Palladium‐Catalyzed [3+2] Cycloaddition of Activated Butadienylcyclopropanes

Abstract The activated butadienylcyclopropane has been successfully developed as a new precursor of the Pd‐π‐allyl zwitterion for the Pd‐catalyzed intermolecular [3+2] cycloaddition, which proceeds preferentially over its intramolecular rearrangement into a vinyl cyclopentane. Multi‐substituted cyclopentanes bearing a butadienyl group are synthesized through the Pd‐catalyzed [3+2] cycloaddition reaction of activated butadienylcyclopropanes with methylenemalononitrile derivatives in high yield under mild conditions. The cycloaddition reaction could proceed well on a gram scale.