A new calix[4]azacrown ether based boradiazaindacene (Bodipy): Selective fluorescence changes towards trivalent lanthanide ions

We report on the synthesis and photophysical properties of a new calix[4]azacrown derivative, capped with two amide bridges, in the cone conformation bearing two boradiazaindacene (Bodipy) groups at the narrow rim. Its binding properties towards trivalent lanthanide ions such as La 3+, Gd3+, Tb3+, Dy3+, Er 3+ and Yb3+ were investigated by using spectroscopic techniques. With respect to fluorescence intensity changes upon trivalent lanthanide ion complexation, calix[4]azacrown ether based Bodipy showed higher selectivity towards Yb3+ ion over other ions. Presence of proximal two amide groups in calix[4]azacrown ether based Bodipy were observed to play an important role in exhibiting its lanthanide ion binding. © 2013 Elsevier B.V. All rights reserved.