Photocatalytic Alkynyl-Carbamoylation of Alkenes via Radical-Polar Crossover

Carbamoyl radical-initiated alkene difunctionalization has emerged as an efficient strategy for assembling structurally complex amide derivatives, although this field remains underdeveloped. Compared to well-established transformations relying on carbanions or carbon radicals, a method utilizing a carbon cation for the electrophilic addition pathway has not yet been realized, primarily because the carbocation intermediate is susceptible to β-H deprotonation to form an α,β-unsaturated amide. Employing potassium alkynyltrifluoroborate as the nucleophile, we achieved the first photocatalytic carbamoyl radical-initiated alkene difunctionalization involving a carbocation pathway. This protocol features mild conditions, high chemoselectivity, and broad substrate scopes.