高等学校化学学报 ›› 2009, Vol. 30 ›› Issue (5): 1010.

• 研究论文 • 上一篇    下一篇

双取代铵氧化物(R2HNO)与双取代羟胺(R2NOH)的相互转换机制的理论研究——取代基的电负性和立体效应影响

石国升, 丁益宏   

  1. 吉林大学理论化学研究所, 理论化学计算国家重点实验室, 长春 130023
  • 收稿日期:2008-01-23 出版日期:2009-05-10 发布日期:2009-05-10
  • 通讯作者: 丁益宏, 男, 博士, 教授, 博士生导师, 主要从事量子化学理论研究, E-mail: yhdd@mail.jlu.edu.cn

Theoretical Studies on the Conversion Mechanism Between Double-substituted Ammonium Oxides(R2HNO) and Double-substituted Hydroxylamines(R2NOH)——Electronegativity and Steric Effects of Substituents

  1. State Key Laboratory of Theoretical and Computational Chemistry, Institute of Theoretical Chemistry, Jilin University, Changchun 130023, China
  • Received:2008-01-23 Online:2009-05-10 Published:2009-05-10
  • Contact: DING Yi-Hong, E-mail: yhdd@mail.jlu.edu.cn

摘要:

在B3LYP/6-311++G(d,p)水平下, 对一系列双取代铵氧化物(R2HNO)与双取代羟胺(R2NOH){R=NH2, N(CH3)2, N(CH2CH3)2, N[C(CH3)3]2, OH, OCH3, OCH2CH3, OC(CH3)3}的相互转换机制进行了理论研究. 研究结果表明, 双取代铵氧化物R2HNO的热力学和动力学稳定性受电负性和立体效应的综合控制. 其中胺基系列热力学稳定性以空间位阻的影响为主, 而烷氧基系列热力学稳定性以电负性的影响为主. 而两者的动力学稳定性均以电负性影响为主.

关键词: 双取代铵氧化物, 双取代羟胺, 热力学稳定性, 动力学稳定性

Abstract:

At the B3LYP/6-311++G(d,p) level, we studied the conversion mechanism between the double-substituted ammonium oxides(R2HNO) and double-substituted hydroxylamines(R2NOH) with R=NH2, N(CH3)2, N(CH2CH3)2, N[C(CH3)3]2, OH, OCH3, OCH2CH3 and OC(CH3)3. It was shown that the thermodynamic and kinetic stability of the double-substituted ammonium oxides R2HNO are co-controlled by the electronegativity and steric effects. Amongst, the thermodynamic stability of amino-substituted species is dominated by steric effect, whereas that of the alkoxy-substituted species is dominated by electronegativity. The kinetic stability of both amino- and alkoxy-substituted species is mainly influenced by electronegativity.

Key words: R2HNO, R2NOH, Thermodynamic stability, Kinetic stability

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