Oxidative cyclizations of oximes using hypervalent iodine reagents

This account overviews oxidative cyclization reactions of aldoximes or ketoximes promoted by hypervalent iodine reagents. The oxidation of aldoximes by iodine(III) compounds generates nitrile oxides which can further react with appropriate substrates via intermolecular or intramolecular 1,3-dipolar cycloaddition reactions leading to a variety of nitrogen and oxygen heterocycles. Hypervalent iodine reagents can also react with ketoximes producing the corresponding heterocyclic products via intramolecular cyclization reactions. Recently, the oxidative cyclization reactions of aldoximes have been realized under catalytic conditions mediated by hypervalent iodine active species.