甲基二氧化C-H的分子动力学
Zhongyue Yang1, Peiyuan Yu1, K N Houk1
1Department of Chemistry and Biochemistry, University of California , Los Angeles, California 90095, United States.
Journal of the American Chemical Society
|March 12, 2016
概括
分子动力学模拟显示,二甲基二氧化 (DMDO) 与异布的反应有利于在乙溶剂中的氧气反弹. 这条通往三醇和乙的途径,由于无障碍过渡,在溶液中变得非常有效.
科学领域:
- 物理化学
- 计算化学
- 反应动力学
背景情况:
- 甲基二氧化 (DMDO) 是一种强烈的氧化剂.
- 了解DMDO反应机制对于合成化学至关重要.
- 抽取原子是DMDO反应的一个关键步骤.
研究的目的:
- 通过分子动力学研究DMDO与异布的反应途径.
- 阐明溶剂对DMDO反应结果的影响.
- 描述涉及的过渡状态和中间物种.
主要方法:
- 进行分子动力学模拟.
- 使用隐性乙溶剂模型 (SMD).
- 分析反应轨迹以确定产品的分布和中间寿命.
主要成果:
- 在气相中,只有10%的反应轨迹遵循氧气反弹路径.
- 在隐性乙溶剂中,氧气反弹路径提高到90%的效率.
- 在乙溶液中,氧气反弹路径变得无障碍.
- 观察到短寿命的二基中间体,其中C-H键破裂到C-O键形成发生在30-150 fs内.
结论:
- 溶剂效应显著影响DMDO与异布的反应结果.
- 乙溶剂显著提高了氧气反弹路径的效率.
- 观察到的C-O键形成的时间尺度与相似的激素对寿命的实验数据一致.
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