关键词: Chemoselective hydrogenation, Carbon encapsulated, Metal-organic frameworks, Nickel nanoparticles, Nitroarenes

Abstract: Replacement of precious noble metal catalysts with cost-effective, non-noble heterogeneous catalysts for chemoselective hydrogenation of nitroarenes holds tremendous promise for the clean synthesis of nitrogen-containing chemicals. Graphitic carbon layers encapsulated Ni catalysts (Ni@CN) are generated by a facile, scalable and straightforward strategy via the pyrolysis of 2,5-pyridinedicarboxylic acid coordinated Ni-MOF acting as the precursor. Physicochemical properties of the Ni@CN catalysts have been investigated by X-ray diffraction, scanning electron microscopy, transmission electron microscopy, elemental analysis and N2 adsorption-desorption analysis. The Ni@CN catalysts were found to be highly efficient in the chemoselective hydrogenation of various nitroarenes with other functional groups towards corresponding anilines under mild reaction conditions (85 °C, 1.0 MPa of H2 pressure). Based on the results of controlled tests, the catalytic activity can be attributed to the Ni NPs, while the presence of graphitic carbon layers favors the preferential adsorption of the nitro groups. The recyclability and anti-sulfur poisoning capability of Ni@CN were also investigated.

Key words: Chemoselective hydrogenation, Carbon encapsulated, Metal-organic frameworks, Nickel nanoparticles, Nitroarenes