Water → 2-[(2-Fluoro-5-trifluoromethoxyphenyl)(1-methylpiperidin-4-yloxy)methyl]pyridine

Participants

Reaction Conditions

Reaction Steps

A mixture of (2-fluoro-5-trifluoromethoxyphenyl)pyridin-2-ylmethanol (340 mg) and 4-hydroxy-1-methylpiperidine (273 mg) in methanesulfonic acid (1.5 mL) is heated in a sealed tube at 145° C. for 24 hours and then at 155° C. for 7 hours. The mixture is cooled back to room temperature, poured into water which is then made alkaline with concentrated sodium hydroxide solution. The aqueous phase is extracted with diethyl ether. Pooled extracts are dried over magnesium sulphate and concentrated under reduced pressure. The residue is purified by column chromatography over silica gel (gradient dichloromethane/methanol/ammonia from 95/5/0.5 to 90/10/0.5) to afford the pure base that is then converted into its dioxalate salt in acetone to give 2-[(2-fluoro-5-trifluoromethoxyphenyl)(1-methylpiperidin-4-yloxy)methyl]pyridine, dioxalate melting at 45° C.

Provenance & Evidence