Reaction of Chromium(III) with 3,4-Dihydroxybenzoic Acid : Kinetics and Mechanism in Weak Acidic Aqueous Solutions
Joint Authors
Zavitsanos, Kimon
Tampouris, Konstantinos
Petrou, Athinoula L.
Source
Bioinorganic Chemistry and Applications
Issue
Vol. 2008, Issue 2008 (31 Dec. 2008), pp.1-8, 8 p.
Publisher
Hindawi Publishing Corporation
Publication Date
2009-02-04
Country of Publication
Egypt
No. of Pages
8
Main Subjects
Abstract EN
The interactions between chromium(III) and 3,4-dihydroxybenzoic acid (3,4-DHBA) were studied resulting in the formation of oxygen-bonded complexes upon substitution of water molecules in the chromium(III) coordination sphere.
The experimental results show that the reaction takes place in at least three stages, involving various intermediates.
The first stage was found to be linearly dependent on ligand concentration k1(obs)_=k0+k1(obs)[3,4-DHBA], and the corresponding activation parameters were calculated as follows: ΔH1(obs)≠=51.2±11.5 kJ mol−1, ΔS1(obs)≠=−97.3±28.9 J mol−1 K−1 (composite activation parameters) .
The second and third stages, which are kinetically indistinguishable, do not depend on the concentrations of ligand and chromium(III), accounting for isomerization and chelation processes, respectively.
The corresponding activation parameters are ΔH2(obs)≠=44.5±5.0 kJ mol−1, ΔS2(obs)≠=−175.8±70.3 J mol−1 K−1.
The observed stages are proposed to proceed via interchange dissociative (Id, first stage) and associative (second and third stages) mechanisms.
The reactions are accompanied by proton release, as is shown by the pH decrease.
American Psychological Association (APA)
Zavitsanos, Kimon& Tampouris, Konstantinos& Petrou, Athinoula L.. 2009. Reaction of Chromium(III) with 3,4-Dihydroxybenzoic Acid : Kinetics and Mechanism in Weak Acidic Aqueous Solutions. Bioinorganic Chemistry and Applications،Vol. 2008, no. 2008, pp.1-8.
https://search.emarefa.net/detail/BIM-454925
Modern Language Association (MLA)
Zavitsanos, Kimon…[et al.]. Reaction of Chromium(III) with 3,4-Dihydroxybenzoic Acid : Kinetics and Mechanism in Weak Acidic Aqueous Solutions. Bioinorganic Chemistry and Applications No. 2008 (2008), pp.1-8.
https://search.emarefa.net/detail/BIM-454925
American Medical Association (AMA)
Zavitsanos, Kimon& Tampouris, Konstantinos& Petrou, Athinoula L.. Reaction of Chromium(III) with 3,4-Dihydroxybenzoic Acid : Kinetics and Mechanism in Weak Acidic Aqueous Solutions. Bioinorganic Chemistry and Applications. 2009. Vol. 2008, no. 2008, pp.1-8.
https://search.emarefa.net/detail/BIM-454925
Data Type
Journal Articles
Language
English
Notes
Includes bibliographical references
Record ID
BIM-454925