Thionyl Chloride → 3-(4-t-Butylphenyl)-4-chlorocarbonyl-1-(4-cyanophenyl)-2-methyl-2H-pyrazol-5-one

Participants

Reaction Steps

A mixture of 12.1 g of 3-(4-t-butylphenyl)-1-(4-cyanophenyl)-4-hydroxycarbonyl-2-methyl-2H-pyrazol-5-one and 100 ml of thionyl chloride was stirred at room temperature for 1 hour. The reaction solution was concentrated under reduced pressure, and the residue was recrystallized in a liquid mixture of n-hexane-toluene to give 14.0 g of the title compound as pale yellow crystals.

Provenance & Evidence