Unprecedented Ligand Dependent SN2′ Mechanism on the Palladium-catalyzed Nucleophilic Substitution to Bicyclic Dienyl Acetates

Palladium-catalyzed nucleophilic reaction to bicyclic dienyl acetates 1 was studied with both optically active substrates and deuterium labeled substrates in order to clarify regioselectivity of the reaction. The regioselectivity depended on phosphine ligands. Thus, SN2 type reaction was observed using PPh3. Whereas, unprecedented SN2′ type reaction proceeded in high yields using DPPP and DPPB, which is applicable to a remote nucleophilic substitution.