反应详情

4-Chloro-3-(4-chloro-2-fluoro-5-methoxyphenyl)-1-methyl-5-trifluoromethyl-1H-pyrazole (1.2 g, 3.5 mmol) was slurried with 4 ml of con. sulfuric acid and was slowly added to a stirred 4 ml mixture of con. sulfuric acid-con. nitric acid (9:1) at −15° C. Solution was allowed to stir at ambient temperature for 2 hr and then added to ice water. Extraction with ethyl acetate and removal of the solvent afforded a crude product which was chromatographed on silica gel. Elution of the column with hexane-methylene chloride (4:6) furnished the title compound (0.72 g).

1. customat −15° C
2. extractionExtraction
3. customwith ethyl acetate and removal of the solvent
4. customafforded a crude product which
5. customwas chromatographed on silica gel
6. washElution of the column with hexane-methylene chloride (4:6)