Binding of carbon monoxide at a single nickel center and its oxidative reactivity toward CO2 and O2

Abstract

AbstractA nickel(0) monocarbonyl complex (1‐CO) supported by a neutral tridentate PP2 ligand reveals significant stability toward CO2, which is clearly different from its analogous nickel monocarbonyl species supported by an anionic PNP ligand. Although both nickel(0)‐CO species possess a similar distorted tetrahedral geometry, the nickel site in 1‐CO is well protected by three phosphorus donors, while (NP2)Ni(CO) possesses a nickel center having a site trans to the amide donor for effective CO2 binding. The current study shows that the structural preference of a tridentate ligand dictates nickel's reactivity toward CO2. Its oxygenation by O2(g) results in the formation of a nickel(II) carbonate species, which is followed by generating phosphine oxide.