Catalyst-Controlled, Site-Selective Functionalization of Levoglucosan Analogues Mediated by Chiral Zinc Diamine Complexes

In this work, we developed a site-selective functionalization of levoglucosan analogues. This strategy used simple zinc diamine complexes for regioselective functionalization at O2 or O4. Successful transformations of monotosyl analogues allowed the preparation of useful intermediates in carbohydrate chemistry, such as four protected Černý epoxides and three protected amino sugars. This unique method represents a rare use of zinc for the desymmetrization of 1,3-diols.