Nitrogen-doped carbon materials were discovered to be active for the aerobic oxidation of 5-hydroxymethylfurfural to 2,5-diformylfuran with the assistance of nitric acid.

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In this study, nitrogen-doped carbon materials (labeled as NC-T) were easily prepared by thermal treatment of the melamine−chitosan composite. NC-T catalysts demonstrated good activity toward the reduction of nitro compounds by using hydrazine hydrate (N 2 H 4 •H 2 O) as the reductant. The activity of NC-T enhanced with the rise of the pyrolysis temperature because of the enhanced ratio of graphitic-type nitrogen, which might be the active sites for the reduction of nitro compounds. NC-950 showed high activity for the selective reduction of nitro compounds in hexane to produce amines at yields from 87.5 to 100% at 90 °C using 2 equiv of N 2 H 4 •H 2 O. The NC-950 catalyst demonstrated comparable or even higher catalytic activity in comparison with the reported metal catalysts. The hydrogenation of nitro compounds with N 2 H 4 •H 2 O proceeded via the direct way involving hydroxylamine as the reaction intermediate.

An efficient method was developed for the synthesis of primary amines either from the hydrogenation of nitriles or reductive amination of carbonyl compounds. The reactions were catalyzed by nitrogen‐doped mesoporous carbon (MC)‐supported nickel nanoparticles (abbreviated as MC/Ni). The MC/Ni catalyst demonstrated high catalytic activity for the hydrogenation of nitriles into primary amines in high yields (81.9–99 %) under mild reaction conditions (80 °C and 2.5 bar H2). The MC/Ni catalyst also promoted the reductive amination of carbonyl compounds for the synthesis of primary amines at 80 °C and 1 bar H2. The hydrogenation of nitriles and the reductive amination proceeded through the same intermediates for the generation of the primary amines. To the best of our knowledge, no other heterogeneous non‐noble metal catalysts have been reported for the synthesis of primary amines under mild conditions, both from the hydrogenation of nitriles and reductive amination.

Cesium-doped manganese dioxide (Cs/MnOx) was prepared by a soft template method, and was found to be active for the selective oxidation of HMF to DFF with molecular oxygen.