Investigation of [MSalen/salophen] (M = Cr3+, Fe3+ or Co3+) capped dinuclear complexes of two novel tetraoxocalix[2](m-hydroxymethyl)arene[2]triazine compounds

Abstract

In this work, (3,5-bis((4,6-dichloro-1,3,5-triazine-2-yl)oxy)phenyl)methanol was obtained by reacting cyanuric chloride with 3,5-dihydroxybenzyl alcohol at 0 °C. Then, s-triazine bridged calixarene codded as L1 was obtained by reacting the compounds with 3,5-dihydroxybenzyl alcohol. Targed ligands, which we code as L2 and L3, were obtained from the reaction of the L1 coded compound with 4-aminobenzoic acid or 4-hydroxybenzoic acid, respectively. [MSalen/Saloph] capped s-triazine bridged calixarene complexes were obtained from the reaction of the L2 or L3 codded ligand and the [(MSalen/Saloph)₂O] (M = Cr³⁺, Fe³⁺, Co³⁺) starting complexes in 1,4-dioxane media. The ligands and complexes were characterized by using ¹H-NMR, FT-IR spectroscopy, UV-Vis spectroscopies, magnetic susceptibility, TGA-DTA and elemental analysis techniques. Metal contents of the complexes were determined by using ICP-AES spectroscopy. Calixarenes can be used in many areas such as chiral phase transfer catalyst, recognition of enantiomers, stationary phase in chromatography, recovery of heavy and precious metals molecules or ions from environmental wastes. Graphical Abstract