物理化学学报 >> 1995, Vol. 11 >> Issue (06): 516-520.doi: 10.3866/PKU.WHXB19950608

研究论文 上一篇    下一篇

取代基对氮和氧自由基稳定性影响的理论研究

俞庆森,蔡国强   

  1. 浙江大学化学系|杭州 310027
  • 收稿日期:1994-06-22 修回日期:1994-10-18 发布日期:1995-06-15
  • 通讯作者: 蔡国强

A Quantum Chemistry of the Effect of the Substituents on the Stabilization of Nitrogen-centered and Oxygen-centered Radical

Yu Qing-Sen,Cai Guo-Qiang   

  1. Department of Chemistry,Zhejiang University,Hangzhou 310027
  • Received:1994-06-22 Revised:1994-10-18 Published:1995-06-15
  • Contact: Cai Guo-Qiang

摘要:

用MNDO方法,全构型优化,研究了15个氮自由基4-RC6H4NH,和15个氧自由基4-RC6H4O(R=-H;-OCH3,-Cl,-F,-CN,-COCH3,-NO2,-CH3,-CF3,-SCH3,-C6H5,-Nh2,-BH2,-PH2,-SiH3)的稳定化能.结果表明:-NH2,-CH3,-OCH3,-F基团对自由基起稳定化作用,-CF3,-NO2;-CN,-COCH3,-BH2基团对自由基起去稳定化作用.苯基对氧自由基有较大的稳定化作用,而对氮自由基的稳定性影响较小.-SCH3,-PH2,-SiH3,-Cl基团表现弱的去稳定化作用.计算和实验结果基本相符.

关键词: 自由基, MNDO计算, 稳定化能

Abstract:

The stabilization of fifteen nitrogen-centered radicals 4-RC6H4NH and fifteen oxygen-centered radicals 4-RC6H4O (R=-H, -OCH3, -Cl, -F, -CN, -COCH3, -NO2,-CH3, -CF3, -CH3S, -C6H5, -NH2, -BH2, -PH2, -SiH3) have been studied with MNDO method. The substituents of -NH2 , -CH3, -OCH3, -F play a role of stabilization on radical, -CF3, -NO2, -CN, -COCH3, -BH2 play a role of de-stabilization and -SCH3, -PH2,-SiH3, -Cl play a role of weak de-stabilization. Benzyl only play a role of stabilization on oxygen-centered radicals.

Key words: Radicals, MNDO calculation, The energy of stabilization