Chlorine → HCID 56624834, compound

Participants

Reaction Conditions

Reaction Steps

To a solution of methyl 3-methyl-2-[(3S,4R)-4-methylthio-3-{(1R)-1-(p-nitrobenzyloxycarbonyloxy)-ethyl}-2-oxoazetidin-1-yl]but-2-enoate (481 mg) in dichloromethane (5 ml) was added a solution of chlorine (83 mg) in carbon tetrachloride (0.65 ml) at -78° C. The solution was allowed to warm to 0° C. during 45 minutes and evaporated in vacuo. The residue was chromatographed on silica gel (12 g) eluting with 10-33% ethyl acetate in hexane to give methyl 2-[(3S)-4-chloro-3-{(1R)-1-(p-nitrobenzyloxycarbonyloxy)-ethyl}-2-oxoazetidin-1-yl]-3-methylbut-2-enoate [a mixture (55:45) of (4R) isomer and (4S) isomer] (394 mg).

Provenance & Evidence