title: Affinity capillary electrophoresis and density functional theory employed for the characterization of hexaarylbenzene-based receptor complexation with alkali metal ions.
abstract: In this study, affinity capillary electrophoresis (ACE) and quantum mechanical density functional theory (DFT) calculations were combined to investigate non-covalent binding interactions between the hexaarylbenzene-based receptor (R) and alkali metal ions, Rb(+) and Cs(+) , in methanol. The apparent binding (stability) constants (K(b) ) of the complexes of receptor R with alkali metal ions in the methanolic medium were determined by ACE from the dependence of effective electrophoretic mobility of the receptor R on the concentration of Rb(+) and Cs(+) ions in the BGE using a non-linear regression analysis. The receptor R formed relatively strong complexes both with rubidium (log K(b) =4.04±0.21) and cesium ions (log K(b) =3.72±0.22). The structural characteristics of the above alkali metal ion complexes with the receptor R were described by ab initio density functional theory calculations. These calculations have shown that the studied cations bind to the receptor R because they synergistically interact with the polar ethereal fence and with the central benzene ring via cation-π interaction.
authors: Institute of Organic Chemistry and Biochemistry, Academy of Sciences of the Czech Republic, Flemingovo nám. 2, Prague, Czech Republic.
authors: Sille
authors: S
authors: Ehala
authors: Petr
authors: P
authors: Toman
authors: Rajendra
authors: R
authors: Rathore
authors: Emanuel
authors: E
authors: Makrlík
authors: Václav
authors: V
authors: Kašička
mesh_terms: D001555:Benzene Derivatives / Q000737:chemistry*; D002586:Cesium / Q000737:chemistry*; D019075:Electrophoresis, Capillary / Q000379:methods*; D000432:Methanol / Q000737:chemistry; D008958:Models, Molecular; D017711:Nonlinear Dynamics; D012044:Regression Analysis; D012413:Rubidium / Q000737:chemistry*
chemical_list: D001555:Benzene Derivatives; D002586:Cesium; D012413:Rubidium; D000432:Methanol