Photoinduced difunctionalizations of unactivated olefins enabled by ligand-to-iron charge transfer and functional group migration strategies

The difunctionalization of olefins via a radical-mediated functional group migration (FGM) strategy can simultaneously construct two or more chemical bonds, greatly improving the synthesis efficiency of organic molecules. Herein, the 1,2-dicarbofunctionalization of unactivated olefins containing migration groups with fluoroalkyl carboxylic acids or aldehydes have been developed via a photoinduced ligand-to-iron charge transfer strategy, including 1,2-fluoroalkylacylation, fluoroalkylarylation, and acylarylation. (Hetero)aryl, aromatic and aliphatic acyl groups can serve as suitable migration groups, and both aromatic and aliphatic aldehyde substrates can participate in the 1,2-acylarylation as carbon-centered radical precursors. Structurally diverse fluorine-containing alkyl, acyl and (hetero) aryl groups can be introduced into unactivated olefins through this synthetic protocol with excellent site-selectivity. Photoinduced decarboxylation or a hydrogen atom transfer process mediated by Fe(iii)-carboxylate complexes or Fe(iii)-chlorine complexes, as well as functional group migration, are the core processes of this protocol. The practicality of this method has been demonstrated by a gram-scale reaction and the derivatization of drug molecules such as ibuprofen, camphor, and gemfibrozil.