title: Derivatization of bichromic cyclometalated Ru(II) complexes with hydrophobic substituents.
abstract: The syntheses and physical properties of cyclometalated Ru(II) complexes containing a triphenylamine (TPA) unit bearing aliphatic groups are reported. Each member of the series consists of an octahedral Ru(II) center coordinated by a tridentate polypyridyl ligand and a tridentate cyclometalating ligand. One of the chelating ligands contains electron-deficient methyl ester groups, while a TPA unit is attached to the central ring of the adjacent chelating ligand through a thiophene bridge. This study builds on our previous work (Inorg. Chem. 2011, 50, 6019-6028; Inorg. Chem. 2011, 50, 5494-5508) by (i) outlining a synthetic protocol for installing aliphatic groups on the TPA substituents, (ii) examining the role that terminal -O-hexyl and -S-hexyl groups situated on the TPA  have on the electrochemical properties, and (iii) demonstrating the potential benefit of installing the TPA on the neutral chelating ligand rather than the anionic chelating ligand. The results reported herein provide important synthetic advances for our broader goal of developing bis-tridentate cyclometalated Ru(II) complexes for light-harvesting applications.
authors.affiliation: Department of Chemistry, Institute for Sustainable Energy, Environment and Economy, and Centre for Advanced Solar Materials, University of Calgary, 2500 University Drive Northwest, Calgary, Alberta, Canada T2N 1N4.
authors.forename: Kiyoshi C D
authors.initials: KC
authors.lastname: Robson
authors.forename: Bryan D
authors.initials: BD
authors.lastname: Koivisto
authors.forename: Curtis P
authors.initials: CP
authors.lastname: Berlinguette
mesh_terms: D003500:Cyclization; D004563:Electrochemistry; D008024:Ligands; D009682:Magnetic Resonance Spectroscopy; D017975:Ruthenium Compounds / Q000737:chemistry*; D021241:Spectrometry, Mass, Electrospray Ionization
chemical_list: D008024:Ligands; D017975:Ruthenium Compounds