Hydrochloric Acid → HCID 13365549, compound

Participants

Reaction Steps

A mixture of 2.83 g (0.01 mol) of 1-cyclopropyl-6,7,8-trifluoro-1,4-dihydro-4-oxoquinoline-3-carboxylic acid (II), 4.4 g (0.051 mol) of anhydrous piperazine and 30 ml of dry pyridine is refluxed for 6 hours. The solvent is stripped off in vacuo, the residue is taken up in 25 ml of water, the pH is adjusted to 1 with concentrated hydrochloric acid, while cooling with ice and, when the mixture is cold, the precipitate is filtered off under suction and washed with cold 10% strength hydrochloric acid and ethanol. After drying in vacuo at 100° C., 3.05 g of 1-cyclopropyl-6,8-difluoro-7-(piperazin-1-yl)-1,4-di- hydro-4-oxoquinoline-3-carboxylic acid hydrochloride having a decomposition temperature of 354°-355° C. are obtained.

Provenance & Evidence