Rh(III)-Catalyzed Direct Access to 2,3-Substituted β-N-Glycosyl Indoles Through C-H Activation/annulation Coupling of β-N-Aryl Glycosides with Substituted Internal Alkynes

An efficient and selective C-H activation/annulation of readily available β-N-aryl glycosides with various alkynes has been established. Using [Cp*RhCl2]2 as a catalyst and AgSbF6 in DCE, this protocol proved to be general to prepare a variety of 2,3-substituted N-glycosyl indoles in good yields with exclusive β-selectivity.