Redox Switchable ligands suitable for transition metal ions: protonation, complexation and electrochemical properties of a ferrocene-modified tetramine diketone and its saturated analogue

New ferrocene-containing water soluble ligands were synthetized, whose protonation and coordination properties towards Ni(II) and Cu(II) were determined by potentiometric titrations. The oxidation state of Fe in the appended ferrocene influences the coordinative ability of the ligands, that can be thus electrochemically switched between different values