Synthesis of 1,4‐Dicarbonyl Compounds via Visible‐Light‐Induced Decarboxylative Radical Cascade Reactions

Abstract We herein report a method for the synthesis of 1,4‐dicarbonyl compounds using light‐activated electron donor‐acceptor (EDA) complexes. This multi‐component reaction involves the photoactivation of EDA complexes formed by carboxylic acid derivatives, triphenylphosphine, and sodium iodide, resulting in single‐electron reduction. The subsequent decarboxylation fragmentation leads to the formation of nucleophilic alkyl free radicals, which can undergo sequential radical coupling reactions with electron‐deficient and electron‐rich olefins. This method has been successfully applied to various aliphatic carboxylic acid derivatives, including tertiary, secondary, and primary ones, as well as multiple types of electron‐deficient olefins and enol silyl ethers. The entire process is conducted under mild conditions, indicating its potential for the synthesis of valuable synthetic compounds.