256658-01-2Relevant academic research and scientific papers
The effects of pendant vs. fused thiophene attachment upon the luminescence lifetimes and electrochemistry of tris(2,2′-bipyridine)ruthenium(II) complexes
Nurkkala, Lasse J.,Steen, Robert O.,Friberg, Henrik K. J.,Haeggstroem, Johanna A.,Bernhardt, Paul V.,Riley, Mark J.,Dunne, Simon J.
experimental part, p. 4101 - 4110 (2009/02/07)
The electrochemical and photophysical properties for a range of tris(2,2′-bipyridine)ruthenium(II) complexes in which a thiophene substituent is attached to one of the bipyridine ligands by either a pendant or a fused mode have been determined. The fused mode of attachment eliminates torsional movement between the thiophene unit and the chelating bipyridine, thereby offering optimal overlap between the ?-systems of the chelating unit and the attached thiophene unit. The electrochemical properties of these complexes were found to be similar; however, the luminescence lifetimes and intensities (in CH3CN at room temperature) were found to be correlated to the mode of attachment. The longest luminescence lifetime was observed for the complex [Ru(bpy)2{4-(thiophen-2-yl)-2,2′-bipyridine}] 2+ (3000 ns), as compared to the prototypic [Ru(bpy) 3]2+ (1745 ns). This complex also had the highest quantum yield (0.045). In the four isomeric complexes, where the thiophene ring was fused to the b or c face of the pyridine ring, the lifetimes fell in the interval 275-1510 ns, and the quantum yield ranged between 0.0047 and 0.014. Wiley-VCH Verlag GmbH & Co. KGaA, 2008.
