Stoichiometric solvation effects. Solvolysis of methanesulfonyl chloride

Solvolyses of methanesulfonyl chloride in water, D2O, CH3OD, and in aqueous binary mixtures of acetone, ethanol and methanol are investigated at 25, 3 5 and 45 degreesC. The Grunwald-Winstein plot of first-order rate constants for the solvolytic reaction of methanesulfonyl chloride with Y-Cl(based on 2-adamantyl chloride) shows marked dispersions into three separate lines f or three aqueous mixtures with a small In value (m < 0.30), and shows a rat e maximum for aqueous alcoholic solvents. Stoichiometric third-order rate c onstants, k(ww) and k(aa) were calculated from the observed first-order rat e constants and (k(aw) + k(wa)) was calculated from the k(ww) and k(aa) val ues. The kinetic solvent isotope effects determined in water and methanol a re consistent with the proposed mechanism of the general base catalyzed and /or SAN/S(N)2 reaction mechanism for methanesulfonyl chloride solvolyses ba sed on mass law and stoichiometric solvation effect studies.