Cu-Catalyzed Arylation/Acyl Migration Cascade Reaction of Enaminones: Access to N-Fused Polycyclic and 2,3-Disubstituted Indoles.

An efficient synthesis of N-fused polycyclic and 2,3-disubstituted indoles by copper-catalyzed direct annulation/acyl migration reaction of enaminones is reported. This strategy features cheap and low loading of the catalyst/ligand, readily available starting materials, and good functional group compatibilities. Notably, allyl-containing substrates are also tolerated, which allows the downstream derivatization toward indole alkaloids.