作者:A. A. M. Aly、S. Z. Vatsadze、B. Walfort、T. Rüffer、H. Lang
DOI:10.1134/s0036023617120038
日期:2017.12
The reaction of the silver salts AgX (a: X = BF4 (-), b: X = ClO4 (-), c: X = OTf-) with alpha,alpha'-di(3/4-pyridylmethylene)cycloalkanones (L-1-L-3) and piperidones (L-4-L-7) results in the formation of coordination products of general composition [AgX(L (n) )(solvent)] and [AgX(L (n) )] (L (n) = L-1-L-7). All complexes were characterized by elemental analysis and IR-spectroscopy. The structures of [Ag(ClO4)(L-1)(MeCae N)](a) (1b center dot MeCae N) and [Ag(ClO4)(L-1)](a) (1b) in the solid state are reported. In both structures Ag(L-1)}(+) building units are linked to each other via Ag-N-pyridine primary bonds resulting in the formation of infinite chains. In both structures the ligands L-1 are fixed in transoid conformations, thus forming zig-zag polar chains. The structure of 1b center dot MeCae N consists of pairs of tightly and loosely stacked chains. The tightly packed chains are weakly coupled by perchlorate anions acting as mu-bridges in between Ag(I) centers as well as by pi-pi-stacking interactions of unsaturated fragments of the respective ligands. In contrast, polar 2D layers composed of Ag(L-1)} (m) (m+) chains, which interdigitate via multiple weak interactions by Ag-O contacts, are found in the solid structure of 1b. The dissolution of coordination products in coordinating solvents like MeCN or DMSO leads to the decomposition of complexes due to formation of silver-solvent coordination compounds. The coordination products 1-5 are stable in solid state against exposure to the ambient light, whereas solutions of the compounds, especially in DMSO-d (6), appeared to be photochemically labile. As revealed by NMR spectroscopic studies, the organic components undergo trans-cis isomerization.