Photoredox‐Catalyzed Addition of Carbamoyl Radicals to Olefins: A 1,4‐Dihydropyridine Approach

Functionalization with C1‐building blocks are key synthetic methods in organic synthesis. The low reactivity of the most abundant C(1)‐molecule, carbon dioxide, makes alternative carboxylation reactions with CO(2)‐surrogates especially important. We report a photoredox‐catalyzed protocol for alkene carbamoylations. Readily accessible 4‐carboxamido‐Hantzsch esters serve as convenient starting materials that generate carbamoyl radicals upon visible light‐mediated single‐electron transfer. Addition to various alkenes proceeded with high levels of regio‐ and chemoselectivity.