Transition metal-free N-arylation of secondary amides through iodonium salts as aryne precursors.

By using a diaryliodonium salt as a benzyne precursor, a transition metal-free approach for N-arylation of secondary amides is developed. This novel benzyne precursor, which can be prepared easily by a one step process from an aryl iodide, shows different reactivities with previous benzyne precursors in the N-arylation reaction. Mechanistic studies confirm the involvement of benzyne species (generated in situ from the diaryliodonium salts) as key intermediates.