N,N-dimethylformamide (DMF), and N,N-dimethylacetamide (DMA) reactions with NO3, OH and Cl: A theoretical study of the kinetics and mechanisms

Abstract

A theoretical study of the kinetics and the mechanism of the hydrogen abstraction by OH, Cl and NO3 radicals from two amides (DMF and DMA) has been investigated. Calculations were carried out using DFT B3LYP/6-311++G(2d,pd)/CBS-QB3 and transition-state theory. This work provides the first theoretical determination of the rate coefficients and detailed mechanism for the reactions of OH, NO3 radicals and chlorine atoms with DMF/DMA, over a temperature range 273–380 K and at atmospheric pressure. The obtained rate coefficients are in reasonable agreement with experiments. Results indicate that the mechanism of the Cl and NO3 reactions with amides goes preferentially through H-abstraction from (C(O)H) and (C(O)CH3) groups. Meanwhile the mechanism of the OH with amides (DMF, DMA) is dominated by H-abstraction from the N-methyl groups. Keywords: Amide, CBS-QB3, Kinetics, Mechanism, OH radical, Nitrate radical, Chlorine atom, Rate constant