A Study of Alkene Disulfonoxylation

We have developed convenient protocols for alkene disulfonoxylation, which involve stirring alkene substrate with a commercial I(III) oxidant and sulfonic acid in CH2Cl2 at ambient temperature. The reactions can be performed open to air without any special precautions to exclude moisture and, in most cases, deliver the products of vicinal disulfonoxylation. Where relevant, the reactions are stereospecific and furnish the products of syn-disulfonoxylation. Our protocols work best with terminal alkene substrates, but other substitution patterns are also compatible. With alkene substrates bearing appropriately positioned esters, sulfonoxylated lactones are the major products. With certain styrenyl alkenes, the products of geminal disulfonoxylation are exclusive. For this last reaction type, our results suggest that literature reports of related transformations contain misassigned product structures.