ABSTRACT
Abstract This paper deals with the development of industrially applied precious metal powder catalysts (PMPC) and activated base metal catalysts (ABMC, otherwise known as sponge metal or skeletal catalysts) for the selective hydrogenation of substituted aliphatic and aromatic nitro compounds to the corresponding arnines. Since 40 - 50 % of the hydrogenation reactions in fine, intennediate, and pharmaceutical chemistry deal with the reduction of nitro groups, this paper reviews the efficient use of different catalysts in such processes. Test results of improved PMPC and ABMC are discussed for the hydrogenation of aliphatic nitro compounds and nitroarenes. The basic principles of nitro group reduction and concepts for developing tailored catalysts for each class of the aforementioned nitro compounds are also presented. This paper underscores the ongoing efforts in industry on catalyst improvements contributing to environmentally benign and highly efficient processes.
