Synthesis and Characterization of New M-Triazole Complexes (M = Co, Cu, Zn)

Three new complexes with the ligand 3,5-diamino-1,2,4-triazole (Hdatrz), [Co-3(mu(2)-Hdatrz)(6)(H2O)(6)]center dot(NO3)(8)center dot 4H(2)O (1), [Cu-3(mu(2)-Hdatrz)(4)(mu(2)-Cl)(2)(H2O)(2)Cl-2]center dot Cl-2 center dot 4H(2)O center dot 2C(2)H(5)OH (2) and {[Zn-2(mu(2)-SO4) (mu(3)-datrz)(2)]center dot 2H(2)O}(n) (3) have been synthesized and structurally characterized. Complex I has a linear trinuclear mixed-valence cobalt structure with six neutral triazole ligands in the N(1), N(2)-bridging mode. The central cobalt atom, Co(1), is coordinated to six nitrogen atoms (octahedral) whereas the terminal cobalt atom, Co(2), is coordinated to an N3O3 moiety (octahedral). In complex 1, the uudd cyclic water clusters, nitrate anions and the trimeric cations are linked to a supramolecular structure. Complex 2 features a linear trinuclear copper(II) core, with four N(1), N(2)-bridging triazole ligands and two chlorido bridges. The central copper atom is coordinated to ail N4Cl2 moiety (octahedral) whereas the terminal copper is coordinated to ail N2Cl2O moiety (square-pyramidal). In complex 2, tetrahedral hydrogen bonding interactions play an important role to form a supramolecular network. Complex 3 exhibits a polymeric structure, with N(1), N(2), N(4)bridging triazolate ligands and sulfate bridges, in which zinc is coordinated to an N3O moiety (tetrahedral). In complex 3, water molecules and sulfate anions construct the sulfate-water supramolecular chain with hydrogen bonding interactions. In addition, the complexes were investigated by elemental analyses, IR spectroscopic, and thermogravimetric measurements.