Intramolecular metal-catalyzed amination of pseudo-anomeric C–H bonds

Intramolecular metal-catalyzed amination of a pseudo-anomeric C–H bond in a C-glycoside is reported. Treatment of α,β-C-carbamoyloxymethyl- or β-C-sulfamoyloxymethyl glycosides with Rh2(OAc)4, PhI(OAc)2, and MgO provided original spirooxazolidines or spirooxathiazolidines in reasonable yields. No correlation between ‘anomeric’ stereochemistry and insertion efficiency was found for the conversion of carbamate derivatives whereas amination reactions of the corresponding sulfamate esters were found to be strongly dependent on the anomeric configuration.