Ambient-Temperature Reductive Amination of 5-Hydroxymethylfurfural Over Al2O3-Supported Carbon-Doped Nickel Catalyst

An efficient catalytic system for the conversion of 5-hydroxymethylfurfural (HMF) into N-containing compounds over low-cost non-noble-metal catalysts is preferable, but it is challenging to reach high conversion and selectivity under mild conditions. Herein, an Al2O3-supported carbon-doped Ni catalyst was obtained via the direct pyrolysis-reduction of a mixture of Ni-3-(BTC)(2)center dot 12H(2)O and Al2O3 generating stable Ni-0 species due to the presence of carbon residue. A high yield of 96% was observed in the reductive amination of HMF into 5- hydroxymethyl furfurylamine (HMFA) with ammonia and hydrogen at ambient temperature. The catalyst was recyclable and could be applied to the ambient-temperature synthesis of HMF-based secondary/tertiary amines and other biomass-derived amines from the carbonyl compounds. The significant performance was attributable to the synergistic effect of Ni-0 species and acidic property of the support Al2O3, which promoted the selective ammonolysis of the imine intermediate while inhibiting the potential side reaction of over-hydrogenation.

Automated summary

An efficient catalytic system using a low-cost non-noble-metal catalyst was developed for the conversion of 5-hydroxymethylfurfural (HMF) into N-containing compounds. A carbon-doped Ni catalyst supported on Al2O3 was obtained via pyrolysis-reduction, and it showed high selectivity and yield in the reductive amination of HMF. The catalyst could be recycled and applied to the synthesis of biomass-derived amines at ambient temperature.