Rate and Product Studies in the Solvolyses of Two Arenesulfonic Anhydrides
The specific rates of solvolysis of benzenesulfonic anhydride (1) and p-toluenesulfonic anhydride (2) have been measured conductometrically at −10°C in 34 solvents for 1 and 33 solvents for 2. Studies at higher temperatures have allowed extrapolated values in additional solvents to be calculated. All of the values, for 35 solvents for 1 and for 37 solvents for 2, have been used in an extended Grunwald–Winstein equation treatment using NT and YOTs values. Activation parameters in several solvents and kinetic solvent isotope effects (MeOH/MeOD) have been determined for both substrates. Product selectivity values ( S) have been determined for binary mixtures of water with ethanol, methanol, or 2, 2, 2-trifluoroethanol. The results from the kinetic and product studies are compared to those previously reported for methanesulfonic anhydride (3). An SN2 mechanism is proposed for the solvolytic displacement reactions of the three substrates in all of the solvents used in the investigation.