HFIP‐Triggered Reduction Radical Coupling of Enamides with Alkynes Towards β‐Keto Alkylamides via H‐Bonding Electron Transfer

Abstract This study presents metal‐free protocols for the reduction radical coupling of enamides with diverse alkynes, triggered by 1,1,1,3,3,3‐Hexafluoro‐2‐propanol (HFIP), enabling access to β‐keto alkylamides. The established approach demonstrates remarkable efficiency, facile gram‐scale synthesis, and outstanding functional group tolerance. Mechanistic investigations have revealed that the radical reaction is initiated through H‐bonding electron transfer (H b ‐ET) between enamides and HFIP promoted by acids. Notably, the introduction of H b ‐ET protocols for generating radicals represents a highly promising approach in the field of radical chemistry.