In a series of our studies on the direct activation of unprotected sugars in aqueous media, 7 we found that 2-chloro-1,3-dimethylimidazolinium chloride (DMC) 8 is an excellent agent for selective activation of the anomeric hydroxy groups. The reactions proceed through a reactive intermediate formed as a result of preferential attack of the anomeric hydroxy group towards DMC, based on the fact that the pK a values of hemiacetal anomeric hydroxy groups are much lower ...
