Recent Developments in Photocatalytic Reduction of Nitro Compounds to Valuable Scaffolds

Abstract

The reduction of nitro compounds is one of the fundamental organic transformations and ascertain wide applicability in industrial chemistry, synthesis of valuable scaffolds, fine chemical synthesis as well as environmental applicability for decontamination process. The transformation involves the conversion of nitro compounds to valuable scaffolds including amino, nitroso, hydroxyl amines, azo and hydrazo compounds. Conventional approaches for the reduction of nitro compounds involves the environmentally harmful stoichiometric reagents, high boiling reaction media, tedious processes, and harsh reaction conditions with high temperature and pressure. Additionally, the selectivity always remains a serious concern associated with the process due to the possibilities of several stable intermediate formation in the reaction pathway of reduction of nitro compounds. Nitro compounds are also of serious environmental concerns being a part of most harmful and high-priority classes of pollutants mainly released from industrial effluents, agricultural waste, and human sewage. A simple degradation of these pollutants bearing nitro group just removes the pollutants, however, the selective reduction of nitro group to valuable functionalities as mentioned above provides the industrially important scaffolds. Herein, the present review article is focused on the recent developments in the photocatalytic reduction of nitro compounds to valuable scaffolds.