Side‐on Coordination in Isostructural Nitrous Oxide and Carbon Dioxide Complexes of Nickel

A nickel complex incorporating an N2O ligand with a rare η2-N,N'-coordination mode was isolated and characterized by X-ray crystallography, as well as by IR and solid-state NMR augmented by 15N-labeling experiments. The isoelectronic nickel CO2 complex reported for comparison features a very similar solid-state structure. Computational studies revealed that η2-N2O binds to nickel slightly stronger than η2-CO2 in this case, and comparably to or slightly stronger than η2-CO2 to transition metals in general. Comparable transition state energies for the formation of isomeric η2-N,N'- and η2-N,O-complexes, and a negligible activation barrier for the decomposition of the latter likely account for the limited stability of the N2O complex.