Synthesis, Structure and Ion Extraction Properties of Novel Monooxa‐diselkylene‐1,ω‐dioxy Substituted Calix[4]arene Derivatives

Abstract

AbstractNovel macrocyclic monooxa‐diselkylene‐1,ω‐dioxy substituted calix[4]arene derivatives 1a–5a were synthesized by the reaction of calix[4]arene dibromides 1–5 with the disodium salt of bis(2‐selenylethyl)ether in the yields between 28% and 64%. Their structures were characterized by proton and carbon NMR spectra. X‐Ray structure analysis of 1a further confirmed the cone conformation of compounds 1a–5a. An interesting host‐guest complex of 1a with dichloromethane via CH/π and Cl/π interactions was elucidated. Extraction experiments showed that these novel monooxa‐diselkylene‐1,ω‐dioxy substituted calix[4]arene derivatives 1a–5a had strong extraction ability towards mercury ion. The interaction of Hg2+with the calix ligand has also been investigated by 1H NMR titration.