Acetic Acid → 1-Cyclopropyl-6,7-difluoro-8-methyl-1,4-dihydro-4-oxoquinoline-3-carboxylic acid

Participants

Reaction Steps

A mixture of ethyl 1-cyclopropyl-6,7-difluoro-1,4-dihydro-8-methyl-4-oxo-3-quinolinecarboxylate (1.97 g), concentrated sulfuric acid (1.6 ml) and acetic acid (12.8 ml) in water (9.6 ml) was refluxed for 1.5 hours. The reacting mixture was poured into ice-water (100 ml), the resulting precipitate was collected by filtration, washed with water and dried to give the title compound (1.58 g) as white powder, mp 243°-245° C.

Provenance & Evidence