Tri(hetero)substituted Carbonium Ions. I. Neighboring-Group Participation of the<i>N</i>,<i>N</i>-Dimethyldithiocarbamate Function Involving the Intermediacy of 2-Dimethylamino-1,3-dithiolanylium Ion
作者:Takeshi Nakai、Yoshio Ueno、Makoto Okawara
DOI:10.1246/bcsj.43.156
日期:1970.1
On the basis of the solvent effect on the product ratio, and kinetic experiments it has been verified that neighboring-group participation of the N,N-dimethyldithiocarbamate function would be involved through the intermediacy of the isolated anchimeric carbonium ion, and that such participation is more predominant in nonpolar aprotic solvents such as dioxane and tetrahydrofuran. The mechanism of the
在各种溶剂中研究了 1,2-二氯乙烷与 N,N-二甲基二硫代氨基甲酸钠的等摩尔反应。作为主要产物,亚乙基双(N,N-二甲基二硫代氨基甲酸酯)和 2-二甲氨基-1,3-二硫基鎓盐(高氯酸盐或四苯基硼酸盐)的产率随所用溶剂而异。根据溶剂对产物比的影响,以及动力学实验,已经证实 N,N-二甲基二硫代氨基甲酸酯官能团的邻基参与将通过分离的嵌合碳正离子的中介参与,并且这种参与是在非极性非质子溶剂(如二恶烷和四氢呋喃)中更为突出。建立了2-二甲氨基-1,3-二硫基鎓离子与二硫代氨基甲酸根阴离子反应的机理。