Diverse Synthesis of C‑Glycosides by Stereoselective Ni-Catalyzed Carboboration of Glycals

C-Glycosides are important structures that are common\nto natural\nproducts and pharmaceutical agents. Established methods for their\nsynthesis involve the reaction of an activated anomeric carbon. In\nthis study, we report a conceptually new approach that involves the\nstereoselective Ni-catalyzed carboboration of glycals. In these reactions,\nnot only is a C–C bond formed at the anomeric carbon, but a\nsynthetically useful C–B bond is also installed. Upon C–B\noxidation, differentially protected C-glycosides to be formed. In\naddition, stereospecific manipulation of the C–B bond leads\nto diverse C-glycosides. Finally, we report the application of this\nmethod in the synthesis of established C-glycosides, such as C-glycosyl\namino acids, as well as a strategy to make all possible diastereomers\nat C1 and C2.