02417nas a2200241   4500008004100000022001400041245013200055210006900187260000800256300001200264490000700276520156800283653002301851653002801874653002001902653001601922653002201938653002201960100002601982700002002008700002302028856012402051       2021                        eng d  a0538-806600aEstimation of reaction kinetics for aromatic and heterocycles nitration in mixed acids through computational chemistry approach0 aEstimation of reaction kinetics for aromatic and heterocycles ni  cMAR  a319-3320 v533 a<p>Nitration of aromatic compounds and heterocycles in mixed acid environment is one of the regularly performed large-scale reactions in the chemical industry. Although the reaction mechanism of nitration of aromatics in mixed acid is well established, the development of a methodology for the evaluation of kinetics of exothermic aromatic nitrations in a simplified and accurate way is necessary. Here we evaluate the applicability of a kinetic evaluation methodology based on Hammett's acidity function, acidity function, and empirical activity coefficient for the nitration reaction. The contributions from the functional groups on the aromatic ring and quantitative structure-activity relationships technique are considered for these evaluations. Natural bond orbital and magnetic index nucleus independent chemical shift analyses were carried out to obtain the substitution constants. The rate constant and activation energy values were evaluated at various temperatures and sulfuric acid strengths. The results were validated by comparing with the experimental data from the literature for several molecules. The effect of various functional groups (viz carbonyl, carboxyl, methyl, and amine) substituted on the benzene ring was also evaluated. For a few identified substrates, the data were used for estimation of residence time needed for complete conversion in continuous stirred tank reactor and in a plug flow reactor to quantify the effect of substitution constant and strength of sulfuric acid. The approach will help select a suitable reactor.</p>
10aAromatic nitration10acomputational chemistry10aHammett analogy10amixed acids10aReaction kinetics10areactor selection1 aJadhav, Pandurang, M.1 aPandey, Raj, K.1 aKulkarni, Amol, A.  uhttps://library.ncl.res.in/content/estimation-reaction-kinetics-aromatic-and-heterocycles-nitration-mixed-acids-through