Sulfene mechanism in the pyridine-catalysed reactions of alkanesulfonyl halides with phenols

Abstract

The influence of pyridine bases upon the rate and mechanism of the interaction of alkanesulfonyl halides with phenols in organic solvents has been studied. Two competing routes have been shown to be followed under the reaction conditions, i.e. elimination-addition (the sulfene mechanism) and nucleophilic substitution at the sulfonyl group sulfur (predominantly general-base catalysis). The influence of the substrate, reactant and catalyst structure, as well as the nature of the medium, upon the rate and relationship between the competing routes have been investigated.