Three 1-(4-Hydroxyphenyl)-1H-1,2,4-triazole-based Cd(II)Coordination Polymers Directed by Aromatic Polycarboxylate Coligands

摘要

The reactions of 1-(4-hydroxyphenyl)-1H-1,2,4-triazole(hptrz)and inorganic Cd(II)salts with different aromatic polycarboxylic acids in mixed-solvent led to the formation of three new crystalline coordination polymers,{[Cd(H2O)2(hptrz)(Hbtc)]_n·CH3OH·H2O} 1,[Cd2(H2O)2(hptrz)2(tp)2]_n 2,and {[Cd(H2O)2(hptrz)-(OH-ip)]_n·DMF·H2O} 3(H3btc=1,3,5-benzenetricarboxylic acid,H2tp=terephthalic acid,and OH-H2ip=5-hydroxyisophthalic acid),which were fully characterized by elemental analysis,IR spectroscopy,single crystal X-ray crystallography,thermogravimertric analysis and luminescence spectra.Structure determination revealed that one-dimensional(1-D)polymeric chains for 1 and 3,and 2-D layered structure for 2 are significantly directed by the coordination mode of the carboxylate groups from aromatic coligands.In contrast,the terminal hptrz ligand affords its uncoordinated phenolic OH group to form classical H-bond interactions with coordinated water and/or carboxylate groups,which are responsible for the formation of 3-D supramolecular networks.In addition,the three solid coordination polymers with considerable thermal stability present strong hptrz-based fluorescence emissions at room temperature.