Phenylhydrazine hydrochloride → 3-(perfluoroethyl)-1-phenyl-1H-pyrazol-5-amine

Participants

Reaction Conditions

Reaction Steps

A stirred mixture of 4,4,5,5,5-pentafluoro-3-oxopentanenitrile (500 mg, 2.66 mmol) and phenylhydrazine hydrochloride (386 mg, 2.66 mmol) in ethanol (5 mL) was heated at 90° C. for 4 h. The reaction mixture was concentrated under reduced pressure, and the obtained oil purified by silica gel flash column chromatography (eluting with a gradient of 100% petroleum ether to 10% ethyl acetate in petroleum ether) to afford 3-(perfluoroethyl)-1-phenyl-1H-pyrazol-5-amine (320 mg, 43%) as a solid. 1H NMR (400 MHz, CDCl3) δ 7.51-7.60 (m, 4H), 7.45 (m, 1H), 5.91 (s, 1H), 3.96 (brs, 2H); LC-MS (ESI) m/z 278 (M+H)+.

Provenance & Evidence