Chiral Palladium Bis(acyclic diaminocarbene) Complexes as Enantioselective Catalysts for the Aza-Claisen Rearrangement

Palladium complexes of chiral bis(acyclic diaminocarbene) ligands with seven-membered chelate rings catalyze the aza-Claisen rearrangement of an allylic benzimidate to an allylic amide with moderate yields and enantioselectivities of 30–59% ee. The promotion of electrophilic catalysis by complexes of these ligands highlights their distinct stereoelectronic properties relative to those of common bis(N-heterocyclic carbenes).