High yield and selective electrocatalytic reduction of nitroarenes to anilines using redox mediators

Anilines are major commodity chemicals used extensively in the production of pharmaceuticals, dyes, and polymers. However, the typical methods for synthesizing anilines suffer from poor environmental sustainability. Here, we report an electrocatalytic route for the production of anilines that works in aqueous solution at room temperature and pressure, where the electrons and protons required to reduce the nitrobenzene precursors are obtained from water. Excellent selectivities are obtained for a range of anilines, including species with ortho-iodides that are very challenging to obtain by other methods. Our approach relies on the use of a polyoxometalate redox mediator that shuts off the direct electro-reduction of the nitrobenzene at the electrode surface and thus prevents unproductive side reactions. Given the scale and current environmental impact of global aniline production, this electrochemical route holds promise for the development of more sustainable processes for the production of these vital chemical feedstocks.