Intriguing formal [2+3] cycloaddition promoted by a hypervalent iodine reagent

Treatment of various substituted phenols in the presence of iodobenzene diacetate, perfluorinated alcohols and furan, allylsilanes or cyclic enol ethers promotes an oxidative annulation process in moderate to useful yields. In only one step, this method produces different heterocyclic rings such as dihydrofuranobenzofurans, tetrahydrofuranobenzofurans, tetra hydropyranofurans, and dihydrobenzofurans. (C) 2008 Elsevier Ltd. All rights reserved.