, verifying the wide parameter tolerance of the etherification reaction process. At the same time, a simple post-processing method of extraction-distillation is adopted, and intermediates that meet the requirements of subsequent reactions can be obtained without the need for column chromatography purification. This proves the wide adaptability of this process to different reactive haloalkane raw materials, which can provide sufficient operating space for process adjustment of different raw material batches in industrial production. In addition, the generated symmetrical dibenzene ring intermediate has a stable structure and can stably adapt to the process requirements of subsequent Friedel-Crafts acylation reactions.

[0060] Step 2: The etherified product 1,3-diphenoxypropane was dissolved in dichloromethane solvent. Under the catalysis of ferric chloride, trifluoroacetyl chloride was added at 20°C to carry out the Friedel-Crafts acylation reaction for 5 hours. After the reaction was completed, the product was quenched and post-treated to obtain the bis(trifluoroacetyl) substituted Friedel-Crafts product.

[0061] The amounts of the etherified product, ferric chloride, and trifluoroacetyl chloride fed were 100g (0.41mol), 324g (2.0mol), and 276g (2.08mol), respectively, with a molar ratio of 1:4.88:5.07.

[0062] It should be noted that ferric chloride was added in batches, and trifluoroacetyl chloride was added dropwise. The system temperature was maintained at 20°C during the dropwise addition. After the dropwise addition was completed, the reaction was kept at this temperature until the raw material was completely converted. After the reaction was completed, process water was added to quench the reaction, and the mixture was allowed to stand and separate. The organic phase was distilled to remove the solvent. The obtained bis(trifluoroacetyl) substituted Friedel-Crafts product was directly used for the oxime reaction without the need for column chromatography purification. The organic solvent was dichloromethane, and the volume was 1000 mL.

[0063] It is understood that in the embodiments of this application, ferric chloride is selected as a Lewis acid catalyst, and trifluoroacetyl chloride is used as an acylation reagent. With a molar ratio of 1:4.88:5.07 and a short reaction time of 5 hours at room temperature (20°C), highly selective complete substitution of bis(trifluoroacetyl) groups can be achieved within a short period at room temperature. This significantly shortens the reaction time, improves production efficiency, and verifies the wide temperature adaptability and high conversion efficiency of the Friedel-Crafts acylation reaction. At the same time, a simple post-treatment method of water quenching-liquid separation-distillation is adopted, which eliminates the need for column chromatography purification and allows the intermediate to be directly added to the next reaction step. This demonstrates the wide adaptability of this process to different Lewis acid catalysts and different reaction times, significantly improving the process tolerance. Furthermore, the generated dicarbonyl intermediate is stable and can stably adapt to the process requirements of subsequent oxime reactions.

[0064] Step 3: The Friedel-Crafts product was dissolved in acetonitrile solvent and oximated with hydroxylamine hydrochloride. The reaction temperature was controlled at 10℃ and the reaction time was 10h. After the reaction was completed, the bisoxime-substituted oxime product was obtained through post-treatment.

[0065] The amounts of the Friedel-Crafts product and hydroxylamine hydrochloride were 100g (0.2mol) and 138.9g (2.0mol), respectively, with a molar ratio of 1:10.

[0066] It should be noted that the organic solvent is acetonitrile, and the amount used is 500 mL. After the reaction is completed, the solvent is removed by distillation, and the crude product is added to 200 mL of process water for slurrying. After filtration, the bisoxime-substituted oxime product is obtained, which can be directly used for sulfonyl esterification reaction without the need for column chromatography purification.

[0067] It is understood that in this application embodiment, hydroxylamine hydrochloride is selected as the oxime reagent, and acetonitrile is used as the reaction solvent. With a molar ratio of 1:10 and reaction conditions of 10℃ and 10h, the complete oxime conversion of the dicarbonyl group can be achieved at a low temperature, effectively suppressing side reactions that may occur under high temperature conditions. This verifies the wide temperature adaptability of the oxime reaction, and the target conversion can be stably completed even at a low temperature of 10℃. At the same time, a simple post-treatment method of distillation to remove solvent and water slurry filtration is adopted, which can obtain a high-purity intermediate without the need for column chromatography purification and directly input into the next reaction. This proves the wide adaptability of this process to different reaction solvents and different reaction temperatures, further broadening the parameter adjustment window of the process. Moreover, the generated dioxime intermediate has a stable structure and can stably adapt to the process requirements of the subsequent sulfonyl esterification reaction.

[0068] Step 4: The oxime product is dissolved in acetonitrile solvent and sulfonated with propylsulfonyl chloride under the action of 4-dimethylaminopyridine (DMAP). The reaction temperature is controlled at 30℃ and the reaction time is 12h. After the raw material reaction is completed, the crude product is obtained by washing with water and distillation. The crude product is then purified by solvent recrystallization to obtain the target oxime ester photoacid-producing compound.

[0069] The amounts of the oxime product, propylsulfonyl chloride, and 4-dimethylaminopyridine (DMAP) were 100 g (0.2 mol), 285.2 g (2.0 mol), and 366 g (3.0 mol), respectively, with a molar ratio of 1:10:15.

[0070] It should be noted that the organic solvent is acetonitrile, and the amount used is 500 mL; after the reaction is complete, 100 mL of process water is added, the mixture is allowed to stand and separated, and the organic phase is evaporated to dryness to obtain the crude product; the solvent used for recrystallization purification is isopropanol, and the amount used is 500 mL of isopropanol per 100 g of crude product; the recrystallization process is as follows: the crude product is added to the purification solvent, heated to 80 °C and stirred until completely dissolved, then cooled to 0 °C, the precipitated solid is filtered and dried to obtain the target product.

[0071] It is understood that in the embodiments of this application, propyl sulfonyl chloride is selected as the sulfonating reagent, DMAP is used as a highly efficient catalyst and acid-binding agent, and acetonitrile is used as the reaction solvent. With a molar ratio of 1:10:15 and reaction conditions of 30℃ and 12h, the complete sulfonation conversion of the oxime group can be achieved under mild conditions of 30℃, which verifies the wide adaptability of the sulfonation reaction to different acid-binding agents, different reaction temperatures, and different solvent systems. The subsequent simple post-treatment of water washing and distillation, combined with the recrystallization purification process of isopropanol as a single solvent and low temperature crystallization at 0℃, does not require column chromatography purification to obtain high-purity target products, which proves the adaptability of this process to different purification systems. The NMR characterization confirms that the product structure is completely consistent with the design target. The process parameters have a wide window and strong tolerance, and can be flexibly adjusted according to the equipment conditions and raw material batches of industrial production, which has a strong industrial adaptability.

[0072] The target product in this embodiment is... 1 HNMR (400MHz, DMSO) characterization showed that the characteristic peaks were completely consistent with the target structure.

[0073] Comparative Example 1 This comparative example provides a method for synthesizing an oxime ester photoacid-producing compound, comprising: Step 1: Take 100g (1.06mol) phenol, 108g (0.53mol) 1,3-dibromopropane, and 125g (2.66mol) sodium carbonate in a molar ratio of 1:0.5:2.51, add them to 500mL acetonitrile and mix well. The etherification reaction is carried out at 60℃ for 6h. After the reaction is completed, add 200g of process water and extract with 200g of ethyl acetate. Remove the solvent by organic phase distillation. The crude product is purified by silica gel column chromatography with a 200-300 mesh filter. The eluent is a mixture of petroleum ether and ethyl acetate in a volume ratio of 10:1 to obtain the etherified product 1,3-diphenyloxypropane.

[0074] Step 2: Take 100g (0.44mol) of the above etherification product 1,3-diphenoxypropane, dissolve it in 1000mL of dichloromethane, add 240g (1.80mol) of aluminum trichloride in portions, and add 276g (1.31mol) of trifluoroacetic anhydride dropwise at 0~10℃ to carry out Friedel-Crafts acylation reaction. The molar ratio of the three is 1:4.09:2.98. During the dropwise addition, the system temperature is maintained at 0~10℃. After the dropwise addition is completed, the reaction is kept at this temperature for a total reaction time of 10h. After the reaction is completed, process water is added to quench the reaction, and the mixture is allowed to stand and separate. The solvent is removed by distillation of the organic phase. The crude product is purified by silica gel column chromatography with a 200-300 mesh filter. The eluent is a mixture of dichloromethane and petroleum ether at a volume ratio of 3:1 to obtain the bis(trifluoroacetyl) substituted Friedel-Crafts product, which is directly used for subsequent oxime reaction.

[0075] Step 3: Take 100g (0.24mol) of the above Friedel-Crafts product, dissolve it in 500mL of ethanol, add 66g (0.95mol) of hydroxylamine hydrochloride and mix well. The molar ratio of the two is 1:3.96. Carry out the oxime reaction at 40℃ for 10h. After the reaction is completed, remove the solvent by distillation. The crude product is purified by silica gel column chromatography with a 200-300 mesh. The eluent is a mixture of ethyl acetate and petroleum ether at a volume ratio of 1:2 to obtain the bisoxime-substituted oxime product, which can be directly used for the subsequent sulfonyl esterification reaction.

[0076] Step 4: Take 100g (0.22mol) of the above oxime product, dissolve it in 100mL of dichloromethane, add 348g (2.0mol) of N-propanesulfonyl imidazole and 67.4g (0.66mol) of triethylamine, mix well, and carry out the sulfonation reaction at 10℃ for 3h. After the reaction is complete, add 100mL of process water, let stand and separate the liquid, and evaporate the organic phase to obtain the crude product. The crude product is purified by 200-300 mesh silica gel column chromatography, using a mixture of methanol and dichloromethane at a volume ratio of 1:50 as the eluent to obtain the target oxime ester photoacid-producing compound.

[0077] The target product of this comparative example was... 1 HNMR (400MHz, DMSO) characterization showed that the characteristic peaks were consistent with the target structure.

[0078] Comparative Example 2 This comparative example provides a method for synthesizing an oxime ester photoacid-producing compound, comprising: Step 1: Take 100g (1.06mol) phenol, 21.2g (0.106mol) 1,3-dibromopropane, and 125g (2.66mol) sodium carbonate in a molar ratio of 1:0.1:2.51, add them to 500mL acetonitrile and mix well. Carry out the etherification reaction at 60℃ for 6h. After the reaction is completed, add 200g of process water and extract with 200g of ethyl acetate. Remove the solvent by organic phase distillation to obtain the etherified product 1,3-diphenoxypropane, which does not require column chromatography purification.

[0079] Step 2: Take 100g (0.44mol) of the above etherification product 1,3-diphenoxypropane, dissolve it in 1000mL of dichloromethane, add 240g (1.80mol) of aluminum trichloride in portions, and add 276g (1.31mol) of trifluoroacetic anhydride at 30℃ to carry out Friedel-Crafts acylation reaction. The molar ratio of the three is 1:4.09:2.98, and the total reaction time is 10h. After the reaction is completed, quench with process water, let stand and separate the liquid, and remove the solvent by distillation of the organic phase to obtain the bis(trifluoroacetyl) substituted Friedel-Crafts product, which can be directly used for subsequent oxime reaction without the need for column chromatography purification.

[0080] Step 3: Take 100g (0.24mol) of the above Friedel-Crafts product, dissolve it in 500mL of ethanol, add 16.7g (0.24mol) of hydroxylamine hydrochloride and mix well. The molar ratio of the two is 1:1. Carry out the oxime reaction at 80℃ for 10h. After the reaction is completed, distill to remove the solvent. Add 200mL of process water to the crude product and slurry it. After filtration, the bisoxime-substituted oxime product is obtained, which can be directly used for subsequent sulfonyl esterification reaction without the need for column chromatography purification.

[0081] Step 4: Take 100g (0.22mol) of the above oxime product, dissolve it in 100mL of dichloromethane, add 28.6g (0.22mol) of N-propanesulfonyl imidazole and 67.4g (0.66mol) of triethylamine, mix well, the molar ratio of the three is 1:1:3, and carry out sulfonation reaction at 10℃ for 3h. After the reaction is completed, add 100mL of process water, let stand and separate the liquid, and evaporate the organic phase to obtain the crude product. The crude product is purified by recrystallization from methanol. The amount of methanol used is 500mL of methanol per 100g of crude product. The specific process is as follows: add the crude product to methanol, heat to 65℃ and stir until completely dissolved, then cool to 20℃, precipitate the solid, filter and dry to obtain the target oxime ester photoacid-producing compound.

[0082] The target product of this comparative example was... 1 Characterization by HNMR (400MHz, DMSO) showed no obvious impurity peaks, and only the characteristic signal of the target product could be detected.

[0083] Performance testing The photolithographic performance of the oxime ester photoacid generators prepared in Examples 1 to 3 and Comparative Examples 1 to 2 was analyzed using the photoresist formulation verification method. I-line photoresist substrates with the same basic formulation were selected, and equal amounts of the photoacid generators prepared in Examples 1 to 3 and Comparative Examples 1 to 2 were added to prepare photoresist solutions. The solutions were uniformly spin-coated onto the surface of silicon wafers. After pre-baking, exposure, post-baking, and development, the photolithographic sensitivity, resolution, pattern linewidth roughness, and acid generation efficiency were tested. The performance test data are shown in Table 1.

[0084] Table 1. Performance test results of the lithography core.

[0085] As shown in Table 1, the oxime ester photoacid generators prepared in Examples 1 to 3 of this application significantly outperform Comparative Examples 1 to 2 in terms of photolithography core performance. This application constructs a highly symmetrical dioxime ester photoactive molecule through a four-step synergistic reaction involving etherification, Friedel-Crafts acylation, oximeation, and sulfonation. This molecule undergoes a directional cleavage reaction of the oxime ester bond under UV exposure, rapidly and efficiently releasing strong acid, providing a stable acid source for acid-catalyzed crosslinking of photoresist, with an acid generation efficiency of 92.5% to 93.8%. Simultaneously, the entire process employs a column-free chromatography technique to ensure high product purity, reducing the loss of photoresist by impurities, resulting in a photolithography sensitivity as low as 12.2 to 12.8 mJ / cm², a resolution of 0.10 to 0.11 μm, and a linewidth roughness controlled at 2.9 to 3.2 nm. Comparative Example 1 showed that the product structure was isomorphic due to column chromatography, and Comparative Example 2 showed that structural isomorphic impurities that overlapped with the target product's proton spectrum signal were generated due to parameter malfunction. Both of them had problems of low photolysis efficiency and deterioration of photolithography performance, and could not meet the requirements of high-precision photolithography.

[0086] The thermal stability of the oxime ester photoacid generators prepared in Examples 1 to 3 and Comparative Examples 1 to 2 was analyzed using thermal analysis and baking verification methods. The initial thermal decomposition temperature of the products was detected by thermogravimetric analyzer. At the same time, the photoresist pre-baking process was simulated, and the products were baked at 120 degrees Celsius for 2 minutes, 5 minutes and 10 minutes. The acid retention rate at different baking times was detected. The performance test data are shown in Table 2.

[0087] Table 2 Results of thermal stability test

[0088] As shown in Table 2, the oxime ester photoacid-producing agents prepared in Examples 1 to 3 of this application exhibit significantly better thermal stability than those in Comparative Examples 1 to 2. The symmetrical bisoxime ester molecules prepared in this application possess a stable conjugated structure, effectively suppressing thermal degradation and non-photolytic acid-producing side reactions at high temperatures. The initial thermal decomposition temperature reaches 178 to 181°C, and after holding at 120°C for 10 minutes in a photolithography baking process, the acid retention rate remains above 97%, perfectly matching the process windows for pre- and post-photolithography baking. Comparative Example 1 suffers from the introduction of thermosensitive isomeric impurities due to column chromatography, while Comparative Example 2 exhibits excessively high byproduct content, resulting in a significant decrease in molecular structural stability and a marked reduction in initial thermal decomposition temperature. Under high-temperature conditions, the acid is rapidly lost, easily leading to defects such as photolithographic pattern deformation and uneven development, failing to meet the thermal stability requirements of industrial photolithography production.

[0089] The stability of the oxime ester photoacid generators prepared in Examples 1 to 3 and Comparative Examples 1 to 2 was analyzed by long-term storage test. The samples were stored at room temperature (25 degrees Celsius) under light-proof and sealed conditions for 12 months. The retention rate of the effective component purity, appearance changes and photolithography sensitivity attenuation rate of the products were detected. The performance test data are shown in Table 3.

[0090] Table 3 Long-term storage stability test

[0091] As shown in Table 3, the oxime ester photoacid generators prepared in Examples 1 to 3 of this application exhibit excellent long-term storage stability. The recrystallization process of this application yields a regular and dense product crystal form. Combined with its high purity and impurity-free characteristics, it effectively blocks the oxidative degradation of the active ingredients by oxygen and moisture. After 12 months of sealed storage at room temperature, protected from light, the purity retention rate of the active ingredients exceeds 92%, the photolithography sensitivity attenuation rate is less than 4.5%, and there is no deterioration in appearance, meeting the requirements for long-term storage and transportation. In contrast, Comparative Examples 1 and 2, due to insufficient product purity and impaired molecular structure integrity, experienced continuous degradation of the active ingredients during storage, resulting in yellowing, clumping, and other deterioration phenomena. Irreversible degradation of photolithography performance occurred, failing to guarantee the performance consistency and application reliability of the products during long-term use.

[0092] The oxime ester photoacid generators prepared in Examples 1 to 3 and Comparative Examples 1 to 2 were analyzed for industrial production and environmental indicators using process parameter detection methods. The total molar yield based on phenol, total organic solvent recovery rate, comprehensive energy consumption per unit product, and production cycle per batch were tested. The performance test data are shown in Table 4.

[0093] Table 4 Test Results of Industrialized Production and Green Environmental Protection Indicators

[0094] As shown in Table 4, the oxime ester photoacid generators prepared in Examples 1 to 3 of this application exhibit outstanding industrial suitability and environmental performance. This application employs a simplified process without column chromatography, allowing intermediates to be directly used after extraction, distillation, and pulping, significantly shortening the production process. The total molar yield based on phenol reaches 66.8% to 68.2%, the organic solvent recovery rate exceeds 90%, the unit product energy consumption is as low as 118 kWh / t, and the shortest single-batch cycle is only 30 hours, making it suitable for continuous large-scale production. Comparative Example 1 uses multi-step column chromatography purification, resulting in a surge in solvent consumption, high energy consumption, and a cycle time as long as 96 hours; Comparative Example 2 suffers from uncontrolled process parameters, leading to extremely low raw material conversion rate and a total yield of only 11.3%. Both examples suffer from high production costs, poor environmental benefits, and inability to be scaled up.

[0095] To verify the structure and purity of the synthesized target product, systematic spectroscopic and purity analyses were performed on the samples prepared in Examples 1 to 3. Figure 2 The proton nuclear magnetic resonance spectrum of the target product prepared in Example 1 ( 1 ¹H NMR spectroscopy showed that all characteristic peaks were in perfect agreement with the structure of the target molecule 1,1'-[1,3-propanediylbis(oxy-4,1-phenylene)]bis[2,2,2-trifluoroethylone]1,1'-bis[O-(propylsulfonyl)oxime]; the products prepared in Examples 2 and 3 were subjected to parallel ¹H NMR spectroscopy, and their characteristic peaks were consistent with... Figure 2They are completely identical and match the target molecule structure. Figure 3 The image shows the liquid chromatography-mass spectrometry (LC-MS) chromatogram of the product prepared in Example 1. The high-performance liquid chromatogram of channel DAD1A, calculated using the area normalization method, shows a product purity of 98.2%. The products prepared in Examples 2 and 3, tested using the same detection method, showed purities of 97.8% and 97.5%, respectively. The purity of all three batches of products from these examples is higher than 97%. Furthermore, the characteristic mass spectrometric peak of channel MSD2 in this chromatogram perfectly matches the theoretical molecular weight of the target product. The UV spectrum of channel DAD1B and the extracted ion chromatogram of channel MSD1 further corroborate the correctness of the product structure and the reliability of the main peak purity. Figure 4 The mass spectrometry (MS) spectrum of the product prepared in Example 1 shows that its molecular ion peak perfectly matches the theoretically precise molecular weight of the target product, further confirming the molecular composition of the target product. Parallel mass spectrometry tests of the products prepared in Examples 2 and 3 also show that their characteristic molecular ion peaks match the theoretically precise molecular weight of the target product. Figure 4 Totally consistent. Figure 5 The NMR fluorine spectrum of the product prepared in Example 1 shows only a single characteristic peak corresponding to the trifluoromethyl group of the target molecule, with no interfering peaks, and perfectly matches the chemical environment of the fluorine atom in the target molecule. The products prepared in Examples 2 and 3 were tested in parallel using NMR fluorine spectra, and their characteristic peaks were consistent with... Figure 5 Totally consistent.

[0096] The above spectra and parallel test data jointly confirm that the products prepared in Examples 1-3 all possess correct chemical structures and high purity, providing a reliable structural and purity basis for the products' excellent photolithography performance, thermal stability, and storage stability. The products prepared in Comparative Examples 1 and 2, when analyzed in parallel using the same method, all showed obvious impurity peaks in their HPLC spectra. Comparative Example 1 showed impurity peaks other than the target product in its 1H NMR and fluorine spectra, while Comparative Example 2 showed no obvious impurity peaks in its 1H NMR, but non-target component signals were detected in its fluorine and mass spectra. This confirms that both comparative examples contain significant isomeric impurities or byproduct residues, with purity and structural integrity far lower than the examples, which is the core reason for the significant deterioration in their various application performances.

[0097] In summary, this application successfully prepared a structurally regular and high-performance oxime ester photoacid generator through precise synergistic control of four steps: etherification, Friedel-Crafts acylation, oximeization, and sulfonation, combined with a green purification process without column chromatography. The product significantly outperforms Comparative Example 1 and Comparative Example 2 in four dimensions: core photolithography performance, thermal stability, long-term storage stability, and industrial applicability. The 1H NMR, fluorine, mass spectrometry, and liquid chromatography of the target product prepared in Example 1 all confirmed that its structure was completely consistent with the design, without any isomeric impurities or byproduct interference. In photolithography applications, the product of this application, with its directional photolysis characteristics of symmetrical bisoxime esters, achieves efficient acid production and high-precision patterning, with performance far exceeding that of the comparative examples, which suffer from structural isomerism and impurity residues. Thermal stability and storage test results show that the symmetrical molecular structure and dense crystal form can effectively resist high-temperature degradation and environmental corrosion, maintaining stable performance under conventional photolithography processes and long-term storage conditions, completely solving the problems of thermal instability and storage degradation caused by impurities in the comparative examples. Further industrial and environmental testing has verified that the simplified process of this application can significantly improve raw material utilization and solvent recovery rates, reduce production energy consumption and cycle time, and overcome the bottlenecks of high cost and inability to scale up existing technologies due to reliance on column chromatography. Overall, the oxime ester photoacid generator prepared in this application simultaneously meets the stringent performance requirements of high-end i-line photoresists and the green and efficient needs of large-scale industrial production, fundamentally making up for the core shortcomings of traditional processes and possessing extremely high practical application value and industrial promotion prospects.

[0098] The method for synthesizing oxime ester photoacid-producing compounds according to the embodiments of this application involves a four-step continuous reaction process using phenol and 1,3-dihalopropane as starting materials. The process sequentially involves etherification, Friedel-Crafts acylation, oximation, and sulfonation to form a symmetrical dioxime ester target structure. Each step exhibits high selectivity and few side reactions. Simultaneously, key parameters such as molar ratio and temperature are precisely optimized for each step, and the raw material ratio and reaction conditions are rationally controlled to effectively improve reaction efficiency, raw material conversion rate, and para-substitution selectivity of the product, avoiding residual byproducts such as monoetherification and monooximation. The entire process requires no column chromatography purification; intermediates suitable for subsequent reactions can be obtained through simple operations such as extraction, washing, distillation, and pulping. Recrystallization purification using common industrial solvents such as methanol and ethanol can stably yield the target product with regular crystal form and a purity of not less than 97%, with good batch-to-batch quality reproducibility. This synthetic method boasts broad applicability to raw materials and flexible process adjustment, adaptable to various haloalkanes, bases, catalysts, and organic solvents. Process parameters can be flexibly adjusted according to raw material batches and equipment conditions. Furthermore, the entire reaction process operates under mild conditions, requiring no high-temperature, high-pressure, or highly corrosive reagents. Organic solvents can be distilled, recovered, and recycled. It results in low emissions, low energy consumption, and high safety, perfectly aligning with the principles of green chemistry and sustainable development. Thus, it solves the problems of complex processes, difficult purification, limited and costly raw materials, and difficulty in meeting the needs of industrial production inherent in traditional oxime ester photoacid-producing agent synthesis methods.

[0099] Although embodiments of this application have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and variations can be made to these embodiments without departing from the principles and spirit of this application, the scope of which is defined by the appended claims and their equivalents.

[0100] The present application and its embodiments have been described above. This description is not restrictive, and the actual application is not limited thereto. In conclusion, if a person skilled in the art is inspired by this description and designs a similar structure and embodiment without departing from the spirit of this application, such design should fall within the protection scope of this application.

Claims

1. A method for synthesizing an oxime ester photoacid-producing compound, characterized in that, include: Step 1: Using phenol and 1,3-dihalopropane as raw materials, an etherification reaction is carried out in an organic solvent under the action of alkali. The reaction temperature is controlled at 50~100℃. After the reaction is completed, the etherified product 1,3-diphenoxypropane is obtained through post-treatment. Step 2: Dissolve the etherified product 1,3-diphenoxypropane in an organic solvent, and add a trifluoroacetylation reagent at -20~20℃ under Lewis acid catalysis to carry out a Friedel-Crafts acylation reaction. After the reaction is completed, the product is quenched and post-treated to obtain the bistrifluoroacetyl-substituted Friedel-Crafts product. Step 3: Dissolve the Friedel-Crafts product in an organic solvent and carry out an oxime reaction with an oxime reagent. The reaction temperature is controlled at 10~60℃. After the reaction is completed, post-treatment is performed to obtain the bisoxime-substituted oxime product. Step 4: Dissolve the oxime product in an organic solvent and carry out a sulfonation reaction with a propyl sulfonating agent under the action of an alkali. The reaction temperature is controlled at -10~30℃. After the raw material reaction is completed, the crude product is obtained by washing with water and distillation. The crude product is then purified by solvent recrystallization to obtain the target oxime ester photoacid-producing compound.

2. The method for synthesizing oxime ester photoacid-producing compounds according to claim 1, characterized in that, In step one, the 1,3-dihalopropane is any one of 1,3-dibromopropane, 1,3-dichloropropane, or 1,3-diiodopropane; the molar ratio of phenol, 1,3-dihalopropane, and base is 1:0.4~2.5:2~5; the base is one or more of sodium carbonate, potassium carbonate, potassium phosphate, sodium bicarbonate, potassium bicarbonate, potassium hydroxide, sodium hydroxide, and triethylamine, and can be used in conjunction with 4-dimethylaminopyridine (DMAP) catalysis.

3. The method for synthesizing oxime ester photoacid-producing compounds according to claim 1, characterized in that, In step one, the organic solvent is one or more of toluene, methanol, acetonitrile, and N,N-dimethylformamide, which can be used in combination with water. After the reaction is completed, process water is added, and the mixture is extracted with ethyl acetate. The solvent is removed by organic phase distillation to obtain the 1,3-diphenoxypropane intermediate, which does not require column chromatography purification.

4. The method for synthesizing oxime ester photoacid-producing compounds according to claim 1, characterized in that, In step two, the Lewis acid is one or more of aluminum chloride, boron trifluoride, trimethylaluminum, ferrous chloride, copper chloride, zinc chloride, or ferric chloride; the trifluoroacetylation reagent is one or more of trifluoroacetyl chloride, S-trifluoroacetyl dibenzothiophenonium salt, or trifluoroacetic anhydride; and the molar ratio of the etherification product, Lewis acid, and trifluoroacetylation reagent is 1:2~5:2~8.

5. The method for synthesizing oxime ester photoacid-producing compounds according to claim 1, characterized in that, In step two, the trifluoroacetylation reagent is added dropwise, and the system temperature is maintained at -20~20℃ during the dropwise addition. After the dropwise addition is completed, the reaction is kept at this temperature until the raw material is completely converted. After the reaction is completed, process water is added to quench the reaction, and the mixture is allowed to stand and separate. The organic phase is distilled to remove the solvent. The obtained bis(trifluoroacetyl) substituted Friedel-Crafts product can be directly used for oxime reaction without the need for column chromatography purification. The organic solvent is one or more of toluene, acetonitrile, dichloromethane, and N,N-dimethylformamide.

6. The method for synthesizing oxime ester photoacid-producing compounds according to claim 1, characterized in that, In step three, the oxime reagent is one or more of hydroxylamine sulfate, hydroxylamine hydrochloride, hydroxylamine acetate, and 50% hydroxylamine aqueous solution; the molar ratio of the Friedel-Crafts product to the oxime reagent is 1:2 to 16; and the organic solvent is one or more of methanol, ethanol, water, dichloromethane, acetone, toluene, and acetonitrile.

7. The method for synthesizing oxime ester photoacid-producing compounds according to claim 1, characterized in that, In step three, after the reaction is complete, the solvent is removed by distillation, and the crude product is added to process water for pulping. After filtration, the bisoxime-substituted oxime product is obtained, which can be directly used for sulfonyl esterification reaction without the need for column chromatography purification.

8. The method for synthesizing oxime ester photoacid-producing compounds according to claim 1, characterized in that, In step four, the propylsulfonating agent is one or both of N-propanesulfonyl imidazole or propylsulfonyl chloride; the base is one or more of sodium carbonate, potassium carbonate, potassium phosphate, sodium bicarbonate, potassium bicarbonate, potassium hydroxide, sodium hydroxide, and triethylamine, which can be used in conjunction with 4-dimethylaminopyridine (DMAP) catalysis; the molar ratio of the oxime product, propylsulfonating agent, and base is 1:2~16:2~16; and the organic solvent is one or more of dichloromethane, acetone, tetrahydrofuran, methyl tert-butyl ether, and acetonitrile.

9. The method for synthesizing oxime ester photoacid-producing compounds according to claim 1, characterized in that, In step four, the solvent used for recrystallization purification is one or more of acetonitrile, methanol, toluene, ethanol, pure water, isopropanol, isopropyl ether, or n-heptane; the recrystallization process is as follows: the crude product is added to the purification solvent, heated to the reflux temperature and stirred until completely dissolved, then cooled to 0~20℃, the precipitated solid is filtered and dried to obtain the target product.

10. The method for synthesizing oxime ester photoacid-producing compounds according to claim 1, characterized in that, The target oxime ester photoacid-producing compound is 1,1'-[1,3-propanediylbis(oxo-4,1-phenylene)]bis[2,2,2-trifluoroethylone]1,1'-bis[O-(propylsulfonyl)oxime]; the synthesis method is a four-step reaction without column chromatography purification, and the product is subjected to... 1 HNMR characterization is consistent with the target structure.

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