Water → HCID 54485418, compound

Participants

Reaction Steps

Ozonised oxygen was bubbled through a solution of p-methoxybenzyl 2[(3S, 4R)-4-acetylthio-3-bromo-2-oxoazetidin-1-yl]-3-methylbut-2-enoate (Osborne N. F. et al., J. Chem. Soc. Perkin Trans. 1, 1994, 179) (20.16 g, 0.0456 mol) in ethyl acetate (400 ml) at -65° to -70° C. until a permanent blue solution was obtained. Excess ozone was removed by the passage of oxygen, then trimethyl phosphite (53.8 ml, 0.456 mol) was added dropwise. After 15 min. the solution was allowed to warm to room temperature, then stood for 16 hr. The solvents were evaporated and the residue reevaporated twice from toluene, then dissolved in ethyl acetate (300 ml) and stirred vigorously for 1.5 hr. with a solution of p-toluenesulphonic acid (2 g) in water (100 mol). After dilution with water the organic layer was separated and the aqueous layer further extracted with ethyl acetate. The combined extracts were washed successively with saturated aq. sodium hydrogen carbonate and brine, then dried ((MgSO4) and evaporated. Purification by flash chromatography (silica, ethyl acetate-pet. ether) gave the product as a light brown oil, yield 10.6 g (58%).

Provenance & Evidence