The use of coumarin-based ligands was examined in copper-catalyzed C-N cross-coupling reactions. It was found that 3-acetylcoumarin constituted a new, practical ligand for the copper-catalyzed N-arylation of aliphatic amines and imidazole with aryl iodides at room temperature. Aryl bromides could also be aminated efficiently at 80 ˚C. This readily available catalyst system, namely copper(I) iodide
Tetramethylammonium hydroxide was used as a base instead of a traditional inorganic base in this copper-catalyzed system and some satisfactory results were obtained. Various functional groups were compatible under this reaction condition. (C) 2009 Elsevier Ltd. All rights reserved.