2,5-噻吩二甲酸与菲咯啉构筑的稀土配合物:晶体结构,荧光性质和对Cu^(2+)离子的荧光传感

Lanthanide Complexes with 2,5-Thiophenedicarboxylate and 1,10-Phenanthroline:Crystal Structures, Fluorescence Properties and Luminescence Sensing for Cu^(2+) Ion

稀土硝酸盐和2,5-噻吩二甲酸与菲咯啉在水热反应条件下合成了3个新的配合物,[Ln(2,5-tdc)1.5(phen)(H2O)]n(Ln=Gd(1),Tb(2),Dy(3);2,5-tdc=2,5-噻吩二甲酸根,phen=菲咯啉)。通过X射线单晶衍射确定了它们的晶体结构。配合物1~3为同构的2D网络结构。配合物1在340 nm激发下出现最大发射中心位于366和387 nm的宽峰,可归属于配体的π*-π跃迁发射。配合物2在365 nm紫外灯照射下发绿光,其荧光发射光谱中出现了4个尖峰,位于491、545、588和620 nm处,对应于Tb3+的5D4→7FJ(J=6~3)跃迁。配合物2的荧光寿命显示为单指数衰减,其值为(0.123±0.005)ms。配合物3的发射光谱中出现了2个尖峰,位于482和575 nm处,分别对应于Dy3+的4F5/2→6H15/2和4F5/2→6H13/2跃迁。另外,研究了配合物2的荧光传感能力,该配合物可作为荧光探针检测水溶液中的Cu2+离子。

Three lanthanide-organic frameworks [Ln（2,5-tdc）Ls（phen）（H2O）]n （Ln=Gd （1）, Tb （2）, Dy （3）; 2,5-tdc= 2,5-thiophenedicarboxylate and phen=1,10-phenanthroline） have been synthesized and characterized by X-ray single-crystal diffraction. Complexes 1-3 feature isostructural 2D structures. The luminescence properties of 1-3 were investigated. Under the excitation of 340 nm, the emission spectrum of complex 1 shows a broad band centre at 366 and 387 nm, which plausibly arises from ligand-centered π-π transition within the ligands Complex 2 displays green emission and shows four emission peaks at 491,545, 588 and 620 nm, corresponding to 5D4→7FJ （J=6-3） transitions of Tb3＋ under the excitation of 310 nm. The 5D4emission decay curve reveals a monoexponential behavior with the lifetime value of （0.123±0.005） ms. The emission spectrum of complex 3 records two peaks of 482 and 575 nm, corresponding to the 4F5/2→6H15/2 and 4F5/2→6H13/2 transition of Dy3＋, respectively, under the excitation of 330 nm. Moreover, the fluorescence sensing ability of complex 2 was investigated, revealing that it can be used as a fluorescence probe to detect Cu2＋ in aqueous solution. CCDC： 1036885, 1; 1036884, 2; 1036886, 3.