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Metal‐catalyzed C–N cross‐coupling generally forms C−N bonds by reductive elimination from metal complexes bearing covalent C‐ and N‐ligands. We have identified a Cu‐mediated C–N cross‐coupling that uses a dative N‐ligand in the bond‐forming event, which, in contrast to conventional methods, generates reactive cationic products. Mechanistic studies suggest the process operates via transmetalation of an aryl organoboron to a CuII complex bearing neutral N‐ligands, such as nitriles or N‐heterocycles. Subsequent generation of a putative CuIII complex enables the oxidative C–N coupling to take place, delivering nitrilium intermediates and pyridinium products. The reaction is general for a range of N(sp) and N(sp2) precursors and can be applied to drug synthesis and late‐stage N‐arylation, and the limitations in the methodology are mechanistically evidenced., Cu(OTf)2 promotes the oxidative arylation of nitriles and N‐heterocycles to generate ionic products. Mechanistic studies suggest the process operates via reductive elimination from a CuIII complex bearing neutral N‐ligands to generate nitrilium and pyridinium products. The reaction is general for a range of N(sp) and N(sp2) precursors and can be applied to drug synthesis and late‐stage N‐arylation.

Control of boronic acid speciation is presented as a strategy to achieve nucleophile chemoselectivity in the Suzuki-Miyaura reaction. Combined with simultaneous control of oxidative addition and transmetalation, this enables chemoselective formation of two C-C bonds in a single operation, providing a method for the rapid preparation of highly functionalized carbogenic frameworks.