Bromopalladation Triggering the Cascade Oxidative Heterocyclization Reaction of Alkynes with Alkenes in Ionic Liquids

An efficient and practical palladium-catalyzed cascade oxidative heterocyclization has been developed to afford functionalized oxygen-containing five-membered heterocycles in moderate to good yields with high regio-and diastereoselectivities.Their structures were confirmed by IR, 1 H NMR, 13 C NMR and HRMS.Furthermore, the current methodology could also be conveniently applied to the synthesis of naturally occurring biologically active functionalized tetrahydrofurans and γ-lactones frameworks.