Chemo- and Regioselective Oxidation of Secondary Alcohols in Vicinal Diols

Oxidation of secondary hydroxyl groups in vicinal diols enables the straightforward functionalization of biomolecules and biomaterials. The resulting hydroxy ketone can for example be used to form derivatives, such as the epimeric alcohol and imines, and it may be employed for chemical probe synthesis. Regioselectivity becomes an essential factor when this strategy is applied to compounds containing multiple hydroxyl groups, such as carbohydrates. Large advances have been made in this field in the past decade, which has led to the development of novel methodologies that enable selective oxidation of secondary hydroxyl groups of 1,2-diols in complex molecules which have complementary regioselectivities. We here discuss these recent advances as well as some of the limitations. Future research should focus on addressing these issues, which will eventually lead to methods for the chemo- and regioselective oxidation of complex oligosaccharides.