Beer, Paul D. and Dent, Simon W. and Fletcher, Nicholas C. and Wear, Trevor J. (1996) Anion and cation recognition by new mono- and bis-ruthenium(II) bipyridyl crown ether receptor molecules. Polyhedron, 15 (18). pp. 2983-2996. ISSN 0277-5387
Full text not available from this repository.Abstract
Novel aza crown and dibenzocrown ether mono-and bis-ruthenium(II) bipyridyl amide-containing receptors have been synthesized and their preliminary Group 1 metal cation and halide anion complexing properties investigated. 1H NMR coordination studies have shown the receptors bind potassium cations in their respective crown ether recognition sites. Chloride anion coordination studies reveal that those receptors containing secondary amide CO - NH groups can complex and electrochemically sense chloride anions through a combination of electrostatic attraction and favourable amide CO - NH - anion hydrogen bonding interactions. Stability constant determinations from NMR titration data and electrochemical observations suggest, with receptor [Ru2L6(bipy)4][PF6]4, aza crown ether complexed potassium cations in combination with an amide-linked positively charged ruthenium(II) bipyridyl moiety can cooperatively enhance the strength of chloride anion complexation. In addition, fluorescence emission spectral studies show that the relative emission intensities of the metal-to-ligand charge transfer emission bands of the secondary amide-containing receptors are increased in the presence of chloride anions.