反应详情

To a solution of (2S,4R)-1-benzyloxycarbonyl-2-carboxymethyloxymethyl-4-methanesulfonyloxypyrrolidine (79.4 g), 2,2-dimethyl-1,3-dioxane-4,6-dione (29.55 g) and 4-(dimethylamino)pyridine (25.05 g) in dichloromethane (635 ml) was added 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide (39.3 g) at 5°-10° C. The solution was stirred at the same temperature for one hour and at ambient temperature for 18 hours. The mixture was washed with water (650 ml), 1N hydrochloric acid (650 ml), saturated aqueous sodium hydrogen carbonate (650 ml), and brine (650 ml) successively, dried over magnesium sulfate, and concentrated under reduced pressure to give a syrup. The syrup was subjected to a column chromatography on silica gel (800 g) and eluted with a mixture of methanol and dichloromethane (2:98 V/V) to give (2S,4R)-1-benzyloxycarbonyl-2-[2-(2,2-dimethyl-4,6-dioxo-1,3-dioxan-5-yl)-2-oxoethyl]oxymethyl-4-methanesulfonyloxypyrrolidine (80.98 g).

1. washThe mixture was washed with water (650 ml), 1N hydrochloric acid (650 ml), saturated aqueous sodium hydrogen carbonate (650 ml), and brine (650 ml) successively
2. dry with materialdried over magnesium sulfate
3. concentrationconcentrated under reduced pressure
4. customto give a syrup
5. washeluted with a mixture of methanol and dichloromethane (2:98 V/V)