In the present study, Polymer supported metal complexes were synthesized by chelating chitosan with Cu(Ⅱ) and Fe(Ⅲ) ions and were investigated as catalysts for the oxidation of L-ascorbic acid The results obtained from this study can be summarized as follows: 1) The chitosan-Cu(Ⅱ) and -Fe(Ⅲ) complex catalysts exhibited relatively high catalytic effect and good catalyst recovery when compared to the cases of free Cu(Ⅱ) and Fe(Ⅲ) ions In tile oxidation of L-ascorbic acid and the kinetic behavior followed enzymatic kinetics of Michaelis-Menten type. 2) The chitosan-Cu(Ⅱ) complex catalytic showed higher catalytic activity than the chitosan-Fe(Ⅲ) system. 3) The catalytic reaction rate constants (kcat) of this oxidation at 25℃ were estimated to be 1.19 min^-1 and 0.10 min^-1 for the chitosan-Cu(Ⅱ) and -Fe(Ⅲ) catalyst systems, respectively. 4) The calculated parameters at 25℃ obtained with the Arrhenius and Eyring rate expressions for the chitosan-Cu(Ⅱ) and -Fe(Ⅲ) catalytic systems were as follows: Ea, 4.32 and 5.28 Kcal/mole; ΔG^*, 7.34 and 18.81kca1/mo1c; ΔH^*, 3.73 and 4.69 Kcal/mole; ΔS^*, -0.046 and -0.047 cal/mole℃, respectively.

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