N-nitropropionamide, EtC(O)NHNO2, oxidatively adds to Ir(Cl)(N-2)(PPh3)(2) to give a eta(2)-(N,O)-N-nitropropionamide anion bound to an Ir hydride complex. Single-crystal X-ray diffraction of the product indicates that it forms an unusual 0:bound chelate through the nitro group. Density functional calculations for a model nickel complex, [Ni(MeC(O)NNO2)(CN)(2)](-), are used to help distinguish the observed IR bands for the four possible conformations and binding geometries of this ligand.