necessarily originate from a cationic species are the most abundant ones. It is suggested that these reactions could proceed through ion-pair intermediates, which are nucleophilically solvated by phelyl or by the solvent. A parallel between phenyl assistance and ‘SN2 (intermediate)’ mechanism, suggested by Bentely & Schleyer, is drawn.
比较了两个环烷基系统的β-甲基和β-苯基衍
生物在M e OH和t- BuOh中的溶剂分解速率常数。看来β-苯基衍
生物以与β-甲基衍
生物相同的速率溶解。缺乏减速归因于苯的协助。通过对反应产物的构型分析确定,那些必然源自阳离子物种的产物是最丰富的那些。建议这些反应可以通过离子对中间体进行,该离子对中间体被苯基或溶剂亲核溶剂化。Bentely&Schleyer建议在苯助剂和“ S N 2(中间体)”机理之间建立一个平行关系。