The effect of d-block metal complexation on the spectroscopic and redox properties of ferrocene derivatives containing pyridine ligands

Three ferrocene derivatives 1–3, each containing two pyridine ligands, form complexes with a variety of d-block metals, as evidenced by NMR and UV–vis spectroscopy and cyclic voltammetry. The X-ray crystal structures of 1 and its Mo(0) complex are reported. The Zn(II) and Cu(I) complexes of 1–3 have a 2/1 (ligand/metal) stoichiometry. The factors influencing the changes in the redox and chromogenic properties of these ligands upon complexation are discussed.