Studies of Allylic Substitution Catalysed by a Palladium Complex of a C2‐Symmetric Bis(aziridine): Preparation and NMR Spectroscopic Investigation of a Chiral π‐Allyl Species

The chiral palladium π‐allyl intermediate for the catalytic asymmetric synthesis shown in Scheme 1 has been isolated as the PF salt. MM 2 calculations have been performed and the structure of the palladium complex in solution has also been investigated by means of NMR spectroscopy. Both the computational and spectroscopic results suggest that in the complex the bidentate bis(aziridine) ligand adopts a conformation that forces the π‐allyl moiety out of the normally preferred square‐planar geometry. This nicely explains the very high enantioselectivity observed in the title reaction.