Understanding Formation and Roles of Ni(II) Aryl Amido and Ni(III) Aryl Amido Intermediates in Ni-Catalyzed Electrochemical Aryl Amination Reactions

10 November 2022, Version 1
This content is a preprint and has not undergone peer review at the time of posting.


Ni-catalyzed electrochemical aryl amination (e-amination) is an attractive, emerging approach to forging C−N bonds as it uses air-stable Ni catalysts and efficiently proceeds at room temperature. However, in-depth mechanistic understandings of this new C−N cross-coupling methodology remain underexplored. Herein, extensive experimental and computational studies were conducted to examine the mechanism of Ni-catalyzed electrochemical aryl amination reactions. The results suggest coordination of an amine to the Ni(II) catalyst occurs before the cathodic reduction and oxidative addition steps. A stable Ni(II) aryl amido intermediate is produced from the cathodic half-reaction, a critical step in controlling the selectivity between cross-coupling and undesired homo-coupling reaction pathways. In addition, redox-active bromide in the supporting electrolyte functions as a redox mediator to promote the oxidation of the stable Ni(II) aryl amido intermediate to a Ni(III) aryl amido intermediate. Subsequently, the Ni(III) aryl amido intermediate undergoes facile reductive elimination to provide a C−N cross-coupling product at room temperature. These mechanistic insights about the Ni-catalyzed aryl e-amination are valuable for understanding and developing new Ni-catalyzed aryl e-amination reactions and also other Ni-catalyzed electrosynthetic reactions such as C−C and C−O cross-couplings.


Electrochemical synthesis
Reaction mechanism
Cross-coupling reaction
Amination reaction

Supplementary materials

Supporting Information
Supporting Information contains additional experimental details and figures and tables.


Comments are not moderated before they are posted, but they can be removed by the site moderators if they are found to be in contravention of our Commenting Policy [opens in a new tab] - please read this policy before you post. Comments should be used for scholarly discussion of the content in question. You can find more information about how to use the commenting feature here [opens in a new tab] .
This site is protected by reCAPTCHA and the Google Privacy Policy [opens in a new tab] and Terms of Service [opens in a new tab] apply.