Aryne-Enabled C-N Arylation of Anilines

Anilines are potentially high-value arylating agents, but are limited by the low reactivity of the strong C-N bond. We show that the reactive intermediate benzyne can be used to both activate anilines, and set-up an aryl transfer reaction in a single step. The reaction does not require any transition metal catalysts or stoichiometric organometallics, and establishes a metal-free route to valuable biaryl products by functionalizing the aniline C-N bond. A transition metal-free C-N arylation of easily accessible tertiary anilines enabled by bifunctional arynes is described. The reaction proceeds via a tandem nucleophilic attack of anilines to arynes, followed by a Smiles-Truce rearrangement to furnish synthetically valuable and densely substituted biaryls. This protocol was further utilized for heterocyclic scaffolds, providing access to medium size azaheterocycles via n+2 carbon insertion.+image