Ni-Catalyzed Electrochemical Carbonylative Ketone Synthesis Employing a Radical Sorting Strategy.

The construction of ketones with bulky units is a long-standing challenge for established nucleophilic addition or transition-metal-catalyzed cross coupling. In this work, a different route is reported to build bulky ketones ab initio that exploits the radical sorting effect in three-component cross coupling with electrolytic Ni catalysis. The sorting effect enables the selective construction of ketones, including all possible combinations of primary, secondary, and tertiary alkyl groups. In particular, the radical sorting pathway allows for efficient CO utilization and the synthesis of 13C-labeled ketones with a minimum amount of 13CO. In addition, square wave voltammetry was adopted as a quick tool to identify the catalyst driving both electron transfer and bond formation.