Process for preparing 3-exomethylenecepham sulfoxides.

摘要

A process for preparing a 3-exomethylenecepham sulfoxide ester of the formula 2; …… wherein R is the residue of a carboxylic acid and R1 is a carboxylic acid protecting group, which process comprises:… (a) mixing under anhydrous conditions in an inert organic solvent a 2-chlorosulfinylazetidin-4-one of the formula 1: …… with stannic chloride in the presence of an oxygen compound selected from the group consisting of ……