Hydrogenation Rearrangement of Furan Compounds to Cyclopentanones Catalyzed by CoNC with In Situ-Generated Uniform Metal-Acid Pairs.

The hydrogenation rearrangement of biomass-derived furan aldehydes and ketones to cyclopentanones holds significant promise for sustainable fine chemical production, but developing efficient catalysts with low metal loading and uniform metal-Brønsted sites presents a significant challenge. Herein, we report a CoNC catalyst with in situ generated uniform metal-acid pairs, which exhibits superior activity and selectivity significantly outperforming reported non-noble and noble metal catalysts. Moreover, CoNC shows excellent cycling stability and broad substrate adaptability. Catalyst characterizations, kinetic and isotopic labeling studies reveal that CoNC can efficiently dissociate H2 to form H+-N-Co-H-, and easily adsorb and activate H2O for OH- exchange to form H+-N-Co-OH-, producing abundant Brønsted acid sites that then generate uniform metal-acid pairs. The H2 activation on the Co site enables the furfural hydrogenation to furfuryl alcohol, and the in situ generated acid sites catalyze the subsequent ring-opening rearrangement. Moreover, the metal-acid pairs effectively suppress undesired side reactions such as over-hydrogenation and polymerization. This work provides a new class of metal-acid bifunctional catalyst and expands the application of M-NC catalysts.