Abstract
The electrochemical oxidation of two flavonoids, quercetin and catechin, has been studied in the absence and presence of nitrite ion. A reaction mechanism has been proposed, based on cyclic voltammetry. Variation in the cathodic peak, due to the competition between the intramolecular Michael addition of hydroxy group and the intermolecular addition of nitrite ion, was studied as a critical parameter. The results indicate an EC mechanism for both electrode reactions. The observed homogeneous rate constant (kobs) for the Michael addition was estimated by comparing the experimental cyclic voltammetric responses with the digital simulated results.
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