Triphenylphosphine → 2-[(4R)-4-Acetylthio-2-oxoazetidin-1-yl]-2-triphenylphosphoranylideneacetic acid p-nitrobenzyl ester

Participants

Reaction Steps

3.144 g (~1.5 equivalents) of triphenylphosphine and 12 g of poly-Hunig base are added to a solution of 3.1 g of 2-[(4R)-4-acetylthio-2-oxoazetidin-1-yl]-2-chloroacetic acid p-nitrobenzyl ester in 120 ml of dioxan and the mixture is stirred for 17 hours at 50° under nitrogen. The poly-Hunig base is filtered off, washed with dioxan and the filtrate concentrated in vacuo. The residue is chromatographed twice over silica gel with toluene and toluene/ethyl acetate (4:1 and 3:2) and yields the title compound.

Provenance & Evidence