Acetic Acid → 6,7-Difluoro-1-[(1R,2S)-2-fluorocyclopropyl]-5-methyl-4-oxo-1,4-dihydroquinoline-3-carboxylic Acid

Participants

Reaction Steps

A mixture of 1.70 g of ethyl 6,7-difluoro-1-[(1R,2S)-2-fluorocyclopropyl]-5-methyl-4-oxo-1,4-dihydroquinoline-3-carboxylate, 30 ml of concentrated hydrochloric acid, and 60 ml of acetic acid was heated under reflux for 1.5 hours. After allowing to cool, water was added to the reaction mixture. The precipitated crystals were collected by filtration, washed with water and ethanol, and dried. Recrystallization from a mixed solvent of ethanol and chloroform yielded 990 mg of the titled compound as a pale yellow powder.

Provenance & Evidence