对西兰氧化机制的量子化学研究
1Department of Chemistry, Grinnell College, Grinnell, Iowa 50112, USA. mader_mary@lilly.com
Journal of the American Chemical Society
|July 18, 2001
概括
量子化学计算揭示了有机氧化机制. 溶解显著改变了反应路径,有利于在二甲和甲醇等溶剂中添加过氧化离子以形成酒精.
科学领域:
- 有机金属化学 有机金属化学
- 计算化学的计算化学
- 反应机制研究 反应机制研究
背景情况:
- 有机素是有机合成中的多功能前体.
- 过氧化氧化是有机纤维素功能化的关键转化.
- 了解反应机制对于优化合成路径至关重要.
研究的目的:
- 为了比较不同机理的过氧化氧化有机酸盐到酒精.
- 为了研究溶解对这些反应路径的影响.
- 为了阐明阴离子五坐标酸盐中间体的作用.
主要方法:
- 量子化学计算被用来建模反应路径.
- 使用PCM溶解模型来模拟溶剂效应.
- 分析了不同的机械路径,以确定它们的能量有利性.
主要成果:
- 反应总是通过阴离子,五坐标酸盐物种进行.
- 与气相计算相比,溶解对反应概况产生了深刻的影响.
- 在CH(2)Cl(2) 和MeOH中,最有利的途径涉及过氧化离子添加到fluorosilane中,然后进行协调的迁移和氧化解离.
- 在气相中,H(2) O(2) 对五坐标酸的协调添加-迁移也是一个合理的机制.
结论:
- 溶解效应对于确定有机氧化物氧化的首选机制至关重要.
- 鉴定出来的机制为从有机纤维素中合成酒精提供了有价值的见解.
- 计算化学是解剖复杂反应通路的强大工具.
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