Iron-Catalyzed Radical Decarboxylative Oxyalkylation of Terminal Alkynes with Alkyl Peroxides.

An iron-catalyzed oxyalkylation of alkynes with alkyl peroxides as the alkylating reagents has been investigated. Alkyl peroxides are readily available from aliphatic acids and serve simultaneously as the alkylating reagents and internal oxidants. Primary, secondary, and tertiary alkyl groups of aliphatic acids were readily incorporated into C-C triple bonds and diverse α-alkylated ketones were synthesized. Mechanism studies revealed that this reaction involves highly reactive alkyl free radicals. A unique equilibrium between lauric acid and water catalyzed by the iron(III) catalyst was observed.