Cross‐interaction constants as a measure of the transition state structure. Part 8. Mechanism of the reaction of 2‐phenylethyl benzenesulphonates with benzylamine in acetonitrile

The kinetics of reactions between 2‐phenylethyl benzenesulphonates (2‐PEB) and benzylamines in acetonitrile at 65·0°C have been studied; the mechanism was examined on the basis of the sign and magnitude of cross‐interaction constants ρij and βij. In contrast to the reactions of 2‐PEB with anilines in methanol, participation of the aryl‐assisted pathway was negligible, with a strong indication that the reaction proceeds largely by an intermolecular SNi mechanism with a four‐centre transition state (TS). The effect of substituents on the TS variation was in accord with the predictions of the quantum mechanical model.