Thionyl Chloride → 3-(Difluoromethyl)-1-methyl-1 H-pyrazole-4-carbonyl chloride

Participants

Reaction Conditions

Reaction Steps

69.5 g of thionyl chloride (0.58 mol, 1.17 equivalents) are added at 110° C. in the course of 2 hours to a solution of 88 g of 3-difluoromethyl-1-methyl-1H-pyrazole-4-carboxylic acid (0.5 mol) in 440 g of chlorobenzene. The reaction mixture is stirred for 1 hour at 110° C. The reaction mixture is concentrated to a crude product solution. 190 g of 3-difluoromethyl-1-methyl-1H-pyrazole-4-carbonyl chloride (50% in chlorobenzene, yield: 98%) is obtained. The crude product solution is used without being further purified.

Provenance & Evidence