A copper-catalyzed three-component assembly of cyanamides, 2-cyanoarylboronic acids and amines has been developed, providing functionalized quinazolin-4(H)-imines. Subsequent access to benzimidazo[1,2-c]quinazolines is achieved building again on copper-catalysis. One pot hydrolysis of quinazolin-4(H)-imines to quinazolin-4(3H)-ones is also described. Guanidine formation, cyclization and intramolecular CÀ H bond amination are key features of the process fully mediated by copper.

A copper-promoted three-component synthesis of 2-aminobenzimidazoles (1) or of 2-aminoquinazolines (2) involving cyanamides, arylboronic acids, and amines has been developed. The operationally simple oxidative process, performed in the presence of K2CO3, a catalytic amount of CuCl2·2H2O, 2,2'-bipyridine, and an O2 atmosphere (1 atm), allows the rapid assembly of either benzimidazoles or quinazolines starting from aryl- or benzyl-substituted cyanamides, respectively. In this process, the copper promotes the formation of three bonds, two C-N bonds, and an additional bond resulting from C-H functionalization event.