Trifluoroacetic acid → 2-(5-Cyclohexyl-3-trifluoromethyl-pyrazol-1-yl)-5-methanesulfonyl-pyridine

Participants

Reaction Steps

2-Hydrazino-5-(methylsulfonyl)pyridine hydrochloride (425.2 mg, 1.9 mmol) and TFA (0.44 mL, 5.7 mmol) were mixed in trifluoroethanol (15 mL) and heated at reflux temperature for 15 minutes 4,4,4-trifluoro-1-cyclohexyl-1,3-butanedione (422 mg, 1.9 mmol) in trifluoroethanol (5 ml) was added. The resulting reaction mixture was heated at reflux temperature for 3 hours. The solvent was then removed in vacuo, and the residue was partitioned between EtOAc and water. The organic layer was washed with brine and concentrated in vacuo. The product was purified by flash chromatography using 7:2:0.5 of hexane:diethylamine:methanol to give the title compound (305 mg, 43%).

Provenance & Evidence