Abstract
The kinetics of phenylmethanesulfonyl chloride in methanol-water, ethanol-water, acetone-water and acetonitrile-water has been investigated. The rate was faster in protic solvents than in aprotic solvents while susceptibility of rate to the ionizing power, i. e., m of the Winstein plot and solvation number of the transition state were much smaller in protic solvents. This was considered in the light of initial state stabilization by hydrogen-bonding solvation of the protic solvents. It was concluded that the reaction proceeds by an $S_N2$ mechanism in which bond-formation precedes bond-breaking at the transition state in all solvent systems.
메탄올-물, 에탄올-물, 아세톤-물 및 아세토니트릴-물의 二成分 混合溶媒에서 鹽化페닐메탄술포닐의 加溶媒分解反應을 速度論的으로硏究하였다. 反應速度는 反陽性子溶媒에서 보다 陽性子溶媒에서 더 빨랐으며, 이온化能力에 對한 反應速度의 感度 즉 Winstein 圖示의 m와 轉移狀態의 溶媒和數는 陽性子溶媒에서 훨씬 작았다. 이것은 陽性子溶媒의 水素結合溶媒和에 依한 初期狀態의 安定化로서 생각할 수 있다. 反應은 모든 溶媒系에 있어서 轉移狀態의 結合形成이 結合破壤을 앞지르는$S_N2$ 메카니즘으로 일어난다 할 수 있다.