Cu Nanoparticles in PEG: A New Recyclable Catalytic System for N-Arylation of Amines with Aryl Halides

A new protocol for the N-arylation of aryl halides with anilines using Cu nanoparticles in polyethylene glycol (PEG) as an efficient and reusable catalytic system has been developed. The reaction did not require any cocatalyst. Various solvents were screened, and PEG(400) provided the best results. The studies showed that the mechanism of catalytic action is dependent on the size of the nanoparticles. The Cu nanoparticles and PEG were recyclable and retained their activity. This newly developed protocol was also found to be suitable for the cross coupling of N-H heterocycles with iodobenzene. The present methodology offers several advantages, such as excellent yields, short reaction times, and milder reaction conditions.