Heterogeneously novel xWO3/SO42-/SnO2 catalysts to improve the direct etherification of glycerol with D-Glucose in absence of organic solvents

Abstract

We have synthesized different diastereomers of α- and β-D-glucopyranosyl glycerol without organic solvent, using 15wt% SO42-/SnO2 with different ratios of tungsten oxide and the prepared catalysts were calcined at 400 °C. The present catalytic process is a new route of a synthesis of free salt and metal for the nucleophilic addition of polyol to a monosaccharide. In this article, the catalytic performance of solid acids WO3/SO42-/SnO2 was investigated for the etherification of glycerol with D- glucose in solvent-free conditions. Under optimized conditions, up to 95.82 % yield of glycerol ethers (α- and β-D-glucopyranosyl glycerol ) was obtained. The activity results revealed the promoted catalysts WO3/SO42-/SnO2 show an excellent catalytic selectivity in the etherification of glycerol in comparison of other known catalysts. α- and β-D-glucopyranosyl glycerol synthesized are precursors of amphiphilic surfactants. The reaction progress was monitored with a gas chromatography-mass spectrometry GC-MS, after silylation reaction of the products to ease the separation and identification