Hydrochloric Acid → 1-Cyclopropyl-6,7-difluoro-5-methyl-4-oxo-1,4-dihydroquinoline-3-carboxylic acid
Reaction equation
Cl.[CH:2]1([N:5]2[C:14]3[C:9](=[C:10]([CH3:17])[C:11]([F:16])=[C:12]([F:15])[CH:13]=3)[C:8](=[O:18])[C:7]([C:19]([O:21]CC)=[O:20])=[CH:6]2)[CH2:4][CH2:3]1>C(O)(=O)C>[CH:2]1([N:5]2[C:14]3[C:9](=[C:10]([CH3:17])[C:11]([F:16])=[C:12]([F:15])[CH:13]=3)[C:8](=[O:18])[C:7]([C:19]([OH:21])=[O:20])=[CH:6]2)[CH2:3][CH2:4]1Participants
4
Reactant 2
Product 1
Reagents, catalysts & solvents 1
Procedure
20 ml of 90% acetic acid and 5 ml of concentrated hydrochloric acid were added to 1.9 g of ethyl 1-cyclopropyl-6,7-difluoro-5-methyl-1,4-dihydro-4-oxoquinoline-3-carboxylate, followed by refluxing for 2 hours. After cooling, the crystals precipitated were collected by filtration and washed with water, followed by washing with ethanol and then with diethyl ether to give 1.6 g of 1-cyclopropyl-6,7-difluoro-5-methyl-1,4-dihydro-4-oxoquinoline-3-carboxylic acid.