Electrochemical Glycosylation as an Enabling Tool for the Stereoselective Synthesis of Cyclic Oligosaccharides

Electrochemical glycosylation of a linear oligosaccharide with a protecting‐group‐free primary hydroxyl group afforded cyclic oligo‐saccharides, up to hexasaccharides, in high yields. Precursors of the cyclic oligosaccharides were prepared by automated electro‐chemical assembly‐a method for the automated electrochemical solution‐phase synthesis of oligosaccharides. We demonstrated that electrochemical glycosylation is useful not only for intermolecular glycosylation but also for intramolecular glycosylation to synthesize cyclic oligosaccharides.