A Calix[4]imidazolium[2]pyridine as an Anion Receptor

摘要

The design and synthesis of efficient receptors capable of binding biologically and environmentally important anionic species is an emerging field in supramolecular chemistry.Anion receptors with amide,pyrrole,urea,ammonium,and guanidinium groups as binding sites form N-H...A~- hydrogen bonds.In contrast,we have studied several benzene- and anthracene-based receptors with two or three imidazolium units which bind effectively with anionic species through (C- H)~+...A~- hydrogen-bonding interactions.The discovery of calix[4]pyrroles as anion receptors has led to detailed studies and further synthetic modifications being carried out for use in a range of applications,including anion sensing and transport.