Facile and controllable synthesis of multiply substituted benzenes via a formal [3+3] cycloaddition approach

A facile direct [3+3] approach for the conversion of α,β-unsaturated carbonyls to multi-substituted benzenes using allylic phosphonium ylide reagents has been developed. The substituents and their positions on the benzene ring are controllable and predictable by the choice of an appropriate combination of α,β-unsaturated carbonyl compounds and ylides.