Metal-Ion Catalysis in Alkaline Ethanolysis of 2-Pyridyl Thionobenzoate: Effects of Modification of Electrophilic Center from C=O to C=S
作者:Ik-Hwan Um、Yoon-Ju Song、Min-Young Kim、Jae-In Lee
DOI:10.5012/bkcs.2013.34.5.1525
日期:2013.5.20
second-order rate constants for the reactions with the dissociated and ion-paired EtOM, respectively) has revealed that the ion-paired EtOM is more reactive than the dissociated , and ions catalyze the reactions in the order . The plot of log vs. results in an excellent linear correlation, indicating that the reactions are catalyzed by the solvated ions but not by the bare ions. The reactions of 5b with
已通过分光光度法测量了 2-吡啶基硫代苯甲酸酯 (5b) 与碱金属乙醇盐 (EtOM, , , 和 18-crown-6-ether complexed) 在无水乙醇中的亲核取代反应的伪一级速率常数 ()在 。无论离子的性质如何,vs. 的曲线都向上弯曲,而 vs. 的曲线是具有正截距的线性曲线。分解成 和 (即,分别与解离和离子对 EtOM 反应的二级速率常数)表明,离子对 EtOM 比解离 EtOM 更具反应性,并且离子按顺序催化反应. 对数与曲线的关系得到极好的线性相关性,表明反应是由溶剂化离子催化的,而不是由裸离子催化的。