Synthesis of Phenolic Glycosides: Glycosylation of Sugar Lactols with Aryl Bromides via Dual Photoredox/Ni Catalysis.

Multifarious sugar lactols were efficiently transformed into the corresponding phenolic glycosides by treating with aryl bromides in acetonitrile with Ir[dF(CF3)-ppy](2) (dtbbpy)(PF6) as a photo catalyst under visible light irradiation. Both pyranoses and furanoses or even disaccharide could all suffer this glycosylation protocol under mild reaction conditions. A variety of phenyl glycosides can be produced in moderate to good yields (up to 93% yield), and a gram scale process of this protocol was also well-established.