CeCl3·7H2O: a novel reagent for the synthesis of 2-deoxysugars from d-glycals

d-Glycals react smoothly with a variety of alcohols in a highly stereoselective manner in the presence of the CeCl3·7H2O–NaI reagent system in refluxing acetonitrile under neutral conditions to afford the corresponding 2-deoxy-α-glycopyranosides in high yields. In the absence of NaI, the glycals undergo Ferrier rearrangement under the influence of CeCl3·7H2O in refluxing acetonitrile to afford the corresponding 2,3-unsaturated hexopyranosides in good yields.