含共轭三烯吡啶配体的配位聚合物的合成、结构及荧光性质

Synthesis, Structure, and Luminescence Properties of Coordination Polymers Containing Conjugated Triene Pyridine Ligands

将1,6-双(4-吡啶基)-1,3,5-己三烯(bphte)和镉盐分别与2种羧酸配体(2,5-二呋喃二甲酸(2,5-H_(2)FDC)及1,3,5-均苯三甲酸(1,3,5-H_(3)BTC))进行溶剂热反应,得到2个配位聚合物:[Cd(2,5-FDC)(bphte)(H_(2)O)]_(n)(1)和[Cd(1,3,5-HBTC)(bphte)]_(n)(2)。对配合物1和2分别进行了元素分析、红外光谱、单晶X射线衍射、粉末X射线衍射和热重分析表征。配位聚合物1具有spl拓扑结构的三维互穿超分子框架,而配合物2是由bphte配体交叉连接一维链[Cd_(2)(1,3,5-HBTC)_(2)]_(n)形成的三维结构。配合物1和2在固态时表现出不同的荧光性质。配合物2遇到水溶液中Fe^(3+)会发生荧光猝灭,因此以其作为荧光探针对水溶液中Fe^(3+)进行了选择性荧光检测,它对Fe^(3+)的检测限可达到0.013μmol·L^(-1)。这种荧光猝灭过程可归因于Fe^(3+)离子的吸收带与配合物2的激发带之间存在部分重叠。

Solvothermal reactions of the conjugated triene pyridine ligand 1,6-bis(4-pyridyl)-l,3,5-hexatriene(bphte)and Cd(Ⅱ)salts in the presence of auxiliary carboxylic acid ligands(2,5-furandicarboxylic acid(2,5-H_(2)FDC)and 1,3,5-trimesic acid(1,3,5-H_(3)BTC))gave rise to two coordination polymers[Cd(2,5-FDC)(bphte)(H_(2)O)]_(n)(1)and[Cd(1,3,5-HBTC)(bphte)]_(n)(2),respectively.Both complexes were characterized by elemental analysis,IR,single-crystal X-ray diffraction,powder X-ray diffraction,and thermogravimetric analysis.Complex1has a 3D framework with an spl topological structure,while complex2holds another 3D architecture formed by bridging 1D[Cd_(2)(1,3,5-HBTC)_(2)]_(n) chains via bphte ligands.Both complexes exhibited luminescence emission in the solid state.Complex2showed an emission quenching phenomenon in Fe^(3+)aqueous solution,and thus was used as an excellent fluorescence probe to selectively detect Fe^(3+)in water with a low detection limit of 0.013μmol·L^(-1).The above emission quenching mechanism is likely due to the overlap between the absorption band of the Fe^(3+)ion and the excitation band of2.CCDC:2168533,1;2168532,2.