波谱学杂志 ›› 1989, Vol. 6 ›› Issue (1): 71-76.

• 研究论文 • 上一篇    下一篇

N-溴代琥珀酰亚胺光解夺氢反应的ESR研究

曹涵, 刘扬, 王稳定, 徐广智, 梁任又   

  1. 中国科学院化学研究所, 北京
  • 收稿日期:1987-12-28 修回日期:1988-05-20 出版日期:1989-03-05 发布日期:2018-01-22
  • 基金资助:
    中国科技大学结构中心开放实验室资助

AN ESR STUDY ON THE PHOTOCHEMICAL HYDROGEN ABSTRACTION BETWEEN N-BROMOSUCCINIMIDE AND ALCOHOL OR HYDROCARBON

Cao Han, Liu Yang, Wang Wending, Xu Guangzhi, Liang Renyou   

  1. Institute of Chemistry, Academia Sinica, Beijing
  • Received:1987-12-28 Revised:1988-05-20 Online:1989-03-05 Published:2018-01-22

摘要: 本文用自旋捕捉剂亚硝基叔丁烷(MNP)和2,3,5,6-四甲基亚硝基苯与ESR相结合分别研究了N-溴代琥珀酰亚胺(NBS)光解反应产生的自由基,以及NBS与醇、取代芳烃及烷烃进行光解夺氢反应生成的活泼自由基中间体,结果表明:
1.在紫外光用下,NBS分子中的N-Br键发生均裂,产生N-中心自由基并为MNP所捕获.
2.对于醇及烷烃,NBS光解产生的Br能夺取叔碳原子上的氢,分别形成叔碳自由基HOR和R,并被ND所捕获.
3.与烷烃及醇不同的是:Br不仅能夺取烷基取代苯分子中叔碳原子上的氢,而且还能夺取仲碳原子上的氢,分别形成自由基PhCR2及PhCHR.

关键词: N-溴代琥珀酰亚胺, 光解, 夺氢, 电子自旋共振, 自旋捕捉

Abstract: Free radicals produced in the photolysis of N-Bromosuccinimide (NBS) or hydrogen abstraction reaction between Br. and alcohol or hydrocarbon have been studied by a combination of spin trapping technique and ESR spectrometer. The results show that:
1. Under the UV irradiation a homolytic cleavage of the N-Br bond in NBS occurs.
2. For alcohol and alkanc, the Br abstracted hydrogen on the tertiary carbon and tertiary carbon radical was formed.
3. For substituted benzene, Br abstracted hydrogen on the secondary or tertiary carbon and secondary or tertiary carbon radicals were formed.

Key words: N-bromosuccinimidc, Photolysis, Hydrogen abstraction, ESR, Spin trapping