Silver-catalysed intermolecular benzylic-selective C–H amidation via nitrene transfer

Abstract

Transition metal-catalysed C–H functionalisation is a powerful strategy to upgrade simple hydrocarbons to versatile synthetic building blocks and is a useful tool for the late-stage functionalisation of complex molecules. In this study, we report an intermolecular, non-directed amidation of benzylic C–H bonds via a nitrene transfer pathway. This operationally simple method uses inexpensive silver-based catalysts, only a small excess of substrate and displays broad substrate scope that includes arenes, biaryls, heteroarenes, and complex molecules. Changes to the AgNTf₂ : tert-butylterpyridine ligand ratio furnish dimeric or trimeric Ag complexes as the proposed active catalysts; these show differing reactivity and selectivity dependent on the nature of the substrate's benzylic C–H bond.