2,6-二甲基吡啶与1-己烯反应烯烃插入过程的理论研究

Theoretical Study on Olefin Insertion Process of 2,6-Dimethylpyridine with 1-Hexene

本论文使用密度泛函理论详细研究了2,6-二甲基吡啶与1-己烯反应的烯烃插入过程。计算结果表明,与2,1-插入路径相比,1,2-插入路径具有较低的插入能垒和较好的热力学性质。1,2-插入模式下,si面插入比re面插入在动力学和热力学上更为有利。电子因素在区域选择性的实现中起着至关重要的作用。最可行路径中关键过渡态的稳定性,可归因于1-己烯与阳离子钇催化剂之间较强的相互作用和电荷交替现象。

In this paper,density functional theory is used to investigate the olefin insertion process of 2,6-lutidine and 1-hexene in detail.The calculation results show that lower energy barrier and favorable thermodynamics are found for the 1,2-insertion pathway in comparison with 2,1-insertion pathway.In 1,2-insertion mode,si-face insertion is more favorable than re-face insertion both kinetically and thermodynamically.It has been revealed that electronic factors play a crucial role in achieving regioselectivity.The stability of the key transition state involved in the most feasible pathway could be ascribed to the stronger interaction between 1-hexene and cationic yttrium catalyst and the charge alternation.