Cobalt-Catalyzed Electrochemical Amination of Arenes

Cobalt-Catalyzed Electrochemical Amination of Arenes

Author: ChemistryViews.org

C–H activation reactions are useful synthetic tools to introduce functional groups. They can be catalyzed using transition metals, commonly noble metals. Cheaper, more abundant elements such as cobalt can be a good alternative to the expensive noble metals. However, cobalt-catalyzed reactions such as alkoxylations, aminations, and arylations need external oxidants, which can cause the formation of byproducts.

Aiwen Lei and colleagues, Wuhan University, China, have developed an electrochemical, oxidant-free, cobalt-catalyzed C–H amination of arenes. In this approach, the anodic oxidation replaces chemical oxidants. The team combined a variety of arene substrates featuring a carboxamide directing group with a range of alkylamines using Co(OAc)2·4 H2O as a catalyst, sodium pivalate as a base, and acetonitrile as a solvent under constant-current electrolysis in a divided cell.

The reaction tolerates a variety of functional groups, proceeds in moderate to good yields, and can be used on a gram scale. It needs no external oxidant and lower temperatures than previously developed cobalt-catalyzed C–H functionalizations. According to the researchers, these features are promising for industrial use.


 

Leave a Reply

Your email address will not be published.