Zor, ErhanSaf, Ahmet OzgurBingol, Haluk2020-03-262020-03-2620131895-1066https://dx.doi.org/10.2478/s11532-012-0192-1https://hdl.handle.net/20.500.12395/29836A novel azocalix[4]arene derivative, 5,11,17,23-tetrakis[(acetophenone)azo]-25,26,27,28-tetrahydroxycalix[4]arene (APC4), containing acetophenone azo groups at the upper rim was synthesized as a chemosensor. Its binding and sensing properties with alkali and alkaline earth metal ions (Li+, Na+, K+, Rb+, Cs+, Mg2+, Ca2+, Sr2+, Ba2+) were investigated by UV-vis spectrophotometric and voltammetric techniques. The stoichiometric ratio and the association constant were determined spectrophotometrically as 1:1 and (1.94 +/- 0.31)x10(5) L mol(-1) for the complex between Mg2+ and the chemosensor, respectively. Moreover, it was shown that the interaction between Mg2+ and the APC4 occurred by means of the phenol groups at the lower rim by voltammetric methods. The results of spectrophotometric and voltammetric experiments showed that the chromogenic chemosensor has high selectivity towards Mg2+ among the other used metal ions, especially the interfering Ca2+ ion.en10.2478/s11532-012-0192-1info:eu-repo/semantics/openAccessChemosensorAzocalix[4]areneMagnesium ionSpectrophotometric methodVoltammetric methodArticle114554560N/AWOS:000313972900010Q3