Synthesis of New Substituted Calix[4]Arenes and Their Complexes with Iron(III)

Abstract

Abstract The synthesis of new substituted calix[4]arenes was investigated to increase their solubility in organic solvents. It was observed that these compounds cannot be prepared from phenols substituted with strong electron withdrawing substi-tuents (e.g., -CN, -NO2) and phenols which have a p-acidic group (e.g., -OH, -COOH), or a p-carboxylate group (e.g., -COONa). These compounds were treated with some transition metal salts (e.g., FeCl3.6H20, CuCl2.2H20, NiCl2.6H20 or CoCl2.6H20). But only Fe(III) gave complexes with the compounds and the complexes have a metal-ligand ratio of 1:1. Elemental analyses, 1H-NMR and IR data of the new compounds are given. It was concluded that these compounds can be used as organic precipitating reactive for iron(III).