Cr-MIL-101-Encapsulated Keggin Phosphomolybdic Acid as a Catalyst for the One-Pot Synthesis of 2,5-Diformylfuran from Fructose

The conversion of fructose into 2,5-diformylfuran (DFF) is a tandem reaction that consists of the dehydration of fructose to 5-hydroxymethylfurfural (HMF) catalyzed by an acid catalyst and subsequent oxidation of HMF to DFF by a redox catalyst. Phosphomolybdic acid encapsulated in MIL-101 (PMA–MIL-101), with high Brønsted acidity and moderate redox potential, was evaluated as a promising catalyst for the one-pot synthesis of DFF directly from fructose. The results demonstrated that PMA–MIL-101 was an efficient and recyclable bifunctional catalyst for the production of DFF from fructose in DMSO; it showed high activity and selectivity towards the direct transformation of fructose into DFF, and it could be reused. A satisfactory DFF yield of 75.1 % was obtained over 2 PMA–MIL-101 in a one-pot, one-step reaction under optimal reaction conditions.