N‐(4‐Thiazolylmethyl)Morpholine N‐Oxide as N,O‐Bidentate Ligand for Copper‐Catalyzed Ullmann‐Type N‐Arylation of Azoles/Amines with Aryl Halides.

An effective and practical protocol for the CuI‐catalyzed Ullmann‐type N‐arylation of azoles/amines with aryl halides is reported. The key strategy is the employment of CH2 linker N,O‐bidentate ligands, especially N‐(4‐thiazolylmethyl)morpholine N‐oxide, as superior supporting ligands. The highly efficient C−N coupling reactions between various azoles/amines and aryl halides bearing different functional groups can be achieved under CuI/N‐(4‐thiazolylmethyl)morpholine N‐oxide catalytic system, affording a variety of N‐arylated products. The use of cheap copper(I) salt and readily available N,O‐bidentate ligands make this procedure more attractive for synthesis of valuable functionalized nitrogen‐containing heterocyclic compounds. [ABSTRACT FROM AUTHOR]