Oxidation of Enones for Regioselective [3+2] Cycloaddition through γ‐Enone Radical Intermediates

Herein, an oxidization reaction of enones with a CuII complex that leads to a new type of regioselective [3+2] cycloaddition is reported. Highly functionalized cyclopentenes and spirocyclic compounds are obtained in moderate‐to‐good yields. This cycloaddition reaction occurred through the formation of γ‐enone radicals, providing a rarely explored reactivity pattern for enones. Going radical: The oxidization of enones with a CuII complex leads to a regioselective [3+2] cycloaddition reaction to furnish highly functionalized cyclopentenes and spirocyclic compounds in moderate‐to‐good yields, disclosing a new type of [3+2] cycloaddition. This cycloaddition reaction takes place through the formation of γ‐enone radicals, providing a rarely explored reactivity pattern for enones.