Selective catalysis for the reductive amination of furfural toward furfurylamine by graphene-co-shelled cobalt nanoparticles

Abstract

Amines with functional groups are widely used in the manufacture of pharmaceuticals, agricultural chemicals, and polymers but most of them are still prepared through petrochemical routes. The sustainable production of amines from renewable resources, such as biomass, is thus necessary. For this reason, we developed an eco-friendly, simplified, and highly effective procedure for the preparation of a non-toxic heterogeneous catalyst based on earth-abundant metals, whose catalytic activity on the reductive amination of furfural or other derivatives (more than 24 examples) proved to be broadly available. More surprisingly, the cobalt-supported catalyst was found to be magnetically recoverable and reusable up to eight times with an excellent catalytic activity; on the other hand, the gram-scale tests catalyzed by the same catalyst exhibited the similar yield of the target products in comparison to its smaller scale, which was comparable to the commercial noble-based catalysts. Further results from a series of analytical technologies involving XRD, XPS, TEM/mapping, and in situ FTIR revealed that the structural features of the catalyst are closely in relation to its catalytic mechanisms. In simple terms, the outer graphitic shell is activated by the electronic interaction as well as the induced charge redistribution, enabling the easy substitution of the –NH₂ moiety toward functionalized and structurally diverse molecules, even under very mild industrially viable and scalable conditions. Overall, this newly developed catalyst introduces the synthesis of amines from biomass-derived platforms with satisfactory selectivity and carbon balance, providing cost-effective and sustainable access to the wide applications of reductive amination.