Chemoselective hydrogenation of functionalized nitroarenes using MOF-derived co-based catalysts

• Published in: Journal of molecular catalysis. A, Chemical Chemical, 2016-08, Vol.420, p.56-65
• Main Authors: Wang, Xi, Li, Yingwei
• Format: Article
• Language: English
• Subjects: Amines; Cobalt; Heterogeneous catalysis; Hydrogenation; Metal-organic frameworks
• ISSN: 1381-1169; 1873-314X
• DOI: 10.1016/j.molcata.2016.04.008

A novel MOF-derived metallic cobalt-based catalyst is developed for chemoselective hydrogenation of substituted nitroarenes. A broad range of substituted nitroarenes are converted to the corresponding anilines in 93–99% yields under industrially viable conditions with other reducible groups remaining intact. [Display omitted] •Co/C–N was prepared by simple pyrolysis of MOFs.•Nitroarenes are converted to anilines with other reducing groups remaining intact.•Co-N centers present in the catalyst lead to the unique chemoselectivity.•The reaction showed a first-order dependence on H2 pressure. The synthesis, characterization, and application of nitrogen-doped carbon supported Co catalysts in selective hydrogenation of nitroarenes are described. The cobalt-based catalysts are prepared by simple pyrolysis of ZIF-67, a typical MOF material, under inert atmosphere. Physicochemical properties of the Co/C–N catalysts have been investigated by X-ray diffraction, elemental analysis, atomic absorption spectroscopy, scanning electron microscopy, transmission electron microscopy, Fourier transform infrared spectroscopy, and X-ray photoelectron spectroscopy. The Co-based materials were found to be highly efficient in the chemoselective hydrogenation of nitroarenes. A broad range of substituted nitroarenes are converted to the corresponding anilines in excellent yields under industrially viable conditions with other reducing groups remaining intact. In situ ATR-IR and XPS characterizations reveal that the Co-N centers present in the catalyst favor the preferential adsorption of nitro groups, leading to this unique chemoselectivity. The kinetic parameters of 4-nitrostyrene hydrogenation over the Co/C–N catalyst were investigated.