Superparamagnetic core-shell metal-organic framework (Fe3O4@Ni-Co-BTC NPs): an efficient and magnetically retrievable nanostructured catalyst for the reduction of nitro compounds to amines

Herein, a highly efficient, simple, base-free, chemoselective and environmentally-benign strategy was developed for the reduction of nitro compounds using NaBH4 as a hydrogen and electron source in the presence of a bimetallic and low-cost nanocatalyst (Fe3O4@Ni-Co-BTC NPs). Thanks to inimitable structure of Fe3O4@Ni-Co-BTC NPs, this nanostructured catalyst exhibits superior catalytic performance for the reduction of a wide library of electron-donating and electron-withdrawing aromatic, heteroaromatic, heterocyclic and aliphatic nitro compounds. Interestingly, the aforesaid nanocatalyst showed high reactivity and chemoselectivity for the reduction of the nitro group in the presence of other reducible functional groups such as COOH, CHO, COCH3, CN, NHAc and OCOCH3. Furthermore, due to the superparamagnetic nature of Fe3O4@Ni-Co-BTC NPs, it could be easily separated from the reaction mixture and reused for at least seven consecutive recycle runs while its activity and selectivity was preserved. Performing the reaction at room temperature and in a green media is another notable feature of the present method.