Merging N‐Heterocyclic Carbene Catalysis and Single Electron Transfer: A New Strategy for Asymmetric Transformations

Radical chemistry meets NHCs : NHC catalysis and single electron oxidants have been merged in several transformations, allowing the synthesis of useful β‐hydroxy esters, cyclopentanones, and spirocyclic γ‐lactones in a highly stereoselective manner. The key step is the oxidation of the NHC homoenolate equivalent to a radical species via a single‐electron transfer process (see scheme).