反应详情

A solution of 2.86 g (~24 mmol) of thionyl chloride in 20 ml of dioxan is added dropwise to a suspension, stirred at room temperature, of 12 g of poly-Hunig base in a solution of 2.83 g (7.59 mmol) of 2-[(4R)-4-acetylthio-2-oxoazetidin-1-yl]-2-hydroxyacetic acid p-nitrobenzyl ester in 100 ml of dioxan. The mixture is stirred for 1.5 hours at room temperature and filtered off from the poly-Hunig base, which is subsequently washed with dioxan. The filtrate is concentrated in vacuo. The 2-[(4R)-4-acetylthio-2-oxoazetidin-1-yl]-2-chloroacetic acid p-nitrobenzyl ester obtained is used in the next stage in crude form.

1. filtrationfiltered off from the poly-Hunig base, which
2. washis subsequently washed with dioxan
3. concentrationThe filtrate is concentrated in vacuo