2-[3-氰基呋喃-2(5H)-亚基]丙二腈衍生物的合成及其识别S^(2-)

Synthesis of a 2-[3-cyanofuran-2(5H)-subunit]malononitrile derivative and its recognition of S^(2-)

设计合成了以2-[3-氰基-4-(4-羟基苯基)-5,5-二甲基-5H-呋喃-2-羟基]丙二腈(TCF)为荧光团,碳碳双键为识别位点的探针分子L,通过核磁共振波谱和元素分析对探针的结构进行了表征。利用荧光光谱研究了探针对10种阴离子的识别性能。结果表明,在N,N-二甲基甲酰胺(DMF)/Tris-HCl(8∶2,V/V)缓冲体系中,探针L对S^(2-)具有单一选择性识别作用。荧光滴定光谱及结合比测试表明探针L和S^(2-)以1∶1的方式结合,探针L对S^(2-)的检出限为0.278μmol/L。阴离子竞争实验表明,探针L对S^(2-)的检测具有良好的抗干扰性。核磁氢谱(^(1)H-NMR)滴定实验表明,L与S^(2-)的结合涉及碳碳双键与S^(2-)(HS^(-))的迈克尔加成反应,探针分子的共轭体系减小,从而使探针的荧光由橙黄色变为蓝色。此外,涂有探针L的试纸被成功制作成检测试纸,用于水溶液中S^(2-)的可视化荧光检测。

A novel probe L was designed and synthesized using 2-[3-cyano-4-(4-hydroxyphenyl)-5,5-dimethyl-5H-furan-2-hydroxyl]malononitrile(TCF)as the fluorophore and carbon-carbon double bond as the recognition site.The structure of the probe was characterized by nuclear magnetic resonance spectroscopy and elemental analysis.Fluorescence spectra were used to study the recognition performance of the probe L for 10 anions.The results showed that the probe L had a single selective recognition of S^(2-)in DMF/Tris-HCl(8∶2,V∶V)buffer system.Fluorescence titration spectra and binding ratio tests showed that the probe L and S^(2-)bound in a 1∶1 ratio,and the detection limit of sulfur ion was 0.278μmol/L.The anion competition experiments showed that the probe L had good anti-interference for S^(2-)detection.^(1)H-NMR titration experiments revealed that the binding of L to S^(2-)involved the Michael addition reaction between the carbon-carbon double bond and S^(2-)(HS^(-)),and the conjugated system of the probe decreased,leading to the fluorescence of the probe changed from orange to blue.In addition,the test strip coated with probe L was successfully prepared for the visual detection of S^(2-)in aqueous solution.