催化C-H氨基化介于迪皮林科巴尔特伊米多斯
Yunjung Baek1, Theodore A Betley1
1Department of Chemistry and Chemical Biology , Harvard University , 12 Oxford Street , Cambridge , Massachusetts 02138 , United States.
Journal of the American Chemical Society
|April 25, 2019
概括
这项研究引入了一种新型的 (I) 合成,可促进高效的C-H氨化催化. (III) imido复合物,特别是与二协调在一起时,表现出增强的反应性和用于C-H键功能化的催化周转.
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.
- 合成化学 合成化学
背景情况:
- 开发用于催化应用的新型过渡金属复合物.
- 在C-H功能化反应中探索复合物.
- 了解像物种的反应性.
研究的目的:
- 为了合成和表征一种新的 (((I) synthon.
- 在C-H氨基化中研究 (III) imido复合物的反应性.
- 为了阐明催化C-H氨化过程的机制.
主要方法:
- 使用石墨将 (II) 复合物降解为 (II) 合成物.
- 用酸处理 (I) 复合物以形成 (III) imido复合物.
- 单晶X射线衍射用于结构确认.
- 在H NMR定位实验中,研究二胺协调.
- 动态研究,包括动态同位素效应实验,以探测反应机制.
主要成果:
- 成功合成了一种新型的 (I) 合成物, (Ar) Co (I).
- 形成三坐标的 (III) 胺复合体, (ArL) Co (NR).
- 观察分子内C-H氨基化导致pyrrolidine的形成.
- 皮里丁与 ((III) imido复合物的协调增强了C-H氨化反应性和催化周转率.
- 动力学研究表明,C-H氨基化有两步激素路径.
结论:
- 新型 (I) 合成是 (III) 模态复合物的多功能前体.
- 皮里丁结合的 ((III) imido复合物是C-H氨基化的高效催化剂.
- 增强的反应性归因于更高的自旋状态群体和降低的水晶场在皮里丁协调.
- 这项研究通过激素途径提供了对催化C-H氨化机制的见解.
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