Kinetic studies of the reaction of 1-dialkylamino-2,4-dinitronaphthalenes with butylamine in dimethyl sulfoxide

Abstract

The nucleophilic substitution reaction of butylamine with 1-pyrrolidino-2,4-dinitronaphthalene (1a) in dimethyl sulfoxide is subject to general base catalysis, whereas the reaction of the same amine with 1-piperidino-(1b) or 1-dimethylamino-2,4-dinitronaphthalene (1c) is not. General base catalysis is shown to be a consequence of rate-limiting deprotonation of the zwitterionic intermediate complex. The structures of 1a and 1b analysed by X-ray crystallography fairly tie in with the great difference in behaviour between 1a and 1b.