Ketone-Derived Dihydroquinazolinones as Carbamoyl Radical Precursors for Photoredox Amidation of Electron-Deficient Alkenes

A visible-light photoredox strategy for the amidation of electron-deficient alkenes is disclosed, enabled by ketone-derived, carbamoyl-functionalized dihydroquinazolinones as a new class of carbamoyl radical precursors. Under mild conditions, these readily accessible proaromatic reagents undergo aromatization-promoted C-C bond cleavage to generate carbamoyl radicals, which engage in efficient conjugate addition to activated olefins, delivering diverse amide products. The protocol features a broad substrate scope, accommodating tertiary, secondary, and primary carbamoyl radicals and a wide range of electron-deficient alkenes, including sterically demanding and highly functionalized substrates. This work expands the reactivity profile of dihydroquinazolinones and provides a general, operationally simple platform for amide synthesis via C-C bond formation under visible-light photoredox catalysis.