Heterogeneous V2O5/TiO2‑Mediated Photocatalytic Reduction of Nitro Compounds to the Corresponding Amines under Visible Light

The hydrogenation of nitro compounds to their correspondingaminesis developed using a heterogeneous and recyclable catalyst (V2O5/TiO2) under irradiation of blue LED(9 W) at ambient temperature. Hydrazine hydrate is used as a reductantand ethanol is used as a solvent, facilitating green, sustainable,low-cost production. The synthesis of 32 (hetero)arylamines and theirpharmaceutically relevant molecules (five) are described. Significantfeatures of the protocol include catalyst recyclability, green solvent,ambient temperature, and gram-scale reactions. Among the other aspectsstudied are H-1-NMR-assisted reaction progress monitoring,control experiments for mechanistic studies, protocol applications,and recyclability studies. Furthermore, the developed protocol enabledwide functional group tolerance,chemo-selectivity, high yield, and low-cost, sustainable, and environmentallybenign synthesis.