亚氧化物到氧化物的二分化是逐步通过dinitrosoalkene diradicals:一个密度函数理论研究研究
Zhi-Xiang Yu1, Pierluigi Caramella, K N Houk
1Department of Chemistry and Biochemistry, University of California, Los Angeles, CA 90095-1569, USA.
Journal of the American Chemical Society
|December 11, 2003
概括
密度函数理论揭示,氧化二氧化物的二分化到furoxans通过二基中间体逐步进行. 芳香性亚氧化物由于在C-C键形成过程中被中断的结合而变质较慢.
科学领域:
- 计算化学计算化学
- 有机反应机制 有机反应机制
背景情况:
- 氧化物是多功能合成中间体.
- 通过氧化二元化形成氧化物是关键反应.
研究的目的:
- 为了阐明乙二氧化和准二氧化二聚变的机制.
- 为了研究二基中间体在素形成中的作用.
- 了解影响芳香氧化物二聚化速率的因素.
主要方法:
- 密度函数理论 (DFT) 的计算.
- B3LYP/6-31G* 计算级别. 这是一个很大的问题.
- 对反应路径和中间体特性进行分析.
主要成果:
- 分解发生阶段性,形成具有显著的二基基性质的丁醇基中间体.
- 在这两种反应中,形成C-C键是决定速度的关键阶段.
- 芳香氧化物由于在C-C键形成过程中被中断的结合而表现出较慢的二元化.
- 单环furoxans的异构化可能是通过二基基的机制进行的.
结论:
- 氧化二氧化物的二元化到furoxans涉及二基中间体.
- 芳香系统中的电子效应会影响反应速率.
- DFT为复杂的有机反应机制提供了宝贵的见解.
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