Synthesis and electrochemical behaviour of rigid ferrocenyl-terminated pyridylphenylene dendrimers

The synthesis of ferrocenyl-terminated pyridylphenylene dendrimers based on trifunctional core via the Diels-Alder cycloaddition of ferrocenyl-containing cyclopentadienone and ethynyl terminated phenylene derivatives is presented. Dendrimers of two generations were synthesized and characterized using NMR, MALDI-TOF spectrometry and GPC. Cyclic voltammetry (CV) of the dendrimers shows single quasi-reversible wave. The strong adsorption occurs onto Pt and GC electrodes during CV in CH2Cl2, which is reflected by the high i(pc)/(pa) ratio. Thus, a fabrication of modified Pt electrode with a ferrocenyl dendrimer is proved to be possible. The resulting electrode is stable towards CH2Cl2 washing and multiple CV scanning. The CV of the modified electrode shows an almost symmetrical response, which is typical for surface immobilized redox-active materials.