Stable and reusable nanoscale Fe₂O₃-catalyzed aerobic oxidation process for the selective synthesis of nitriles and primary amides

The sustainable introduction of nitrogen moieties in the form of nitrile or amide groups in functionalized molecules is of fundamental interest because nitrogen-containing motifs are found in a large number of life science molecules, natural products and materials. Hence, the synthesis and functionalization of nitriles and amides from easily available starting materials using cost-effective catalysts and green reagents is highly desired. In this regard, herein we report the nanoscale iron oxide-catalyzed environmentally benign synthesis of nitriles and primary amides from aldehydes and aqueous ammonia in the presence of 1 bar O₂ or air. Under mild reaction conditions, this iron-catalyzed aerobic oxidation process proceeds to synthesise functionalized and structurally diverse aromatic, aliphatic and heterocyclic nitriles. Additionally, applying this iron-based protocol, primary amides have also been prepared in a water medium.