Enantioselective Cyanation of Benzylic C-H Bonds via Copper-Catalyzed Radical Delay

C-H bond functionalization refers to transformations that introduce functional group directly via the cleavage of C-H bond, which shows excellent step- and atom-economy. A recent breakthrough was achieved by the Guosheng Liu group in collaboration with Shannon S. Stahl group from University of Wisconsin-Madison. They discovered a new strategy to achieve Cu-catalyzed enantioselective cyanation of benzylic C-H bonds via a "Radical Relay Process". The present copper-catalyzed method provides a remarkably chemo-, regio- and enantioselectivity to afford optical organonitriles efficiently under mild reaction conditions.