Cobalt‐Catalyzed Intramolecular Cycloadditions of Alkenylidenecyclopropanes with Alkenes and Dienes

Abstract Low‐valent cobalt complexes equipped with phosphorous type of ligands can promote the intramolecular (3+2) cycloaddition of alkylidenecyclopropanes (ACPs) with alkenes and with allenes. Dienes can also be used as partners, but they afford seven‐membered cycloadducts. The reactions are fully diastereoselective and, in some cases, we also observed moderate enantioselectivities, especially when using chiral phosphite ligands.