Syntheses and Crystal Structures of Nickel(II) Coordination Compounds with 2-(5-methyl-1,3,4-thiadiazol-2-ylthio)acetic Acid

Two coordination compounds [Ni(mtyaa)2(H2O)4]·4(H2O) (1) and [Ni(4,4′-bipy)2(mtyaa)2(H2O)2]·2H2O (2) (Hmtyaa is 2-(5-methyl-1,3,4-thiadiazol-2-ylthio)acetic acid; 4,4′-bipy is 4,4′-bipyridine) have been synthesized and structurally characterized by single-crystal X-ray diffraction, elemental analysis, FTIR spectra, thermal analysis and powder X-ray diffraction. compounds 1 and 2 crystallize in the triclinic and monoclinic, space group is P1 and P21/n, respectively. Single-crystal X-ray diffraction analysis indicate that both nickel atoms adopt six-coordinated distorted octahedral coordination mode in compounds 1 and 2. Hydrogen bonds between coordinated and free water molecules with carboxylate oxygen atoms connected single molecules in compound 1 into three dimensional network. Compound 2 is connected into two dimensional layered structure by hydrogen bonds between coordinated and free water molecules with carboxylate oxygen atoms and nitrogen atoms.