Synthesis, characterization, electropolymerization, and possible utilities of a new ruthenium-thiophene complex

ABSTRACT [RuCl2(p‐cymene)]2 was reacted with silver triflate and thiophene to give the sandwich complex [Ru(η5‐C4H4S)(η6‐p‐cymene)](PF6)2, which was characterized with NMR spectroscopy (1H‐NMR, 13C‐NMR, and 31P‐NMR), Fourier transform infrared spectroscopy, elemental analysis, and cyclic voltammetry. The behavior of this new complex in dimethyl sulfoxide with regard to the amount of absorbed water was investigated by both NMR and cyclic voltammetry; the formation of other species that affected electropolymerization was demonstrated. However, under optimal working conditions (in an anhydrous medium), the complex was successfully immobilized on a platinum electrode via an electro‐oxidation pathway through the thiophene ligand. This generated a highly stable, electroactive polymer film. Its response to the doping–undoping (charge–discharge) and redox processes, added to its high stability, promises important applications for this novel material. Moreover, this opens up the possibility of testing other compounds, such as [Ru(η5‐thiophene)(η6‐arene)], that were previously synthesized and reported for their electropolymerization and use as sensors according to their redox properties. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016, 133, 43559.