Copper-Catalyzed C(aryl)–N Bond Formation

Abstract

Although requiring the use of stoichiometric amounts of metal and harsh conditions, the copper-mediated coupling reactions of aryl halides with amines and phenols (Ullmann condensations), amides and carbamates (Ullmann–Goldberg condensations), or activated methylene compounds (Ullmann–Hurtley condensations) have been for a long time useful methods for the formation of C(aryl)–N, C(aryl)–O, and C(aryl)–C bonds. In 2001, a renaissance of the Ullmann reaction has been initiated with the discovery of versatile new copper catalytic systems for C–C, C–N, or C–O coupling under mild temperature conditions. This chapter covers more specifically the copper-catalyzed C(aryl)–N bond formation via the coupling of aryl halides with nitrogen nucleophiles such as N-heterocycles, amines, anilines, amides, ammonia, azides, hydroxylamines, nitrite salts or phosphonic amides. The C(aryl)–N bond formation as a result of the coupling between these nucleophiles and arylboronic acids (the Chan–Lam reaction) will be also presented. It is worth noting that this chapter mainly focuses on the most significant results and important breakthroughs in this field.