N-Heterocyclic Carbene C,S Palladium(II) pi-Allyl Complexes: Synthesis, Characterization, and Catalytic Application In Allylic Amination Reactions

A series of five-membered N-heterocyclic carbene C,S palladium(II) pi-allyl complexes were successfully developed and characterized. Structural analyses of these complexes revealed that the organopalladium chelates adopt a skew-envelope conformation with a trans disposition of the substituents on the metal chelate rings. Utilizing these C,S palladium(II) pi-allyl complexes as catalysts, a catalytic system for the allylic amination reaction has been developed. A series of C-N bond formations between amines and unsymmetrically substituted allylic carbonates could be catalyzed efficiently by complex (+/-)-9 in a regioselective manner.