Kinetic study by UV Spectrophotometry of Carzol degradation in aqueous medium

Abstract

This paper deals with the kinetic hydrolysis in aqueous media of Carzol or (E) 3-dimethylamino- methyleneaminophenyl-N-methylcarbamate hydrochloride. The Carzol is a bifunctional compound which belongs to the chemical families formamidine and carbamate. This work is carried out by UV Spectrophotometry. The successive determination of 3-aminophenyl-N-methylcarbamate and 3-aminophenol, as the mainproducts of the formamidine and the carbamate groups of Carzol hydrolysis gives evidence for the significant reactivity of this insecticide-acaricide in aqueous media. The obtained negative activation entropy ΔS≠ = - 32.39 J mol-1K-1 indicates a BAC2 mechanism involving bimolecular collapse of the formamidine group of Carzol. While, the obtained positive activation entropy ΔS≠ = +100.24J mol-1 K-1and the absence of basic general catalysis indicate an E1cB mechanism involving unimolecular collapse of the carbamate group of Carzol via a methylisocyanate intermediate.