Nucleophilic displacement in polyhalogenoaromatic compounds. Part 1. Kinetics of reaction of polychlorofluorobenzene derivatives

Abstract

The rate; of displacement of fluorine from some polychloropolyfluorobenzene derivatives by sodium methoxide in methanol have been studied. The second-order rate constants show a dependence upon halogen substituent effects similar to that found in aromatic nucleophilic displacement reactions with other activating groups. The mechanisms by which halogen substituents activate benzene systems to such attack are discussed: only two, classical electronic interactions are needed. A simple numerical method is described which enables the prediction of rates and orientations of displacement, and of 19F n.m.r. shifts, in polyhalogenobenzene derivatives.