一种席夫碱大环的合成及其与稀土离子的识别研究

Synthesis of a Schiff base macrocyclic and study on recognition for rare-earth ions

采用前体二胺1[间苯二酚-双(4-氨基苯基)醚]和前体二醛2[1,7-二-(2'-甲酰苯基)-1,4,7-三氧庚烷],在Ba2+的诱导作用下,用"一锅煮法"合成得到一种新型的席夫碱大环3,利用1H NMR,13C NMR,IR,质谱等对其进行了结构和组成表征。进一步采用UV-vis光谱技术,对大环3与系列稀土金属离子的键合作用进行考察。结果表明,大环化合物3对铕(III)离子具有选择性识别作用,并进一步测定了大环3与铕(III)离子配位作用的键合比为1∶1,键合常数为1.72×104L·mol-1。

Schiff base macrocycle 3 was synthesized from the reaction of the precusor 1[2-resorcinol-bis（4-aminophenyl）ether]and precursor 2[1,7-bis（2＇-formylphenyl）-1,4,7-trioxaheptance]by“one-pot method”using Ba^2＋ as template. The structures and com-position were characterized by ^1 H NMR,IR,and MS spectra,respectively. The investigation for the reaction of the macrocyclic com-pound 3 with a series of rare earth ions was carried out by UV-vis absorption spectra technique. The results showed that the macro-cycle 3 displayed a selective recognition ability for Eu3＋ion. Further,the JOB plot exhibited the stoichiometric ratio（ host∶guest=1∶1）,the binding constant of the complex was determined,namely K=1. 72 × 10^4L·mol^-1.