Nucleophilic Addition of Amino-groups to an Activated Carbon–Carbon Double Bond

The review presents data on the effect of structural and steric factors, catalysts, and solvents on the mode and rate of condensation of activated olefins with amines, which indicate that the mechanisms of such condensations are to some extent general. The considerable importance of the steric inhibition of the reactions is evidence in favour of the hypothesis of a polar transition state characterised by a rigid structure. Proton transfer involving a proton donor and (or) acceptor or, more rarely, the ejection of a negative ion (see the reactions of β-halogeno-olefins) plays a significant role in the stabilisation of the transition state. The sequence of relative activities of the olefins CH₂=CHX is affected both by the polarising effect of the group X and the possibility of the delocalisation of the charges in the activated complex. Nevertheless the problems of the catalytic effect of proton-donating, alkaline, and particularly peroxidic additives are still not completely clear and require further study. The bibliography includes 266 references.