Abstract
Three 2-D layered coordination polymers with (4,4) topology, {[Cu(trzp)2(H2O)]·1.18H2O} n (1), {[Co(trzp)2(H2O)2]·2H2O} n (2), and {[Cd(trzp)2(H2O)]·2H2O} n (3), have been synthesized with the flexible, bifunctional ligand 1H-1,2,4-triazole-1-propionate (trzp−) as a two-connected bridge. In addition, a complicated 3-D MOF [Ag3(trzp)2(NO3)] n (4) has been obtained with the help of Ag⋯Ag interactions and trzp− as a four-connected linker. Htrzp and 1–4 have been characterized by single-crystal X-ray diffraction, elemental analysis, and infrared spectroscopy. The structural analysis showed that Htrzp has a gauche conformation in the solid state. However, both gauche and trans conformers of trzp− are observed in the crystals of 1; only one conformer of trzp− exists in the other three compounds (trans conformation in 2 and 3, and gauche conformation in 4). The thermal behaviors of 1–4 have been examined by thermal gravimetric analysis under nitrogen, which revealed that metal cyanide salts M(CN) n (M = Cu(II), Co(II), Cd(II), and Ag(I), n = 1 or 2) may be an intermediate pyrolytic decomposition product of the corresponding compounds.
Acknowledgements
This work was financially supported by the Guangxi Natural Science Foundation of China (grant no. 2010GXNSFF013001, 0832023) and Scientific Research Foundation of Guangxi Normal University.