Ethyl Acetate → 4,5-Dihydro-1-(4-fluorophenyl)-5-[4-(methylthio)phenyl]pyrazol-3-amine

Participants

Reaction Steps

4-Fluorophenylhydrazine hydrochloride 4 g) was added to a solution of sodium (1.13 g) in ethanol (50 ml), and the mixture was refluxed for 1 hour. To the cooled mixture was added 3-[4-(methylthio)phenyl]acrylonitrile (4.3 g), and the resulting mixture was refluxed overnight. Ethyl acetate and water were added, and the organic layer was separated, dried and concentrated. The oily residue (7.6 g) was purified by column chromatography on silica gel (76 g) eluting with a mixture of toluene and ethyl acetate (2:1) to give brown crystals of 4,5-dihydro-1-(4-fluorophenyl)-5-[4-(methylthio)phenyl]pyrazol-3-amine (5 g).

Provenance & Evidence