Zirconium Phosphate Catalyzed Transformations of Biomass- Derived Furfural to Renewable Chemicals

Abstract

This study deals with the development of an economical, ZrPO4 mediated, one-step catalytic transformation of biomass-derived furfural into synthetic intermediates that have the capability to replace the conventional petrochemical-derived synthetic building blocks. ZrPO4 is prepared via a highly energy-efficient process at ambient temperature in the eco-friendly ethanol medium. ZrPO4 exhibits an excellent activity in the transformation of furfural into furfuryl alcohol via the eco-friendly, safe, alcohol mediated transfer hydrogenation protocol. Furthermore, furfural is also efficiently converted into furfural-derived dihydropyrimidinone and 2- (furan-2-ylmethylene)malononitrile via multicomponent Biginelli and Knoevenagel condensation reactions, respectively. Moreover, other structurally homologous biomass-derived reactants such as 5-hydroxymethyl furfural and 2,5-diformyl furan are also compared under the optimized reaction conditions along with conventional petrochemical-derived reactants such as benzaldehyde and 1-heptenal. The high activity of ZrPO4 is correlated with the acidity/basicity, pyridine FT-IR measurements, and reactant adsorption experiments. The catalyst exhibits no significant change in the activity even after five recycles. A non-noble, metal catalyzed, economical, and sustainable process for furfuryl alcohol production will certainly motivate chemists and researchers. One simple catalyst affording three functional renewable synthetic intermediates from furfural will attract a significant amount of attention of catalysis researchers and industrialists.