Hydrochloric Acid → HCID 14347793, compound

Participants

Reaction Steps

To ethyl 6,7-difluoro-1-(2-thienyl)-1,4-dihydro-4-oxoquinoline-3-carboxylate (0.6 g) are added 90% acetic acid (3 ml) and conc. hydrochloric acid (0.8 ml), and the mixture is refluxed for one hour. After allowing to cool, the precipitated crystals are separated by filtration, and washed with water, ethanol and ether in this order to give 6,7-difluoro-1-(2-thienyl)-1,4-dihydro-4-oxoquinoline-3-carboxylic acid (0.4 g) as colorless crystals, m.p. 245°-246° C.

Provenance & Evidence