Gold complexes as catalysts: Chemoselective hydrogenation of nitroarenes

Nitro groups on different compounds – containing double bonds, carbonyl, nitrile or halide groups – have been successfully hydrogenated with well-defined homogeneous gold and palladium complexes as catalysts using a batch reactor under low H2 pressure. Gold complexes show high chemoselectivity towards reduction of the nitro group at near-complete conversion of the substrate. The corresponding amino derivatives are isolated in high yields.

The reduction of a wide range of organic nitro compounds to the corresponding amines in good to excellent yields has been achieved using Au(III)–Schiff base and Au(I) catalysts. This method is mild, exceedingly efficient and highly selective. The azoxy, azo and hydrazo compounds, as the usual side products of reduction under basic conditions were not observed in the reaction system.Figure optionsDownload as PowerPoint slide