Palladium(II)-Catalyzed Intermolecular Cascade Cyclization of Methylenecyclopropanes with Aromatic Alkynes: Construction of Spirocyclic Compounds Containing Indene and 1,2-Dihydronaphthalene Moieties

A palladium(II)-catalyzed intermolecular cascade cyclization of methylenecyclopropanes with aromatic alkynes is reported in this paper. The reaction involves a migratory insertion of alkyne, an intramolecular Heck-type reaction, and beta-H elimination, providing a series of spirocyclic compounds containing indene and 1,2-dihydronaphthalene moieties in moderate to excellent yields upon heating.