Kinetics of the formation of the 1,3-complex and on the formation and decomposition of the intermediate complex. Reaction of 2,4,6-trinitroanisole with n-butylamine in dimethyl sulphoxide

Abstract

The reaction of 2,4,6-trinitroanisole with n-butylamine in dimethyl sulphoxide occurs in three stages, which are observed separately by stopped-flow spectrophotometry. Stages I and II are the formation of the kinetically controlled 1,3-complex and the thermodynamically stable intermediate complex, respectively. Stage Ill is the decomposition of the intermediate. The mechanism of the formation and decomposition of the intermediate is indicated to be rapid equilibrium deprotonation of the zwitterionic complex followed by rate-limiting, general acid-catalysed leaving-group departure. The product is finally in equilibrium with both its conjugate base and its 1,3-complex from attack of n-butylamine.