Reactions of cephalosporin sulphones 2. Rearrangement of 2α- bromocephem sulphones to pyrroles

Article abstract of DOI:10.1016/S0040-4020(98)00316-0

2α-Bromocephem sulphones exhibit two different rearrangements in acetonitrile solution: first, the tendency for elimination of the bromine as a bromonium ion leads to its formal movement to the para position of the 7β- aromatic ring. Secondly, a bromopyrrole derivative may also form, which can possibly be attributed to an unusual Ramberg-Backlund-like rearrangement followed by bromination.