Hydrochloric Acid → 5-Amino-1-(4-fluorophenyl)-4-[3-(2-methanesulfonyloxyethyl)benzoyl]pyrazole

Participants

Reaction Steps

To a solution of 5-amino-1-(4-fluorophenyl)-4-[3-(2-hydroxyethyl)benzoyl]pyrazole (0.8 g, 2.5 mmol) in pyridine (10 ml) was added methanesulfonyl chloride (0.29 ml, 3.7 mmol). After 2 h, the reaction mixture was poured into 2 N hydrochloric acid (40 ml) and the product was extracted into ethyl acetate. The organic layer was washed with brine, dried over sodium sulfate, filtered and concentrated in vacuo. The residue was purified by flash chromatography (elution gradient: 40-100% ethyl acetate/hexane) to give 5-amino-1-(4-fluorophenyl)-4-[3-(2-methanesulfonyloxyethyl)benzoyl]pyrazole (0.87 g).

Provenance & Evidence