Hydrochloric Acid → 1-Cyclopropyl-8-(difluoromethoxy)-7-(1-methyl-2,3-dihydro-1H-isoindol-5-yl)-4-oxo-1,4-dihydroquinoline-3-carboxylic acid

Participants

Reaction Steps

In 4 ml of ethanol was suspended 1.00 g of ethyl (-)-1-cyclopropyl-8-difluoromethoxy-7-(1-methyl-2-tritylisoindolin-5-yl)-1,4-dihydro-4-oxoquinoline-3-carboxylate, followed by adding thereto 0.26 ml of 6N hydrochloric acid, and the resulting mixture was stirred at room temperature for 30 minutes. The reaction mixture was filtered, after which 0.75 ml of a 5N aqueous sodium hydroxide solution was added to the filtrate and the resulting mixture was stirred at room temperature for 1 hour. To the reaction mixture was added 16 ml of water, followed by filtration. Carbon dioxide was bubbled into the filtrate and the crystals were collected by filtration to obtain 0.56 g of light-yellow (-)-1-cyclopropyl-8-difluoromethoxy-7-(1-methyl-isoindolin-5-yl)-1,4-dihydro-4-oxoquinoline-3-carboxylic acid.

Provenance & Evidence