Reductive Amination of 5-Hydroxymethylfurfural to 2,5-Bis(aminomethyl)furan over Alumina-Supported Ni-Based Catalytic Systems

Mono- and bimetallic Ni-based catalysts were prepared by screening 6 supports and 14 secondary metals for reductive amination of 5-hydroxymethylfurfural (5-HMF) into 2,5-bis(aminomethyl)furan (BAMF), among which gamma-Al2O3 and Mn were the best candidates. By further optimization of the reaction conditions at 0.4 g catalyst loading for 0.5 g substrate of 5-HMF and 160 degrees C of reaction temperature, 10Ni/gamma-Al2O3 and 10NiMn(4 : 1)/gamma-Al2O3 achieved the highest BAMF yields of 86.3 and 82.1 %, respectively. Although the BAMF yield values were comparable with that over Raney Ni, the turnover frequencies based on the initial BAMF yield and unit weight of Ni for 10NiMn(4 : 1)/gamma-Al2O3, 10Ni/gamma-Al2O3, and Raney Ni were calculated as 0.41, 0.09, and 0.04 h(-1), respectively. X-ray diffraction, transmission electron microscopy, and X-ray photoelectron spectroscopy showed that the existence of MnOx well dispersed on the gamma-Al2O3 support and its electron transfer effect with Ni particles on the surface of the support contributed to the high efficiency and better recyclability for the five-time reused 10NiMn(4 : 1)/gamma-Al2O3 catalyst.

Automated summary

Mono- and bimetallic Ni-based catalysts were prepared for the reductive amination of 5-hydroxymethylfurfural (5-HMF) into 2,5-bis(aminomethyl)furan (BAMF) using 6 supports and 14 secondary metals. Gamma-Al2O3 and Mn were found to be the most effective supports. By optimizing the reaction conditions, the 10Ni/gamma-Al2O3 and 10NiMn(4 : 1)/gamma-Al2O3 catalysts achieved the highest BAMF yields of 86.3% and 82.1%, respectively. The presence of well-dispersed MnOx on the gamma-Al2O3 support and its electron transfer effect with Ni particles contributed to the high efficiency and recyclability of the 10NiMn(4 : 1)/gamma-Al2O3 catalyst.