N-(2,4-二硝基苯基)-N -取代苯腙衍生物对阴离子识别研究

Abstract

[中文文摘]合成了4种N-(2,4-二硝基苯基)-N'-取代苯腙类阴离子结合受体(1～4,取代基R=H,o-OCH3,o-Cl,o-OH),应用紫外吸收光谱方法研究了其与阴离子的相互作用,以及考察N'-苯环取代基对受体分子之阴离子亲合力和选择性的影响.实验显示:乙腈中F-、CH3CO-2等阴离子使受体分子吸收光谱红移,溶液由黄色转变为红色,其中受体分子2对F-表现出高选择性的灵敏响应.实验表明受体-阴离子间形成了氢键型超分子配合物,Job作图法给出了受体分子与阴离子的1∶1结合计量比,1H NMR滴定为受体分子与阴离子间的氢键作用本质提供了直接证据.[英文文摘]Four N-(2,4-dinitrophenyl)-N -(substituted-phenyl)hydrazones(substituent R=H,o-OCH3,o-Cl and o-OH) were synthesized as absorption spectral chemosensors for receptors.The binding properties of these receptors with anions such as F-and AcO-in CH3CN were investigated by UV-visible absorption spectroscopy.Results showed that a distinct color change occurred from yellow to light yellow upon addi-tion of F-and AcO-.Substituent was found to exert influence on the spectral response sensitivity and se-lectivity,with receptor 2 bearing an o-OCH3 substituent showing the highest selectivity and good sensitivity for F－. Job plots indicated a 1∶1 anion binding stoichiometry of the receptors, for which a hydrogen bonding interaction was identified from the 1H NMR titrations and the effect of competitive solvent MeOH on anion binding. As a distinct solution color change occurs it is possible to detect anions such as fluoride by naked eyes.