Selective Oxidation of D‐Glucose: Chiral Intermediates for Industrial Utilization

Abstract

AbstractD‐Glucose (“dextrose”) is a building unit of starch, cellulose, sucrose and lactose. For technical and economical reasons D‐glucose is produced on large industrial scale by enzymatic hydrolysis of starch. Main use is for nutrition, as feedstock for sorbitol and HFCS (high fructose corn syrup) and as carbon source for industrial fermentations. For broader industrial use of D‐glucose, problems of selectivity, pH‐ and temperature instability and insolubility in organic solvents have to be overcome. Selective chemical and biotechnical transformations, preferably in water, are necessary and favourable intrinsic properties like biodegradability, biocompatibility and chirality have to be exploited.This paper will review/preview existing knowledge and experience on possibilities to oxidise selectivity the different hydroxyl functions at positions C1 to C6 of unprotected D‐glucopyranose in water as solvent, using biotechnical catalysts (microbial cells, enzymes) or heterogenous chemical catalysts.Transformations to the following oxidised D‐glucose derivatives will be covered.Glucosone (2‐keto‐D‐glucose), 6‐aldehydo‐D‐glucose, D‐gluconic‐acid, D‐glucuronic acid, 2‐keto‐L‐gulonic acid, D‐glucaric acid, 2‐keto‐D‐gluconic acid, 5‐keto‐D‐gluconic acid, 2,5‐diketo‐D‐gluconic acid, L‐ascorbic acid (Vitamin C) and koji acid.Some of these products are already produced on industrial scale, others show interesting potential to be used as intermediates for different industries and applications areas.