关于允许和禁止的电循环反应的21世纪观点
Qingyang Zhou1, Garrett Kukier1, Igor Gordiy1
1Department of Chemistry and Biochemistry, University of California, Los Angeles, California90095, United States.
The Journal of organic chemistry
|December 28, 2023
概括
伍德沃德-霍夫曼规则解释了电循环反应的立体化学. 计算研究证实了这些规则,并揭示了正式禁止的反应的新途径,突出了计算化学的影响.
科学领域:
- 有机化学 有机化学
- 理论化学 理论化学
- 量子化学 是一个量子化学.
背景情况:
- 1965年提出的伍德沃德-霍夫曼规则预测了电循环反应的立体化学.
- 由Longuet-Higgins和Abrahamson引入的相关性图,通过匹配轨道对称性来解释立体选择性.
- 霍夫曼和伍德沃德将这些图表应用于阐明循环加法机制.
研究的目的:
- 用先进的计算方法研究电循环反应.
- 检查边境分子轨道及其对称性相关性.
- 探索极化系统中正式禁止的反应的低能途径.
主要方法:
- 密度函数理论 (DFT) 的计算.
- 完成活动空间自相一致场 (CASSCF) 的计算.
- 沿着内在反应坐标和建模轨迹跟踪边界分子轨道.
主要成果:
- 对热禁止系统检查了最高占用分子轨道 (HOMO) 和最低不占用分子轨道 (LUMO) 之间的相关性.
- 在高度极化,捐赠者-接受者替代系统中对电循环的研究.
- 鉴定由于诱导的zwitterionic特性而被正式禁止的反应的低能途径.
结论:
- 计算研究支持并完善对伍德沃德-霍夫曼规则的理解.
- 关于"违法行为"的概念. 没有任何!" 是重新审视和澄清的.
- 计算在所有化学学科中越来越有影响力.
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