Cation Recognition And Synthesis Of Calix[4]arene Receptors Containing Heteroatoms

A study on extracting cations of a series of calix[4]arene derivatives bearing a wide range of functional groups which include some heteroatoms such sulphur, selenium and tellurium, and ferrocenyl was performed. Factors which affect results of extraction were emphatically discussed. We analysed and studied many factors which include matching degree of hard and soft acid and base between heteroatoms and metal cations, matching degree of dimensioncan between cavums of receptors and metal cations, degrees of flexibility of receptors and functions of substituting, groups etc. influence abilities of calix[4]arene receptors to coordinate and recognize metal cations. Through the studies, we profoundly comprehended these calix[4]arene receptors' capabilities in recognising metal cations. The studies indicate that these receptors have feeble abilities to recognize alkali and alkaline earth metal cations at large and have relatively strong abilities to recognize transitional and heavy metal cations, especially Hg2+ and Ag+ as soft acid. In addition, based on previous synthesis, some kinds of tweezers-like calix[4]arene receptors containing 9-anthrysulfur and 9-anthryselenium have been designed and synthesized in over 60% yields. That testifies that this synthesis is still feasible to synthesize bisanthryl calix[4]arenas, and provides material foundation for the further study on light capability and fluorescent recognition of metal cations calixarenes containing functional groups of anthracene. At present, these studies are being in progress.