Efficient Metal-Free Catalytic Reduction of Nitro to Amine Over Carbon Sheets Doped with Nitrogen

A highly efficient nitrogen-doped carbon sheet-like material (NCS) is developed via simple pyrolysis of β-cyclodextrin and urea at different temperatures. The effect of the pyrolysis temperature (500–800 °C) on the nitrogen species present in the catalysts is thoroughly studied. These nitrogen species formed by the pyrolysis are proven to be the active sites for the chemical conversion. These catalysts containing a significant amount of nitrogen with a high degree of defects display excellent catalytic activity towards the reduction of nitro-compounds. The effect of solvents, reaction time, and temperature in nitrobenzene reduction reaction is also studied. This protocol can be easily utilized industrially due to its several excellent features such as short reaction time, use of green solvent, column chromatography free, and applicable to the gram scale. Besides, after the reaction, the NCS catalyst can be easily recovered and reused up to five runs without significant loss on its catalytic activity. A facile and environmentally friendly method for the synthesis of metal-free NCS and their application in nitro reduction is reported.