Please use this identifier to cite or link to this item:
https://hdl.handle.net/2440/44196
Citations | ||
Scopus | Web of Science® | Altmetric |
---|---|---|
?
|
?
|
Type: | Journal article |
Title: | UV-Vis and fluorimetric Al³⁺, Zn²⁺, Cd²⁺ and Pb²⁺ complexation studies of two 3-hydroxyflavones and a 3-hydroxythioflavone |
Other Titles: | UV-Vis and fluorimetric Al(3+), Zn(2+), Cd(2+) and Pb(2+) complexation studies of two 3-hydroxyflavones and a 3-hydroxythioflavone |
Author: | Valente, J. Buntine, M. Lincoln, S. Ward, A. |
Citation: | Inorganica Chimica Acta, 2007; 360(10):3380-3386 |
Publisher: | Elsevier Science SA |
Issue Date: | 2007 |
ISSN: | 0020-1693 1873-3255 |
Statement of Responsibility: | John V. Valente, Mark A. Buntine, Stephen F.Lincoln and A. David Ward |
Abstract: | The complexation of Al³⁺, Zn²⁺, Cd²⁺ and Pb²⁺ by the 3-hydroxyflavones: 3-hydroxy-2-(2-methoxyphenyl)-4H-1-benzopyran-4-one (H1) and 3-hydroxy-2-(4-methoxyphenyl)-4H-1-benzopyran-4-one (H2), and by the 3-methoxythioflavone: 3-hydroxy-2-(2-methoxyphenyl)- 4H-1-benzopyran-4-thione (H3) have been studied spectrophotometrically and fluorimetrically to determine the corresponding complexation constants, Ksp and Kfl, in 5:95 water:ethanol (v/v) solution for which [HClO4] was either 10⁻² or 10⁻⁵ mol dm⁻³ and I = 0.10 mol dm⁻³ (NaClO₄) at 298.2 K. Complexation occurs dominantly through the deprotonated ligand for [Al(1)]²⁺ and [Al(2)]²⁺ for which logKsp = 4.51 and 4.73, respectively, in 10⁻² mol dm⁻³ HClO₄ and 4.21 and 4.61 in 10⁻⁵ mol dm⁻³ HClO₄. For Pb²⁺ complexation by H1, H2 and H3 is characterized by logKsp = 2.20, 2.57 and 3.22, respectively, in 10⁻² mol dm⁻³ HClO₄ and 4.70, 5.38 and 5.74 in 10⁻⁵ mol dm⁻³ HClO₄. Equilibrium mixtures of [Pb(H1)]²⁺ and [Pb1]⁺, [Pb(H2)]²⁺ and [Pb2]⁺, and [Pb(H3)]²⁺ and [Pb3]⁺ appear to be formed. Complexation of Zn²⁺ and Cd²⁺ by all three ligands was only detected in 10⁻⁵ mol dm⁻³ HClO₄. For Zn²⁺ complexation by H1, H2 and H3 logKsp = 3.22, 3.74 and 4.46 and for Cd²⁺ the corresponding values are 2.39, 2.40 and 3.72 for Cd²⁺. Only [Al1] ²⁺ and [Al2] ²⁺ show significant fluorescence and are characterized by logKfl = 6.30 and 7.49 in 10⁻² mol dm⁻³ HClO₄. |
Keywords: | 3-Hydroxyflavones 3-Hydroxythioflavones Metal complexes Stability constants Fluorescence |
Description: | Copyright © 2007 Published by Elsevier B.V. |
DOI: | 10.1016/j.ica.2007.04.011 |
Description (link): | http://www.elsevier.com/wps/find/journaldescription.cws_home/504086/description#description |
Published version: | http://dx.doi.org/10.1016/j.ica.2007.04.011 |
Appears in Collections: | Aurora harvest Chemistry publications Environment Institute publications |
Files in This Item:
There are no files associated with this item.
Items in DSpace are protected by copyright, with all rights reserved, unless otherwise indicated.