Phosphorous pentoxide mediated synthesis of 5-HMF in ionic liquid at low temperature

A convenient, mild and environment-friendly dehydration reaction of fructose in ionic liquid using phosphorous pentoxide (P2O5) has been investigated. The acidic nature of P2O5 along with its hygroscopic properties has been successfully utilized to afford 81.2% yield of 5-hydroxymethylfurfural (5-HMF) at 50 °C in 60 mins. Phosphoric acid yielded remarkably less 5-HMF even at higher temperature and longer reaction times. The reaction was optimized by varying different parameters and the results indicated that no rehydration products, such as levulinic acid or formic acid, were formed.

Figure optionsDownload as PowerPoint slideHighlights
► Phosphorous pentoxide as a highly efficient catalyst for 5-HMF synthesis from fructose.
► Provides highest yield at a lower temperature of 50 °C.
► Much effective compared to its corresponding acid and other anhydrides.
► Provides better yield in [BMIM]Cl than in other solvents.