Binuclear mixed-metal complexes formed by nickel(II) and other 3d bivalent ions with tripod ligands

Abstract

Reaction of the five-co-ordinate [Ni(NP3)X]X complexes [NP3= tris(2-diphenylphosphinoethyl)amine; X = Cl, Br, I] with MX2 salts (M = Fe, Co, Ni, Zn) gives complexes of general formula NiM(NP3)X4. Spectrophotometric, conductometric, and far-i.r. data suggest for these complexes a binuclear non-ionic structure consisting of a square-planar ‘core’ with a NiNP2X chromophore, and a pseudo-tetrahedral ‘core’ with a MPX3 chromophore. The analogous nickel–manganese complexes undergo selective oxidation with formation of a phosphine oxide, probably bonded to MnII.