Copper-catalyzed cyanation of heteroaryl bromides:: A novel and versatile catalyst system inspired by nature

An improved copper catalyst system for the cyanation of heteroaryl halides leading to substituted heteroaryl nitriles is described. The catalyst system consists of simple Cul and N-alkyl-imidazoles, and mimics known Cu-containing metalloproteins. It is stable, commercially available, cheap and easily tunable. By using inexpensive and non-toxic K-4[Fe(CN)(6)] and the novel Cu catalysts we were able to cyanate both activated and non-activated heteroarenes with high yield and selectivity. The generality of the procedure is demonstrated by a variety of different examples, some of which did not react under other known methods.