Abstract:
The anomalously high reactivity of compounds with one or several lone electron pairs at the atom adjoining the reaction centre (the α-effect) is discussed in relation to reactions involving nucleophilic substitution at the carbon atom in various valence states. The manifestation of the α-effect is noted for nucleophilic addition to a carbon atom; other examples of the α-effect in the chemistry of organic compounds are quoted. The possible causes of the effect are discussed, and a quantitative estimate of the latter is made. The bibliography includes 234 references.