An electrochemical synthesis of methyl alpha-isomaltoside.

A novel approach has been developed for the synthesis of methyl alpha-isomaltoside (10), comprising, as the first step, electrochemical conversion of the hydroxyl groups of methyl alpha-D-glucopyranoside into the corresponding anions. The anions subsequently react with tetra-O-acetyl-alpha-D-glucopyranosyl bromide to give methyl 2',3',4',6'-tetra-O-acetyl-alpha-isomaltoside (8) as the main product, O-deacetylation of which affords 10. The glycosidation proceeds under complete stereochemical control.