Dichloromethane → HCID 12045061, compound

Participants

Reaction Conditions

Reaction Steps

A mixture of 8-hydroxy-7-quinaldinecarboxylic acid 1 (12 g, 59 mmol) and polyphosphoric acid (30 g) in 60 ml of n-butanol is heated at 100° C. for 72 hours during which additional portions of 30 g of polyphosphoric acid and 30 ml of n-butanol are regularly added every 12 hours. After cooling to 20° C., the reaction mixture is brought to pH 4 with a 6 N potassium hydroxide solution, and then 200 ml of dichloromethane are added. The phases are separated, and the aqueous phase extracted with dichloromethane. The combined organic phases are dried over magnesium sulfate and concentrated under reduced pressure. The residue is chromatographed on a silica column, eluting with a 1/1 cyclohexane/ethyl acetate mixture so as to give 11 g (72%) of n-butyl 8-hydroxy-2-methylquinoline-7-carboxylate in the form of a white solid.

Provenance & Evidence