An efficient approach to biomass-based tertiary amines by direct and consecutive reductive amination of furfural

Direct and consecutive reductive amination of furfural was developed with Rh 2 P catalyst for efficient synthesis of biomass-based tertiary amine. • Biomass-based tertiary amines are developed for extension of amine chemistry. • Direct and consecutive reductive amination of furfural leads to tertiary amines. • Rh 2 P selectively and efficiently promotes the reactions with wide substrate scope. • Mechanism is supported by both experimental and theoretical investigations. • Excellent stability and recyclability of catalyst during consecutive recycling. Tertiary amines, currently obtained from fossil resources by a multi-step synthetic method, are important compounds in both chemical industry and organic transformations. Herein, we demonstrated highly efficient and convenient strategy to various biomass-based tertiary amines in excellent yields (85–95%) by a direct and consecutive reductive amination of furfural with various amines in one-pot using rhodium phosphide (Rh 2 P) catalyst. Typically, biomass-based tris (2-furanylmethyl)amine in 92% yield was directly obtained from furfural and HCOONH 4 in one-step. Time-dependent reaction profiles suggested a consecutive amination/hydrogenation pathway with furfurylamine-derived Schiff base and secondary amine as successively detected intermediates. The superiority of Rh 2 P was ascribed to its excellent low-temperature hydrogenation activity, which is structurally attributed to an efficient electron-transfer from P atoms (on the P-terminated Rh 2 P) to their bonded and dissociated H atoms. This research thus highlights a powerful, elegant, and attractive approach to biomass-based tertiary amines for a sustainable extension of amine chemistry.