Water → 2-(4-Fluorophenyl)-4-methyl-5-oxo-3-(pyridin-4-yl)-4,5,6,7-tetrahydropyrazolo[1,5-a]pyrimidine

Participants

Reaction Steps

To a suspension of sodium hydride (60% dispersion in mineral oil, 35 mg) in dry N,N-dimethylformamide (5 ml) was added a solution of 2-(4-fluorophenyl)-5-oxo-3-(pyridin-4-yl)-4,5,6,7-tetrahydropyrazolo[1,5-a]pyrimidine (250 mg) in dry N,N-dimethylformamide (3 ml) dropwise under ice cooling. The mixture was stirred for 30 minutes and to the mixture was added a solution of methyl iodide (125 mg) in dry N,N-dimethylformamide (2 ml). The mixture was stirred at ambient temperature for 2 hours and poured into water. The separated oil was extracted with dichloromethane and the solution was washed with brine, dried and concentrated in vacuo. The residue was purified by column chromatography on silica gel and the obtained crude solid was recrystallized from a mixture of dichloromethane and diisopropyl ether to give 2-(4-fluorophenyl)-4-methyl-5-oxo-3-(pyridin-4-yl)-4,5,6,7 -tetrahydropyrazolo[1,5-a]pyrimidine (180 mg).

Provenance & Evidence