Intermolecular Radical Addition to Carbonyls Enabled by Visible Light Photoredox Initiated Hole Catalysis

Herein, we present
a novel strategy for the utilization of simple
carbonyl compounds, aldehydes and ketones, as intermolecular radical
acceptors. The reaction is enabled by visible light photoredox initiated
hole catalysis and the in situ Brønsted acid
activation of the carbonyl compound. This regioselective alkyl radical
addition reaction does not require metals, ligands or additives and
proceeds with a high degree of atom economy under mild conditions.
The proposed mechanism is supported by both experimental and theoretical
studies.