Formation of N2O from a nickel nitrosyl: Isolation of the cis -[N2O2]2- intermediate

Article abstract of DOI:10.1021/ja304204q

Addition of 2,2′-bipyridine (bipy) to [Ni(NO)(bipy)][PF₆] (1) results in formation of a rare five-coordinate nickel nitrosyl [Ni(NO)(bipy)₂][PF₆] (2). This complex exhibits a bent NO^- ligand in the solid state. On standing in acetonitrile, 2 furnishes the NO coupled product, [Ni(κ²-O₂N ₂)(bipy)] (8) in moderate yield. Subsequent addition of 2 equiv of acetylacetone (H(acac)) to 8 results in formation of [Ni(acac) ₂(bipy)], N₂O, and H₂O. Preliminary mechanistic studies suggest that the N-N bond is formed via a bimetallic coupling reaction of two NO^- ligands.