Silver coordination chemistry of a new versatile "Janus"-type N2,O2-bichelating donor, formation of an unprecedented supramolecular network of binuclear silver building blocks containing a five-coordinate β-diketonate, and isolation of unexpected silver-tin-silver heterotrimetallic complexes from silver metathesis reactions

Synthetic, spectroscopic, and single-crystal X-ray studies are reported for several complexes of silver(l) with the N-2,O-2-bichelating Q(py) ligand (HQ(py) = 1-(2-pyridyl)-3-methyl-4-trifluoroacetylpyrazol-5-one). Direct interaction between HQ(py) and AgNO3 in methanol, in the presence of NaOCH3, affords derivative Ag(Q(py)), showing a polynuclear structure composed of dinuclear building blocks with two different Ag environments and two Q(py) donors differently connected. By adding neutral ligands such as PR3 (R = Ph, CY, C6H4-o-CH3, C6H4-p-F, Bu-i) to Ag(Q(py)), dinuclear Ag(Q(py))(PR3) derivatives have been isolated, containing bridging N-2,O-exotridentate Q(py) donors spanning a pair of AgPR3 moieties. Reaction of Ag(Q(py))(PPh3) With excess PPh3 produces the mononuclear Ag(Q(py))(PPh3)(2) containing N-2-chelate Q(py). Ag(Q(py)) interacts with 1,2-bis(diphenylphosphino)ethane (dppe) yielding the derivative Ag(Q(py))(dppe), having a polynuclear structure in the solid state which is seemingly disrupted in solution, with the formation of two new species, a mononuclear neutral compound and a dinuclear ionic one. By the interaction of Ag(Q(py)) with nitrogen donors L (L = imidazole (imH), 1-methylimidazole (Meim), 1-methyl-2-mercaptoimidazole (Hmimt), 1,10phenanthroline (phen)), mononuclear species Ag(Q(py))(L) have been obtained, where Q(py) is coordinated to silver in N-2-chelating mode. Ag(Q(py))(PPh3)(2) reacts with SnRCl3 (R = Ph, Bun) affording heterotrimetallic [{(Ph3P)(2)AgCl}(2)SnRCl3] derivatives.