(3R,4R)-4-(2,2-dimethoxyethyl)-3-[1-methyl-1-(4-nitrobenzyloxycarbonyloxy)ethyl]-azetidin-2-one → (3R,4R)-3-[1-methyl-1-(4-nitrobenzyloxycarbonyloxy)ethyl]-4-(2-oxoethyl)azetidin-2-one

Participants

Reaction Steps

A solution of (3R,4R)-4-(2,2-dimethoxyethyl)-3-[1-methyl-1-(4-nitrobenzyloxycarbonyloxy)ethyl]-azetidin-2-one (64 mg) in 80% aqueous acetic acid (3.0 ml) was heated at 50°-55° C. for 4 hours. After evaporation of the solvent, the residue was dissolved in ethyl acetate (20 ml) and the solution was washed with aqueous sodium bicarbonate. The aqueous layer was extracted with ethyl acetate (10 ml). The organic layers were combined, washed with water and brine, dried over magnesium sulfate and evaporated in vacuo to give (3R,4R)-3-[1-methyl-1-(4-nitrobenzyloxycarbonyloxy)ethyl]-4-(2-oxoethyl)-azetidin-2-one (55 mg) as a solid.

Provenance & Evidence