反应详情

(7S,8R)-Ethyl 8-((R)-1-phenylethylamino)-1,4-dioxaspiro[4.5]decane-7-carboxylate (7.80 g, 23.39 mmol) was dissolved in ethyl acetate (40 mL) at 25° C. with stirring. Et2O (40 mL) was then added followed by the addition of p-toluenesulfonic acid-monohydrate (4.45 g, 23.39 mmol) in one portion. Precipitation occurred almost immediately. The mixture was stirred for ½ hour, after which the precipitate was collected by filteration. The solids were rinsed with Et2O and then dried under high vacuum to yield (7S,8R)-ethyl 8-((R)-1-phenylethylamino)-1,4-dioxaspiro[4.5]decane-7-carboxylate, p-toluenesulfonic acid (10.3 g, 20.37 mmol, 87% yield) as an off-white solid. MS (ESI+)=334.30 (M+H)+.

1. customPrecipitation
2. stirringThe mixture was stirred for ½ hour
3. customafter which the precipitate was collected by filteration
4. washThe solids were rinsed with Et2O
5. customdried under high vacuum