Tetrazoles and para-Substituted Phenylazo-Coupled Calix[4]arenes as Highly Sensitive Chromogenic Sensors for Ca2+
作者:Yu-Jen Chen、Wen-Sheng Chung
DOI:10.1002/ejoc.200900603
日期:2009.10
Calix[4]arenes 3a (R = OMe) and 3b (R = NO2) with 5,17-bis[4-(4-substituted-phenyl)azo] and 25,27-bisoxymethyltetrazole groups were synthesized by 1,3-dipolar cycloaddition of oxyacetonitrile azocalix[4]arenes 2a and 2b activated with trimethylsilyl azide. UV/Vis screening of 3a and 3b with 14 metal ions showed that 3a (with p-methoxyphenylazo substituent) was a highly chromogenic sensor to Ca2+, whereas
杯[4]芳烃3a (R = OMe)和3b (R = NO2)与5,17-双[4-(4-取代-苯基)偶氮]和25,27-双氧甲基四唑基团通过1,3-合成用三甲基甲硅烷基叠氮化物活化的氧乙腈偶氮杯[4]芳烃2a和2b的偶极环加成。具有 14 个金属离子的 3a 和 3b 的 UV/Vis 筛选表明 3a(带有对甲氧基苯基偶氮取代基)是 Ca2+ 的高度显色传感器,而 3b(带有对硝基苯基偶氮取代基)显示颜色向 Ca2+、Ba2+ 和 Pb2+ 变化。工作区实验揭示了每种复合物的 1:1 结合化学计量。3a·Ca2+、3b·Ca2+、3b·Ba2+ 和3b·Pb2+ 的缔合常数由Benesi-Hildebrand 图确定。根据 1H NMR 滴定结果,Ca2+ 与两个部分去质子化的羟基偶氮酚基团和 3a 和 3b 的两个四唑基团之一结合。