Sodium Hydroxide → 4-[3-(3-Chloro-6-methoxyquinolin-4-yl)-3-(r,s)-fluoropropyl]-1-[2-(2,5-difluorophenylthio)ethyl]-piperidine-4-carboxylic acid

Participants

Reaction Conditions

Reaction Steps

A mixture of 0.07 g of methyl 4-[3-(3-chloro-6-methoxyquinolin-4-yl)-3-(R,S)-fluoropropyl]-1-[2-(2,5-difluorophenylthio)ethyl]piperidine-4-carboxylate in 3 cm3 of dioxane, 3 cm3 of methanol and 0.9 cm3 of aqueous 5N sodium hydroxide solution was maintained at a temperature in the region of 70° C. for 4 hours. After cooling to about 20° C., the reaction mixture was concentrated to dryness under reduced pressure (2 kPa) at a temperature in the region of 40° C. The residue was chromatographed under atmospheric pressure, on a column of silica gel (particle size 70-200μ; mass 10 g), eluting with a dichloromethane/methanol/aqueous ammonia mixture (40/5/0.5 by volume). Fractions 10 to 15 were combined and then concentrated to dryness under the same conditions as above. 0.04 g of 4-[3-(3-chloro-6-methoxyquinolin-4-yl)-3-(R,S)-fluoropropyl]-1-[2-(2,5-difluorophenylthio)ethyl]-piperidine-4-carboxylic acid was obtained in the form of a white solid.

Provenance & Evidence