有机化学 ›› 2016, Vol. 36 ›› Issue (3): 613-621.DOI: 10.6023/cjoc201508026 上一篇    下一篇

研究论文

InX3(X=F,Br)催化N-甲基吲哚与酮酸酯不对称合成机理的研究

王薇, 毛双, 彭丹, 李来才   

  1. 四川师范大学化学与材料学院 成都 610066
  • 收稿日期:2015-08-26 修回日期:2015-10-21 出版日期:2016-03-25 发布日期:2015-11-06
  • 通讯作者: 李来才 E-mail:lilcmail@163.com
  • 基金资助:

    四川省教育厅自然科学基金(No. 13ZA0150)和四川省科技厅自然科学基金(No. 2014JY0099)资助项目.

Investigation on the Mechanism for N-Methylindole and Keto Ester Catalyzed by InX3 (X=F, Br)

Wang Wei, Mao Shuang, Peng Dan, Li Laicai   

  1. College of Chemistry and Material Science, Sichuan Normal University, Chengdu 610066
  • Received:2015-08-26 Revised:2015-10-21 Online:2016-03-25 Published:2015-11-06
  • Supported by:

    Project supported by the Natural Science Foundation of Sichuan Province Department of Education (No. 13ZA0150) and the Natural Science Foundation of Sichuan Province (No. 2014JY0099).

采用密度泛函理论(DFT)中的B3LYP方法, 在B3LYP/6-31+G(d, p)基组水平上(In采用赝势基组LanL2DZ), 二氯乙烷(DCE)作为溶剂, 研究了InX3 (X=F, Br)催化N-甲基吲哚与酮酸酯不对称合成微观反应机理, 对反应通道上反应物、中间体、过渡态和产物进行了结构优化, 通过能量和振动频率分析以及内禀反应坐标(IRC)计算证实了过渡态和中间体的合理性, 并且在相同基组水平上, 通过自然键轨道(NBO)理论和原子理论(AIM)分析了分子轨道间的相互作用及成键特点. 结果发现: 在InF3催化作用下, N-甲基吲哚与酮酸酯反应形成1,2-加成产物和1,4-加成产物的反应速控步骤活化能分别为25.62和12.52 kcal/mol, 在InBr3催化作用下, N-甲基吲哚与酮酸酯反应形成1,2-加成产物和1,4-加成产物的反应速控步骤活化能分别为26.87和13.95 kcal/mol. 比较研究结果, InF3能有效催化该反应的进行, 且1,4-加成产物更容易生成, 我们的研究结果与实验结果相吻合. 还采用连续介质模型(PCM)比较了5种溶剂化作用对反应的影响, 可以预测: 二甲亚砜(DMSO)溶剂条件下, InF3催化1,4-加成产物的产率会更高.

关键词: 密度泛函理论, N-甲基吲哚, 反应机理, 溶剂化

The reaction mechanism for N-methylindole and keto ester catalyzed by InX3 (X=F, Br) was studied by the density functional theory (DFT). The geometries and the frequencies of reactants, intermediates, transition states, and products have been calculated at the B3LYP/6-31+G(d, p) level, dichloroethane (DCE) is used as a solvent and the LanL2DZ basis has been used for In atom. Transition states have been confirmed by the corresponding vibration analysis and intrinsic reaction coordinate (IRC). In addition, nature bond orbital (NBO) and atoms in molecules (AIM) theories have been used to analyze orbital interactions and bond natures. The results showed that the activation energies of rate-determining steps in which N-methylindole reacted with keto ester to form 1,2-adduct and 1,4-adduct were 25.62 and 12.52 kcal/mol catalyzed by InF3 while those were 26.87 and 13.95 kcal/mol when the reaction was catalyzed by InBr3 under the same conditions. Comparing the results of our research, InF3 can effectively catalyze the reaction, and the 1,4-adduct was more likely to be produced. The final result of our theory study agreed with the experimental data, meanwhile, self-consistent reaction field (SCRF) was carried out using the polarized continuum model (PCM) at the same theoretical level for geometry optimizations and frequency calculations in five different salvations. We predicted that the productivity to form 1,4-adduct was more higher catalyzed by InF3 in the solvent of dimethyl sulfoxide (DMSO).

Key words: density functional theory, N-methylindole, reaction mechanism, solvation