Water → HCID 68432514, compound

Participants

Reaction Steps

In 68 ml of conc. hydrochloric acid is suspended 34 g of ethyl (R)-1-cyclopropyl-8-difluoromethoxy-7-[2-(2,2-dimethylpropanoyl)-1-methyl-2,3-dihydro-1H-5-isoindolyl]-4-oxo-1,4-dihydro-3-quinolinecarboxylate, and the suspension is heated under reflux for 3 hours, after which 340 ml of water is added to the resulting mixture and 170 ml of the solvent is removed from the mixture by distillation under atmospheric pressure over 3 hours. The reaction mixture is cooled and thereafter 17 ml of ethanol is added to the mixture, after which the crystals deposited are collected by filtration. The resulting (R)-1-cyclopropyl-8-difluoromethoxy-7-(1-methyl-2,3-dihydro-1H-5-isoindolyl)-4-oxo-1,4-dihydro-3-quinolinecarboxylic acid hydrochloride is suspended in 340 ml of water and the pH of the mixture is adjusted to 7.5 with 2 moles/liter sodium hydroxide solution, after which the crystals deposited are collected by filtration to obtain 25.55 g of (R)-1-cyclopropyl-8-difluoromethoxy-7-(1-methyl-2,3-dihydro-1H-5-isoindolyl)-4-oxo-1,4-dihydro-3-quinolinecarboxylic acid monohydrate.

Provenance & Evidence