title: Recognition of silver cations by a cucurbit[8]uril-induced supramolecular crown ether.
abstract: The host-guest interaction of cucurbit[8]uril (Q[8]) with a synthesized guest molecule, consisting of naphthalene and viologen moieties bridged by a carbon oxygen chain, was investigated by (1)H NMR and UV-Vis spectroscopy. The results indicated the formation of an inclusion complex in a ratio of 1 : 1 with a moderate association constant of Ka = (1.1 ± 0.2) × 10(6) L mol(-1). The formation of this special complex is driven by the markedly enhanced charge-transfer interaction between the electron-rich and electron-deficient guest molecule inside the hydrophobic cavity of Q[8], while the carbon oxygen chain stays outside of Q[8] to form a supramolecular crown ether. Screening of the metal cation substrate suggested that the inclusion complex recognizes Ag(+) ions with high selectivity, as shown by UV-Vis spectroscopy.
authors.affiliation: Key Laboratory of Macrocyclic and Supramolecular Chemistry of Guizhou Province, Guizhou University, Guiyang 550025, P.R. China. ecnuc@163.com.
authors.forename: Qing-Xia
authors.initials: QX
authors.lastname: Geng
authors.affiliation: Key Laboratory of Macrocyclic and Supramolecular Chemistry of Guizhou Province, Guizhou University, Guiyang 550025, P.R. China. ecnuc@163.com.
authors.forename: Fang
authors.initials: F
authors.lastname: Wang
authors.affiliation: Key Laboratory of Macrocyclic and Supramolecular Chemistry of Guizhou Province, Guizhou University, Guiyang 550025, P.R. China. ecnuc@163.com.
authors.forename: Hang
authors.initials: H
authors.lastname: Cong
authors.affiliation: Key Laboratory of Macrocyclic and Supramolecular Chemistry of Guizhou Province, Guizhou University, Guiyang 550025, P.R. China. ecnuc@163.com.
authors.forename: Zhu
authors.initials: Z
authors.lastname: Tao
authors.affiliation: CSIRO Manufacturing Flagship, P.O. Box 218, Lindfield, NSW 2070, Australia. gang.wei@csiro.au.
authors.forename: Gang
authors.initials: G
authors.lastname: Wei