One-pot synthesis of 1,1′-ferrocenediylbis-(methyltriphenylphosphonium iodide) from the corresponding alcohols: Facile precursor for the construction of novel metal cations electrochemical sensors

A simple and efficient one-pot synthetic methodology for the preparation of 1,1′-ferrocenediylbis-(methyltriphenylphosphonium iodide) is described. And the obtained salt has been used for the construction of ferrocene-containing pyridine ligands 3a–b. Electrochemical investigations of 3a–b have demonstrated that upon addition of Hg2+ and Zn2+ results in large shifts of respective Fc/Fc+ redox couple to more positive potentials. Titration experiment shows that the current associated with the new redox couple increases linearly with the concentration of Hg2+ until a full equivalent has been added, which suggests that 3b is a good candidate for an amperometric sensor to detect the toxic Hg2+.