One-pot synthesis of 5-hydroxymethylfurfural: a significant biomass conversion over tin-promoted vanadium phosphate (Sn-VPO) catalyst

There are very few heterogeneous catalysts which have been used for the conversion of carbohydrates to fine chemicals. Herein we describe a catalytic protocol for the synthesis of 5-hydroxymethylfurfural (HMF) from glucose over a Sn-VPO catalyst. The reaction proceeds through two steps involving the isomerization of glucose to fructose and the dehydration of fructose to HMF. The catalysts were unambiguously characterized by various spectral techniques. The presence of both Lewis and Bronsted acid sites in Sn-VPO plays a crucial role in this conversion. The former acid isomerizes glucose to fructose and the latter dehydrates the fructose to HMF. The reaction has been studied by varying various reaction parameters. Under optimum conditions the 20 wt% Sn-VPO exhibits excellent results (73.79% yield). The catalyst can easily be recovered by filtration and reused several times without any appreciable change to its catalytic activity.