Structure, spectroscopy and electrochemistry of the bis(2,2′-bipyridine)(salicylato)ruthenium(II) complex

Abstract

The bis(2,2′-bipyridine)(salicylato)ruthenium(II) complex has been prepared and characterized by means of single crystal X-ray diffraction, electrochemistry and resonance Raman spectroscopy. The electronic bands in the visible region have been assigned to Ru–bipy charge-transfer transitions and discussed in terms of ZINDO/S semiempirical calculations. Spectroelectrochemical measurements have been performed in order to elucidate the nature of the electrochemical waves in the cyclic voltammograms. The green complex generated by oxidation of the complex at 0.25 V has been isolated, revealing substantial ruthenium–salicylate electronic mixing, as deduced from the corresponding resonance Raman spectra. Further oxidations at 1.2 and 1.4 V have been observed and ascribed to hydroxylation of the salicylate semiquinone ligand in the complex.

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