化学学报 ›› 2012, Vol. 70 ›› Issue (12): 1347-1354.DOI: 10.6023/A1111211 上一篇    下一篇

研究论文

碱(土)金属离子与2-(3′-羟基-2′-吡啶基)苯并噁唑阳离子-π 复合物及其分子内质子转移过程的理论研究

易平贵, 刘峥军, 汪朝旭, 侯博, 于贤勇, 李筱芳   

  1. 湖南科技大学化学化工学院 理论化学与分子模拟省部共建教育部重点实验室 分子构效关系湖南省普通高等学校重点实验室 湘潭 411201
  • 投稿日期:2011-11-21 修回日期:2012-04-20 发布日期:2012-04-20
  • 通讯作者: 易平贵 E-mail:yipinggui@sohu.com
  • 基金资助:

    国家自然科学基金(Nos. 21172066, 20772027)湖南省自然科学基金(Nos. 10JJ4011, 11JJ2007)和湖南省高校创新平台开放基金(No. 09K081).

Alkali (Alkali Earth) Metal Ions with 2-(3'-Hydroxy-2'-pyridyl)benzoxazole Cation-π Complexes and Its Intramolecular Proton Transfer Process: A Theoretical Investigation

Yi Pinggui, Liu Zhengjun, Wang Zhaoxu, Hou Bo, Yu Xianyong, Li Xiaofang   

  1. Key Laboratory of Theoretical Chemistry and Molecular Simulation of Ministry of Education, Hunan Province College Key Laboratory of QSAR/QSPR, School of Chemistry and Chemical Engineering, Hunan University of Science and Technology, Xiangtan 411201
  • Received:2011-11-21 Revised:2012-04-20 Published:2012-04-20
  • Supported by:

    Project supported by the National Natural Science Foundation of China (Nos. 21172066, 20772027), Hunan Provincial Natural Science Foundation of China (Nos.10JJ4011, 11JJ2007), Scientific Research Fund of Hunan Provincial Education Department (No. 09K081).

采用密度泛函B3LYP 方法, 在6-311++G(d,p)基组水平上对碱(土)金属离子(Li+, Na+, K+, Be2+, Mg2+和Ca2+)与2-(3'-羟基-2'-吡啶基)苯并噁唑(HPyBO)的36 种阳离子-π 复合物的初始构型进行了几何全优化, 并计算了其相互作用能. 结果表明, 碱(土)金属离子与HPyBO 复合物有较强的阳离子-π 相互作用, 部分复合物甚至达到了化学键的强度.相对能量的变化表明碱(土)金属离子的作用能改变HPyBO 分子内质子转移过程的能垒, 甚至可以导致优势构型反转.当考虑水的溶剂效应后, 各质子转移异构体的相对能量及质子转移的能垒均有一定程度的改变. 另外, 应用分子中的原子(AIM)方法对复合物分子内氢键的键临界点性质进行了分析.

关键词: 密度泛函理论(DFT), 阳离子-π 相互作用, 分子内质子转移, 自然键轨道理论(NBO), 分子中的原子理论(AIM)

The structures of 2-(3'-hydroxy-2'-pyridyl)benzoxazole (HPyBO) with alkali (or alkaline earth) metal ions (Li+, Na+, K+, Be2+, Mg2+ and Ca2+) were fully optimized at the 6-311++G(d,p) level by using B3LYP density functional theory and the binding energies were calculated at the same level. The result shows that the cation-π interaction between alkali (or alkaline earth) metal ions and HPyBO complexes are very strong, some of the interactions are even comparable to chemical bonding. The relative energies show that cation-π interaction can change the energy barrier of intramolecular proton transfer. When considering the solvent effect of water, the relative energies of isomers and the energy barrier of intramolecular proton transfer are changed to some extent. In addition, the properties at the BCPs (bond critical points) of intramolecular hydrogen bond in the complexes are also discussed.

Key words: density functional theory (DFT), cation-π interaction, intramolecular proton transfer, natural bond orbital (NBO), atoms in molecules (AIM)