Thionyl Chloride → 1-methyl-3-(trifluoromethyl)-1H-pyrazole-5-carbonyl chloride

Participants

Reaction Steps

A mixture of 0.19 g of 1-methyl-3-trifluoromethyl-1H-pyrazole-5-carboxylic acid, 0.15 g of thionyl chloride and 5 ml of hexane was heated under reflux for 2 hours. The reaction mixture was concentrated under reduced pressure to obtain 0.14 g of 1-methyl-3-trifluoromethyl-1H-pyrazole-5-carbonyl chloride. To a mixture of 0.22 g of N-(2-aminobenzoyl)-N′-ethoxycarbonylhydrazine and 10 ml of pyridine was added 0.14 g of the resulting 1-methyl-3-trifluoromethyl-1H-pyrazole-5-carbonyl chloride and the mixture was stirred at room temperature for 2 hours. Water was poured into the reaction mixture, and a deposited precipitates were collected by filtration to obtain 0.23 g of the present compound (3) of the formula:

Provenance & Evidence