A photo- and cobalt-catalyzed highly selective and divergent hydrofunctionalization of 1,3-dienes with phenols

An applicable cobalt-hydride-mediated selective, divergent hydroetherification and sequential hydroetherification/hydroarylation of 1,3-dienes with simple phenol feedstocks under a photoredox and cobalt catalytic system have been developed. A variety of allyl aryl ethers and value-added chroman derivatives can be obtained in good to excellent yields and stereoselectivity. This method not only obviates the need for extra hydrosilanes and stoichiometric oxidants, thereby offering exceedingly mild conditions for alkene hydroetherification, but also represents the first case of CoH-HAT-catalyzed sequential double hydrofunctionalization of alkenes with a sole nucleophile. The continuous and selective bond-forming catalytic system expands the applications of the cobalt-hydride MHAT reaction and provides a novel approach for the design and synthesis of heterocyclic molecules.