Chemistry of Oxaziridines. 7. Kinetics and Mechanism of the Oxidation of Sulfoxides and Alkenes by 2-Sulfonyloxaziridines. Relationship to the Oxygen-Transfer Reactions of Metal Peroxides

Article abstract of DOI:10.1021/jo00372a025

A kinetic investigation of the oxidation of sulfoxides to sulfones and the epoxidation of 1-methylcyclohexene by a series of aryl-substituted 2-sulfonyloxaziridines, 5 and 9, are described.On the basis of linear free energy relationships and a qualitative frontier molecular orbital analysis, an S_N2-type mechanism is proposed that involves displacement of a substituted sulfonylimine from the oxaziridine functional group by the lone pair on the sulfur or the ?-bond of the alkene.The reaction rates are subject to both steric and electronic effects with only a minor amount of negative charge residing on the leaving group.The relationship and similarity of oxygen-transfer mechanisms for 2-sulfonyloxaziridines, metal peroxides such as the Sharpless reagent, dioxiranes, and peracids is discussed.