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Copper complexes immobilized to chitosan

1992; Elsevier BV; Volume: 46; Issue: 2 Linguagem: Inglês

10.1016/0162-0134(92)80014-m

1873-3344

Ester Chiessi, Gaio Paradossi, Mariano Venanzi, B. Pispisa,

Analytical Chemistry and Sensors

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) ≈ Cu-(3) < Cu-(2) ≦ 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.