Synthesis and electrochemical studies of heterobinuclear zinc and molybdenum mononitrosyl complexes linked by Schiff base ligands

The reaction of 1 mol equivalent of MoCl₂(NO)T^* _p T^* _p = tris(3,5 dimethylpyrazolyl)borate] with one mole equivalent of the zinc Schiff base complexes obtained from the condensation of 2,5-dihydroxybenzaldehyde, salicylaldehyde and a series of , diamines NH₂(CH₂) _n NH₂, n = 2–4] is described, together with the i.r.; u.v.–vis. and ¹H-n.m.r. spectroscopic properties of these products. Cyclic voltammetric data in CH₂Cl₂ reveal that the binuclear complex products undergo reversible one-electron reductions associated with the MoCl(NO)T^* _p centre. No zinc-based redox processes in the new complexes could be detected on the cyclic voltammetry timescale. The behaviour of the MoCl(NO)T^* _p centre in DMSO indicates that the complexes undergo irreversible reductions at anodically shifted potentials (in comparison with the reduction of binuclear complexes in CH₂Cl₂), indicating that reductions of the binuclear complexes are solvent dependent.