The synthesis of an air-stable series of Pd0 complexes with unsymmetric bidentate N-pyridine N-heterocyclic carbene ligands has been described. The carbenes were generated by synthesis of the silver(I) complexes from the imidazolium salts, followed by transmetallation of the C-N ligands to obtain the target electron-rich zerovalent palladium compounds. The bidentate coordination behaviour of the ligands was confirmed by 1H, 13C NMR and X-ray spectroscopy. The complexes are active precatalysts for the selective transfer semihydrogenation of alkynes to Z-alkenes, with selectivities up to 99%. Copyright © 2011 John Wiley & Sons, Ltd.