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Isolating Free Carbenes, their Mixed Dimers and Organic Radicals
Published on: April 19, 2019
甲基碳-乙烯重组:一个实验和计算研究
Kathryn A Moore1, Jesus S Vidaurri-Martinez, Dasan M Thamattoor
1Department of Chemistry, Colby College, Waterville, Maine 04901, United States.
Journal of the American Chemical Society
|November 27, 2012
概括
一种新的光化学方法产生了zylidenecarbene,它重新排列到phenylacetylene. 这种反应完全有利于特定的转移,与以前的高温方法不同.
科学领域:
- 有机化学 有机化学
- 摄影化学的使用.
- 反应机制 反应机制
背景情况:
- 甲基基是一种反应性中间体.
- 关于碳重新排列的先前研究涉及高温热解.
- 了解碳烯的行为在有机合成中至关重要.
研究的目的:
- 为了研究光化学生成的zylidenecarbene的重新排列途径.
- 为了比较光化学生成与高温热解方法.
- 为了阐明碳转化为基的机制.
主要方法:
- 使用一种新型的光化学前体,1-化-1a,9b-二-1H-cyclopropa[l]phenanthrene.使用化的生成.
- 在环境温度下在酸中发生反应.
- 使用 (13) C 标记的碳来追踪反应途径.
- 使用B3LYP和CCSDT方法进行计算分析.
主要成果:
- 化的光化学生成导致了易于重新排列到乙烯.
- 碳不能被橄素捕获,这表明迅速重新排列.
- 贝塔碳的A (13) C标签仅出现在基乙烯中基环旁边的碳上.
- 计算研究支持观察到的H转移偏好.
- 结果与闪光真空热解相对比,显示标签杂乱.
结论:
- 光化学生成为zylidenecarbene重组提供了一个独特的途径.
- 反应过程中对转移的偏好很高.
- 这种光化学方法为研究碳中间体提供了对高温热解的可控替代方案.
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