Synthesis of Tetrahydro-indolones through Rh(III)-Catalyzed 3 + 2 Annulation of Enaminones with Iodonium Ylides

An unprecedented protocol for a Rh(III)-catalyzed 3 + 2 annulation from simple and readily available enaminones and iodonium ylides has been developed. The novel strategy allows for access to a new class of structurally diverse tetrahydro-indolones with high efficiency and a broad substrate scope. In addition, this transformation represents the first example of the selective Rh(III)-catalyzed alkenyl C-H bond functionalization and annulation of enaminones. Finally, the potential applications of this protocol are demonstrated through gram-scale reaction and late-stage modification.