易斯酸触发了易斯基稳定末端的imido复合体的活性:C-H键激活,循环添加和脱化
Jiaxiang Chu1, Xianghao Han, Christos E Kefalidis
1State Key Laboratory of Organometallic Chemistry, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences , 345 Lingling Road, Shanghai 200032, P. R. China.
Journal of the American Chemical Society
|July 19, 2014
概括
一种新型的scandium imido复合物,被激活,产生一种不和的中间体. 这种中间体在室温下促进了循环添加,C-H激活和脱化等反应.
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.
背景情况:
- 稳定的扫-终端 imido 复合体是催化过程中有价值的前体.
- 金属结合体键的激活对于产生反应性中间体至关重要.
研究的目的:
- 为了研究使用酸激活一个扫末端的imido复合物.
- 为了探索由此产生的不和终端imido中间体的反应性.
- 用计算方法阐明关键转换的机制.
主要方法:
- 合成和表征一个稳定的scandium-terminal imido复合体.
- 介导激活生成一个不和的imido中间体.
- 对反应的实验研究,包括循环添加,C-H激活和脱化.
- 密度函数理论 (DFT) 对反应机制的研究.
主要成果:
- 酸成功激活了复合体,释放了4 - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - 甲基氨基胺.
- 不和的imido中间体在室温下与内部基 (循环添加),终端基 (C-H激活) 和替代化合物 (脱化) 反应.
- DFT计算证实了终端基和基的容易C-H激活.
- 获得了对C-H激活和脱化途径的机械洞察.
结论:
- 激活提供了一条有效的途径,使高反应性不和中介产物.
- 这些中间体具有广泛的反应性,在温和的条件下能够进行重要的合成转化.
- 计算研究为未来的催化剂设计提供了有价值的机械学理解.
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