Synthesis, characterization and electrochemical recognition of metal ions of three new ferrocenyl derivatives containing pyridyl moiety

Abstract

Three new ferrocene (Fc) based receptors with pyridyl moiety, named methyl-6-ferrocenoylacetyl-2-pyridine carboxylate (FcL1), 1,1′-(2,6-bispyridyl)bis-3-ferrocenyl-1,3-propanedione (FcL2), ferrocenecarboxaldehyde-2,6-dipicolinoyhydrazone (FcL3) were synthesized, and further characterized by elemental analysis, IR spectra, UV-Vis spectra, 1H and 13C NMR. The electrochemical properties and ion sensing properties of FcL1, FcL2 and FcL3 were also investigated by means of cyclic voltammetry in ethanol solution with 0.1 mol/L LiClO4 as the supporting electrolyte. The E0 values of the receptors increase with the scanning rate increasing at high scanning rate, and Ipa/Ipc approaches unity, indicating that the redox reaction is basically reversible. Their recognition performances to different metal cations such as Cd(II), Co(II), Cu(II), Hg(II), Mn(II), Ni(II), Zn(II) show that the FcL1 is responsive to Cu(II) with the maximum electrochemical shift of the FcL1 for Cu(II) of about 72.0 mV, whereas the FcL2 is responsive to Cu(II) and Mn(II) with shift of 102 mV and 109 mV, respectively, and the FcL3 is responsive to Hg(II) and Mn(II) with the shift of 53.0 mV and 54.0 mV, respectively. All the results show that these receptors may have potential applications in electrochemical sensor technology, material science, and molecular devices.