Acetic Acid → 4-(4-fluorophenyl)-3-[4-(methylsulfonyl)phenyl]-1-propargyl-5-(trifluoromethyl)-1H-pyrazole

Participants

Reaction Steps

To a solution of 0.066 mmol of 4-(4-fluorophenyl)-3-[4-(methylthio)phenyl-]1-propargyl-5-(trifluoromethyl)pyrazole from step 2 in 5 mL of glacial acetic acid was added 13 mmol of 30% hydrogen peroxide. The reaction mixture was stirred at room temperature for 72 hours and poured into water. The crude product was purified by HPLC (40% ethyl acetate-hexane) followed by recrystallization from methylene chloride-hexane to give 4-(4-fluorophenyl)-3-[4-(methylsulfonyl)phenyl]-1-propargyl-5-(trifluoromethyl)-1H-pyrazole as white needles (21%): mp 158°-159.5° C.

Provenance & Evidence