Bridging coordination chemistry and heterogeneous catalysis: Co/BIAN complexes for nitroarene hydrogenation catalysts

Transition-metal based nitrogen-doped modified carbon composites are attractive tools in the catalysis field. Their unique electronic, chemical and physic properties permit the preparation of active and recyclable catalysts which applications range from organic synthesis, pollutants remediation, electrocatalysis and energy-related transformations. An efficient way to synthetize them involve the pyrolysis of well-defined metal complexes immobilized on various supports. In this study, we present the preparation, characterization and application of seven different Co-based catalysts in which the nitrogen network is provided by the pyrolysis of Co/BIAN complexes supported on Vulcan carbon. These materials show a core-shell architecture that allows achieving excellent selectivities in the hydrogenation of various substituted nitroaromatics. Straightforward kinetic experiments allow us to correlate the catalytic activity with the amount and type of nitrogen (determined by CHN and XPS analyses) present in the materials. Finally, based on the collected whole data, a reaction mechanism that involves a heterolytic activation of the dihydrogen molecule was postulated.