Abstract
130 years after Mond discovered the first homoleptic carbonyl complex Ni(CO)(4) , we report on a [Ni(CO)(4) ](.+) salt as the first synthesis of any homoleptic nickel carbonyl cation in the condensed phase. It was prepared by oxidation of nickel metal with the synergistic oxidant Ag[F{Al(OR(F) )(3) }(2) ]/0.5 I(2) (R(F) =C(CF(3) )(3) ) in CO atmosphere. This D(2d) -symmetric metalloradical represents the last missing entry among the structurally characterized homoleptic carbonyl cations of Groups 6 to 11. Additionally, the nickel tricarbonyl-nitrosyl cation [Ni(CO)(3) (NO)](+) was obtained by usage of NO[F{Al(OR(F) )(3) }(2) ] and all products were fully characterized by means of IR, Raman, NMR/EPR, single crystal and powder XRD.