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Oxidative cyanation of aldehydes provides a promising strategy for the cyanide‐free synthesis of organic nitriles. Design of robust and cost‐effective catalysts is the key for this route. Herein, we designed a series of Se,S,N‐tri‐doped carbon nanosheets with a hierarchical porous structure (denoted as Se,S,N‐CNs‐x, x represents the pyrolysis temperature). It was found that the obtained Se,S,N‐CNs‐1000 was very selective and efficient for oxidative cyanation of various aldehydes including those containing other oxidizable groups into the corresponding nitriles using ammonia as the nitrogen resource below 100 °C. Detailed investigations revealed that the excellent performance of Se,S,N‐CNs‐1000 originated mainly from the graphitic‐N species with lower electron density and synergistic effect between the Se, S, N, and C in the catalyst. Besides, the hierarchically porous structure could also promote the reaction. Notably, the unique feature of this metal‐free catalyst is that it tolerated other oxidizable groups, and showed no activity on further reaction of the products, thereby resulting in high selectivity. As far as we know, this is the first work for the synthesis of nitriles via oxidative cyanation of aldehydes over heterogeneous metal‐free catalysts. [ABSTRACT FROM AUTHOR]

Cleavage of aromatic ether bonds is a key step for lignin valorization, and the development of novel heterogeneous catalysts with high activity is crucial. Herein, bifunctional Ru/hydroxyapatite has been prepared via ion exchange and subsequent reduction. The obtained Ru/hydroxyapatite could efficiently catalyze the cleavage of various compounds containing aromatic ether bonds via transfer hydrogenolysis without additional bases. Systematic studies indicated that the basic nature of hydroxyapatite and electron-enriched Ru sites resulted in the high activity of the catalyst. A mechanism study revealed that the direct cleavage of aromatic ether bonds was the main reaction pathway. [ABSTRACT FROM AUTHOR]