Visible-Light-Promoted Copper-Catalyzed Regioselective Benzylation of Pyridine N-Oxides versus Thermal Acylation Reaction with Toluene Derivatives

Copper-catalyzed visible light mediated direct C-H bond benzylation of pyridine N-oxides with toluene derivatives was accomplished by recent developments in photochemical carbon-carbon bond formation through a photo-induced bond-dissociation strategy. This visible light driven protocol has been successfully applied to a broad scope of pyridine N-oxides and toluene derivatives. Furthermore, preliminary research indicates that the acylation reaction can be carried out under thermal reaction conditions. This protocol provides easy access to 2-benzyl and 2-acyl pyridine N-oxide derivatives in the presence of a copper catalyst.