Method for synthesizing pyroxasulfone

Abstract

The invention discloses a synthesis method of pyroxasulfone. The synthesis method comprises the following step: catalyzing # imgabs0 # by using oxidase as a catalyst to generate pyroxasulfone. According to the technical scheme, the thioether intermediate or the sulfoxide intermediate is oxidized by the oxidase to obtain the pyroxasulfone with higher conversion rate and yield, the synthesis method avoids the use of a strong oxidant and a toxic catalyst, and the potential safety hazard in the synthesis process of the pyroxasulfone is greatly reduced. The method provided by the invention has the advantages of stable process conditions, mild reaction conditions, simple operation and low pollution in the whole production process, and provides a new thought and method for artificially synthesizing the pyroxasulfone.

Description

Technical Field

[0001] The invention relates to the technical field of compound synthesis, and in particular to a method for synthesizing sulfonecarbazole. Background Art

[0002] Sulfonepyraclostrobin is a highly efficient and selective diacyl sulfide herbicide with good ability to control dicotyledonous weeds and grass weeds.

[0003] There are many existing synthetic routes for sulfonepyraclostrobin, but most of them require the synthesis of thioether intermediates, and finally oxidize the thioether to obtain the final product. Among them, the last step of oxidizing the thioether biosynthesis is mostly to oxidize the thioether under the condition of a catalyst using hydrogen peroxide to obtain sulfonepyraclostrobin. In this step, commonly used catalysts are sodium tungstate and acid (for example, CN111393427A, CN113831333A, CN 113754648 B).

[0004]

[0005] However, the oxidation of sulfide using strong oxidant hydrogen peroxide or in the presence of a catalyst has certain safety hazards and may cause environmental pollution. Therefore, it is of great significance to continue to find and develop new methods for synthesizing sulfonepyraclostrobin to reduce the production cost of sulfonepyraclostrobin, improve production efficiency, and realize industrialized production. Summary of the invention

[0006] The present invention aims to provide a method for synthesizing sulfone thiocarbamide to solve the technical problem of significant potential safety hazards in the synthesis process of sulfone thiocarbamide in the prior art.

[0007] In order to achieve the above object, according to one aspect of the present invention, a method for synthesizing sulfonepyraclostrobin is provided. The method comprises the following steps: using an oxidase as a catalyst to catalyze the This produces sulfonepyraclostrobin.

[0008] Further, the oxidase is Baeyer-Villiger monooxygenase.

[0009] Furthermore, monooxygenase is used as a catalyst to catalyze In the step of generating sulfonepyraclostrobin, the reaction conditions are: temperature 20-50°C, pH 6.5-9.5, The concentration is 0.01-1M.

[0010] Further, the reaction conditions are: temperature 25°C, pH 7.0, The concentration is 80mM.

[0011] Further, in the reaction system, the monooxygenase is monooxygenase ASYM-507026, ASYM-507002-V9, ASYM-507002-V10, ASYM-507004-V7, ASYM-507004-V12, ASYM-507004-V20, ASYM-507026-V6, ASYM-507026-V12, ASYM-507026-V13, ASYM-507026-V17, ASYM-507026-20, ASYM-507026-V21, ASYM-507026-V25 or ASYM-507026-V28.

[0012] Furthermore, in the reaction system, the amount of monooxygenase added is 2-20wt%, preferably 20wt.

[0013] Furthermore, the reaction system also includes ketoreductase, and the ketoreductase is ketoreductase ASYM-116511.

[0014] Furthermore, the amount of ketoreductase added is 0.05-4.0 wt%, preferably 0.5 wt%.

[0015] Furthermore, in the reaction system, NADP + and isopropanol, NADP + The amount of isopropanol used is 0.001-0.1wt, preferably 0.01wt; the amount of isopropanol used is 0.5-10eq, preferably 2eq.

[0016] According to another aspect of the present invention, there is provided a Baeyer-Villiger monooxygenase in catalysis Application in the production of sulfonepyraclostrobin.

[0017] By applying the technical solution of the present invention, a sulfide intermediate or a sulfoxide intermediate is oxidized by a monooxygenase to obtain sulfone thiocarbamide with a high conversion rate and yield. The synthesis method avoids the use of a strong oxidant and a toxic catalyst, and greatly reduces the potential safety hazard in the synthesis process of sulfone thiocarbamide. By adopting the method of the present invention, the process conditions are stable, the reaction conditions are mild, the operation is simple and the pollution is low in the whole production process, and a new idea and method is provided for the artificial synthesis of sulfone thiocarbamide. DETAILED DESCRIPTION

[0018] It should be noted that, in the absence of conflict, the embodiments and features in the embodiments of the present application can be combined with each other. The present invention will be described in detail below in conjunction with the embodiments.

[0019] In the prior art, the synthesis process of sulfone pyrazoline involves the use of strong oxidant hydrogen peroxide and a catalyst with certain toxicity for thioether oxidation, so there are certain safety hazards and may pollute the environment. In order to solve this technical problem, the inventor tried to use a bioenzymatic method to synthesize sulfone pyrazoline. In order to explore whether the enzymatic process is feasible, the inventor screened the existing enzyme library of Kailaiying Company, including 4-hydroxyacetophenone monooxygenase, cyclohexanone monooxygenase, phenylacetone monooxygenase, cycloalkanone monooxygenase, Baeyer-Villiger monooxygenase, nonspecific peroxygenase (UPO) and cytochrome P450 enzymes, and unexpectedly found that Baeyer-Villiger monooxygenase can catalyze This produces sulfonepyraclostrobin.

[0020] Based on this, this application proposes the following technical solutions.

[0021] According to a typical embodiment of the present application, a method for synthesizing sulfonepyraclostrobin is provided. The method comprises the following steps: using an oxidase as a catalyst to catalyze the This produces sulfonepyraclostrobin.

[0022] By applying the technical scheme of the present invention, oxidase is used to oxidize a thioether intermediate or a sulfoxide intermediate to obtain sulfone thiochloride with a high conversion rate and yield. The synthesis method avoids the use of strong oxidants and toxic catalysts, and greatly reduces the potential safety hazards in the synthesis process of sulfone thiochloride. The enzyme-catalyzed synthesis has mild reaction conditions, can effectively reduce energy consumption and the generation of by-products, is suitable for large-scale industrial production, especially in the synthesis of pesticides and medicines, can improve the purity and yield of the product, and reduce production costs.

[0023] Preferably, the oxidase is Baeyer-Villiger monooxygenase, and Baeyer-Villiger monooxygenase is used as a catalyst to catalyze In the step of generating sulfonepyraclostrobin, the reaction conditions are: temperature 20-50°C, pH 6.5-9.5, The concentration is 0.1-1M; the reaction conditions are more preferably: temperature 25°C, pH 7.0, The concentration is 80 mM. Under these reaction conditions, the conversion rate, selectivity and yield of the reaction are all optimal, and sulfonepyraclostrobin can be efficiently synthesized, which is suitable for industrial production.

[0024] In a preferred embodiment of the present application, in the reaction system, the oxidase is a monooxygenase ASYM-507026, ASYM-507002-V9, ASYM-507002-V10, ASYM-507004-V7, ASYM-507004-V12, ASYM-507004-V20, ASYM-507026-V6, ASYM-507026-V12, ASYM-507026-V13, ASYM-507026-V17, ASYM-507026-20, ASYM-507026-V21, ASYM-507026-V25 or ASYM-507026-V28 (the above monooxygenases are all commercially available enzymes of Tianjin Kailaiying Biotechnology Co., Ltd.). These enzymes have the advantage of high conversion rate in the synthesis of sulfonepyraclostrobin, and industrial production can be carried out with less enzyme, and the production cost can be effectively controlled. For example, the addition amount of monooxygenase is 2-20wt%, preferably 20wt.

[0025] In a preferred embodiment of the present application, the reaction system further includes ketoreductase, which is ASYM-116511. Preferably, the amount of ketoreductase added is 0.05-4.0wt%, preferably 0.5wt. By adjusting the amount of ketoreductase, the electron donor and acceptor in the reaction system can be balanced, the conversion rate and selectivity of the reaction can be improved, and it is suitable for industrial production, especially in enzyme-catalyzed reactions that require fine control of reaction conditions.

[0026] Preferably, the reaction system also includes NADP + , NADP + The dosage is 0.001-0.1wt%, preferably 0.01wt. + As an electron acceptor, the adjustment of its dosage can balance the electron flow in the reaction system, improve the conversion rate and selectivity of the reaction, and is suitable for industrial production.

[0027] Isopropanol is used as a solvent and reaction medium, and the adjustment of its dosage can optimize the reaction environment and improve the conversion rate and selectivity of the reaction. In a preferred embodiment of the present application, the reaction system also includes isopropanol, and the dosage of isopropanol is 0.5-10eq; preferably 2eq.

[0028] According to a typical embodiment of the present application, a Baeyer-Villiger monooxygenase is provided in catalysis Application of Baeyer-Villiger monooxygenase in the production of sulfone metabendazole. The sulfone metachloride can be produced with high optical purity (eg, 100%) and yield (eg, 84.4% and 86.6%, respectively).

[0029] In one embodiment of the present application, a method for synthesizing sulfone thiocarbamide is provided. The method comprises the following steps: preparing a thioether intermediate compound or sulfoxide intermediate As raw materials, enzymatic reaction is carried out under constant temperature conditions with oxidase, coenzyme factor, buffer, coenzyme cycle, reductase to obtain sulfone pyraclostrobin. Targeting the thioether intermediate substrate, hundreds of oxidases in the Kalein enzyme library were screened, and a Baeyer-Villiger monooxygenase (BVMO) ASYM-507026-V13 was found to achieve a satisfactory conversion rate in the synthesis of sulfone pyraclostrobin.

[0030] The beneficial effects of the present application will be further described below with reference to embodiments.

[0031] The substrates in the following examples of this application are all thioether intermediates or sulfoxide intermediate

[0032]

[0033] Example 1

[0034] Screening of oxidases

[0035] Oxidase that can synthesize sulfonepyraclostrobin has not been reported in the prior art, and the inventors tried to use a bioenzymatic method to synthesize sulfonepyraclostrobin. In order to explore whether the enzymatic process is feasible, the inventors screened the existing enzyme library of Kailaiying Company, including 4-hydroxyacetophenone monooxygenase, cyclohexanone monooxygenase, phenylacetone monooxygenase, cycloalkanone monooxygenase, Baeyer-Villiger monooxygenase, nonspecific peroxygenase (UPO), and cytochrome P450 enzymes, etc. Hundreds of oxidases, most of the enzymes showed no activity (HPLC detected no product generation, the specific results are not shown), but there are also a few enzymes with a certain catalytic thioether intermediate conversion to sulfonepyraclostrobin activity.

[0036] In this example, hundreds of oxidases in the enzyme library of Asymchem were selected for enzyme screening of thioether intermediates and sulfoxide intermediates. The screening system was as follows: 10 mM substrate, 4 wt ketoreductase ASYM-116511 crude enzyme solution (1 g / mL), 20 wt oxidase crude enzyme solution (1 g / mL), 0.1 wt NADP + , 0.1wt NAD + , 10eq isopropanol, 100mM PB 7.5, 30℃ for 20h. After the reaction, the conversion rate was detected by HPLC. The results showed that most enzymes in the enzyme library could not generate products on HPLC, but a few enzymes generated products, with the highest conversion rate of about 50%.

[0037] Table 1

[0038]

[0039]

[0040]

[0041]

[0042] Note: In Table 1 above, * represents a conversion rate less than 1%, ** represents a conversion rate greater than or equal to 1% and less than 10%, *** represents a conversion rate greater than or equal to 10% and less than 30%, **** represents a conversion rate greater than or equal to 30% and less than 50%, and ***** represents a conversion rate greater than or equal to 50%.

[0043] Among them, NO.4 in Table 1 is phenylacetone monooxygenase, NO.13 is cycloalkanone monooxygenase, NO.14-15 are mutants of 4-hydroxyacetophenone monooxygenase, NO.16-18 are cyclohexanone monooxygenase, NO.27-28 are nonspecific peroxygenases, NO.29-31 are cytochrome P450 enzymes, and the other numbers are all Baeyer-Villiger monooxygenases.

[0044] Example 2

[0045] Different reaction systems

[0046] ASYM-507026-V13, which has good activity on thioether intermediate substrates and sulfoxide intermediates, was selected for enzyme catalysis processes in different reaction systems, as shown below:

[0047] Reaction system 1: 10mM substrate, 4wt ketoreductase ASYM-116511 crude enzyme solution (1g / mL), 20wt monooxygenase ASYM-507026-V13 crude enzyme solution (1g / mL), 0.1wt NADP + , 0.1wt NAD + , 10eq isopropanol, 100mM PB 7.5, 30°C for 20h. After the reaction, the conversion rate was detected by HPLC.

[0048] Reaction system 2: 10 mM substrate, 4 wt ketoreductase ASYM-116511 crude enzyme solution (1 g / mL), 20 wt monooxygenase ASYM-507026-V13 crude enzyme solution (1 g / mL), 0.1 wt NADP + , 0.1wt NAD +, 10 eq isopropanol, 10 eq hydrogen peroxide solution (20% content), 10 wt catalase (1 g / mL), 100 mM PB 7.5, react at 30° C. for 20 h. After the reaction is completed, the conversion rate is detected by HPLC.

[0049] Reaction system 3: 10mM substrate, 20wt monooxygenase ASYM-507026-V13 crude enzyme solution (1g / mL), 4wt glucose dehydrogenase (GDH) crude enzyme solution (1g / mL), 0.1wt NADP + , 0.1wt NAD + , 5eq glucose monohydrate, 100mM PB7.5, 30°C for 20h. After the reaction, the conversion rate was detected by HPLC.

[0050] Reaction system 4: 10 mM substrate, 4 wt formate dehydrogenase crude enzyme solution (1 g / mL), 20 wt monooxygenase ASYM-507026-V13 crude enzyme solution (1 g / mL), 0.1 wt NADP + , 0.1wt NAD + , 5eq ammonium formate, 100mM PB 7.5, 30°C for 20h. After the reaction, the conversion rate was detected by HPLC.

[0051] Table 2

[0052]

[0053]

[0054] Note: In Table 2 above, - represents a decrease in conversion rate, and -+ represents an unchanged conversion rate.

[0055] Example 3

[0056] Optimization of reaction conditions

[0057] The reaction of system 1 was optimized by setting different temperatures, pH, substrate concentrations, reductase ASYM-116511 dosages, NAD + Dosage, NADP + Single factor optimization experiment of dosage and isopropanol dosage.

[0058] Reaction condition 1 (temperature optimization): 10 mM substrate, 4 wt ketoreductase ASYM-116511 crude enzyme solution (1 g / mL), 20 wt monooxygenase crude ASYM-507026-V13 enzyme solution (1 g / mL), 0.1 wt NADP + , 0.1wt NAD +, 10eq isopropanol, 100mM Pb 7.5, react at 20°C, 25°C, 30°C, 35°C, 40°C, 45°C and 50°C for 18h. After the reaction, the conversion rate was detected by HPLC.

[0059] Table 3

[0060]

[0061]

[0062] Note: In the above table, - represents a decrease in conversion rate, + represents an increase in conversion rate, and -+ represents an unchanged conversion rate.

[0063] Reaction condition 2 (pH optimization): 10 mM substrate, 4 wt ketoreductase ASYM-116511 crude enzyme solution (1 g / mL), 20 wt monooxygenase ASYM-507026-V13 crude enzyme solution (1 g / mL), 0.1 wt NADP + , 0.1wt NAD + , 10eq isopropanol, 100mM phosphate buffer with different pH values ​​were set, and the reaction was carried out at 25°C for 18h. After the reaction was completed, the conversion rate was detected by HPLC.

[0064] Table 4

[0065]

[0066] Note: In the above table, - represents a decrease in conversion rate, + represents an increase in conversion rate, and -+ represents an unchanged conversion rate.

[0067] Reaction condition 3 (substrate concentration optimization): different amounts of thioether intermediate or sulfoxide intermediate substrate, 4wt ketoreductase ASYM-116511 enzyme solution (1g / mL), 20wt monooxygenase ASYM-507026-V13 crude enzyme solution (1g / mL), 0.1wt NADP + , 0.1wt NAD + , 10 eq isopropanol, 100 mM PB 7.0, react at 25° C. for 18 h. After the reaction, the conversion rate was detected by HPLC.

[0068] Table 5

[0069]

[0070] Note: In the above table, - represents a decrease in conversion rate, and -+ represents an unchanged conversion rate.

[0071] Reaction condition 4 (optimized dosage of reductase 116511): 80 mM substrate, different dosages of crude enzyme solution of ketoreductase ASYM-116511 (1 g / mL), 20 wt crude enzyme solution of monooxygenase ASYM-507026-V13 (1 g / mL), 0.1 wt NADP + , 0.1wt NAD + , 10 eq isopropanol, 100 mM PB 7.0, react at 25° C. for 18 h. After the reaction, the conversion rate was detected by HPLC.

[0072] Table 6

[0073]

[0074]

[0075] Note: In the above table, - represents a decrease in conversion rate, and -+ represents an unchanged conversion rate.

[0076] Reaction condition 5 (ASYM-507026-V13 dosage optimization): 80 mM substrate, 0.5 wt ketoreductase ASYM-116511 crude enzyme solution (1 g / mL), different amounts of ASYM-507026-V13 crude enzyme solution (1 g / mL), 0.1 wt NADP + , 0.1wt NAD + , 10 eq isopropanol, 100 mM PB 7.0, react at 25° C. for 18 h. After the reaction, the conversion rate was detected by HPLC.

[0077] Table 7

[0078]

[0079] Note: In the above table, - represents a decrease in conversion rate, and -+ represents an unchanged conversion rate.

[0080] Reaction conditions 6 (NAD + and NADP + Selection): 80mM substrate, 0.5wt ketoreductase ASYM-116511 crude enzyme solution (1g / mL), 20wt monooxygenase ASYM-507026-V13 crude enzyme solution (1g / mL), explore only adding 0.1wt NADP + or 0.1wt NAD + Effect on the reaction, 10eq isopropanol, 100mM PB 7.0, reaction at 25°C for 18h. After the reaction, the conversion rate was detected by HPLC.

[0081] Table 8

[0082]

[0083] Note: In the above table, -+ means the conversion rate remains unchanged.

[0084] Reaction conditions 7 (NADP + Optimization of dosage): 80 mM substrate, 0.5 wt ketoreductase ASYM-116511 crude enzyme solution (1 g / mL), 20 wt monooxygenase ASYM-507026-V13 crude enzyme solution (1 g / mL), different dosages of NADP + , 10 eq isopropanol, 100 mM PB 7.0, react at 25° C. for 18 h. After the reaction, the conversion rate was detected by HPLC.

[0085] Table 9

[0086]

[0087] Note: In the above table, - represents a decrease in conversion rate, and -+ represents an unchanged conversion rate.

[0088] Reaction condition 8 (optimization of isopropanol dosage): 80 mM substrate, 0.5 wt ketoreductase ASYM-116511 crude enzyme solution (1 g / mL), 20 wt monooxygenase ASYM-507026-V13 crude enzyme solution (1 g / mL), 0.01 wt NADP + , different amounts of isopropanol, 100 mM PB 7.0, and reacted at 25°C for 18 h. After the reaction, the conversion rate was detected by HPLC.

[0089] Table 10

[0090]

[0091] Note: In the above table, - represents a decrease in conversion rate, and -+ represents an unchanged conversion rate.

[0092] Process Validation:

[0093] (1) Feeding: Add 100 mM PB buffer with a pH value of 7.0 to a 250 mL four-necked round-bottom bottle, and then add 0.01 wt NADP + , 2eq isopropanol, 0.5wt ketoreductase ASYM-116511 crude enzyme solution (1g / mL), 20wt monooxygenase ASYM-507026-V13 crude enzyme solution (1g / mL), slowly add 2g main raw material (sulfide intermediate or sulfoxide intermediate ). The mixture was heated to 25-30°C, stirred with a stirring paddle at 200 rpm, and reacted under the conditions of a ventilation rate of 50 mL / min. The system was tracked after 22 hours of reaction, and the reaction of the raw materials was completed after 89 hours. The mixture was cooled to room temperature, and concentrated hydrochloric acid was slowly added dropwise to a four-necked flask until pH 1 was reached to terminate the reaction. 2 wt diatomaceous earth was added to the system, and the mixture was cooled to 0-5°C, stirred for 1 hour, and filtered. The filter cake was washed with 40 mL of dichloromethane for 3 times, and each time the mixture was stirred for 0.5 hours and filtered, and the organic phases were combined and dried.

[0094] Finally, the reaction system with the thioether intermediate as the substrate obtained 1.9 g of white solid, namely sulfonepyraclostrobin. The optical purity of the solid was 100% as determined by HPLC, the content was 96.8%, and the yield was 84.4%.

[0095] The reaction system using the sulfoxide intermediate as the substrate obtained 1.9 g of white solid, namely sulfonepyraclostrobin. The optical purity of the solid was 100% as determined by HPLC, the content was 95.4%, and the yield was 86.6%.

[0096] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A method for synthesizing sulfonepyraclostrobin, characterized in that: The following steps are involved: Using oxidase as catalyst This produces sulfonepyraclostrobin.

2. The synthesis method according to claim 1, characterized in that The oxidase is Baeyer-Villiger monooxygenase.

3. The synthesis method according to claim 2, characterized in that The monooxygenase is used as a catalyst to catalyze In the step of generating sulfonepyraclostrobin, the reaction conditions are: temperature of 20-50°C, pH of 6.5-9.5, The concentration is 0.01-1M.

4. The synthesis method according to claim 3, characterized in that Preferably, the reaction conditions are: temperature 25°C, pH 7.0, The concentration is 80mM.

5. The synthesis method according to claim 1, characterized in that In the reaction system, the oxidase is monooxygenase ASYM-507026, ASYM-507002-V9, ASYM-507002-V10, ASYM-507004-V7, ASYM-507004-V12, ASYM-507004-V20, ASYM-507026-V6, ASYM-507026-V12, ASYM-507026-V13, ASYM-507026-V17, ASYM-507026-20, ASYM-507026-V21, ASYM-507026-V25 or ASYM-507026-V28.

6. The synthesis method according to any one of claims 1 to 5, characterized in that In the reaction system, the added amount of the oxidase is 2-20wt, preferably 20wt.

7. The synthesis method according to any one of claims 1 to 5, characterized in that The reaction system also includes ketoreductase, and the ketoreductase is ketoreductase ASYM-116511.

8. The synthesis method according to claim 7, characterized in that The added amount of the ketoreductase is 0.05-4.0wt.

9. The synthesis method according to claim 8, characterized in that The added amount of the reductase is 0.5wt.

10. The synthesis method according to any one of claims 1 to 5, characterized in that In the reaction system, NADP is also included + and isopropanol, the NADP + The dosage of isopropanol is 0.5-10eq. 11.Baeyer-Villiger monooxygenase catalyzes Application in the production of sulfonepyraclostrobin.

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