Single-Electron Palladium Catalysis Enables Tandem Amidyl-Radical Cyclization/Radical Heck-Type Coupling to Allylated γ-Lactams.

An efficient tandem amidyl-radical cyclization/alkyl radical Heck reaction for the construction of allylated γ-lactams has been developed under visible-light-induced palladium catalysis. The reaction proceeds via an amidyl radical/Pd(I) hybrid species generated through photoexcited Pd(0)-mediated N-O bond cleavage of N-acyloxyamides, followed by intramolecular cyclization to form an alkyl-Pd(I) intermediate. This intermediate subsequently undergoes an intermolecular alkyl radical Heck reaction with vinyl arenes, furnishing N-alkyl allylated γ-lactams bearing diverse functional groups under mild conditions. Furthermore, successful late-stage functionalization of bioactive molecules and downstream transformations of the products underscore the utility of this method.