Enantioselective electrochemical cobalt-catalyzed aryl C–H activation reactions
Tristan von Münchow, Suman Dana, Yang Xu, Binbin Yuan, Lutz Ackermann
Abstract
Enantioselective redox transformations typically rely on costly transition metals as catalysts and often stoichiometric amounts of chemical redox agents as well. Electrocatalysis represents a more sustainable alternative, in particular through the use of the hydrogen evolution reaction (HER) in place of a chemical oxidant. In this work, we describe strategies for HER-coupled enantioselective aryl carbon-hydrogen bond (C-H) activation reactions using cobalt in place of a precious metal catalyst for the asymmetric oxidation. Thus, highly enantioselective carbon-hydrogen and nitrogen-hydrogen (C-H and N-H) annulations of carboxylic amides were achieved, which gave access to point and axially chiral compounds. Furthermore, the cobalt-mediated electrocatalysis enabled the preparation of various phosphorus (P)-stereogenic compounds by selective desymmetrization through dehydrogenative C-H activation reactions.