Polyaniline-Grafted VO(acac)2: An Effective Catalyst for the Synthesis of 2,5-Diformylfuran from 5-Hydroxymethylfurfural and Fructose

Graphical Take baby steps: Polyaniline-grafted vanadyl acetylacetonate shows high catalytic activity for the oxidation of 5-hydroxymethylfurfural (HMF) under atmospheric oxygen pressure. A high HMF conversion of 99 % and a 2,5-diformylfuran (DFF) yield of 86 % are obtained after 12 h. More importantly, the synthesis of DFF directly from fructose is also realized with two binary catalysts: Amberlyst-15 and polyaniline–vanadyl acetylacetonate. Herein, polyaniline-grafted vanadyl acetylacetonate [VO(acac) 2 ] was prepared and used as an effective catalyst for the oxidation of 5-hydroxymethylfurfural (HMF) under atmospheric oxygen pressure. A high HMF conversion of 99.2 % was obtained after 12 h at 110 °C, and 2,5-diformylfuran (DFF) was obtained in 86.2 % yield. More importantly, the one-pot conversion of fructose into DFF was also realized with two binary catalysts: Amberlyst-15 and polyaniline–VO(acac) 2 . Amberlyst-15 was used for the acid-catalyzed dehydration of fructose into HMF, followed by the in situ oxidation of HMF catalyzed by polyaniline–VO(acac) 2 . DFF could be obtained in a yield of 42.1 % from fructose by using the one-pot reaction, whereas two consecutive steps gave a higher DFF yield of 71.1 %. Owing to the facile catalyst preparation and low cost, this method showed a promising potential for the synthesis of DFF from abundant carbohydrates.