Convenient synthesis of new water-soluble monosubstituted functional ferrocene derivatives

Two new water-soluble monosubstituted functional ferrocene derivatives, p-ferrocenyl benzene sulfonic acid (BSAFc) and 4-ferrocenyl-1,1′-azobenzene-3,4′-disulfonic acid (AYFc), bearing sulfonic groups and/or azo structure have been successfully synthesized in aqueous media according to the self-designed synthetic route. The preparation process is quite simple and convenient. 1H NMR, FT-IR and element analysis data demonstrated the structures of the target products. UV–Vis spectra and cyclic voltammetry (CV) measurements explained the electrophilic group that linked to BSAFc and AYFc was an influence on the orbital energy level of ferrocene. The CVs in different concentration and type of anion existing in the solution demonstrated that the electrochemical activities of BSAFc and AYFc firmly rely on the anion.