Ruthenium(II) complexes incorporating tridentate Schiff base ligands: synthesis, spectroscopic, redox, catalytic and biological properties

A series of new diamagnetic ruthenium(II) complexes of the type (RuCl(CO)(B)(L)) (where B = PPh3, AsPh3 or Py; L = monobasic tridentate Schiff base ligands derived from o-aminophenol or o-aminothiophenol with ethylacetoacetate or ethylbenzoylacetate) have been synthesized and these complexes were characterized by physico-chemical and spectroscopic methods. Cyclic voltammograms of all the complexes show quasi-reversible oxidation in the range 0.24-1.05V and the quasi-reversible reduction in the range -0.14 to -0.51 V. The observed redox potentials show little variation with respect to the replacement of triphenyl phosphine/arsine by pyridine. The complexes were tested as catalysts in the oxidation of primary and secondary alcohols using molecular oxygen at room temperature and also in C-C coupling reactions. Further, the antibacterial properties of the free ligands and their metal complexes were evaluated against certain bacteria such as Escherichia coli and Staphylococcus aureus. Copyright (C) 2010 John Wiley & Sons, Ltd.