An Organic Intermolecular Dehydrogenative Annulation Reaction.

The discovery of a direct method for the synthesis of three-ring heterocyclic carbazoles from unactivated arenes and anilides by a metal-free (organic) intermolecular dehydrogenative annulation reaction under ambient laboratory conditions is reported. Iodine(III) was used as the sole reagent either stoichiometrically from inexpensive phenyliodine diacetate or organocatalytically by in situ generation from PhI-mCPBA. In a single step, three C(sp2)-H bonds and one N(sp3)-H bond are functionalized from two different arenes for tandem C-C and C-N bond formation reactions.