Reactions of 2-Cyano-2-dimethylamino-1,3-dithiolane
作者:Kazuhisa Hiratani、Takeshi Nakai、Makoto Okawara
DOI:10.1246/bcsj.47.904
日期:1974.4
The reactions of 2-cyano-2-dimethylamino-1,3-dithiolane (2) with electrophiles (organic halides and perchloric acid) and nucleophiles were investigated. It was found that 2 dissociated partially to 2-dimethylamino-1,3-dithiolan-2-ylium (1) and cyanideions in polar solvents. In the reactions of 2 with electrophiles, nitriles were obtained along with the formation of salts of 1. The reactions of 2 with
Tri(hetero)substituted Carbonium Ions. II. 2-Dialkylamino-1,3-dithiolanylium Ions. Reactions with Nucleophiles and Ambident Behaviors
作者:Takeshi Nakai、Makoto Okawara
DOI:10.1246/bcsj.43.1864
日期:1970.6
including oxygen, sulfur and nitrogen nucleophiles have been investigated. Examination of the isolated products reveals that these trihetrosubstituted carbonium ions behave as ambident electrophiles toward nucleophiles with two reactive sites, i.e., the electron-deficient centered carbon (a) and the ring-methylene carbon atom (b), and that the nature of nucleophiles greatly affects the reaction course
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-groupparticipation 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
Tri(hetero) substituted Carbonium Ions. VI. An Anomalous Reaction of 2-Methylthio-1,3-dithiolanylium Ion with<i>N</i>,<i>N</i>-Dimethyldithiocarbamate Anion
作者:Takeshi Nakai、Makoto Okawara
DOI:10.1246/bcsj.43.3882
日期:1970.12
not be ascribed to the attack of −SN on the normal product (IV). The ambident reactivity of cation III has been compared with that of closely related cations, tris(methylthio)carboniumion and 2-methylamino-1,3-dithiolanylium ion (Ia). It was also found that the reaction of Ia with ethylthioxanthate anion (−SS′) afforded the S′-ethyl analog of IV (normal) together with a small amount of abnormal V. The
已经研究了 2-甲硫基-1,3-二硫基鎓离子 (III) 与 N,N-二甲基二硫代氨基甲酸盐阴离子 (-SN) 的反应,以证明阳离子 III 的环境特性。发现(i)反应得到S-β-(N,N-二甲基二硫代氨基甲酰基)乙基-S'-甲基三硫代碳酸酯(IV;正常)和亚乙基双(N,N-二甲基二硫代氨基甲酸酯)(V;异常);(ii) 在反应中形成甲基硫代黄原酸阴离子 (-SS);(iii) 异常产物(V)的形成更有利,这不能归因于-SN对正常产物(IV)的攻击。已将阳离子 III 的环境反应性与密切相关的阳离子、三(甲硫基)碳正离子和 2-甲氨基-1,3-二硫基烷鎓离子 (Ia) 的反应性进行了比较。
Extrusion Plasticity of a Butadiene-Acrylonitrile Rubber