Reductive Amination of 5-Hydroxymethyl-2-furaldehyde Over Beta Zeolite-Supported Ruthenium Catalyst

Beta-zeolite supported ruthenium catalysts for reductive amination of 5-hydroxymethyl-2-furaldehyde (HMF) with an aqueous solution of ammonia (NH₃ aq.) and molecular hydrogen (H₂) are examined to synthesize the corresponding primary amine of 5-aminomethyl-2-furylmethanol (FAA). Various SiO₂/Al₂O₃ (Si/2Al) ratios of the beta-zeolite support were used to prepare the Ru-based catalysts. It was observed that the Si/2Al ratio was contributed to the catalytic activity, and the Si/2Al?=?150 of beta-zeolite was found to be the most active for Ru catalyzed reductive amination of HMF, affording ca. 70% yield. Characterization techniques were taken to analysis the factors that influence the reactivity of catalysts, and which revealed that not only the ruthenium nanoparticle size but also the ratio of RuO₂ against metallic Ru species were crucial factors for the reactivity of reductive amination of HMF to FAA.

Graphical Abstract