非激活的Ni-催化还原性脱碳功能化:范围和机制见解
Wei Shu1, Andrés García-Domínguez1, M Teresa Quirós2
1Department of Chemistry , University of Zurich , Winterthurerstrasse 190 , Zurich CH 8057 , Switzerland.
Journal of the American Chemical Society
|August 22, 2019
概括
这项研究引入了使用两个电友碳源的新催化二碳功能化. 该方法通过基因机制有效地形成C(sp3) -C(sp3) 和C(sp3) -C(sp2) 键.
科学领域:
- 有机化学
- 催化剂
- 反应机制
背景情况:
- 氨酸是有机合成中的多功能构建块.
- 未被激活的氨酸的直接二碳功能化仍然具有挑战性.
- 开发选择性C-C键形成的方法至关重要.
研究的目的:
- 开发一种用于未激活的烯酸二碳功能化的新方法.
- 为了实现同时形成C ((sp3) -C ((sp3) 和C ((sp3) -C ((sp2) 键.
- 为了阐明反应机制.
主要方法:
- 催化减少二碳酸的功能化.
- 使用两个电友碳源.
- 使用四甲基氨基乙烯 (TDAE) 作为牺牲性减少剂.
- 控制实验和计算研究.
主要成果:
- 在不偏向的π系统中同时形成一个C(sp3) -C(sp3) 和一个C(sp3) -C(sp2) 键.
- 使用Ni催化剂和TDAE实现了精致的选择性.
- 涉及Ni (I) /Ni (III) 循环的基基机制的可行性.
- 证明了Ni () 种降低C () -sp3 () 键的能力.
- 在热力学上有利于将Ni (II) 减少为Ni (I).
结论:
- 开发的方法为olefin二碳功能化提供了一个强大的工具.
- 反应通过独特的基路进行.
- 了解机械细节可以控制选择性和产品形成.
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