喹啉类主体分子的设计合成与阴离子识别

Design and Synthesis of Anion Receptors Based on Azoquinoline and Their Anion Recognition

合成了系列 5 ( 8 羟基喹啉 )偶氮苯衍生物 ,研究了取代基对其吸收光谱的影响 ,比较了不同主体化合物对阴离子亲合能力的差异 .研究结果表明 :5 ( 8 羟基喹啉 )偶氮 4′ 甲基苯对F-具有选择性识别作用 ,主客体分子间形成 1∶1型阴离子配合物 ,其最大吸收波长为 5 0 8nm ,溶液颜色由无色变为红色 ,配合物的稳定常数为 2 5× 10 4mol-1·L .其它阴离子如AcO-,H2 PO-4,HSO-4,ClO-4,Cl-和Br-等均不影响主体与F-的显色反应 ,据此建立了选择性识别氟离子新体系 .

A series of 8-hydroxyl-5-(4-substituted phenylazo) quinoline derivatives were designed and synthesized. The interactions between receptors and anions such as F-, AcO-, H2PO4-, Cl- and Br- in acetonitrile were investigated by UV-vis spectroscopy. Results indicated that hydrogen-bonding complexes were formed between receptors and anions, which induced remarkable color change. It was found that the selectivity of receptors to anion could be efficiently tuned by substitution at the phenyl moiety. Receptor 1, 8-hydroxyl-5-(4-methylphenylazo) quinoline, was capable of selectively binding fluoride anion over other anions. A 1 : 1 model complex was formed between 1 and fluoride, the solution of 1 turned red from colorless and a new absorption band peaked at 508 nm appeared. The association constant of 1-F- complex was 2.5 x 10(4) mol(-1) . L. However, no obvious color changes were observed on addition of equivalent of other anions such as AcO-, H2PO4-, Cl- and Br-. A selective colorimetric assay for fluoride was developed.