物理化学学报 >> 2011, Vol. 27 >> Issue (09): 2043-2050.doi: 10.3866/PKU.WHXB20110921

理论与计算化学 上一篇    下一篇

AuClx (x=1, 3)催化2-炔丙基苯酮与苯炔环化反应机理

朱元强1, 郭建春2, 叶仲斌1   

  1. 1. 油气藏地质及开发工程国家重点实验室, 西南石油大学化学化工学院, 成都 610500;
    2. 西南石油大学石油工程学院, 成都 610500
  • 收稿日期:2011-05-09 修回日期:2011-07-07 发布日期:2011-08-26
  • 通讯作者: 朱元强 E-mail:yqzhu@swpu.edu.cn
  • 基金资助:

    四川省教育厅科研项目(09ZB099)资助

AuClx (x=1, 3)-Catalyzed Benzannulation Mechanisms between 2-Propynyl-hypnone and Benzyne

ZHU Yuan-Qiang1, GUO Jian-Chun2, YE Zhong-Bin1   

  1. 1. State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation, School of Chemistry and Chemical Engineering,Southwest Petroleum University, Chengdu 610500, P. R. China;
    2. School of Petroleum Engineering, Southwest PetroleumUniversity, Chengdu 610500, P. R. China
  • Received:2011-05-09 Revised:2011-07-07 Published:2011-08-26
  • Contact: YE Zhong-Bin E-mail:yqzhu@swpu.edu.cn
  • Supported by:

    The project was supported by the Scientific Research Fund of Sichuan Provincial Education Department, China (09ZB099).

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摘要： 对金属元素Au采用LanL2DZ基组, 对非金属元素C, H, O, Cl 采用6-31G*和6-311++G**基组, 用密度泛函理论的B3LYP、B3PW91、UB3LYP方法和二阶微扰理论MP2 方法研究了不同氧化态的金催化剂催化2-炔丙基苯酮与苯炔环化反应的机理. 结果表明: 在AuCl和AuCl3的作用下, 反应均能通过[4+2]和[3+2]途径生成产物. 但在AuCl 催化下, [4+2]反应途径比[3+2]反应途径具有更低的活化自由能, 反应主要通过[4+2]途径进行; 而在AuCl3催化下, [4+2]反应途径与[3+2]反应途径的活化自由能相近, 反应通过两条途径竞争生成产物. 比较AuCl 和AuCl3的催化效果发现, 不同氧化态的金催化剂改变了反应的机理, 该反应的活化自由能在AuCl 作用下比在AuCl3作用下低11.18 kJ·mol-1. 对于该反应, AuCl表现出了更好的催化活性. 这些计算结果和实验现象相吻合.

关键词: 金催化剂, 密度泛函理论, 反应机理, [4+2]环化途径, [3+2]环化途径

Abstract: The AuClx (x=1, 3)-catalyzed benzannulation mechanisms between benzyne and 2-propynylhypnone were investigated using B3LYP, B3PW91, UB3LYP, and the second-order Møller-Plesset perturbation (MP2) methods with the LanL2DZ basis set for Au and the 6-31G*, 6-311++G** basis sets for C, H, O, Cl. For the AuCl or AuCl3 catalysts the reaction occurs through both the [4 + 2] and the [3 + 2] benzannulation pathways to yield the product. With AuCl, the reaction occurs mainly through the [4 + 2] reaction pathway because of this pathway's low activation free energy. With AuCl3, the reaction occurs by the [4+2] and the [3+2] reaction pathways. These two pathways are competitive because of their close activation free energies. An analysis of these results indicates that the gold oxidation states change the reaction mechanisms and greatly influence the reaction barriers. The calculated results indicate that the AuCl catalyst is more effective than AuCl3 because in the reaction catalyzed by AuCl the activation free energy of the rate determining step is 11.18 kJ·mol-1 lower than that of the reaction catalyzed by AuCl3. These results are in good agreement with the experimental observations.

Key words: Gold catalyst, Density functional theory, Reaction mechanism, [4+2] Benzannulation, [3+2] Benzannulation