C-NH2 bond formation mediated by iridium complexes

In the presence of phosphanes (PR3), the amido-bridged trinuclear complex [{Ir(μ-NH2)(tfbb)}3] (tfbb=tetrafluorobenzobarrelene) transforms into mononuclear discrete compounds [Ir(1,2-η2-4-κ-C12H8F 4N)(PR3)3], which are the products of the C-N coupling between the amido moiety and a vinylic carbon of the diolefin. An alternative synthetic approach to these species involves the reaction of the 18-e- complex [Ir(Cl)(tfbb)(PMePh2)2] with gaseous ammonia and additional phosphane. DFT studies show that both transformations occur through nucleophilic attack. In the first case the amido moiety attacks a diolefin coordinated to a neighboring molecule following a bimolecular mechanism induced by the highly basic NH2 moiety; the second pathway involves a direct nucleophilic attack of ammonia to a coordinated tfbb molecule.Financial support from project CTQ2012-35665, the CONSOLIDER INGENIO-2010 program under the projects MULTICAT (CSD2009-00050), the Factoría de Cristalización (CSD2006-0015), and the DGA-FSE are acknowledged.Peer Reviewe