4. ConclusionIn conclusion, we developed a Cu2O/l-proline/EtOH catalystsystem for the direct conversion of aryl and heteroaryl bromidesinto the corresponding iodides. This new method represents sev-eral good features: the reaction conditions are mild, the iodidesource (KI) and solvent (EtOH) are cheap and readily available,and the substrate scope is broad. In addition, the new method hasgood functional group tolerance. Further studies focusing on thebromide–fluoride exchange reaction are currently underway in ourlaboratory