Ligand-Free Pd-Catalyzed Domino Synthesis of Carbazoles via Dehydrogenative Aromatization/C(sp2)-C(sp2) Coupling Sequence

A palladium-catalyzed domino reaction via a dehydrogenative aromatization and a dual C(sp(2))-H functionalization process for one-pot synthesis of carbazoles under ligand-free conditions has been developed. On the basis of the catalytic system, carbazoles can be synthesized in moderate to good yields from facile arylamines and cyclic ketones, which presents straightforward and practical C(sp(2))-C(sp(2)) bond formation.