A new tripodal chemosensor named PoPAP for colorimetric-enhancing detection of four metal ions from first-row transition series by combining pyridyl and phenolic binding sites with a highly conjugated pyridinyl-1,3,4-oxadiazolyl-phenyl moiety was designed, synthetized, and structurally analyzed. The chemosensor PoPAP is highly water soluble, it gives a selective fast colorimetric response to cations of iron, vanadium, copper and cobalt, depending on pH conditions, and it can discriminate among different oxidation states. PoPAP sensing ability was explored by absorbance spectroscopic studies, “naked-eye” perception, and UV–visible titration. The chemosensor-metal ions binding constants (Ka) and stoichiometry of host-guest complex in aqueous media were determined by classical analytical methods based on UV–visible data. The coordination geometry of PoPAP copper (II) complex was elucidated by crystal structure analysis and used as starting point for ab-initio calculations to analyze the interaction between ligand and metal.

设计，合成并合成了一种新的三脚架化学传感器，称为PoPAP，用于比色法检测第一行过渡系列中的四个金属离子，方法是将吡啶基和酚类结合位点与高度共轭的吡啶基-1,3,4-恶二唑基-苯基部分结合在一起结构分析。化学传感器PoPAP是高度水溶性的，根据pH条件，它对铁，钒，铜和钴的阳离子具有选择性的快速比色响应，并且可以区分不同的氧化态。通过吸收光谱研究，“裸眼”感知和紫外可见滴定来探索PoPAP的感知能力。通过基于紫外可见数据的经典分析方法确定水性介质中客体-客体复合物的化学传感器-金属离子结合常数（Ka）和化学计量。从头算计算来分析配体与金属之间的相互作用。