乙烯基酸 - 酸重排列:危周期性[1,3] - 符号转移还是没有?
Rosa E Bulo1, Andreas W Ehlers, Stefan Grimme
1Department of Chemistry, FEW, Vrije Universiteit, De Boelelaan 1083, 1081 HV Amsterdam, The Netherlands.
Journal of the American Chemical Society
|November 15, 2002
概括
密度函数理论揭示了2-乙烯酸经历[1,3]-信号转移,形成3-酸,其能量障碍比碳化合物类似物更低. 与Cr ((CO) ((5) 的复合进一步稳定了这些重新排列.
科学领域:
- 有机金属化学 有机金属化学
- 计算化学计算化学
- 有机反应机制 有机反应机制
背景情况:
- [1,3]-sigmatropic转移是有机化学的一个基本反应.
- 与它们的碳类似物相比,含的异环环具有独特的反应性.
- 金属复杂化可以显著改变反应路径和能量.
研究的目的:
- 为了研究2 - 乙烯基酸的[1,3] - 西格马特罗普重新排列,并将其与乙烯基cyclopropane系统进行比较.
- 阐明Cr (Cr) CO (CO) (5) 复合对重排障碍和机制的影响.
- 用计算方法分析这些转换的立体化学结果和能量概况.
主要方法:
- 密度函数理论 (DFT) 的计算被用来绘制潜在能量表面.
- 对于各种途径,确定了过渡状态和反应障碍.
- 使用多引用方法来验证DFT衍生的激活能量.
主要成果:
- 通过协同的环周[1,3]-信号转移,2-维尼尔酸重新排列为3-酸,其屏障比维尼尔cyclopropane更低.
- ) 复合稳定了素系统,降低了重排障碍,特别是对抗异构体.
- 在中发生的表皮化是通过类似于二根基的环开环闭机制发生的.
- 一个P-基组的存在会影响受益途径,与实验观测一致.
结论:
- 2 - 乙烯基酸的[1,3] - 符号转基因重组是一个环周过程,与乙烯基烯酸的二基基类似机制不同.
- 通过稳定中间体和降低激活能,Cr (CO) (5) 复合显著促进了重组.
- 计算研究为这些有机重组的机制和立体选择性提供了宝贵的见解.
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