A simple PdCl2/O2/DMF catalytic system for highly regioselective cyclotrimerization of olefins with electron-withdrawing groups

A highly regioselective cyclotrimerization of olefins with electron-withdrawing groups in a PdCl2/O2/DMF catalytic system is disclosed, and a possible mechanism has also been proposed, which reveals the PdCl2-catalyzed cyclotrimerization of olefins with electron-withdrawing groups goes through a quite different pathway from that of alkynes.