title: Liquid-liquid extraction and liquid chromatographic studies on interactions of inorganic anions with coordinatively unsaturated copper(II) complexes of heterocyclic azo compounds.
abstract: The interactions between Cu(II) complexes with heterocyclic azo compounds and several anions were studied by equilibrium analysis of ion-pair extraction, RP-HPLC of metal complexes, and ion chromatography of anions on an ODS column coated with Cu(II) complexes of the long alkyl derivatives. Both ion-pair extraction and HPLC studies demonstrated that a dicationic complex with 8-(3,5-dibromo-2-pyridylazo)-5-aminoquinoline interacted with anions stronger than a monocationic complex with 2-(2-pyridylazo)methylphenol. Anions were more retained on the column coated with dicationic Cu(II) complex. Such differences were quantitatively ascribed to the first ion-pair formation of the dicationic complex giving a monocationic species.
authors.affiliation: Graduate School of Engineering, Nagoya Institute of Technology, Gokiso, Showa, Nagoya 466-8555, Japan. yasui.takashi@nitech.ac.jp
authors.forename: Takashi
authors.initials: T
authors.lastname: Yasui
authors.forename: Yuki
authors.initials: Y
authors.lastname: Kashihara
authors.forename: Fumiko
authors.initials: F
authors.lastname: Miyake
authors.forename: Seiko
authors.initials: S
authors.lastname: Sugitani
authors.forename: Hiromichi
authors.initials: H
authors.lastname: Yamada
authors.forename: Akio
authors.initials: A
authors.lastname: Yuchi