Methane → 4,5-Dihydro-1-(3-(trifluoromethyl)phenyl)-1H-pyrazol-3-amine

Participants

Reaction Conditions

Reaction Steps

Under ice-cooling, 10 drops of a 50% choline solution was added to a mixture of 20.0 g of 3-(trifluoromethyl)phenylhydrazine and 6.63 g of acrylonitrile, and the mixture was heated at 95° C. for one hour. After allowed to stand for cooling, 22 ml of 1N hydrochloric acid was added and the mixture was stirred at 95° C. for 10 minutes. After subjecting the mixture to hot activated charcoal treatment, the mixture was adjusted to an alkaline pH with a 10% aqueous sodium hydroxide solution under ice-cooling. Precipitated crystals were collected by filtration and washed, and recrystallized from a mixed solution of hexane and ethyl acetate to give 17.27 g of 1-[3-(trifluoromethyl)phenyl]-3-amino-2-pyrazoline (yield: 66%, melting point: 104°-107° C.).

Provenance & Evidence