Photo‐ and Electrochemical Cobalt Catalysed Hydrogen Atom Transfer for the Hydrofunctionalisation of Alkenes

Abstract Catalytic hydrogen atom transfer from metal‐hydrides to alkenes allows feedstock olefins to be used as alkyl radical precursors. The chemoselectivity of this process makes it an attractive synthetic tool and as such it has been regularly used in synthesis of complex molecules. However, onwards reactivity is limited by compatibility with the conditions which form the key metal‐hydride species. Now, through the merger with photocatalysis or electrochemistry, milder methods are emerging which can unlock entirely new reactivity and offer perspectives on expanding these methods in unprecedented directions. This review outlines the most recent developments in electro‐ and photochemical cobalt catalysed methods and offers suggestions on the future outlook.