Nucleophilic reactions in ethylenic derivatives. Part XII. Reactions of β-fluoro-4-nitrostyrenes with nucleophiles

Abstract

The reactions of cis- and trans-β-fluoro-4-nitrostyrenes with methoxide and benzenethiolate ions have been studied and their rates measured. With both reagents and both substrates direct substitution was observed. In contrast with the behaviour of cis-chloro- and bromo-styrenes, the elimination mechanism is not operative. The substitution reaction does not occur with retention of configuration, as found for the previously studied halogenoethylenes. In each case the more thermodynamically stable derivative was formed.

The implications of these new findings for the mechanism of the reactions of vinyl halides with nucleophiles are discussed.