One-Step Synthesis of 4,4′-Dicyano-2,2′-bipyridine and Its Bis(4,4′-di-tert-butyl-2,2′-bipyridine)ruthenium(II) Complex

This report describes a new route for the fast, economical and effective one-step synthesis and facile workup procedure of 4,4'-dicyano-2,2'-bipyridine (dnbpy) and its corresponding ruthenium complexes. The complex [(tbbpy)(2)Ru(dnbpy)]-(PF6)(2) was prepared for the first time (tbbpy = 4,4'-di-tert-butyl-2,2'-bipyridine) and the solid-state molecular structure was investigated with the help of a single-crystal X-ray analysis. The influence of the dnbpy ligand on the metal-to-ligand charge-transfer (MLCT) processes of the complex was studied. The compound shows two absorption maxima in the MLCT region of the UV/Vis spectrum at 418 and 5 10 nm and the emission is 116 nm redshifted in comparison to that of [(tbbpy)(3)Ru](PF6)(2). ((c) Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2008)