反应详情

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.

1. temperaturewas heated
2. temperatureunder reflux for 1.5 hours
3. temperatureto cool
4. filtrationThe precipitated crystals were collected by filtration
5. washwashed with water and ethanol
6. customdried
7. customRecrystallization from a mixed solvent of ethanol and chloroform