波谱学杂志 ›› 1994, Vol. 11 ›› Issue (4): 383-390.

• 研究论文 • 上一篇    下一篇

硅(磷)中心自由基与2-丁烯二酸二乙酯的加合反应机理

郭金梁, 李勇   

  1. 清华大学化学系, 北京 100084
  • 收稿日期:1993-07-07 出版日期:1994-12-05 发布日期:2018-01-20

STUDING ON MECHANISM OF ADDITION REACTIONS OF Si-OR P-CENTERED RADICALS TO DIETHYL 2-BUTENEDIOATE

Guo Jinliang, Li Yong   

  1. Department of Chemistry, Qinghua University Beijing, 100084
  • Received:1993-07-07 Online:1994-12-05 Published:2018-01-20

摘要: 用ESR方法研究了硅(磷)中心自由基与2-丁烯二酸二乙酯的加合反应机理.具有顺式构型的马来酸二乙酯(DEM)与硅(磷)中心自由基反应,生成自由基加合物。DEM的聚合反应受到抑制。具有反式构型的富马酸二乙酯(DEF)易发生聚合反应,DEF与硅(磷)中心自由基的加合反应受到抑制.DEF与DEM在反应性能上的差异,主要来自DEF有较大的空间位阻效应.

关键词: 硅中心自由基, 磷中心自由基, 马来酸二乙酯, 富马酸二乙酯, 自由基加合反应, ESR

Abstract: The mechanism of the addition reactions Si-or P-centered radicals to diethyl 2-butenedioate has been studied by ESR method.Si-or P-centered radicals could be added to diethyl maleate which possesses cis-configuration.Hypertine splitting constants of the silyl radical adducts linked with different substituents were measured in our experiments. Radical polymerization of diethyl fumarate which possessetrans-configuration was initiated by radical Bu1O·and produeed telomer or polymer. The addition reactions of Si-or P-centered radicals to diethyl fumarate could not happen due to steric hindranee.

Key words: Si-centered radical, P-centered radical, Diethyl maleate, Diethyl fumarate, Kadical addition reaction, ESR