物理化学学报 >> 1985, Vol. 1 >> Issue (04): 329-334.doi: 10.3866/PKU.WHXB19850406

研究论文 上一篇    下一篇

芳基重氮盐及其冠醚络合物光解活泼自由基的ESR研究

徐广智; 赵瑶兴; 孙祥玉; 刘扬; 宋心琦   

  1. 中国科学院化学研究所, 北京; 清华大学化学化工系, 北京
  • 收稿日期:1984-11-20 修回日期:1985-02-27 发布日期:1985-08-15

ESR STUDY ON THE ACTIVE RADICALS PRODUCED BY THE PHOTOLYSIS OF ARENEDIAZONIUM SALTS AND THEIR CROWN ETHER COMPLEXES

Xu Guangzhi; Zhao Yaoxing; Suen Xiangyu; Liu Yang; Song Xinqi   

  1. Institute of Chemistry, Academic Sinica, Beijing; Chmistry and Chemical Engineering Department, Qinghua University, Beijing
  • Received:1984-11-20 Revised:1985-02-27 Published:1985-08-15

摘要: 本文用自由基捕捉剂2,3,5,6-四甲基亚硝基苯(ND)及苯亚甲基叔丁基氮氧化物(PBN)与ESR相结合的方法研究了芳基重氮盐RC_6H_4N~+_2BF~-_4(R=F, Cl, Br, I, NO_2, COOH,OCH_3及H)及其与18-冠-6、二苯并-24-冠-8的络合物在苯中的光解过程。结果表明它们光解产生了活泼自由基RC_6H_4并可被ND及PBN捕捉....

Abstract: Free radicals produced by the photolysis processes of arenediazonium salts and their crown ether complexes have been investigated by combination of spin trapping technique and ESR spectrometry. The results show that the active radicals R-C_6H_4 are produced during the course of photolysis of these compounds and can be trapped by spirt trapping reagents phenyl tert-butyl nitrone (PBN) and nitrosodurene (ND) to form spin adduets Ⅰ, Ⅱ, Ⅲ, Ⅳ and Ⅴ.
In the cases of Ⅰ, Ⅱ, Ⅲ, and Ⅳ the effects of different substitue R at the same ring position on a_N are in the order of
o—R OCH_3>H>Br≥Cl
m—R H>Br≥Cl
p—R OCH_3>H>I≥Br≥Cl>NO_2
and the effects of same substituent at different ring position on a_N are in the order of
o—R≥p—R>m—R
The role of crown ether is favourable to the trapping of active radicals.