Clofibric Acid → 2-(4-Chlorophenoxy)-2-methylpropanoyl chloride

Participants

Reaction Steps

A mixture of 2-(4-chlorophenoxy)-2-methylpropionic acid (15.0 g) and thionyl chloride (70 ml) was boiled under reflux for 1 hour. The thionyl chloride was distilled off and the residue distilled under vacuum to give 2-(4-chlorophenoxy)-2-methylpropionyl chloride, b.p. 84-87° C. at 0.07 mbar. A solution of this chloride (14.17 g) in dichloromethane (50 ml) was added dropwise to a mixture of 1-(3-aminopropyl)imidazole (7.63 g), triethylamine (6.78 g) and dichloromethane (100 ml) at below 0° C. with stirring. After the addition, the mixtures was allowed to warm up to ambient temperature and stirred at this temperature for 2 hours. Saturated aqueous sodium bicarbonate solution (100 ml) was added and the mixture stirred for 1 hour. The mixture was separated and the aqueous layer was washed with dichloromethane. The combined organic layers were dried and evaporated to give a solid which was recrystallised from ethyl acetate to give 2-(4-chlorophenoxy)-N-[3-(imidazol-1-yl)propyl]-2-methylpropionamide, m.p. 83-84° C.

Provenance & Evidence