Ni-Catalyzed Reductive Dicarbofunctionalization of Nonactivated Alkenes: Scope and Mechanistic Insights
作者:Wei Shu、Andrés García-Domínguez、M. Teresa Quirós、Rahul Mondal、Diego J. Cárdenas、Cristina Nevado
DOI:10.1021/jacs.9b02973
日期:2019.9.4
bond. The role of the reductant was also investigated in depth, suggesting that a one-electron reduction of Ni(II) species to Ni(I) is thermodynamically favored. Further, the preferential activation of alkyl vs aryl halides by ArNi(I) complexes as well as the high affinity of ArNi(II) for secondary over tertiary C-centered radicals explains the lack of undesired homo- and direct coupling products (Ar-Ar
没有导向或活化基团的烯烃在还原条件下用两个亲电碳源进行了双碳官能化。通过将 Ni 催化剂与作为牺牲还原剂的 TDAE 结合,在各种无偏 π 系统中同时形成一个 C(sp3)-C(sp3) 和一个 C(sp3)-C(sp2) 键,并具有极高的选择性。控制实验和计算研究揭示了基于自由基的机制的可行性,该机制涉及两个相互连接的 Ni(I)/Ni(III) 过程,并证明了 Ni(I) 物种(Ni(I)I 与 PhNi( I)) 以减少 C(sp3)-I 键。还深入研究了还原剂的作用,表明 Ni(II) 物质单电子还原为 Ni(I) 在热力学上是有利的。更多,