2-Pyridinyl β-ketones as new ligands for room-temperature CuI-catalysed C–N coupling reactions
作者:Deping Wang、Ke Ding
DOI:10.1039/b821212k
日期:——
2-Pyridinyl β-ketones were identified as new efficient ligands for CuI-catalysed N-arylation of aliphatic amines at room temperature with great selectivity and substrate scope tolerance.
to be effective ligands for the Cu-catalyzedamination of less reactive (hetero)aryl chlorides. A wide range of functionalized (hetero)aryl chlorides reacted with various aliphatic amines to afford the desired products in good to excellent yields under the catalyst of CuI/2-aminopyridine 1-oxides. Furthermore, the catalyst system worked well for the coupling of cyclic secondary amines and N-methyl benzylamine
A room-temperature and PTC-free copper-catalyzed N-arylation of aliphatic amines in neatwater has been developed. Using a combination of CuI and 6,7-dihydroquinolin-8(5H)-one oxime as the catalyst and KOH as the base, a wide range of aliphatic amines are arylated with various aryl and heteroaryl halides to give the corresponding products in up to 95% yield.
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