化学学报 ›› 2012, Vol. 70 ›› Issue (06): 721-727.DOI: 10.6023/A1111022 上一篇    下一篇

研究论文

4,7-二(2-噻吩基)苯并噻二唑-3-辛基噻吩二炔的合成机理和电子结构的理论研究

张福兰, 万邦江, 徐伯华, 黄辉胜   

  1. 长江师范学院化学化工学院 重庆涪陵 408003
  • 收稿日期:2011-11-02 修回日期:2011-11-30 出版日期:2012-03-28 发布日期:2011-12-22
  • 通讯作者: 张福兰
  • 基金资助:

    重庆市教委科学技术资助项目(No. KJ091311).

Theoretical Study of Synthesis Mechanism and Electronic Structure for 3-Octylthien-2,5-ylenediethynylene-co-benzo[c]-1',2',5'- thiadiazo-3,6-ylenedi(2,5-thienylene)

Zhang Fulan, Wan Bangjiang, Xu Bohua, Huang Huisheng   

  1. College of Chemistry and Chemical Engineering, Yangtze Normal University, Fuling, Chongqing 408003
  • Received:2011-11-02 Revised:2011-11-30 Online:2012-03-28 Published:2011-12-22
  • Supported by:

    Project supported by the Natural Science Foundation of Education Committee of Chongqing (No. KJ091311).

采用密度泛函理论中的广义梯度近似(DFT/GGA)方法, 在PW91/DNP 水平上研究了4,7-二(2-噻吩基)苯并噻二唑-3-辛基噻吩二炔在PdCl2(PPh3)2 催化下的合成机理. 优化了反应过程中的反应物、中间体、过渡态和产物, 通过能量分析结果证实了中间体和过渡态的真实. 在同样的方法和精度研究了4,7-二(2-噻吩基)苯并噻二唑-3-辛基噻吩二炔在没有催化剂下的合成机理. 通过计算结果得到此反应在有PdCl2(PPh3)2 催化情况下的活化能小于没有催化剂情况下的活化能, 从而证明了PdCl2(PPh3)2 催化剂的催化活性. 采用密度泛函理论与周期性平板模型相结合的方法, 研究了产物P 在TiO2(100)表面的吸附, 通过Mulliken charge 和前线轨道分析表明: 当P 吸附在TiO2(100)表面时, P 向TiO2(100)表面转移0.692 e 电荷, 前线轨道能隙变窄. 理论预测的结果与实验值吻合.

关键词: 4,7-二(2-噻吩基)苯并噻二唑-3-辛基噻吩二炔, 密度泛函, 合成机理, 电子结构

The synthesis mechanism of 3-octylthien-2,5-ylenediethynylene-co-benzo[c]-1',2',5'-thiadiazo- 3,6-ylenedi(2,5-thienylene) with PdCl2(PPh3)2-catalyzed is investigated by density functional theory (DFT) at the GGA/PW91/DNP level. The geometric configurations of reactants, intermediates, transition states, and products are optimized. The energy analysis calculation approves the authenticity of intermediates and transition states. Additionally, the synthesis mechanism of 3-octylthien-2,5-ylenediethynylene-co-benzo[c]- 1',2',5'-thiadiazo-3,6-ylenedi(2,5-thienylene) without PdCl2(PPh3)2-catalyzed is studied employing the same functional and basis set. The computational results show that the activation barrier with PdCl2(PPh3)2- catalyzed is lower than the activation barrier without PdCl2(PPh3)2-catalyzed, which demonstrates that the catalyst of PdCl2(PPh3)2 possesses catalytic activity. Moreover, the density functional theory and periodic slab model are used to investigate the product (P) adsorption on TiO2(100) surface. The Mulliken charge and frontier orbital of the TiO2(100)-P are also discussed. The results reveal that the charge of 0.692 e transfers from the P to the TiO2(100) surface and the energy gap becomes narrow when the adsorption occurs. It is found that the above-mentioned theoretical calculations agree well with the experiment results.

Key words: 3-octylthien-2,5-ylenediethynylene-co-benzo[c]-1',2',5'-thiadiazo-3,6-ylenedi(2,5-thienylene), density functional, synthesis mechanism, electronic structure