Redox And Electronic Properties of New Tetrazole-Based Ruthenium Complexes.

The design and investigation of new transition metal complexes are still of particular interest both for the investigation of intramolecular electron transfer processes, under carefully controlled geometry, and their potential applications as molecular devices.1 Mono and polynuclear complexes are appealing as systems for optoelectronic molecular devices, conversion of light into electricity or chemical energy and electrochemical and luminescent molecular recognition. Ruthenium complexes with heterocycles ligands, bearing uncoordinated nitrogen atoms, have proved to be particularly interesting for applications as sensing materials towards substrates ranging from molecular and ionic species to DNA, to probe both structural and functional aspects of nucleic acid chemistry.2,3 In this respect, the electronic properties of the metal complex must be properly tuned in order to obtain a positive interaction between the probe and substrate, for getting an efficient trasducing signal. In this communication we report the electrochemical, UV-Vis-NIR spectroelectrochemical and electrochemiluminescence behaviour of a class of new polypyridyl ruthenium species containing tetrazole-based ligands which appear to be very promising for the development of electrochemical sensors and biosensors. References: 1) V. Balzani, A. Juris, M. Venturi, S. Campagna, S. Serroni, Chem. Rev. 96, 1996, 759. 2) T. G. Drummond, M. G. Hill, J. K. Barton, Nature Biotech., 21, 2003, 1192. 3)K. E. Erkkila, D. T. Odom, J. K. Barton, Chem. Rev., 99, 1999, 2777.