Electrochemical Glycosylation via Halogen-Atom-Transfer for -Glycoside Assembly.

Glycosyl donor activation emerged as an enabling technology for anomeric functionalization, but aimed primarily at -glycosylation. In contrast, we herein disclose mechanistically distinct electrochemical glycosyl bromide donor activations via halogen-atom transfer and anomeric -glycosylation. The anomeric radical addition to alkenes led to -alkyl glycoside synthesis under precious metal-free reaction conditions from readily available glycosyl bromides. The robustness of our e-XAT strategy was further mirrored by -aryl and -acyl glycosides assembly through nickela-electrocatalysis. Our approach provides an orthogonal strategy for glycosyl donor activation with expedient scope, hence representing a general method for direct -glycosides assembly.