Hydrochloric Acid → 4-(4-Bromo-2-fluorobenzyl)-3-n-butyl-1-(2-chloro-5-nitrophenyl)-1H-pyrazole-5-carbonyl Chloride

Participants

Reaction Steps

A mixture of 672 mg (1.32 mmol) of 4-(4-bromo-2-fluorobenzyl)-3-n-butyl-1-(2-chloro-5-nitrophenyl)-1H-pyrazole-5-carboxylic acid (from Step C), 2.3 mL of thionyl chloride, and 6 mL of cyclohexane was stirred at reflux under N2 for 4 hours, during which time HCl gas was evolved. The cooled solution was concentrated in vacuo to yield an orange oil, which was used directly in the next step.

Provenance & Evidence