Influence of Pressure on the Menschutkin-Type Reaction of Phenethyl Arenesulfonates with Pyridine

Article abstract of DOI:10.1246/bcsj.60.1149

Kinetic investigation of β-phenethyl arenesulfonates with pyridine in acetonitrile revealed that the rates of these reactions which were lower than those of the reaction of benzyl benzenesulfonate with pyridine in acetone were increased with raising temperatures and pressures.The activation volumes were comparable to those of benzyl system, but the activation entropies were negatively larger than those of benzyl system.From these phenomena it can be deduced that phenethyl system has more S_N2 character in the transition state, comparing with the reaction of benzyl system.With raising pressures the Hammett reaction parameters (ρ) were decreased, indicating that the reaction is probably closer to the tihgt S_N2 character at higher pressures.