Ethyl Acetate → 4,5,6,7-Tetrahydro-7-[3-(trifluoromethyl)phenyl]pyrazolo[1,5-a]pyrimidine-3-carbonitrile

Participants

Reaction Steps

A mixture of 1.5 parts of 4,5-dihydro-7-[3-(trifluoromethyl)phenyl]pyrazolo[1,5-a]pyrimidine-3-carbonitrile, 50 parts of ethyl acetate, 10 parts of acetic acid and 0.2 parts of 5% palladium-on-carbon catalyst was shaken on a Parr hydrogenator under about 30 pounds of hydrogen pressure for 4.5 hours. The reaction mixture was filtered, and the mother liquor was concentrated to remove the solvent. The yellow oil which was obtained was crystallized by trituration in ether. The crystalline product was recrystallized from ethyl acetate by addition of hexane. The product 4,5,6,7-tetrahydro-7-[3-(trifluoromethyl)phenyl]pyrazolo[1,5-a]pyrimidine-3-carbonitrile melted at 181°-183° C.

Provenance & Evidence