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Isolating Free Carbenes, their Mixed Dimers and Organic Radicals
Published on: April 19, 2019
3-三甲基基环丁烯.三甲基基环基. 对碳的 γ 作用
1Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, Indiana 46556, USA. creary.1@nd.edu
Journal of the American Chemical Society
|March 27, 2013
概括
3-三甲基基环丁烯通过1,3-迁移,而不是基迁移,重组为1-三甲基基环丁. 计算分析显示,稳定的碳化合物构造有利于这种途径.
科学领域:
- 有机化学 有机化学
- 计算化学计算化学
背景情况:
- 碳化合物化学对于有机合成至关重要.
- 了解碳重新排列机制,可以了解反应途径.
研究的目的:
- 为了研究3-三甲基基环丁烯的重新排列机制.
- 阐明影响碳反应性和产品分布的因素.
主要方法:
- 一种托西尔化盐的热解,以产生碳素.
- 标记研究来追踪原子迁移.
- 计算研究 (DFT) 用于分析碳化合物构造和过渡状态.
主要成果:
- 碳二氧化解的主要产物是1-trimethylsilylbicyclobutane.
- 标签研究证实1,3-迁移是主要的途径.
- 计算分析发现一种低能碳化合物构成,通过与C-Si键的相互作用稳定,阻碍了silyl迁移.
结论:
- 观察到的重新排列主要是由1,3-迁移驱动的,这是由于碳的首选构造中的硬质和电子因素.
- 在甲醇中的光化学生成会导致碳酸介质,而在二甲基胺中的反应则涉及在碳酸中心的核友性攻击.
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