p-Toluenesulfonic acid monohydrate → (3S,5S,6R,8S)-8-Allyl-5-(4-chloro-3-fluorophenyl)-6-(3-chlorophenyl)-3-cyclopropyl-8-methyl-2,3,5,6,7,8-hexahydrooxazolo[3,2-a]pyridin-4-ium 4-methylbenzenesulfonate

Participants

Reaction Steps

p-Toluenesulfonic acid monohydrate (30.3 g, 159 mmol, Aldrich, St. Louis, Mo.) was added to a solution of (3S,5R,6S)-3-allyl-6-(4-chloro-3-fluorophenyl)-5-(3-chlorophenyl)-1-((S)-1-cyclopropyl-2-hydroxyethyl)-3-methylpiperidin-2-one (73.6 g, 154 mmol) in toluene (386 mL). The reaction mixture was heated at reflux using a Dean-Stark apparatus. After 4 hours, the reaction was cooled and concentrated under reduced pressure to provide the title compound as a pale yellow syrup. The crude product was used in next step without further purification.

Provenance & Evidence