Characterization and Reactions of Copper (II) - Glycerol Complex

In solution, either aqueous or methanolic, the colour of copper(II)-glycerol complex (Cu-Gly) is deep midnight blue. Its presence was confirmed by its UV-VIS spectrum, which was a broad unsymmetrical band with a ƛmax ~625 nm. The Na₂SO₄ bisalt of the complex was successfully isolated and. charact...

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Main Author: Abu Hassan, Hazimah
Format: Thesis
Language:English
English
Published: 1998
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Online Access:http://psasir.upm.edu.my/id/eprint/8995/1/FPP_1998_12_A.pdf
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spelling my-upm-ir.89952010-12-28T06:44:36Z Characterization and Reactions of Copper (II) - Glycerol Complex 1998 Abu Hassan, Hazimah In solution, either aqueous or methanolic, the colour of copper(II)-glycerol complex (Cu-Gly) is deep midnight blue. Its presence was confirmed by its UV-VIS spectrum, which was a broad unsymmetrical band with a ƛmax ~625 nm. The Na₂SO₄ bisalt of the complex was successfully isolated and. characterized. The detailed characterization studies revealed interesting behaviours of the complex and its unique chemistry. The coordination of glycerol to Cu(IT) was evidenced by the absorption frequencies in the region 1500-1200 cm⁻¹ of the IR spectrum of the complex. The CHN analysis of the complex led to a proposed molecular formula of The uv-visible spectra showed absorption maxima at 381 nm and 625 nm with a shoulder at 531nm. The calculated 10Dq for the complex fell in the range of strong ligands. The structure of Cu-Gly complex ion was therefore suggested to be atetragonally distorted octahedron, with the two glycerolate ions lying in a square plane. The two water molecules were assumed to be weakly bonded at the axial positions. The study also indicated that coordination of glycerol to Cu(IT) was via its 1 ,2-hydroxyl positions. Oxidations of Cu-Gly complex were carried out in-situ, either in aqueous or methanolic media, using the following oxidants: HN03, Br2, Cr03, pyridiniumchlorochromate (PCC), H202, KMn04 and K2Cr207. Four of these gave oxidative products such as CO2, formic acid, oxalic acid and glyceric acid. These products were identified spectroscopically and confirmed by simple chemical tests, where necessary. To further understand the chemistry of Cu-Gly complex, the oxidations were also carried out on its insoluble intermediate and pure glycerol (uncomplexed). The results from this study, supported further by the identified products and the proposed mechanisms for the reactions, have shown that the coordination of Cu(II) was indeed at the l ,2-position of glycerol. The relative activities of the oxidants are parallel to the EO of their half reactions. Therefore a general trend in predicting the products (cleavage or noncleavage) can be postulated. The results of the study also show that Cu(IT) does play a major role in the reactions of Cu-Gly complex especially those involving electron transfer. The GC technique developed in this study is shown to be simple, reliable,practical and, hence, suitable for direct analyses of glycerol and its derivatives. No derivatization was required. Glycerin Chemical tests and reagents 1998 Thesis http://psasir.upm.edu.my/id/eprint/8995/ http://psasir.upm.edu.my/id/eprint/8995/1/FPP_1998_12_A.pdf application/pdf en public phd doctoral Universiti Putra Malaysia Glycerin Chemical tests and reagents Faculty of Educational Studies English
institution Universiti Putra Malaysia
collection PSAS Institutional Repository
language English
English
topic Glycerin
Chemical tests and reagents

spellingShingle Glycerin
Chemical tests and reagents

Abu Hassan, Hazimah
Characterization and Reactions of Copper (II) - Glycerol Complex
description In solution, either aqueous or methanolic, the colour of copper(II)-glycerol complex (Cu-Gly) is deep midnight blue. Its presence was confirmed by its UV-VIS spectrum, which was a broad unsymmetrical band with a ƛmax ~625 nm. The Na₂SO₄ bisalt of the complex was successfully isolated and. characterized. The detailed characterization studies revealed interesting behaviours of the complex and its unique chemistry. The coordination of glycerol to Cu(IT) was evidenced by the absorption frequencies in the region 1500-1200 cm⁻¹ of the IR spectrum of the complex. The CHN analysis of the complex led to a proposed molecular formula of The uv-visible spectra showed absorption maxima at 381 nm and 625 nm with a shoulder at 531nm. The calculated 10Dq for the complex fell in the range of strong ligands. The structure of Cu-Gly complex ion was therefore suggested to be atetragonally distorted octahedron, with the two glycerolate ions lying in a square plane. The two water molecules were assumed to be weakly bonded at the axial positions. The study also indicated that coordination of glycerol to Cu(IT) was via its 1 ,2-hydroxyl positions. Oxidations of Cu-Gly complex were carried out in-situ, either in aqueous or methanolic media, using the following oxidants: HN03, Br2, Cr03, pyridiniumchlorochromate (PCC), H202, KMn04 and K2Cr207. Four of these gave oxidative products such as CO2, formic acid, oxalic acid and glyceric acid. These products were identified spectroscopically and confirmed by simple chemical tests, where necessary. To further understand the chemistry of Cu-Gly complex, the oxidations were also carried out on its insoluble intermediate and pure glycerol (uncomplexed). The results from this study, supported further by the identified products and the proposed mechanisms for the reactions, have shown that the coordination of Cu(II) was indeed at the l ,2-position of glycerol. The relative activities of the oxidants are parallel to the EO of their half reactions. Therefore a general trend in predicting the products (cleavage or noncleavage) can be postulated. The results of the study also show that Cu(IT) does play a major role in the reactions of Cu-Gly complex especially those involving electron transfer. The GC technique developed in this study is shown to be simple, reliable,practical and, hence, suitable for direct analyses of glycerol and its derivatives. No derivatization was required.
format Thesis
qualification_name Doctor of Philosophy (PhD.)
qualification_level Doctorate
author Abu Hassan, Hazimah
author_facet Abu Hassan, Hazimah
author_sort Abu Hassan, Hazimah
title Characterization and Reactions of Copper (II) - Glycerol Complex
title_short Characterization and Reactions of Copper (II) - Glycerol Complex
title_full Characterization and Reactions of Copper (II) - Glycerol Complex
title_fullStr Characterization and Reactions of Copper (II) - Glycerol Complex
title_full_unstemmed Characterization and Reactions of Copper (II) - Glycerol Complex
title_sort characterization and reactions of copper (ii) - glycerol complex
granting_institution Universiti Putra Malaysia
granting_department Faculty of Educational Studies
publishDate 1998
url http://psasir.upm.edu.my/id/eprint/8995/1/FPP_1998_12_A.pdf
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