Solvent Effects and Steric Course in the Solvolysis of 1,3,3-Trimethyl-2-oxocyclopentyl Mesylate in Comparison with 1,1,3,3-Tetramethyl-2-oxobutyl System
作者:Ken’ichi Takeuchi、Takuhiro Ushino、Takao Okazaki、Toshikazu Kitagawa、Tomomi Kinoshita、Yasushi Ohga、Koichi Tanaka、Fumio Toda
DOI:10.1246/bcsj.74.363
日期:2001.2
The rates of solvolysis in various solvents were determined for 1,1,3,3-tetramethyl-2-oxobutyl tosylate (1OTs) and 1,3,3-trimethyl-2-oxocyclopentyl mesylate (4OMs). The rate data for 1OTs reinforced that the linear Grunwald-Winstein (GW) relationship of 1OMs previously reported by Creary for non-aqueous solvents must also hold for aqueous organic solvents. 4OMs showed a markedly dispersed GW relationship
测定了 1,1,3,3-四甲基-2-氧代丁基甲苯磺酸酯 (1OT) 和 1,3,3-三甲基-2-氧代环戊基甲磺酸酯 (4OM) 在各种溶剂中的溶剂分解速率。1OT 的速率数据强化了 Creary 先前报告的 1OM 的线性 Grunwald-Winstein (GW) 关系对于非水性溶剂也必须适用于水性有机溶剂。4OM 显示出明显分散的 GW 关系,另一方面,与涉及亲核参数的扩展 GW 方程密切相关。这种溶剂依赖性、添加叠氮化钠对速率的显着影响以及溶剂分解产物构型的 100% 反转表明 4OM 的溶剂分解将归类为 SN2(中间),而 1OM 和 1OT 通过限制 SN1 进行溶剂分解。