Mononuclear Cyclometalated Ruthenium(II) Complexes of 1,2,4,5-Tetrakis(N-methylbenzimidazolyl)benzene: Synthesis and Electrochemical and Spectroscopic Studies
journal contributionposted on 11.06.2012, 00:00 by Jiang-Yang Shao, Jiannian Yao, Yu-Wu Zhong
A series of mononuclear cyclometalated ruthenium complexes with 1,2,4,5-tetrakis(N-methylbenzimidazolyl)benzene have been prepared, where two N-methylbenzimidazoles bind to the metal center and others remain intact. Electronic properties of these complexes were investigated by electrochemical and spectroscopic studies and DFT/TDDFT computations. The RuII/III redox potentials of theses complexes can be modulated by attaching substituents of various electronic natures on the non-cyclometalating ligand. These complexes display enhanced visible light absorption compared to those without two free-standing N-methylbenzimidazolyl units as a result of the three-chromophore effect.