Catalytic Nucleophilic Ring Closure ofπ-Allylpalladium Intermediates

Significance

The authors describe the development of a palladium-catalyzed intermolecular ­cycloaddition that involves a nucleophliic ring closure to the central carbon of a π-allylpalladium intermediate. Spiro[2,4]heptanes are obtained in good yields and moderate diastereoselectivities using small phosphite ligands. If bulky phosphine ligands are used, a selective [4+2] cycloaddition occurs, leading to exo-methylene cyclohexane products.