反应详情

To a solution of (2S,4R)-2-(2-hydroxyethyloxymethyl)-4-methanesulfonyloxypyrrolidine (30.5 g) in a mixture of tetrahydrofuran (120 ml) and water (120 ml) was dropwise added a solution of allyl chloroformate (14.5 ml) in tetrahydrofuran (14.5 ml) under ice-cooling with stirring, keeping the pH between 9-10 with 4N aqueous sodium hydroxide. The mixture was stirred at the same condition for one hour and extracted with ethyl acetate (200 ml). The organic layer was dried over magnesium sulfate and evaporated under reduced pressure to give a syrup. The syrup was subjected to a column chromatography on silica gel (400 g) and eluted with a mixture of methanol and dichloromethane (2:98 V/V) to give (2S,4R)-1-allyloxycarbonyl-2-(2-hydroxyethyloxymethyl)-4-methanesulfonyloxypyrrolidine (28.03 g).

1. temperaturecooling
2. stirringThe mixture was stirred at the same condition for one hour
3. extractionextracted with ethyl acetate (200 ml)
4. dry with materialThe organic layer was dried over magnesium sulfate
5. customevaporated under reduced pressure
6. customto give a syrup
7. washeluted with a mixture of methanol and dichloromethane (2:98 V/V)