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Copper complexes immobilized to chitosan.

E Chiessi·G Paradossi·M Venanzi·B Pispisa
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Abstract

Polymeric ligands, such as 2-substituted pentanedioic acid (2), 2-substituted propanoic acid (3), and deoxylactit-1-yl (4) derivatives of chitosan (1), were used to prepare copper complexes that are widely soluble in aqueous solution. EPR results (100 K) show that all association complexes basically have a tetragonal symmetry. Visible CD spectra suggest, however, that the order of increasing departure from this geometry is Cu-(1) approximately Cu-(3) less than Cu-(2) less than or equal to Cu-(4), the lack of sterically constraining side-chains in (1) and (3) allowing a more symmetric arrangement of ligands around the central metal ion. Results on the catalytic activity of the association complexes for air oxidation of catechol derivatives are also presented.

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CatalysisChelating AgentsChitinChitosanCircular DichroismCopperElectron Spin Resonance SpectroscopyEpinephrineMolecular StructureOxidation-ReductionSolubilitySolutionsJournal ArticleResearch Support, Non-U.S. Gov't

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E Chiessi, G Paradossi, M Venanzi, B Pispisa. 1992-05-01. Copper complexes immobilized to chitosan.. https://doi.org/10.1016/0162-0134(92)80014-m

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