反应详情

To a solution of allyl (4R)-4-[(2R,3S)-3-{(1R)-1-t-butyldimethylsilyloxyethyl}-4-oxoazetidin-2-yl]-3-oxopentanoate (6.52 g) and triethylamine (6.8 ml) in acetonitrile (50 ml) was added a lM solution (17 ml) of p-toluenesulfonyl azide in acetonitrile at 0°-5° C. and the mixture was stirred at the same temprature for 2 hours. The mixture was concentrated under reduced pressure to give a residue. The residue was triturated with hexane. The precipitates were filtered off. The filtrate was concentrated under reduced pressure to give a syrup. The syrup was subjected to a column chromatography on silica gel (80 g) and eluted with a mixture of ethyl acetate and hexane (1:9 V/V) to give allyl (4R)-2-diazo-4-[(2R,3S)-3{(1R)-1-t-butyldimetylsilyloxyethyl}-4-oxoazetidin-2-yl]-3-oxopentanoate (3.78 g).

1. concentrationThe mixture was concentrated under reduced pressure
2. customto give a residue
3. customThe residue was triturated with hexane
4. filtrationThe precipitates were filtered off
5. concentrationThe filtrate was concentrated under reduced pressure
6. customto give a syrup
7. washeluted with a mixture of ethyl acetate and hexane (1:9 V/V)