Two novel fluorescent calix[4]arene derivatives la and lb with benzoxazole or benzothiazole units in 1,3-alternate conformation have been synthesized and characterized by IR, ^1H NMR, ^13C NMR and MS. Their complexation properties to different heavy and transition metal ions have been studied by UV-vis spectroscopy and fluorescence spectrometer. Compounds 1a and 1b show selective recognition to Fe^3＋ and Cr^3＋.
Four novel calix[4]arene derivatives 5-8 bearing four fluorogenic coumarin units attached via imino group acting also as binding sites at the upper rim have been prepared and characterized by IR, IH NMR and MS. Compounds 5-8 adopt a cone conformation. Their complexation properties to different heavy and transition metal ions have been studied by UV-vis spectroscopy. Compounds 5, 6, 8 show selective recognition to Fe^3＋ and Cr^3＋.
