Ni and Cu complexes of a salen ligand bearing ferrocenes in its secondary coordination sphere.

Herein, we report the synthesis, spectroscopic characterization and electrochemical investigation of the Ni and Cu complexes of a novel Sal ligand bearing two ferrocene moieties attached at its diimine linker, M(Sal). The electronic spectra of M(Sal) are near identical to its phenyl-substituted counterpart, M(Sal), indicating the ferrocene moieties exist in the secondary coordination sphere of M(Sal). The cyclic voltammograms of M(Sal) exhibit an additional two-electron wave in comparison to M(Sal), which is assigned to the sequential oxidation of the two ferrocene moieties.