The quantification of factors that influence both rates and stereoselectivity of anomerization reactions catalyzed by SnCl4 and TiCl4 and how this has informed the synthesis of α-O-and α-S-glycolipids is discussed. The SnCl4-catalyzed anomerization reactions of β-S-and β-O- glycosides of 18 substrates followed first order equilibrium kinetics and kf+ kr values were obtained, where kf is the rate constant for the forward reaction (β→ α) and kr is the rate ...