Cooperative NHC and Photoredox-Catalyzed Radical Azidoacylation of Alkenes to β-Amino Ketones.

The construction of azido-functionalized molecules is a common step in synthesizing nitrogen-based scaffolds of natural products and pharmaceutical compounds. Herein, we report a three-component radical azidoacylation of alkenes through cooperative N-heterocyclic carbene (NHC) and photoredox catalysis. This approach involves single-electron transfer (SET) oxidation of trimethylsilyl azide (TMSN3), followed by radical addition and subsequent coupling between a ketyl radical and a C-centered radical. Manipulation of the azido group yields a series of β-amino ketones. Mechanistic studies support a radical pathway for this reaction, and a plausible mechanism for the organocatalytic transformation is proposed.