Copper Catalyzed N-arylation Reaction Of Arylboronic Acids

Arylamines are important compounds widely employed in biochemical, pharmaceutical and photoelectric conversion material fields. Significant progress was achieved in the past years for transition metal-catalyzed N-arylation reaction. In comparison with Pd and Ni, copper is a cheaper metal with lower-toxicity. Arylboronic acids have some advantages, such as low toxicity, good functional group-tolerance, stability to air or moisture. In recent years, copper salts and complexes have been extensively utilized as catalysts for the Chan-Lam reaction between boronic acids and amines. However, to the best of our knowledge, the employing of cheap and abundant nitrogen compounds in Chan-Lam reaction was rarely reported or studied before. In this paper, recent advances in the metal-catalyzed reactions to access arylamines were reviewed, and two kinds of these reactions were studied: (1) We developed a facile method to access di-arylamine through the copper-catalyzed coupling reaction of arylboronic acids with aqueous ammonia. (2) Copper-catalyzed coupling reaction of hydroxylamine hydrochloride and arylboronic acids was described, providing a simple and efficient methodology for the synthesis of symmetric diaryl amines. The reaction showed good functional groups tolerance.The new approaches for the synthesis of N-aryl moiety are developed, which enjoy the advantages of mild reaction conditions, simple operation, moderate to high yields, and commercially available materials.