碳氧化物辅助的C(sp3) -H激活在烯酸转化相关的复合物中
Jeffrey S Cannon1, Lufeng Zou, Peng Liu
1Arnold and Mabel Beckman Laboratory of Chemical Synthesis, Division of Chemistry and Chemical Engineering, California Institute of Technology , Pasadena, California 91125, United States.
Journal of the American Chemical Society
|April 16, 2014
概括
(II) 烯复合物通过协同的化-脱机制进行C-H激活. 这种碳酸盐辅助的过程涉及一个高度有序的过渡状态,由动态同位素效应证实.
科学领域:
- 有机金属化学 有机金属化学
- 催化剂是一种催化剂.
- 反应机制 反应机制
背景情况:
- ((II) 基烯复合物是氨酸转化过程中的关键中间体.
- 了解C-H激活机制对于催化剂设计和优化至关重要.
研究的目的:
- 阐明中C-H激活的详细机制 (II) 化复合物.
- 调查碳酸盐连接体在促进C-H激活中的作用.
主要方法:
- 低温合成二碳酸盐复合物用于直接观察C-H激活.
- 动力学研究包括初级动力同位素效应测量 (k ((H) /k ((D)).
- 计算建模以确定反应路径和过渡状态几何.
主要成果:
- 直接观察C-H激活步骤,独立于连接物交换.
- 第一阶动力学和负激活 (ΔS‡ = -5.2 ± 2.6 eu) 表明一个高度排序的过渡状态.
- 实验数据与计算的六环环机制一致,涉及碳酸盐辅助.
- 测量了一种显著的初级动态同位素效应 (k ((H) / k ((D) = 8.1 ± 1.7).
结论:
- 通过分子内协同的化-脱化机制进行C-H激活.
- 碳酸盐连接体起着至关重要的作用,采用伪形几何学来促进脱质.
- 催化剂性能可以通过对碳酸盐电子和联体环境的修改来调整.
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