Using microelectrode square-wave voltammetry to monitor the progress of complex homogeneous chemical reactions

A method to monitor the progress of homogeneous chemical reactions using square-wave voltammetry is presented. The square wave voltammogram of a single species may be approximated to a high degree of accuracy with a Gaussian peak. Overlapping voltammograms may be deconvoluted to yield the contribution of individual components to a composite signal. Square-wave voltammograms of reacting mixtures obtained at regular time intervals may thus be resolved to yield reaction profiles showing the loss of reactant and the formation of the product and intermediates. The approach is illustrated by the reaction of 2,4-dinitrochlorobenzcne with fluoride ion in dime thylformamide containing tetrabutylammonium salts. Additionally, the utility of microclectrodes for obtaining simple quantifiable voltammetric responses from compounds whose macroclectrode responses are complicated by chemical followup steps is demonstrated.