Reaction rates and thermodynamic equilibration of tetrahedral intermediates: the alcoholysis of cephalosporins

Abstract

The rate of reaction of cephalosporins with alkoxide ions shows general acid-catalysed inhibition, which is attributed to the trapping of the anionic tetrahedral intermediate (T^–) by proton donors to give the thermodynamically more stable neutral intermediate T^o at a rate which is faster than breakdown of T^–.