title: Effect of structural modifications of diaza-18-crown-6 on the extractability and selectivity of univalent metal picrates.
abstract: The solvent extraction of univalent metal cations with N,N'-dibenzyl-1,4,10,13-tetraoxa-7,16 diaza-2,3,11,12-dibenzocycloocta deca-2,11-diene (L(1)), N,N' didodecyl-1,4,10,13-tetraoxa-7,16-diaza-2,3-benzocylooctadeca-2 ene (L(2)) and N,N'-dibenzyl-1,4,10,13-tetraoxa-7,16 diaza-2,3,11,12-dibenzocyclo octadeca-2,11-diene (L(3)) with picrate anion into dichloromethane has been studied at 25 degrees C by UV-visible spectroscopy. The extractability and selectivity of univalent metal picrates (Li(+), Na(+), Ag(+), PhCH(2)NH(3)(+), NH(4)(+)) was evaluated as a function of [ligand]/[metal cation]. L(2) showed the highest extractability and selectivity for Li(+) over the larger studied cations, and also exhibited the highest [Li(+)]/[NH(4)(+)] selectivity as L/M=1.
authors.affiliation: Department of Analytical Chemistry, Faculty of Science, University of Dicle, Diyarbakir, Turkey.
authors.forename: B
authors.initials: B
authors.lastname: Ziyadanoğullari
authors.forename: G
authors.initials: G
authors.lastname: Topal
authors.forename: S
authors.initials: S
authors.lastname: Erdoğan
authors.forename: C
authors.initials: C
authors.lastname: Hamamci
authors.forename: H
authors.initials: H
authors.lastname: Hoşgoren