Experimental and theoretical evidence of unsupported Ag–Ag interactions in complexes with triazine-based ligands. Subtle effects of the symmetry of the triazine substituents
作者:M. Pilar Carranza、Blanca R. Manzano、Félix A. Jalón、Ana M. Rodríguez、Lucía Santos、Miquel Moreno
DOI:10.1039/c3nj00738c
日期:——
The synthesis of several dimeric silver compounds containing bis(pyrazol-1-yl)-6-(R)-s-triazine or bis(3,5-dimethylpyrazol-1-yl)-6-(R)-s-triazine ligands and coordinated triflate is described. The structures of two of the compounds have been determined by X-ray diffraction. Both derivatives show ligand-unsupported argentophilic contacts and different supramolecular interactions such as ÏâÏ stacking, CHâÏ or anionâÏ interactions. Hydrogen bonds are also established between the monomers. The relative orientation of the two monomers, which is mainly influenced by the formation of hydrogen bonds, reflects the symmetry of the R substituent of the triazine ring. Theoretical DFT calculations and Natural Bond Order (NBO) analysis of the two dimers further support the existence of the argentophilic interactions. Differences between the optimized and real structures can be mainly attributed to the underestimation of the ÏâÏ stacking interaction in the DFT studies.
First Examples of a Modulated Bridging μ<sub>2</sub>-1:2κ<i>N</i>-Triazine in Double Helical Silver Compounds. Experimental and Theoretical Evidence
作者:M. Pilar Carranza、Blanca R. Manzano、Félix A. Jalón、Ana M. Rodríguez、Lucía Santos、Miquel Moreno
DOI:10.1021/ic902563d
日期:2010.4.19
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−πinteractions, hydrogen bonds