A highly copper selective chromogenic calix[4]arene derivative

Abstract

In this article, copper selective complexation behavior of 5,11,17,23-tetrakis[(N,N-dicyclohexylamino)methyl]-25,26,27,28-tetrahydroxycalix[4]arene (4) has been explored. Besides this, the binding ability of 4 toward different metal ions such as Cd²⁺, Co²⁺, Cu²⁺, Hg²⁺, Ni²⁺, Pb²⁺ and Zn²⁺ has been investigated by UV-visible and fluorescence spectroscopies. The chromoionophore 4 shows pronounced selectivity for Cu²⁺ even in the presence of other metal ions. The results reveal that Cu²⁺ forms 1 ∶ 1 host–guest complex with 4. The FT-IR spectroscopic method has also been applied for further confirmation of complex formation between 4 and Cu²⁺ and found to be satisfactory.