Five Ag(Ι) metal–organic coordination complexes with dinuclear units: Synthesis and crystal structures

Five new Ag(Ι) metal–organic coordination complexes with dinuclear structure units, Ag2(L1)2(NO3)2 (1), Ag2(L2)3(ClO4)2 (2), Ag2(L2)3(NO3)2 (3), [Ag2(L3)3(BF4)2](H2O)0.25 (4) and [Ag2(L4)2(CH3OH)2](ClO4)2 (5) were synthesized, using ligands L1 (N-1,3,4-thiadiazol-2-yl-propionamide), L2 [N-(5-methyl-1,3,4-thiadiazol-2-yl)-propionamide], L3 (N-1,3,4-thiadiazol-2-yl-benzamide) and L4 [N-(5-methyl-1,3,4-thiadiazol-2-yl)-benzamide] as building blocks. All complexes were structurally characterized by elemental analyses, IR spectroscopy and X-ray diffraction. Complexes 1–5 have dinuclear structure units. Compounds 1 and 5 are centrosymmetric different from 2 to 4, in 2–4 two distinct Ag(Ι) were observed in the independent crystallographic dinuclear unit. In 1, 4 and 5, ligands bridge two Ag(Ι) atoms to form an approximately planar binuclear structure containing six-membered ring (Ag–N–N–)2. In complexes 1–5, the Ag⋯Ag weak interactions were observed between the two non-bonding Ag(Ι) centers in the dinuclear unit and the Ag⋯Ag distance are in 3.150–3.481 Å.