Design and synthesis of anthraquinone derived ionophores and their extraction and transport ability for Li+, K+, Ca2+ and Mg2+metal ions

A series of di-substituted anthraquinone i.e. 1,8-bis(2-(2-ethoxyethoxy)ethoxy)anthracene-9,10-dione (I), 1,8-bis(2(2-(2-ethoxyethoxy)ethoxy)ethoxy)anthra- cene-9,10-dione (II) and 1,8-oxybis(ethyleneoxyethylen-eoxy)athraccne-9,10-dione (III) has been synthesized by nucleophilic aromatic substitution on 1,8-dichloroanthra-quinone. These synthetic ionophores were characterized by m.p. determination, elemental analysis, cyclic voltammetric studies, IR, NMR, and mass spectral analysis. These ionophores have been used in oxidized and reduced state for extraction and bulk liquid membrane transport studies of Li+, K+, Ca2+ and Mg2+ metal cations. The results reveal that these ionophores are good extractants not only when reduced but in its neutral form as well. Transport ability of these ionophores was enhanced in their reduced state. Ionophore I is good extractant for K+. Ionophores II is good carrier for all metals, those have been studied. Ionophore III shows high selectivity toward Ca2+ which can be used for the fabrication of ion selective electrodes and sensors.