Ligand Redox Activity of Organonickel Radical Complexes Governed by the Geometry.
Ligand Redox Activity of Organonickel Radical Complexes Governed by the Geometry.
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DOI：
10.1021/jacs.3c07031
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发表时间：
2023-09-20
影响因子：
15
通讯作者：
Diao, Tianning
中科院分区：
文献类型：
--
作者：
Dawson, Gregory A.;Lin, Qiao;Neary, Michelle C.;Diao, Tianning
镍催化的交叉偶联反应通常采用双齿 π 受体 N 配体来促进自由基途径。本报告介绍了一系列由二齿 N-配体支持的有机镍自由基配合物的合成和表征，包括 bpy、phen 和 Pyrox，它们是催化反应中常见的被提出和观察到的中间体。通过相关类似物的比较，我们建立了控制这些镍自由基配合物电子结构的经验规则。 N-配体在四配位、方形平面镍自由基配合物中表现出氧化还原活性，从而观察到以配体为中心的自由基。相反，这些配体在负载三配位、三角平面镍自由基络合物时不表现出氧化还原活性，最好将其描述为以镍为中心的自由基。无论作用配体的性质如何，这种趋势都成立。这些结果提供了关于配位盐添加剂和溶剂通过调节配体的氧化还原活性来稳定催化反应期间镍自由基中间体的有益效果的见解。了解这些活性中间体的电子结构有助于开发和优化用于交叉偶联反应的镍催化剂。
Nickel-catalyzed cross-coupling reactions often employ bidentate π-acceptor N-ligands to facilitate radical pathways. This report presents the synthesis and characterization of a series of organonickel radical complexes supported by bidentate N-ligands, including bpy, phen, and pyrox, which are commonly proposed and observed intermediates in catalytic reactions. Through a comparison of relevant analogues, we have established an empirical rule governing the electronic structures of these nickel radical complexes. The N-ligands exhibit redox activity in four-coordinate, square-planar nickel radical complexes, leading to the observation of ligand-centered radicals. In contrast, these ligands do not display redox activity when supporting three-coordinate, trigonal planar nickel radical complexes, which are better described as nickel-centered radicals. This trend holds true irrespective of the nature of the actor ligands. These results provide insights into the beneficial effect of coordinating salt additives and solvents in stabilizing nickel radical intermediates during catalytic reactions by modulating the redox activity of the ligands. Understanding the electronic structures of these active intermediates can contribute to the development and optimization of nickel catalysts for cross-coupling reactions.
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影响因子：
37.8
作者：
Day, Craig S. S.;Renteria-Gomez, Angel;Martin, Ruben
通讯作者：
Martin, Ruben
影响因子：
15
作者：
Diccianni, Justin B.;Katigbak, Joseph;Diao, Tianning
通讯作者：
Diao, Tianning
影响因子：
8.4
作者：
Hu, Xile
通讯作者：
Hu, Xile
DOI：
10.1126/science.aaf7230
发表时间：
2017-04-14
期刊：
Science (New York, N.Y.)
影响因子：
--
作者：
Choi J;Fu GC
通讯作者：
Fu GC
影响因子：
15
作者：
Ju L;Lin Q;LiBretto NJ;Wagner CL;Hu CT;Miller JT;Diao T
通讯作者：
Diao T