大学化学 >> 2016, Vol. 31 >> Issue (1): 68-74.doi: 10.3866/pku.DXHX20160168

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从轨道对称守恒原理看Diels-Alder反应区域选择性

袁耀锋,王文峰*()   

  • 发布日期:2016-01-28
  • 通讯作者: 王文峰 E-mail:wangwf@fzu.edu.cn
  • 基金资助:
    福建省自然科学基金(2013J01361);福建大学高等教育教学改革工程项目

A Viewpoint on the Regioselectivity of Diels-Alder Reaction Based on the Principle of Conservation of the Orbital Symmetry

Yao-Feng YUAN,Wen-Feng WANG*()   

  • Published:2016-01-28
  • Contact: Wen-Feng WANG E-mail:wangwf@fzu.edu.cn
  • Supported by:
    福建省自然科学基金(2013J01361);福建大学高等教育教学改革工程项目

摘要:

根据轨道对称守恒原理(PCOS),推断出决定Diels-Alder反应的区域选择性的轨道相互作用是双烯体与亲双烯体各自最稳定的价轨道之间的相互作用,这种相互作用形成的是反应产物的两根新σ键中能量更低的σ键,即σ1键。在过渡态中具有更稳定的σ1键的那个区域异构体将是反应的优势产物,本文将这个规则称为σ1规则。本文的量子化学计算结果既证实了σ1规则预测Diels-Alder反应区域选择性主产物的正确性,也证实了σ1键的确来自于双烯体与亲双烯体各自最稳定的价轨道之间的相互作用。

关键词: Diels-Alder反应, 轨道对称守恒原理, 区域选择性, 轨道相互作用

Abstract:

Based on the principle of conservation of orbital symmetry(PCOS), it can be concluded that it is the interaction between the most stable valent orbitals of diene and dienophile that determines the regioselectivity of the Diels-Alder reaction, which produces the more stable σ1 bond of the two formed σ bonds.The regioisomer which possesses more stable σ1 bond in transition state will be the main product of the Diels-Alder reaction, which is called σ1 rule in this paper.The correctness to predict the main product of Diels-Alder reaction by using σ1 rule has been confirmed by quantum-chemical calculation, and the calculation also proves that the σ1 bond forms between the most stable valent orbital of the individual reactants, diene and dienophile.

Key words: Diels-Alder reaction, Principle of conservation of orbital symmetry, Regioselectivity, Orbital interaction

MSC2000: 

  • O621.1