A study of the rates of hydrolysis of 3-Me-2-butyl bromide and methanesulfonate in water leads to values of ΔCp≠ of −80 and −40 cal deg−1 mole−1, respectively. The product was about 85–95 % t-pentanol, the remainder being olefin. The value of ΔCp≠ for the solvolysis of the methanesulfonate in D2O was −44 cal deg−1 mole−1. The kinetic solvent isotope effect (k.s.i.e.) for the latter was unusually low (k.s.i.e. = 1.047 at 5 °C and 1.025 at 25 °C). Deuteration at C-3 led to a reduction in the rate of hydrolysis by a factor of about 2.25. This is consistent with an activation process involving "hydrogen participation" as previously reported by Winstein and Takahashi for solvolysis of the corresponding tosylate in acetic acid. In contrast to the latter work, the reaction in water appears to be uncomplicated.
一项关于3-Me-2-butyl溴化物和甲烷磺酸盐在水中水解速率的研究表明,它们的ΔCp≠值分别为-80和-40 cal deg^-1 mole^-1。产物约为85-95%的t-戊醇,其余为烯烃。在D2O中,甲烷磺酸盐的溶剂解值ΔCp≠为-44 cal deg^-1 mole^-1。后者的动力学溶剂同位素效应(k.s.i.e.)异常地低(k.s.i.e.=1.047(5℃)和1.025(25℃))。在C-3处的氘代导致水解速率降低约2.25倍。这与Winstein和Takahashi之前在乙酸中对应对磺酸酯的溶剂解作用所报道的“氢参与”激活过程一致。与后者的研究相比,水中的反应似乎不那么复杂。