溶剂控制的铜基金属-有机框架物的合成与荧光性能

金属-有机框架物在荧光识别领域表现出良好的应用前景,为探究合成更为精确识别的物质,本文利用二羧酸配体(H_2PAIA=5-丙酰胺基间苯二甲酸)和硝酸铜通过溶剂调控合成了两例结构不同的铜基金属-有机框架物(MOFs){Cu(PAIA)(H_2O)]·2H_2O}(1)和{Cu_3(PAIA)_2(DMSO)(Pyridine)_(1.5)]}(DMSO:二甲基亚砜;Pyridine:吡啶)(2)。尽管由相同的金属离子和有机配体构筑而成,但显示出具有显著溶剂导向特征的不同框架结构:配合物1为三维NbO型拓扑结构,而配合物2为二维sql型拓扑结构。正是由于这些结构上的差异,导致两个配合物的荧光识别性能和疏水性能展现出显著的不同。配合物1能够同时识别Pb~(2+)和Ag~+离子,而配合物2只能识别Pb~(2+),对Ag~+没有明显的信号响应。配合物1的疏水角85.06°比配合物2的52.71°有显著的增加。

Solvent-Dependent Synthesis and Fluorescent Properties of Cu(Ⅱ) Metal-Organic Frameworks

Metal-organic frameworks have promising potentials of for applications in the areas of fluorescence recognition. To explore more accurate identification of synthetic substancess, we synthesized two copper metal-organic frameworks(MOFs), {Cu(PAIA)(H₂O)]·2H₂O}(1) and {Cu₃(PAIA)₂(DMSO)(Pyridine)_1.5]}(2)(H₂PAIA=5-(propionyl-λ2-azanyl)isophthalic acid; DMSO=dimethyl sulphoxide), by the solvothermal reaction in the presence of H₂PAIA under different solvents(H₂O and DMSO/H₂O). Synthetic investigations and structural analyses reveal that both MOFs show distinct frameworks with remarkable solvent-directed feature, although they are assembled from the same starting materials, i.e., Cu(NO₃)₂·3H₂O with H₂PAIA for complexes 1 and 2. The topological structures and fluorescent properties of the two coordination compounds show a significant difference. Complex 1 is a three-dimensional NbO-type topology, while the complex 2 is a two-dimensional sql-type topology. Complex 1 exhibits fluorescent recognition to both Pb²⁺ and Ag⁺ ions, while complex 2 exhibits fluorescent recognition of Pb²⁺ ion. The water contact angle for complex 1 is 85.06°, while the water contact angle for complex 2 is 52.71°.