Preparation method of pyroxasulfone intermediate

Abstract

The invention relates to the technical field of synthesis of pesticide intermediates, in particular to a preparation method of a pyroxasulfone intermediate, which comprises the following steps: controlling the temperature, dropwise adding a methylhydrazine aqueous solution into ethyl trifluoroacetoacetate, and carrying out heat preservation for cyclization reaction; an acidic reagent is added for an acidolysis reaction, and 5-hydroxy-1-methyl-3-trifluoromethyl-1H-pyrazole is obtained; the preparation method comprises the following steps: carrying out salt forming reaction on 5-hydroxy-1-methyl-3-trifluoromethyl-1H-pyrazole and an alkaline reagent in an organic solvent; controlling the temperature, introducing difluorochloromethane, and carrying out a difluoromethylation reaction, so as to obtain 5-difluoromethoxy-1-methyl-3-trifluoromethyl-1H-pyrazole; 5-difluoromethoxy-1-methyl-3-trifluoromethyl-1H-pyrazole and sodium methanesulfonate are dissolved in a solvent, a coupling reaction is performed under the action of illumination and a catalyst to obtain the pyroxasulfone intermediate, the raw materials are cheap and easy to obtain, the steps are simple, and the method is suitable for industrialization.

Description

Technical Field

[0001] The invention relates to the technical field of pesticide intermediate synthesis, and in particular to a method for preparing a sulfonepyraclostrobin intermediate. Background Art

[0002] Sulfonepyrazoline is an isoxazole herbicide developed by Kumihiko Chemical Co., Ltd. of Japan. In the synthesis of sulfonepyrazoline, the introduction of the sulfone group can be achieved by either sulfide oxidation or by directly introducing a sulfonic acid group on the pyrazole ring. Compared with the former, there are fewer reports on the latter. Synthetic Chemistry, 2024, 32(9)833-839 reported a method for preparing a sulfonepyrazoline intermediate, which uses the sulfonepyrazoline intermediate CDTP (4-chloromethyl-5-difluoromethoxy-1-methyl-3-trifluoromethyl-1H-pyrazole) as a raw material, and the intermediate is prepared by condensation, alkaline hydrolysis, and oxidation. The raw material CDTP is expensive and not easy to obtain, and the yield of this route is relatively low at 76.9%. A Chinese patent application (publication number CN 118420608 A) discloses a process using ethyl trifluoroacetoacetate as a starting material, undergoing cyclization and difluoromethylation to produce Compound II, which is then reacted with formaldehyde or paraformaldehyde and sodium bisulfite to produce an intermediate. During the synthesis process, toxic formaldehyde gas is released, polluting the environment. A Chinese patent application (publication number CN117263925 A) discloses a process using Compound I as a starting material, undergoing hydroxymethylation to produce hydroxypyrazole methanol, which is then reacted with sodium bisulfite to produce hydroxypyrazole methanesulfonic acid sodium salt, which is then reacted with difluorochloromethane to produce the sulfonepyrazol intermediate. This route also requires formaldehyde for the hydroxymethylation reaction and is cumbersome. Summary of the Invention

[0003] In order to solve the above problems, the present invention provides a method for preparing a sulfonepyraclostrobin intermediate. The method uses ethyl trifluoroacetoacetate as a raw material, and prepares compound II through cyclization and difluoromethylation. Compound II is then reacted with sodium methanesulfonate in the presence of a catalyst to directly prepare the intermediate. The raw materials are cheap and easily available, the steps are simple, and the method is suitable for industrialization.

[0004] The invention provides a preparation method of a sulfonepyrazoline intermediate. The method comprises the following steps: controlling the temperature, dropwise adding a methylhydrazine aqueous solution into ethyl trifluoroacetoacetate, and keeping the temperature to carry out a cyclization reaction; adding an acidic reagent to carry out an acidolysis reaction to obtain 5-hydroxy-1-methyl-3-trifluoromethyl-1H-pyrazole; carrying out a salt-forming reaction between 5-hydroxy-1-methyl-3-trifluoromethyl-1H-pyrazole and an alkaline reagent in an organic solvent; controlling the temperature, introducing difluorochloromethane to carry out a difluoromethylation reaction to obtain 5-difluoromethoxy-1-methyl-3-trifluoromethyl-1H-pyrazole (Compound II); and dissolving 5-difluoromethoxy-1-methyl-3-trifluoromethyl-1H-pyrazole and sodium methanesulfonate in a solvent, and carrying out a coupling reaction under light irradiation and the action of a catalyst to obtain the sulfonepyrazoline intermediate.

[0005] In one embodiment, the preparation method of the sulfonepyraclostrobin intermediate comprises the following steps:

[0006] (1) controlling the temperature, adding a methylhydrazine aqueous solution dropwise to ethyl trifluoroacetoacetate, and keeping the temperature to perform a cyclization reaction; adding an acidic reagent to perform an acidolysis reaction, and adding water after the reaction is completed, cooling, and filtering to obtain 5-hydroxy-1-methyl-3-trifluoromethyl-1H-pyrazole;

[0007] (2) reacting 5-hydroxy-1-methyl-3-trifluoromethyl-1H-pyrazole with an alkaline reagent in an organic solvent to form a salt; controlling the temperature and introducing difluorochloromethane to carry out a difluoromethylation reaction; after the reaction, adding water, washing and separating the layers; desolventizing and distilling the organic layer to obtain 5-difluoromethoxy-1-methyl-3-trifluoromethyl-1H-pyrazole;

[0008] (3) 5-difluoromethoxy-1-methyl-3-trifluoromethyl-1H-pyrazole and sodium methanesulfonate are dissolved in a solvent, and a coupling reaction is carried out under the action of light and a catalyst. After the reaction, the temperature is lowered to 20-30° C., and a 5 wt % aqueous hydrochloric acid solution is added to adjust the pH to 2-3. The layers are filtered and separated, and the aqueous layer is desolvated under negative pressure to obtain a sulfonepyrazoline intermediate.

[0009] The present invention optimizes the preparation route of the sulfonepyrazoline intermediate, including the steps of preparing 5-hydroxy-1-methyl-3-trifluoromethyl-1H-pyrazole, 5-difluoromethoxy-1-methyl-3-trifluoromethyl-1H-pyrazole and the sulfonepyrazoline intermediate. Raw materials are readily available, the reaction steps are short, the operation is simple, the cost is low, the yield is high, and large-scale industrial production is easy to achieve.

[0010] In one embodiment, the cyclization reaction is carried out at a temperature of 0 to 25° C. and for a time of 20 to 40 minutes.

[0011] In one embodiment, the cyclization reaction is carried out at a temperature of 5 to 20° C. and for 30 minutes.

[0012] In one embodiment, the acid hydrolysis reaction is carried out at a temperature of 40 to 75° C. and for a time of 1.5 to 2.5 hours.

[0013] In one embodiment, the acid hydrolysis reaction is carried out at a temperature of 45 to 70° C. and for 2 hours.

[0014] In one embodiment, the mass proportion of methylhydrazine in the methylhydrazine aqueous solution is 30-50%.

[0015] In one embodiment, the mass proportion of methylhydrazine in the methylhydrazine aqueous solution is 40%.

[0016] In one embodiment, the acidic reagent is at least one of hydrochloric acid, sulfuric acid, nitric acid, acetic acid or formic acid.

[0017] In one embodiment, the acidic reagent is concentrated hydrochloric acid or acetic acid.

[0018] In one embodiment, the molar ratio of ethyl trifluoroacetoacetate, methylhydrazine, and acidic reagent is 1:(0.95-1.2):(0.05-0.3).

[0019] In one embodiment, the molar ratio of ethyl trifluoroacetoacetate, methylhydrazine, and acidic reagent is 1:(1-1.185):(0.111-0.185).

[0020] In one embodiment, the purity of the 5-hydroxy-1-methyl-3-trifluoromethyl-1H-pyrazole is ≥96 wt %, and the yield is ≥87%.

[0021] Specifically, the present invention optimizes the molar ratio of a methylhydrazine aqueous solution, ethyl trifluoroacetoacetate, and a preferred acidic reagent, and controls the cyclization reaction conditions and the acidolysis reaction conditions to ensure that the obtained 5-hydroxy-1-methyl-3-trifluoromethyl-1H-pyrazole has a purity of ≥96wt% and a yield of ≥87%, thereby meeting the requirements of subsequent preparation processes.

[0022] In one embodiment, the alkaline agent is at least one of sodium hydroxide, sodium ethoxide, sodium methoxide, potassium hydroxide, potassium tert-butoxide or potassium methoxide.

[0023] In one embodiment, the alkaline agent is sodium hydroxide or potassium hydroxide.

[0024] In one embodiment, the organic solvent is at least one of tetrahydrofuran, N,N-dimethylformamide, N,N-dimethylacetamide, 2-methyltetrahydrofuran, 1,4-dioxane, acetonitrile or toluene.

[0025] In one embodiment, the organic solvent is one of tetrahydrofuran, acetonitrile or 2-methyltetrahydrofuran.

[0026] In one embodiment, the temperature of the salt-forming reaction is 30-80° C., and the time is 0.8-1.5 h.

[0027] In one embodiment, the temperature of the salt-forming reaction is 40-60° C., and the time is 1 hour.

[0028] In one embodiment, the difluoromethylation reaction temperature is 40-90° C., and the reaction time is 0.8-1.5 h.

[0029] In one embodiment, the difluoromethylation reaction temperature is 50-70° C. and the reaction time is 1 h.

[0030] In one embodiment, the molar ratio of the 5-hydroxy-1-methyl-3-trifluoromethyl-1H-pyrazole, the alkaline reagent, and difluorochloromethane is 1:(1-3.5):(0.9-2.5).

[0031] In one embodiment, the molar ratio of the 5-hydroxy-1-methyl-3-trifluoromethyl-1H-pyrazole, the alkaline reagent, and difluorochloromethane is 1:(1.75-2.61):(1-1.26).

[0032] In one embodiment, the mass ratio of the 5-hydroxy-1-methyl-3-trifluoromethyl-1H-pyrazole to the solvent is 1:(3-6).

[0033] In one embodiment, the mass ratio of the 5-hydroxy-1-methyl-3-trifluoromethyl-1H-pyrazole to the solvent is 1:(3.94-3.98).

[0034] In one embodiment, the purity of the 5-difluoromethoxy-1-methyl-3-trifluoromethyl-1H-pyrazole is ≥97 wt %, and the yield is ≥97%.

[0035] Furthermore, by comprehensively controlling the conditions of the salt-forming reaction and the difluoromethylation reaction, using sodium hydroxide or potassium hydroxide as the alkaline reagent and tetrahydrofuran, acetonitrile or 2-methyltetrahydrofuran as the organic solvent, the purity of the prepared 5-difluoromethoxy-1-methyl-3-trifluoromethyl-1H-pyrazole is ensured to be ≥97wt% and the yield is ≥97%.

[0036] In one embodiment, the coupling reaction is carried out at a temperature of 20 to 80° C. and for a time of 4 to 7 hours.

[0037] In one embodiment, the coupling reaction temperature is 40-60° C., and the time is 5-6 hours.

[0038] In one embodiment, the molar ratio of the 5-difluoromethoxy-1-methyl-3-trifluoromethyl-1H-pyrazole, sodium methanesulfonate, and catalyst is 1:(0.85-2):(0.015-0.3).

[0039] In one embodiment, the molar ratio of 5-difluoromethoxy-1-methyl-3-trifluoromethyl-1H-pyrazole, sodium methanesulfonate, and catalyst is 1:(1-1.26):(0.019-0.103).

[0040] In one embodiment, the mass ratio of the 5-difluoromethoxy-1-methyl-3-trifluoromethyl-1H-pyrazole to the solvent is 1:(2-5).

[0041] In one embodiment, the mass ratio of the 5-difluoromethoxy-1-methyl-3-trifluoromethyl-1H-pyrazole to the solvent is 1:(2.94-3).

[0042] In one embodiment, the solvent is at least one of 2-methyltetrahydrofuran, tetrahydrofuran, dichloromethane, dichloroethane, cyclohexane or methylcyclohexane.

[0043] In one embodiment, the solvent is one of 2-methyltetrahydrofuran, tetrahydrofuran or dichloroethane.

[0044] In one embodiment, the catalyst is at least one of CuBr2, Cu(OAc)2, CuCl, Cu(OTf)2, FeCl2, Nd(OTf)3, CsOAc, Pd(PPh3)4, Ru(bpy)3Cl2, or Ce(NH4)4(SO4)4.

[0045] In one embodiment, the catalyst is one of Cu(OTf)2, Nd(OTf)3, CsOAc, Pd(PPh3)4, Ru(bpy)3Cl2 or Ce(NH4)4(SO4)4.

[0046] In one embodiment, the catalyst is one of Cu(OTf)2, Pd(PPh3)4 or Ce(NH4)4(SO4)4.

[0047] In one embodiment, the purity of the sulfonepyraclostrobin intermediate (5-difluoromethoxy-1-methyl-3-trifluoromethyl-1H-pyrazole-4-methanesulfonic acid) is ≥95 wt %, and the yield is ≥93%.

[0048] Furthermore, by controlling the molar ratio of 5-difluoromethoxy-1-methyl-3-trifluoromethyl-1H-pyrazole, sodium methanesulfonate, and the catalyst, especially by using one of Cu(OTf)2, Pd(PPh3)4, or Ce(NH4)4(SO4)4 as a catalyst, a low-temperature reaction can be achieved while the purity of the product is ≥95wt% and the yield is ≥93%.

[0049] Beneficial effects

[0050] 1. The present invention provides a method for preparing a sulfonepyraclostrobin intermediate. The method uses ethyl trifluoroacetoacetate as a raw material, and prepares compound II through cyclization and difluoromethylation. Compound II is then reacted with sodium methanesulfonate in the presence of a catalyst to directly prepare the intermediate. The raw materials are cheap and easily available, the steps are simple, and the method is suitable for industrialization.

[0051] 2. The present invention optimizes the preparation route of the sulfonepyraclostrobin intermediate, including the preparation steps of 5-hydroxy-1-methyl-3-trifluoromethyl-1H-pyrazole, 5-difluoromethoxy-1-methyl-3-trifluoromethyl-1H-pyrazole and the sulfonepyraclostrobin intermediate. The raw materials are easily available, the reaction steps are short, the operation is simple, the cost is low, the yield is high, and it is easy to realize large-scale industrial production.

[0052] 3. The present invention optimizes the molar ratio between the methylhydrazine aqueous solution, ethyl trifluoroacetoacetate, and the preferred acidic reagent, and controls the cyclization reaction conditions and the acidolysis reaction conditions to ensure that the purity of the obtained 5-hydroxy-1-methyl-3-trifluoromethyl-1H-pyrazole is ≥96wt% and the yield is ≥87%, meeting the requirements of the subsequent preparation process.

[0053] 4. The present invention comprehensively controls the conditions of the salt-forming reaction and the difluoromethylation reaction, uses sodium hydroxide or potassium hydroxide as an alkaline reagent, and uses tetrahydrofuran, acetonitrile or 2-methyltetrahydrofuran as an organic solvent to ensure that the purity of the prepared 5-difluoromethoxy-1-methyl-3-trifluoromethyl-1H-pyrazole is ≥97wt% and the yield is ≥97%.

[0054] 5. The present invention controls the molar ratio of 5-difluoromethoxy-1-methyl-3-trifluoromethyl-1H-pyrazole, sodium methanesulfonate, and the catalyst, and especially adopts one of Cu(OTf)2, Pd(PPh3)4, or Ce(NH4)4(SO4)4 as the catalyst, thereby achieving a low-temperature reaction while maintaining a product purity of ≥95wt% and a yield of ≥93%. BRIEF DESCRIPTION OF THE DRAWINGS

[0055] Figure 1 The sulfonepyraclostrobin intermediate prepared in Example 1 1 H NMR spectrum. DETAILED DESCRIPTION

[0056] Example 1

[0057] Example 1 of the present invention provides a method for preparing a sulfonepyraclostrobin intermediate, comprising the following steps:

[0058] (1) Controlling the temperature, a methylhydrazine aqueous solution (32.2 g, 0.28 mol, 1.05 eq.) was added dropwise to ethyl trifluoroacetoacetate (50 g, 0.27 mol, 1 eq.), and the mixture was kept warm for a cyclization reaction; an acidic reagent (2.63 g, 0.03 mol, 0.1 eq.) was added for an acidolysis reaction, and water (150 g) was added after the reaction was completed. The mixture was cooled (25° C.) and filtered to obtain 5-hydroxy-1-methyl-3-trifluoromethyl-1H-pyrazole (39.96 g);

[0059] (2) 5-Hydroxy-1-methyl-3-trifluoromethyl-1H-pyrazole (39.96 g, 0.23 mol, 1 eq.) and an alkaline reagent (27.57 g, 0.42 mol, 1.8 eq.) were reacted in 160 g of an organic solvent to form a salt; difluorochloromethane (21.07 g, 0.24 mol, 1.05 eq.) was introduced under controlled temperature to carry out a difluoromethylation reaction; after completion of the reaction, water (50 g) was added, and the mixture was washed and separated. The organic layer was desolventized and distilled to obtain 5-difluoromethoxy-1-methyl-3-trifluoromethyl-1H-pyrazole (50.6 g);

[0060] (3) 5-Difluoromethoxy-1-methyl-3-trifluoromethyl-1H-pyrazole (50.6 g, 0.23 mol, 1 eq.) and sodium methanesulfonate (30.5 g, 0.25 mol, 1.1 eq.) were dissolved in 150 g of solvent, and a coupling reaction was carried out under the action of light (blue LED light source, wavelength of 460-465 nm) and a catalyst (1.68 g, 4.55 mmol, 0.02 eq.). After the reaction, the temperature was cooled to 25° C., and a 5 wt% aqueous hydrochloric acid solution was added to adjust the pH to 2.5. The mixture was filtered and separated, and the aqueous layer was desolvated under negative pressure to obtain a sulfonepyrazoline intermediate (68.84 g).

[0061] The temperature of the cyclization reaction is 5° C. and the time is 30 min.

[0062] The temperature of the acid hydrolysis reaction is 55° C. and the time is 2 h.

[0063] The mass proportion of methylhydrazine in the methylhydrazine aqueous solution is 40%.

[0064] The acidic reagent is concentrated hydrochloric acid (37 wt % hydrochloric acid aqueous solution, the same below).

[0065] The purity of the 5-hydroxy-1-methyl-3-trifluoromethyl-1H-pyrazole is 96.47 wt %, and the yield is 87.20%.

[0066] The alkaline reagent is potassium hydroxide.

[0067] The organic solvent is tetrahydrofuran.

[0068] The temperature of the salt-forming reaction is 40° C. and the time is 1 h.

[0069] The difluoromethylation reaction temperature is 65° C. and the reaction time is 1 h.

[0070] The purity of the 5-difluoromethoxy-1-methyl-3-trifluoromethyl-1H-pyrazole was 97.23 wt %, and the yield was 98.10%.

[0071] The coupling reaction temperature is 40° C. and the reaction time is 6 h.

[0072] The solvent is tetrahydrofuran.

[0073] The catalyst is Cu(OTf)2.

[0074] The purity of the sulfonepyrazoline intermediate (5-difluoromethoxy-1-methyl-3-trifluoromethyl-1H-pyrazole-4-methanesulfonic acid) is 96.54 wt %, and the yield is 94.10%.

[0075] Example 2

[0076] Example 2 of the present invention provides a method for preparing a sulfonepyraclostrobin intermediate, comprising the following steps:

[0077] (1) Controlling the temperature, a methylhydrazine aqueous solution (32.2 g, 0.28 mol, 1.05 eq.) was added dropwise to ethyl trifluoroacetoacetate (50 g, 0.27 mol, 1 eq.), and the mixture was kept warm for a cyclization reaction; an acidic reagent (2.63 g, 0.03 mol, 0.1 eq.) was added for an acidolysis reaction, and water (150 g) was added after the reaction was completed. The mixture was cooled (25° C.) and filtered to obtain 5-hydroxy-1-methyl-3-trifluoromethyl-1H-pyrazole (40.48 g);

[0078] (2) 5-Hydroxy-1-methyl-3-trifluoromethyl-1H-pyrazole (40.48 g, 0.24 mol, 1 eq.) and an alkaline reagent (27.95 g, 0.42 mol, 1.8 eq.) were reacted in 160 g of an organic solvent to form a salt; difluorochloromethane (22.38 g, 0.26 mol, 1.1 eq.) was introduced under controlled temperature to carry out a difluoromethylation reaction; after the reaction was completed, water (50 g) was added, and the mixture was washed and separated. The organic layer was desolventized and distilled to obtain 5-difluoromethoxy-1-methyl-3-trifluoromethyl-1H-pyrazole (51.08 g);

[0079] (3) 5-Difluoromethoxy-1-methyl-3-trifluoromethyl-1H-pyrazole (51.08 g, 0.23 mol, 1 eq.) and sodium methanesulfonate (30.97 g, 0.25 mol, 1.1 eq.) were dissolved in 150 g of solvent, and a coupling reaction was carried out under the action of light (blue LED light source, wavelength of 460-465 nm) and a catalyst (5.4 g, 4.63 mmol, 0.02 eq.). After the reaction, the temperature was cooled to 25° C., and a 5 wt% aqueous hydrochloric acid solution was added to adjust the pH to 2.5. The mixture was filtered and separated, and the aqueous layer was desolvated under negative pressure to obtain a sulfonepyrazoline intermediate (69.57 g).

[0080] The temperature of the cyclization reaction is 12° C. and the time is 30 min.

[0081] The temperature of the acid hydrolysis reaction is 60° C. and the time is 2 h.

[0082] The mass proportion of methylhydrazine in the methylhydrazine aqueous solution is 40%.

[0083] The acidic reagent is concentrated hydrochloric acid.

[0084] The purity of the 5-hydroxy-1-methyl-3-trifluoromethyl-1H-pyrazole is 96.53 wt %, and the yield is 88.40%.

[0085] The alkaline reagent is potassium hydroxide.

[0086] The organic solvent is tetrahydrofuran.

[0087] The temperature of the salt-forming reaction is 45° C. and the time is 1 h.

[0088] The difluoromethylation reaction temperature is 55° C. and the reaction time is 1 h.

[0089] The purity of the 5-difluoromethoxy-1-methyl-3-trifluoromethyl-1H-pyrazole is 97.85 wt %, and the yield is 98.3%.

[0090] The coupling reaction temperature is 45° C. and the reaction time is 5 h.

[0091] The solvent is tetrahydrofuran.

[0092] The catalyst is Pd(PPh3)4.

[0093] The purity of the sulfonepyrazoline intermediate (5-difluoromethoxy-1-methyl-3-trifluoromethyl-1H-pyrazole-4-methanesulfonic acid) is 96.11 wt %, and the yield is 93.2%.

[0094] Example 3

[0095] Example 3 of the present invention provides a method for preparing a sulfonepyraclostrobin intermediate, comprising the following steps:

[0096] (1) Controlling the temperature, a methylhydrazine aqueous solution (30.65 g, 0.27 mol, 1 eq.) was added dropwise to ethyl trifluoroacetoacetate (50 g, 0.27 mol, 1 eq.), and the mixture was kept warm for a cyclization reaction; an acidic reagent (5.25 g, 0.05 mol, 0.2 eq.) was added for an acidolysis reaction, and water (150 g) was added after the reaction was completed. The mixture was cooled (25° C.) and filtered to obtain 5-hydroxy-1-methyl-3-trifluoromethyl-1H-pyrazole (40.57 g);

[0097] (2) 5-Hydroxy-1-methyl-3-trifluoromethyl-1H-pyrazole (40.57 g, 0.24 mol, 1 eq.) and an alkaline reagent (31.34 g, 0.47 mol, 2.0 eq.) were reacted in 160 g of an organic solvent to form a salt; difluorochloromethane (24.63 g, 0.28 mol, 1.20 eq.) was introduced under controlled temperature to carry out a difluoromethylation reaction; after completion of the reaction, water (50 g) was added, and the mixture was washed and separated. The organic layer was desolventized and distilled to obtain 5-difluoromethoxy-1-methyl-3-trifluoromethyl-1H-pyrazole (50.9 g);

[0098] (3) 5-Difluoromethoxy-1-methyl-3-trifluoromethyl-1H-pyrazole (50.9 g, 0.23 mol, 1 eq.) and sodium methanesulfonate (29.58 g, 0.24 mol, 1.05 eq.) were dissolved in 150 g of solvent, and a coupling reaction was carried out under the action of light (blue LED light source, wavelength of 460-465 nm) and a catalyst (6.83 g, 18.51 mmol, 0.08 eq.). After the reaction, the temperature was cooled to 25° C., and a 5 wt% aqueous hydrochloric acid solution was added to adjust the pH to 2.5. The mixture was filtered and separated, and the aqueous layer was desolvated under negative pressure to obtain a sulfonepyrazoline intermediate (70.02 g).

[0099] The temperature of the cyclization reaction is 15° C. and the time is 30 min.

[0100] The temperature of the acid hydrolysis reaction is 60° C. and the time is 2 h.

[0101] The mass proportion of methylhydrazine in the methylhydrazine aqueous solution is 40%.

[0102] The acidic reagent is concentrated hydrochloric acid.

[0103] The purity of the 5-hydroxy-1-methyl-3-trifluoromethyl-1H-pyrazole is 97.20 wt %, and the yield is 89.20%.

[0104] The alkaline reagent is potassium hydroxide.

[0105] The organic solvent is acetonitrile.

[0106] The temperature of the salt-forming reaction is 45° C. and the time is 1 h.

[0107] The difluoromethylation reaction temperature is 70° C. and the reaction time is 1 h.

[0108] The purity of the 5-difluoromethoxy-1-methyl-3-trifluoromethyl-1H-pyrazole is 98.23 wt %, and the yield is 97.46%.

[0109] The coupling reaction temperature was 45° C. and the reaction time was 5.5 h.

[0110] The solvent is dichloroethane.

[0111] The catalyst is Cu(OTf)2.

[0112] The purity of the sulfonepyraclostrobin intermediate (5-difluoromethoxy-1-methyl-3-trifluoromethyl-1H-pyrazole-4-methanesulfonic acid) is 95.84 wt %, and the yield is 93.50%.

[0113] Example 4

[0114] Example 4 of the present invention provides a method for preparing a sulfonepyraclostrobin intermediate, comprising the following steps:

[0115] (1) Controlling the temperature, a methylhydrazine aqueous solution (30.65 g, 0.27 mol, 1 eq.) was added dropwise to ethyl trifluoroacetoacetate (50 g, 0.27 mol, 1 eq.), and the mixture was kept warm for a cyclization reaction; an acidic reagent (3.2 g, 0.05 mol, 0.2 eq.) was added for an acidolysis reaction, and water (150 g) was added after the reaction was completed. The mixture was cooled (25° C.) and filtered to obtain 5-hydroxy-1-methyl-3-trifluoromethyl-1H-pyrazole (40.31 g);

[0116] (2) 5-Hydroxy-1-methyl-3-trifluoromethyl-1H-pyrazole (40.31 g, 0.23 mol, 1 eq.) and an alkaline reagent (19.08 g, 0.47 mol, 2.0 eq.) were reacted in 160 g of an organic solvent to form a salt; difluorochloromethane (21.07 g, 0.24 mol, 1.05 eq.) was introduced under controlled temperature to carry out a difluoromethylation reaction; after completion of the reaction, water (50 g) was added, and the layers were washed and separated. The organic layer was desolventized and distilled to obtain 5-difluoromethoxy-1-methyl-3-trifluoromethyl-1H-pyrazole (50.63 g);

[0117] (3) 5-Difluoromethoxy-1-methyl-3-trifluoromethyl-1H-pyrazole (50.63 g, 0.23 mol, 1 eq.) and sodium methanesulfonate (29.39 g, 0.24 mol, 1.05 eq.) were dissolved in 150 g of solvent, and a coupling reaction was carried out under the action of light (blue LED light source, wavelength of 460-465 nm) and a catalyst (7.27 g, 11.5 mmol, 0.05 eq.). After the reaction, the temperature was cooled to 25° C., and a 5 wt% aqueous hydrochloric acid solution was added to adjust the pH to 2.5. The mixture was filtered and separated, and the aqueous layer was desolvated under negative pressure to obtain a sulfonepyrazoline intermediate (69.42 g).

[0118] The temperature of the cyclization reaction is 20° C. and the time is 30 min.

[0119] The temperature of the acid hydrolysis reaction is 70° C. and the time is 2 h.

[0120] The mass proportion of methylhydrazine in the methylhydrazine aqueous solution is 40%.

[0121] The acidic reagent is concentrated hydrochloric acid.

[0122] The purity of the 5-hydroxy-1-methyl-3-trifluoromethyl-1H-pyrazole is 96.28 wt %, and the yield is 87.80%.

[0123] The alkaline reagent is sodium hydroxide.

[0124] The organic solvent is acetonitrile.

[0125] The temperature of the salt-forming reaction is 60° C. and the time is 1 h.

[0126] The difluoromethylation reaction temperature is 60° C. and the reaction time is 1 h.

[0127] The purity of the 5-difluoromethoxy-1-methyl-3-trifluoromethyl-1H-pyrazole is 98.15 wt %, and the yield is 98.4%.

[0128] The coupling reaction temperature is 60° C. and the reaction time is 6 h.

[0129] The solvent is dichloroethane.

[0130] The catalyst is Ce(NH4)4(SO4)4 dihydrate.

[0131] The purity of the sulfonepyrazoline intermediate (5-difluoromethoxy-1-methyl-3-trifluoromethyl-1H-pyrazole-4-methanesulfonic acid) is 96.37 wt %, and the yield is 93.80%.

[0132] Example 5

[0133] Example 5 of the present invention provides a method for preparing a sulfonepyraclostrobin intermediate, comprising the following steps:

[0134] (1) Controlling the temperature, a methylhydrazine aqueous solution (36.78 g, 0.32 mol, 1.20 eq.) was added dropwise to ethyl trifluoroacetoacetate (50 g, 0.27 mol, 1 eq.), and the mixture was kept warm for a cyclization reaction; an acidic reagent (1.6 g, 0.03 mol, 0.1 eq.) was added for an acidolysis reaction, and water (150 g) was added after the reaction was completed. The mixture was cooled (25° C.) and filtered to obtain 5-hydroxy-1-methyl-3-trifluoromethyl-1H-pyrazole (41.41 g);

[0135] (2) 5-Hydroxy-1-methyl-3-trifluoromethyl-1H-pyrazole (41.41 g, 0.24 mol, 1 eq.) and an alkaline reagent (21.8 g, 0.53 mol, 2.2 eq.) were reacted in 165 g of an organic solvent to form a salt; difluorochloromethane (23.09 g, 0.27 mol, 1.1 eq.) was introduced under controlled temperature to carry out a difluoromethylation reaction; after completion of the reaction, water (50 g) was added, and the mixture was washed and separated. The organic layer was desolventized and distilled to obtain 5-difluoromethoxy-1-methyl-3-trifluoromethyl-1H-pyrazole (52.62 g);

[0136] (3) 5-Difluoromethoxy-1-methyl-3-trifluoromethyl-1H-pyrazole (52.62 g, 0.24 mol, 1 eq.) and sodium methanesulfonate (34.68 g, 0.28 mol, 1.2 eq.) were dissolved in 158 g of solvent, and a coupling reaction was carried out under the action of light (blue LED light source, wavelength of 460-465 nm) and a catalyst (7.51 g, 11.87 mmol, 0.05 eq.). After the reaction, the temperature was cooled to 25° C., and a 5 wt% aqueous hydrochloric acid solution was added to adjust the pH to 2.5. The mixture was filtered and separated, and the aqueous layer was desolvated under negative pressure to obtain a sulfonepyrazoline intermediate (73.16 g).

[0137] The temperature of the cyclization reaction is 15° C. and the time is 30 min.

[0138] The temperature of the acid hydrolysis reaction is 50° C. and the time is 2 h.

[0139] The mass proportion of methylhydrazine in the methylhydrazine aqueous solution is 40%.

[0140] The acidic reagent is acetic acid.

[0141] The purity of the 5-hydroxy-1-methyl-3-trifluoromethyl-1H-pyrazole is 97.35 wt %, and the yield is 91.20%.

[0142] The alkaline reagent is sodium hydroxide.

[0143] The organic solvent is 2-methyltetrahydrofuran.

[0144] The temperature of the salt-forming reaction is 55° C. and the time is 1 h.

[0145] The difluoromethylation reaction temperature is 70° C. and the reaction time is 1 h.

[0146] The purity of the 5-difluoromethoxy-1-methyl-3-trifluoromethyl-1H-pyrazole is 97.49 wt %, and the yield is 97.80%.

[0147] The coupling reaction temperature is 60° C. and the reaction time is 5 h.

[0148] The solvent is 2-methyltetrahydrofuran.

[0149] The catalyst is Ce(NH4)4(SO4)4 dihydrate.

[0150] The purity of the sulfonepyrazoline intermediate (5-difluoromethoxy-1-methyl-3-trifluoromethyl-1H-pyrazole-4-methanesulfonic acid) is 95.82 wt %, and the yield is 95.20%.

[0151] Example 6

[0152] Example 6 of the present invention provides a method for preparing a sulfonepyraclostrobin intermediate, comprising the following steps:

[0153] (1) Controlling the temperature, a methylhydrazine aqueous solution (36.78 g, 0.32 mol, 1.20 eq.) was added dropwise to ethyl trifluoroacetoacetate (50 g, 0.27 mol, 1 eq.), and the mixture was kept warm for a cyclization reaction; an acidic reagent (1.6 g, 0.03 mol, 0.1 eq.) was added for an acidolysis reaction, and water (150 g) was added after the reaction was completed. The mixture was cooled (25° C.) and filtered to obtain 5-hydroxy-1-methyl-3-trifluoromethyl-1H-pyrazole (41.49 g);

[0154] (2) 5-Hydroxy-1-methyl-3-trifluoromethyl-1H-pyrazole (41.49 g, 0.24 mol, 1 eq.) and an alkaline reagent (24.58 g, 0.60 mol, 2.5 eq.) were reacted in 165 g of an organic solvent to form a salt; difluorochloromethane (25 g, 0.29 mol, 1.2 eq.) was introduced under controlled temperature to carry out a difluoromethylation reaction; after completion of the reaction, water (50 g) was added, and the mixture was washed and separated. The organic layer was desolventized and distilled to obtain 5-difluoromethoxy-1-methyl-3-trifluoromethyl-1H-pyrazole (52.06 g);

[0155] (3) 5-Difluoromethoxy-1-methyl-3-trifluoromethyl-1H-pyrazole (52.06 g, 0.24 mol, 1 eq.) and sodium methanesulfonate (34.73 g, 0.29 mol, 1.2 eq.) were dissolved in 156 g of solvent, and a coupling reaction was carried out under the action of light (blue LED light source, wavelength of 460-465 nm) and a catalyst (8.77 g, 23.77 mmol, 0.1 eq.). After the reaction, the temperature was cooled to 25° C., and a 5 wt% aqueous hydrochloric acid solution was added to adjust the pH to 2.5. The mixture was filtered and the layers were separated, and the aqueous layer was desolvated under negative pressure to obtain a sulfonepyrazoline intermediate (71.23 g).

[0156] The temperature of the cyclization reaction is 8° C. and the time is 30 min.

[0157] The temperature of the acid hydrolysis reaction is 50° C. and the time is 2 h.

[0158] The mass proportion of methylhydrazine in the methylhydrazine aqueous solution is 40%.

[0159] The acidic reagent is acetic acid.

[0160] The purity of the 5-hydroxy-1-methyl-3-trifluoromethyl-1H-pyrazole is 96.42 wt %, and the yield is 90.50%.

[0161] The alkaline reagent is sodium hydroxide.

[0162] The organic solvent is 2-methyltetrahydrofuran.

[0163] The temperature of the salt-forming reaction is 55° C. and the time is 1 h.

[0164] The difluoromethylation reaction temperature is 55° C. and the reaction time is 1 h.

[0165] The purity of the 5-difluoromethoxy-1-methyl-3-trifluoromethyl-1H-pyrazole is 98.68 wt %, and the yield is 98.70%.

[0166] The coupling reaction temperature is 420° C. and the reaction time is 5.5 h.

[0167] The solvent is 2-methyltetrahydrofuran.

[0168] The catalyst is Cu(OTf)2.

[0169] The purity of the sulfonepyrazoline intermediate (5-difluoromethoxy-1-methyl-3-trifluoromethyl-1H-pyrazole-4-methanesulfonic acid) is 96.39 wt %, and the yield is 93.10%.

[0170] Comparative Example 1

[0171] Comparative Example 1 of the present invention provides a method for preparing a sulfonepyraclostrobin intermediate, comprising the following steps:

[0172] (1) Controlling the temperature, a methylhydrazine aqueous solution (33.72 g, 0.29 mol, 1.1 eq.) was added dropwise to ethyl trifluoroacetoacetate (50 g, 0.27 mol, 1 eq.), and the mixture was kept warm for a cyclization reaction; an acidic reagent (8.69 g, 0.03 mol, 0.1 eq.) was added for an acidolysis reaction, and water (150 g) was added after the reaction was completed. The mixture was cooled (25° C.) and filtered to obtain 5-hydroxy-1-methyl-3-trifluoromethyl-1H-pyrazole (35.84 g);

[0173] (2) 5-Hydroxy-1-methyl-3-trifluoromethyl-1H-pyrazole (35.84 g, 0.20 mol, 1 eq.) and an alkaline reagent (14.12 g, 0.26 mol, 1.3 eq.) were reacted in 143 g of an organic solvent to form a salt; difluorochloromethane (34.8 g, 0.40 mol, 2 eq.) was introduced under controlled temperature to carry out a difluoromethylation reaction; after the reaction was completed, water (50 g) was added, and the layers were washed and separated. The organic layer was desolventized and distilled to obtain 5-difluoromethoxy-1-methyl-3-trifluoromethyl-1H-pyrazole (38.7 g);

[0174] (3) 5-Difluoromethoxy-1-methyl-3-trifluoromethyl-1H-pyrazole (38.7 g, 0.16 mol, 1 eq.) and sodium methanesulfonate (21.88 g, 0.18 mol, 1.1 eq.) were dissolved in 116 g of solvent, and a coupling reaction was carried out under the action of light (blue LED light source, wavelength of 460-465 nm) and a catalyst (3.3 g, 32.68 mmol, 0.2 eq.). After the reaction, the temperature was cooled to 25° C., and a 5 wt% aqueous hydrochloric acid solution was added to adjust the pH to 2.5. The mixture was filtered and the layers were separated, and the aqueous layer was desolvated under negative pressure to obtain a sulfonepyraclostrobin intermediate (43.21 g).

[0175] The temperature of the cyclization reaction is 35° C. and the time is 30 min.

[0176] The temperature of the acid hydrolysis reaction is 50° C. and the time is 2 h.

[0177] The mass proportion of methylhydrazine in the methylhydrazine aqueous solution is 40%.

[0178] The acidic reagent is a 30 wt% sulfuric acid aqueous solution.

[0179] The purity of the 5-hydroxy-1-methyl-3-trifluoromethyl-1H-pyrazole is 93.24 wt %, and the yield is 75.60%.

[0180] The alkaline reagent is sodium methoxide.

[0181] The organic solvent is toluene.

[0182] The temperature of the salt-forming reaction is 20° C. and the time is 1 h.

[0183] The difluoromethylation reaction temperature is 85° C. and the reaction time is 1 h.

[0184] The purity of the 5-difluoromethoxy-1-methyl-3-trifluoromethyl-1H-pyrazole is 91.23 wt %, and the yield is 81.20%.

[0185] The coupling reaction temperature is 40° C. and the reaction time is 6 h.

[0186] The solvent is dichloromethane.

[0187] The catalyst is CuCl.

[0188] The purity of the sulfonepyrazoline intermediate (5-difluoromethoxy-1-methyl-3-trifluoromethyl-1H-pyrazole-4-methanesulfonic acid) is 84.56 wt %, and the yield is 72.10%.

[0189] Comparative Example 2

[0190] Comparative Example 2 of the present invention provides a method for preparing a sulfonepyraclostrobin intermediate, comprising the following steps:

[0191] (1) Controlling the temperature, a methylhydrazine aqueous solution (39.85 g, 0.35 mol, 1.3 eq.) was added dropwise to ethyl trifluoroacetoacetate (50 g, 0.27 mol, 1 eq.), and the mixture was kept warm for a cyclization reaction; an acidic reagent (8.69 g, 0.03 mol, 0.1 eq.) was added for an acidolysis reaction, and water (150 g) was added after the reaction was completed. The mixture was cooled (25° C.) and filtered to obtain 5-hydroxy-1-methyl-3-trifluoromethyl-1H-pyrazole (32.86 g);

[0192] (2) 5-Hydroxy-1-methyl-3-trifluoromethyl-1H-pyrazole (32.86 g, 0.18 mol, 1 eq.) and an alkaline reagent (19.36 g, 0.27 mol, 1.5 eq.) were reacted in 131 g of an organic solvent to form a salt; difluorochloromethane (23.65 g, 0.27 mol, 1.5 eq.) was introduced under controlled temperature to carry out a difluoromethylation reaction; after the reaction, water (50 g) was added, and the mixture was washed and separated. The organic layer was desolventized and distilled to obtain 5-difluoromethoxy-1-methyl-3-trifluoromethyl-1H-pyrazole (32.9 g);

[0193] (3) 5-Difluoromethoxy-1-methyl-3-trifluoromethyl-1H-pyrazole (32.90 g, 0.14 mol, 1 eq.) and sodium methanesulfonate (41.81 g, 0.34 mol, 2.5 eq.) were dissolved in 100 g of solvent, and a coupling reaction was carried out under the action of light (blue LED light source, wavelength of 460-465 nm) and a catalyst (5.33 g, 41.22 mmol, 0.3 eq.). After the reaction, the temperature was lowered to 25° C., and a 5 wt% aqueous hydrochloric acid solution was added to adjust the pH to 2.5. The mixture was filtered and separated, and the aqueous layer was desolvated under negative pressure to obtain a sulfonepyrazoline intermediate (29.54 g).

[0194] The temperature of the cyclization reaction is 8° C. and the time is 30 min.

[0195] The temperature of the acid hydrolysis reaction is 60° C. and the time is 2 h.

[0196] The mass proportion of methylhydrazine in the methylhydrazine aqueous solution is 40%.

[0197] The acidic reagent is a 30 wt% sulfuric acid aqueous solution.

[0198] The purity of the 5-hydroxy-1-methyl-3-trifluoromethyl-1H-pyrazole is 92.16 wt %, and the yield is 68.50%.

[0199] The alkaline reagent is potassium methoxide.

[0200] The organic solvent is N,N-dimethylformamide.

[0201] The temperature of the salt-forming reaction is 55° C. and the time is 1 h.

[0202] The difluoromethylation reaction temperature is 110° C. and the reaction time is 1 h.

[0203] The purity of the 5-difluoromethoxy-1-methyl-3-trifluoromethyl-1H-pyrazole is 90.25 wt %, and the yield is 75.36%.

[0204] The coupling reaction temperature is 40° C. and the reaction time is 6 h.

[0205] The solvent is dichloroethane.

[0206] The catalyst is FeCl2.

[0207] The purity of the sulfonepyrazoline intermediate (5-difluoromethoxy-1-methyl-3-trifluoromethyl-1H-pyrazole-4-methanesulfonic acid) is 80.22 wt %, and the yield is 55.60%.

[0208] Comparative Example 3

[0209] Comparative Example 3 of the present invention provides a method for preparing a sulfonepyraclostrobin intermediate, comprising the following steps:

[0210] (1) Controlling the temperature, a methylhydrazine aqueous solution (36.78 g, 0.32 mol, 1.2 eq.) was added dropwise to ethyl trifluoroacetoacetate (50 g, 0.27 mol, 1 eq.), and the mixture was kept warm for a cyclization reaction; an acidic reagent (7.99 g, 0.13 mol, 0.5 eq.) was added for an acidolysis reaction, and water (150 g) was added after the reaction was completed. The mixture was cooled (25° C.) and filtered to obtain 5-hydroxy-1-methyl-3-trifluoromethyl-1H-pyrazole (34.29 g);

[0211] (2) 5-Hydroxy-1-methyl-3-trifluoromethyl-1H-pyrazole (34.29 g, 0.19 mol, 1 eq.) and an alkaline reagent (16.54 g, 0.22 mol, 12 eq.) were reacted in 140 g of an organic solvent to form a salt; difluorochloromethane (17.77 g, 0.21 mol, 1.1 eq.) was introduced under controlled temperature to carry out a difluoromethylation reaction; after completion of the reaction, water (50 g) was added, and the mixture was washed and separated. The organic layer was desolventized and distilled to obtain 5-difluoromethoxy-1-methyl-3-trifluoromethyl-1H-pyrazole (28.64 g);

[0212] (3) 5-Difluoromethoxy-1-methyl-3-trifluoromethyl-1H-pyrazole (28.64 g, 0.12 mol, 1 eq.) and sodium methanesulfonate (17.88 g, 0.15 mol, 1.2 eq.) were dissolved in 85 g of solvent, and a coupling reaction was carried out under the action of light (blue LED light source, wavelength of 460-465 nm) and a catalyst (3.09 g, 24.48 mmol, 0.2 eq.). After the reaction, the temperature was cooled to 25° C., and a 5 wt% aqueous hydrochloric acid solution was added to adjust the pH to 2.5. The mixture was filtered and separated, and the aqueous layer was desolvated under negative pressure to obtain a sulfonepyrazoline intermediate (29.28 g).

[0213] The temperature of the cyclization reaction is 20° C. and the time is 30 min.

[0214] The temperature of the acid hydrolysis reaction is 75° C. and the time is 2 h.

[0215] The mass proportion of methylhydrazine in the methylhydrazine aqueous solution is 40%.

[0216] The acidic reagent is acetic acid.

[0217] The purity of the 5-hydroxy-1-methyl-3-trifluoromethyl-1H-pyrazole is 90.51 wt %, and the yield is 70.20%.

[0218] The alkaline reagent is potassium methoxide.

[0219] The organic solvent is 2-methyltetrahydrofuran.

[0220] The temperature of the salt-forming reaction is 10° C. and the time is 1 h.

[0221] The difluoromethylation reaction temperature is 25° C. and the reaction time is 1 h.

[0222] The purity of the 5-difluoromethoxy-1-methyl-3-trifluoromethyl-1H-pyrazole is 92.35 wt %, and the yield is 65.50%.

[0223] The coupling reaction temperature is 60° C. and the reaction time is 6 h.

[0224] The solvent is 2-methyltetrahydrofuran.

[0225] The catalyst is Cu(OAc)2.

[0226] The purity of the sulfonepyrazoline intermediate (5-difluoromethoxy-1-methyl-3-trifluoromethyl-1H-pyrazole-4-methanesulfonic acid) is 87.12 wt %, and the yield is 67.20%.

Claims

1. A method for preparing a sulfonepyraclostrobin intermediate, characterized in that: The following steps are involved: The temperature is controlled, and a methylhydrazine aqueous solution is added dropwise to ethyl trifluoroacetoacetate, and the temperature is kept warm for a cyclization reaction; an acidic reagent is added for an acidolysis reaction to obtain 5-hydroxy-1-methyl-3-trifluoromethyl-1H-pyrazole; 5-hydroxy-1-methyl-3-trifluoromethyl-1H-pyrazole and an alkaline reagent are reacted in an organic solvent to form a salt; difluorochloromethane is introduced under controlled temperature for a difluoromethylation reaction to obtain 5-difluoromethoxy-1-methyl-3-trifluoromethyl-1H-pyrazole (Compound II); 5-difluoromethoxy-1-methyl-3-trifluoromethyl-1H-pyrazole and sodium methanesulfonate are dissolved in a solvent, and a coupling reaction is carried out under light and a catalyst to obtain a sulfonepyrazoline intermediate.

2. The method for preparing a sulfonepyraclostrobin intermediate according to claim 1, wherein: The temperature of the cyclization reaction is 0-25° C., and the time is 20-40 minutes; the temperature of the acidolysis reaction is 40-75° C., and the time is 1.5-2.5 hours.

3. The method for preparing a sulfonepyraclostrobin intermediate according to claim 1, wherein: The acidic reagent is at least one of hydrochloric acid, sulfuric acid, nitric acid, acetic acid or formic acid.

4. The method for preparing a sulfonepyraclostrobin intermediate according to claim 1, wherein: The alkaline reagent is at least one of sodium hydroxide, sodium ethoxide, sodium methoxide, potassium hydroxide, potassium tert-butoxide or potassium methoxide.

5. The method for preparing a sulfonepyraclostrobin intermediate according to claim 1, wherein: The organic solvent is at least one of tetrahydrofuran, N,N-dimethylformamide, N,N-dimethylacetamide, 2-methyltetrahydrofuran, 1,4-dioxane, acetonitrile or toluene.

6. The method for preparing a sulfonepyraclostrobin intermediate according to claim 1, wherein: The temperature of the salt-forming reaction is 30-80° C., and the time is 0.8-1.5 h; the temperature of the difluoromethylation reaction is 40-90° C., and the time is 0.8-1.5 h.

7. The method for preparing a sulfonepyraclostrobin intermediate according to claim 1, wherein: The molar ratio of the 5-hydroxy-1-methyl-3-trifluoromethyl-1H-pyrazole, the alkaline reagent and difluorochloromethane is 1: (1-3.5): (0.9-2.5).

8. The method for preparing a sulfonepyraclostrobin intermediate according to claim 1, wherein: The coupling reaction temperature is 20-80° C. and the reaction time is 4-7 hours.

9. The method for preparing a sulfonepyraclostrobin intermediate according to claim 1, wherein: The molar ratio of the 5-difluoromethoxy-1-methyl-3-trifluoromethyl-1H-pyrazole, sodium methanesulfonate and the catalyst is 1: (0.85-2): (0.015-0.3).

10. The method for preparing a sulfonepyraclostrobin intermediate according to claim 1, wherein: The catalyst is at least one of CuBr2, Cu(OAc)2, CuCl, Cu(OTf)2, FeCl2, Nd(OTf)3, CsOAc, Pd(PPh3)4, Ru(bpy)3Cl2 or Ce(NH4)4(SO4)4.

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