[RuCl2(DMSO)4] in the presence of N-benzylated 1,3,5-triaza-7-phosphaadamantane efficiently catalyzed the hydration of glycosyl cyanides to the corresponding formamide derivatives in water or water–N-methylpyrrolidone solvent mixtures at 105 °C. O-Acetyl, O-benzoyl, and O-benzyl protecting groups, anomeric bromide and azide substituents as well as double bonds were shown to be compatible with these