Copper-Catalyzed Alkynylation/Annulation Cascades Of N-Allyl Ynamides: Regioselective Access To Medium-Sized N-Heterocycles

A synthetic strategy based on sequential application of aza-Claisen rearrangement, C-H functionalization, C-N coupling and cyclization as key steps has been developed for the synthesis of various medium-sized N-heterocycles of pharmaceutical relevance. This efficient new method exhibits a broad scope and provides a highly efficient synthesis of N-heterocycles of different ring sizes (6-, 7-, 8-, and 9-membered rings) in moderate to good yields.