Annulation Cascades of N-Allyl- N-((2-bromoaryl)ethynyl)amides Involving C-H Functionalization.

An annulation cascades of N-allyl- N-((2-bromoaryl)ethynyl)amides with terminal alkynes or 1,3-dicarbonyls involving C-H functionalization for producing 2,3-functionalized indoles has been first developed by means of Cu catalysis. The method is enabled by the formation of the ketenimine intermediates to deliver 2,3-disubstituted indoles through a sequence of aza-Claisen rearrangement, C-H functionalization, Ullmann C-N coupling, and cyclization.