Highly chemo- and regioselective reduction of aromatic nitro compounds using the system silane/oxo-rhenium complexes
Rita G de Noronha1, Carlos C Romão, Ana C Fernandes
1Instituto de Tecnologia Química e Biológica, Universidade Nova de Lisboa, Oeiras, Portugal.
Abstract:
The reduction of aromatic nitro compounds to the corresponding amines with silanes catalyzed by high valent oxo-rhenium complexes is reported. The catalytic systems PhMe(2)SiH/ReIO(2)(PPh(3))(2) (5 mol %) and PhMe(2)SiH/ReOCl(3)(PPh(3))(2) (5 mol %) reduced efficiently a series of aromatic nitro compounds in the presence of a wide range of functional groups such as ester, halo, amide, sulfone, lactone, and benzyl. This methodology also allowed the regioselective reduction of dinitrobenzenes to the corresponding nitroanilines and the reduction of an aromatic nitro group in presence of an aliphatic nitro group.
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