First examples of a modulated bridging μ2-1:2κN-triazine in double helical silver compounds. Experimental and theoretical evidence

The synthesis of several silver double helices containing bis(3,5dimethylpyrazolyl)-6-(R)-s-triazine ligands is described. The structure of two of them has been determined by X-ray difraction. Both derivatives represent the first reported examples of a new interaction mode for a triazine ring that involves a triazine N atom bridging two metal centers. Argentophilic contacts are also present. The Ag−N and Ag−Ag interactions have been demonstrated by theoretical studies, which also showed the clear influence of weak interactions with the counteranion and the effect of the symmetry of the triazine substituent. The different donor characters of these substituents allows a modulation of the strength of the bridging Ag−Ntriazine interaction. Double π−π stacking, anion−π interactions, hydrogen bonds, and hydrophobic effects are observed in an unusual highly symmetrical interpenetrated three-dimensional superstructure.The Spanish Ministry of Science and Innovation (MICINN) and the Junta de Comunidades de Castilla-La Mancha (projects CTQ2008-03783 and PCI08-0054) are acknowledged for financial support.Peer reviewe