Bis(azobenzocrown ether)s—synthesis and ionophoric properties

Novel biscrowns were successfully synthesized from azobenzocrown ethers containing hydroxyl groups in para position relative to the azo group. The synthesized host molecules, differing in the size of the macrocycles, the length of the linker and their potential to act as sodium or potassium ionophores, were characterized and used as ionophores in classic and miniature (screen-printed) ion-selective electrodes. Metal cation complexation for selected macrocycles was carried out with the use of UV–vis spectroscopy in acetonitrile. The structural features of novel complex have been deduced by X-ray crystallography. X-ray analysis indicated the formation of sandwich structures with two sodium cations encapsulated between two macrocyclic molecules of 13C2.