Spectrophotometric detection of methyl cellulose-manganate(VI) intermediate complex in the oxidation of methyl cellulose by alkaline permanganate

The formation of (methyl cellulose (MC)-(MnO42-)-O-(VI)) MC- + MnO4- <----> (K3) C-2 --> (kb) [MC-(MnO42-)-O-(VI)] where C-2 is a metastable state that interconverts into the [MC-(MnO4-)-O-(VI)] ester intermediate, during the oxidation of methyl cellulose polysaccharide at pH greater than or equal to 12, was followed kinetically by spectrophotometric methods. The reaction was found to be first-order kinetics in [MnO4-] and a fractional order in [MC]. Kinetic and spectrophotometric data confirmed the base-catalysed formation of Mn(VI) inter-mediate complex. A mechanism in agreement with the experimental data was assumed and discussed. (C) 2002 Elsevier Science Ltd. All rights reserved.