反应详情

To a solution of (2S,4R)-1-t-butoxycarbonyl-4-t-butyldimethylsilyloxy-2-hydroxymethylpyrrolidine (1.00 g) in tetrahydrofuran (20 ml) was dropwise added a 1.6 M solution of butyllithium in hexane (2 ml) at -40°~-30° C. in a nitrogen stream and the mixture was stirred at the same temperature for 30 minutes. To the reaction mixture was added ethyl bromoacetate (0.40 ml) at -40°~-30° C. and the reaction mixture was stirred at -40°~-30° C. for 30 minutes and then at ambient temperature for 3 hours. The mixture was poured into a mixture of water (50 ml) and ethyl acetate (50 ml). The organic layer was washed with brine (50 ml), dried over magnesium sulfate and concentrated under reduced pressure to give a syrup. The syrup was subjected to a column chromatography on silica gel (20 g) and eluted with chloroform to give (2S,4R)-1-t-butoxycarbonyl-4-t-butyldimethylsilyloxy-2-(ethoxycarbonylmethyloxymethyl)pyrrolidine (0.88 g).

1. stirringthe reaction mixture was stirred at -40°~-30° C. for 30 minutes
2. waitat ambient temperature for 3 hours
3. washThe organic layer was washed with brine (50 ml)
4. dry with materialdried over magnesium sulfate
5. concentrationconcentrated under reduced pressure
6. customto give a syrup
7. washeluted with chloroform