Nucleophilic attacks on carbon–carbon double bonds. Part XXIII. Substitution of β-chloro-α-phenylacrylonitriles

Abstract

Substitutions of (E)- and (Z)-β-chloro-α-phenylacrylonitriles by arenethiolate, azide, and ethoxide ions proceed with retention of configuration, while reactions with piperidine or morpholine give the same enamino-nitrile from the two isomeric chlorides. The second-order rate constants give the nucleophilicity order ArS^– > EtO^– > piperidine > PhO^– > morpholine > N₃^–. These results are discussed in terms of the addition–elimination route of nucleophilic vinylic substitution, and the data are compared with those found for related reactions.