A series of three chiral, expanded six-membered NHC–palladium (II) complexes was prepared with successively increased sterical demand, while retaining natural d-(+)- camphor as a chiral motif. The catalysts showed different reaction profiles in the asymmetric, intramolecular α-arylation of amides. The molecular structure of two N-heterocyclic and one nitrogen acyclic carbene palladium isonitrile complex was unequivocally determined by X- ...