Iridium-catalyzed, ligand-controlled directed alkynylation and alkenylation of arenes with terminal alkynes

We report iridium-catalyzed C-C formation between benzamides and terminal alkynes. With the choice of a suitable ligand, a C-H alkynylation or alkenylation product could be obtained selectively. The directed C-H alkynylation proceeded without the need for an external oxidant, while the directed C-H alkenylation likely involves an unusual vinylidene mechanism. This divergent reactivity provides access to both alkynylation and alkenylation products from the same set of starting materials.