Analyse conformationnelle a l'aide de la notation des angles de torsion-VIII: Interpretation conformationnelle de la reaction de substitution nucleophile(SN2) dans la serie des cycles petits et moyens

Taking geometric constraints into account, involved at the carbon atom undergoing configurational inversion in S_N2 displacement reactions of cyclic compounds, the conformational course of the reaction can be analysed. This method allows a rationalization of the relative rates of S_N2 reactions of isomeric compounds in the cyclohexane, cyclohexene, cyclopentane, and cyclopentene series. Conformational factors involved in the displacement reaction, which may orient it towards either S_N2 or S_N2' type of reaction are discussed.