A Facile and Efficient Oxalyldihydrazide/Ketone‐Promoted Copper‐Catalyzed Amination of Aryl Halides in Water

Abstract A novel three‐component catalyst CuO/oxalyldihydrazide/hexane‐2,5‐dione was a very convenient, economic, and effective catalytic system for the Ullmann‐type C–N coupling reaction in water. Both aryl bromides and aryl iodides could be aminated by a variety of amines even at room temperature or with heating to afford very good isolated yields. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2009)