LAUSR

Magnetically recoverable and environmentally friendly Cu-based heterogeneous catalyst has been synthesized for the one-pot conversion of aldehydes to their corresponding primary amides. The Fe3O4@SiO2 nanocomposites were prepared by synthesis of Fe3O4 magnetic nanoparticles (MNPs) which was then coated with a silica shell via Stober method. Bi-functional cysteine amino acid was covalently bonded onto the siliceous shell of nanocatalyst. The CuII ions were then loaded onto the modified surface of nanocatalyst. Finally, uniformly dispersed copper nanoparticles were achieved by reduction of CuII ions with NaBH4. Amidation reaction of aryl halides with electron-withdrawing or electron-donating groups and hydroxylamine hydrochloride catalyzed with Fe3O4@SiO2@Cysteine-copper (FSC-Cu) MNPs in aqueous condition gave an excellent yield of products. The FSC-Cu MNPs could be easily isolated from the reaction mixture with an external magnet and reused at least 8 times without significant loss in activity.