Thionyl Chloride → 5-Amino-1-(6-chloro-1,1,3,3-tetrafluoro-1,3-dihydroisobenzofuran-5-yl)-4-trifluoromethylsulfenylpyrazole

Participants

Reaction Conditions

Reaction Steps

To a suspension wherein 5-amino-1-(6-chloro-1,1,3,3-tetrafluoro-1,3-dihydroisobenzofuran-5-yl)pyrazole (391 mg, 1.27 mmol), sodium trifluromethanesulfinate (397 mg, 2.54 mmol) and dimethylamine tosylate (690 mg, 3.17 mmol) are in toluene (4 ml), thionyl chloride (302 mg, 2.54 mmol) was added dropwise under ice cooling over a period of about 10 minutes and then stirred under heating at 50 to 60° C. for 14 hours. After allowing to cool, the reaction solution was poured into water, extracted with ethyl acetate, and the organic layer was dried over anhydrous magnesium sulfate. The solvent was distilled off under reduced pressure and the residue was subjected to silica gel column chromatography to give 200 mg of 5-amino-1-(6-chloro-1,1,3,3-tetrafluoro-1,3-dihydroisobenzofuran-5-yl)-4-trifluoromethylsulfenylpyrazole.

Provenance & Evidence