Hydrochloric Acid → HCID 19358312, compound

Participants

Reaction Conditions

Reaction Steps

In 10 ml of methylene chloride was suspended 0.28 g of ethyl 1-cyclopropyl-8-difluoromethoxy-7-[7-methoxy-2-(p-toluenesulfonyl)isoindolin-5-yl]-1,4-dihydro-4-oxoquinoline-3-carboxylate, and the suspension was cooled to -30° C., after which 1.3 ml of 1.0 M solution of boron tribromide in methylene chloride was added dropwise thereto over a period of 5 minutes, and the resulting mixture was stirred at 0° C. for 2 hours. The reaction mixture was added to a mixed solvent of 10 ml of chloroform and 10 ml of water, and the organic layer was separated. The organic layer obtained was washed with water, dried over anhydrous magnesium sulfate, and then distilled under reduced pressure to remove the solvent. The resulting residue was purified by a column chromatography (eluent; chloroform:acetone=5:1) and the crystals thus obtained were suspended in 1.5 ml of ethanol and 1.5 ml of dioxane, after which 0.74 ml of a 1N aqueous sodium hydroxide solution was added thereto and the resulting mixture was stirred at 60° C. for 30 minutes. To the reaction mixture was added 0.74 ml of 1N hydrochloric acid and the crystals were collected by filtration to obtain 0.12 g of light-brown 1-cyclopropyl-8-difluoromethoxy-7-[7-hydroxy-2-(p-toluenesulfonyl)isoindolin-5-yl]-1,4-dihydro-4-oxoquinoline-3-carboxylic acid.

Provenance & Evidence