Controlling the Activation at Ni-CO Moieties through Lewis Acid Interactions in the Second Coordination Sphere.

Nickel complexes with a two-electron reduced CO ligand (CO , "carbonite") are investigated with regard to the influence alkali metal (AM) ions have as Lewis acids on the activation of the CO entity. For this purpose complexes with Ni(CO)AM (AM=Li, Na, K) moieties were accessed via deprotonation of nickel-formate compounds with (AM)N(Pr). It was found that not only the nature of the AM ions in vicinity to CO affect the activation, but also the number and the ligation of a given AM.