Synthesis and Characterization of 2,6-Di(quinolin-8-yl)pyridines. New Ligands for Bistridentate Ru<sup>II</sup> Complexes with Microsecond Luminescent Lifetimes
作者:Michael Jäger、Lars Eriksson、Jonas Bergquist、Olof Johansson
DOI:10.1021/jo7015373
日期:2007.12.1
The synthesis of 4-substituted and 4-aryl-substituted 2,6-di(quinolin-8-yl)pyridines is described. The tridentate ligands were prepared via a palladium-catalyzed Suzuki-Miyaura cross-coupling reaction or via a one-step ring-forming reaction generating the central pyridine ring. X-ray crystal structures and H-1 NMR shifts are discussed and compared to the corresponding data for a Ru-II bistridentate complex. Intramolecular stacking of two quinoline units in the Run complex is suggested by H-1 NMR data and also observed in the X-ray structure.
Vectorial Electron Transfer in Donor-Photosensitizer-Acceptor Triads Based on Novel Bis-tridentate Ruthenium Polypyridyl Complexes
(τCSS (1 a)=140 ns, τCSS (3 a)=200 ns) formed by stepwise electrontransfer. The overall yields of charge separation (≥50 % for complex 1 a and ≥95 % for complex 3 a) are unprecedented for bis‐tridentate RuII polypyridylcomplexes. This is attributed to the long‐lived excited state of the [Ru(dqp)2]2+ complex combined with fast electrontransfer from the donor moiety following the initial charge separation