Kinetics of reaction of <i>para</i>-substituted β-nitrostyrenes and β -methyl- β-nitrostyrenes with <i>n</i>-butylamine

Abstract

The kinetics of addition of n-butylamine to β nitrostyrene and β -methyl- β-nitrostyrene and their <i>para-</i> substitutedderivatives in acetonitrile at four different temperatures have been followed spectrophotometrically. The order in [substrate] is unity and in [<i>n</i>-butylarnine] it is non-integral. On the basis of the observed kinetic data, a stepwise mechanism involving the formation of zwitterionic addition complex in an equilibrium step followed by conversion into the reaction product via proton transfer in catalytic route by the amine has been proposed. The study of effect of substituents in these reactions shows that the electron-withdrawing substituents accelerate the reaction and electron releasing substituents retard it. Good Hammett correlations have been observed in both the reaction series.