A pathway from biomass to platform chemicals Raines, R. T.; Binder, J. B. J. Am. Chem. Soc. 2009, 131, 1979-1985
Ionic Liquids + Metal Catalysts Ionic liquids are low melting organic salts (<100 0 C) that potentially comprise wide application due to their fascinating properties and have emerged as promising “green” replacement for volatile organic solvents. Like the conventional salts, ionic liquids are mainly composed of ions which are positively and negatively charge. The most attractive properties of ILs are their chemical and thermal stability, non-flammability, and negligible vapour pressure.
Typical cations and anions used in ionic liquids
HMF yields in different ionic liquids Hu, S.; Zhang, Z.; Song, J.; Zhou, Y.; Han, B.; Dalton Trans 2010, 39, 4080- 4089
Sulphate-based ionic liquids FructoseHMF Levulinic Acid Formic Acid x
Ionic Liquid Catalyst Temp. ( o C) HMF Yields (%) 3 hours HMF Yields (%) 24 hours [bmim]HSO 4 No catalyst + (15%) water 80 1144 [bmim]HSO 4 No catalyst 80 2741 [bmim]HSO 4 CrCl 3 ∙ 6H 2 O + (15%) water 80 6585 FructoseHMF
Ionic Liquid Catalyst Temp. ( o C) HMF Yields (%) 1 hours HMF Yields (%) 3 hours [bmim]HSO 4 CrCl 3 ∙ 6H 2 O1008796 [bmim]HSO 4 No catalyst 10069 [bmim]HSO 4 CrCl 3 ∙ 6H 2 O1208789 [bmim]HSO 4 No catalyst 1207178 High Temperatures
Conclusion Synthesis of RTILs (room temperature ionic liquids). High HMF yields without any side products. Around 45 % HMF yield without the use of catalyst. One of the highest (96%) HMF yields in the literature. High reaction rate.