Selective glucose transformation by titania as a heterogeneous Lewis acid catalyst

The Lewis acidity of phosphate-immobilized anatase TiO2 (phosphate/TiO2) has been studied to develop novel environmentally benign reaction systems. Fourier transform infrared (FT-IR) measurements suggested that most Lewis acid sites on bare and phosphate/TiO2 surface function even in water. phosphate/TiO2 exhibits high catalytic performance for selective 5-(hydroxymethyl)furfural (HMF) production from glucose in THF/water (90/10 vol.%) solution. This is attributed to water-tolerant Lewis acid sites on phosphate/TiO2 that promote step-wise conversion of glucose into HMF. The catalyst was easily recovered from reaction solution by simple decantation or filtration, and can be used repeatedly without significant loss of original activity for subsequent reactions. (c) 2013 Elsevier B.V. All rights reserved.