阻碍了奇拉离子双极对的逆转
A Filippi1, F Gasparrini, M Speranza
1Contribution from the Dipartimento di Studi di Chimica e Tecnologia delle Sostanze Biologicamente Attive, Università degli Studi di Roma "La Sapienza", P.le A. Moro 5, I-00185 Roma, Italy.
Journal of the American Chemical Society
|July 18, 2001
概括
气相甲基化S-(-) -1-乙醇产生O-质子化S-(-) -1--1-甲基乙烯. 它的解离动力学和分子内反转显示了与水溶液相比的差异,突出显示了溶剂对反应通路的影响.
科学领域:
- 物理有机化学 有机化学
- 反应动力学 反应动力学
- 离子 - 溶剂相互作用
背景情况:
- 通过气相甲基化生成的O质子化S-(-) -1--1-甲基乙 (IS).
- 这项研究研究了在IS.的C-O键解离后形成的亲密离子双极对 (IIS).
- 将气相IIS行为与水溶液中的观察结果进行比较.
研究的目的:
- 阐明亲密的离子双极对 (IIS) 的重组动态.
- 将气相反应机制与水溶液中的反应机制进行比较.
- 了解溶剂相互作用对分子内逆转和解离的影响.
主要方法:
- 在IS.中对分子内部结构逆转的动力学研究.
- 分析IS到α-甲基基离子和甲醇的解离途径.
- 气相离子双极对行为与溶液相溶解分析的比较.
主要成果:
- 通过动力学分析研究了IS的气相解离动态.
- 在溶液中阻碍IS的反转归因于有吸引力的溶剂-溶解物相互作用.
- 在水溶液中,溶剂交换可以防止IS中的光学活性丧失.
结论:
- 溶剂相互作用显著影响密切的离子双极对的内部回报.
- 气相反应路径与溶液相反应路径不同,原因是没有溶剂效应.
- 该研究提供了关于分子结构,反应动力学和溶剂环境之间的相互作用的见解.
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