Decarboxylative Borylation of Stabilized and Activated Carbon Radicals

Abstract Redox‐active esters (RAEs) as active radical precursors have been extensively studied for C−B bond formations. However, the analogous transformations of stabilized radicals from the corresponding acid precursors remain challenging owing to the strong preference towards single‐electron oxidation to the stable carbocations. This work describes a general strategy for rapid access to various aliphatic and aromatic boronic esters by mild photoinduced decarboxylative borylation. Both aryl and alkyl radicals could be generated from the leaving group‐assisted N‐hydroxybenzimidoyl chloride esters, even α‐CF 3 substituted substrates could be activated for further elaboration.