Electrochemical C−O Bond Formation: Facile Access to Aromatic Lactones

An efficient and robust methodology based on electrochemical techniques for the direct synthesis of aromatic lactones through dehydrogenative C−O cyclization is described. This new and useful electrochemical reaction can tolerate a variety of functional groups, and is scalable to 100 g under mild conditions. Remarkably, heterocycle‐containing substrates can be employed, thus expanding the scope of radical C−O cyclization reactions. Electric tones: An electrochemical method was developed for the facile synthesis of aromatic lactones. These mild, scalable, and atom‐economical reactions feature good yields, broad substrate scope (31 examples), and good functional‐group tolerance.