Oxidation of Maltodextrins and Starch by the System Tungstate‐Hydrogen Peroxide

The potential of the aqueous system sodium tungstate‐hydrogen peroxide for glycol‐cleavage oxidation of maltodextrins, starch and trans‐1,2‐cyclohexanediol as a model compound has been evaluated. The peroxotungstate species formed in this medium effect oxidation of the glucose units via two major pathways: (i) glycol‐cleavage of the C2–C3 diol moieties in internal glucose units, followed by (undesired) hydrolysis of the ring‐opened intermediate and (ii) stepwise decarboxylation at the reducing terminal glucose unit until the glycosidic bond is reached. Both reaction types yield glucose oligomers terminated by erythronic acid at the former reducing end, which is an important fraction (up to 40%) of the oxidation product. Decomposition of hydrogen peroxide to oxygen and water is an inevitable side reaction.