Visible-light-induced iron-catalyzed reduction of nitroarenes to anilines

An efficient visible-light-induced iron-catalyzed reduction of nitroarenes to anilines by using N-ethylmorpholine (NEM) as a reductant under mild conditions has been developed. The reaction proceeds with photosensitizer-free conditions and features good to excellent yields and broad functional group tolerance. Preliminary mechanistic investigations showed that this reaction was conducted via ligand-to-metal (NEM to Fe3+) charge transfer and nitro triplet biradical-induced hydrogen atom transfer processes.