Palladium(0)-Catalyzed Intramolecular Cascade Cyclization of Methylenecyclopropanes.

A Pd(0)-catalyzed cascade cyclization of methylenecyclopropanes (MCPs) involving an intramolecular Heck-type reaction and β-H eliminations has been disclosed in this paper. The reaction proceeds smoothly through an unprecedented ring-opening pattern of MCPs via a cyclopropene intermediate and a vinylpalladium carbene species seemingly, furnishing spirocyclic compounds containing fluorene and 1,2-dihydronaphthalene moieties in moderate to good yields.