反应详情

A solution of (2S,4R)-2-(2-fluoroethyloxymethyl)-4-methanesulfonyloxy-1-(4-nitrobenzyloxycarbonyl)pyrrolidine (4.95 g) in dimethylformamide (5 ml) was added to a mixture of thioacetic S-acid (1.26 ml) and potassium tert-butoxide (1.98 g) in dimethylformamide (25 ml) in a nitrogen stream, and the mixture was heated at 75°-80° C. for 2 hours. The mixture was poured into ice-water (100 ml) and extracted with ethyl acetate (100 ml). The extract was washed with water (100 ml×2) and brine (100 ml), in turn, dried over magnesium sulfate, and concentrated under reduced pressure to give a syrup. The syrup was subjected to a column chromatography on silica gel (80 g) and eluted with chloroform to give (2S,4S)-4-acetylthio-2-(2-fluoroethyloxymethyl)-1-(4-nitrobenzyloxycarbonyl)pyrrolidine (1.75 g).

1. temperaturethe mixture was heated at 75°-80° C. for 2 hours
2. extractionextracted with ethyl acetate (100 ml)
3. washThe extract was washed with water (100 ml×2) and brine (100 ml), in turn
4. dry with materialdried over magnesium sulfate
5. concentrationconcentrated under reduced pressure
6. customto give a syrup
7. washeluted with chloroform