Formation of Electron-Donor-Acceptor Complex and 1,4-Cycloadduct of Tetracyanoethylene with Styrene and Its α- or β-Substituted Derivatives
作者:Yasuhiro Uosaki、Masaru Nakahara、Jiro Osugi
DOI:10.1246/bcsj.54.2569
日期:1981.9
EDA-complex formation and 1,4-cycloaddition of tetracyanoethylene (TCNE) with styrene,α-methylstyrene, 1,1 -diphenylethylene, cis-stilbene, and trans-stilbene were studied spectrophotometrically in chloroform at 25 °C. Formation constants of the EDA complexes were found to be in the order, trans-stilbene>styrene>α-methylstyrene>cis-stilbene>1,1-diphenylethylene. The difference in the formation constants
在 25 °C 的氯仿中,通过分光光度法研究了四氰基乙烯 (TCNE) 与苯乙烯、α-甲基苯乙烯、1,1-二苯基乙烯、顺式二苯乙烯和反式二苯乙烯的 EDA 络合物形成和 1,4-环加成。发现EDA配合物的形成常数为反式二苯乙烯>苯乙烯>α-甲基苯乙烯>顺二苯乙烯>1,1-二苯基乙烯。根据所研究的供体的电子和空间效应讨论了形成常数的差异。α-甲基苯乙烯和 1,1-二苯基乙烯比苯乙烯更快地热环加成到 TCNE。这表明在过渡态中发生了一些电荷分离。反式和顺式二苯乙烯不与 TCNE 反应的事实是根据 1,4-环加合物的稳定性差异来解释的,从 1,