Heteroannulation of N‑Fluoro‑N‑alkylsulfonamides with Terminal Alkynes via Remote C(sp3)–H Functionalization

A copper-catalyzed divergent annulation of N-fluoro-N-alkylsulfonamides with terminal alkynes enabled by remote C­(sp3)–H functionalization for producing 2,3-dihydro-1H-pyrroles and 1,2,3,4-tetrahydropyridines is reported. Using a terminal alkyne to capture an amidyl radical forms a vinyl carbon-centered radical, which would sequentially undergo 1,5- or 1,6-hydrogen atom transfer (HAT) to site-selectively enable functionalization of the challenging C­(sp3)–H bonds at the β- or γ-position to the nitrogen atom in N-fluorosulfonamides, thus resulting in the N-fluorosulfonamides as three- or four-atom units to accomplish the (3 + 2) or (4 + 2) heteroannulation reactions.