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A new family of hyperbranched molecules and dendrimers has been constructed from a diamide–dicalix derivative prepared from monocarbomethoxymethyl p-tert-butyl calix[4]arene and tris(2-aminoethyl)amine (‘tren’) via amide-formation reactions. The selective 1,3-di-O-functionalization of p-tert-butyl calix[4]arene moieties allows the synthesis of first- (G1) and second-generation (G2) calix-dendrimers. Replacement of the quadridentate amine by a trithia-ether-triamine-mono-ol, ’hyten’, again results in acylation of the amino groups, but with the generation of a central cavity with different complexing properties. A new family of hyperbranched molecules and dendrimers has been constructed from a diamide–dicalix derivative prepared from monocarbomethoxymethyl p-tert-butyl calix[4]arene and tris(2-aminoethyl)amine (‘tren’) via amide-formation reactions. The selective 1,3-di-O-functionalization of p-tert-butyl calix[4]arene moieties allows the synthesis of first- (G1) and second-generation (G2) calix-dendrimers

Complex formation of five teraamido-type calix [4] arene derivatives—containing a heteroaromatic ring on the carboxamide moieties forming the coordination sphere—with alkali/alkali earth ions were the subject of FT–IR studies. The selectivity of these ligands toward different cations were found in acetonitrile solution, with the best detection in the case of the thiophene derivative, ligand 3, that exhibited selectivity to thallium(I) and thallium(III) ions over alkali/alkaline earth ions. Calixarenes 2 and 4 exhibit selectivity to potassium and ligand 5 to lithium ions among alkali/alkaline earth ions, however, thallium(I) ions show interference with these measurements. Moreover, selectivity was observed in solid state when surface complexes were prepared on sodium chloride, potassium chloride, bromide and iodide, calcium chloride and fluoride. The solid samples were examined by FT–Raman and Diffuse Reflectance Infrared Fourier Transform Spectroscopy (DRIFTS) method. Calixarenes 2 and 4 are of potential ...

Reactions between a tripodal trithiaether-triamine and the monomethoxycarbonylmethyl ether of p-tert-butylcalix[4]arene led to the ready isolation of both di- and triamides, namely di- and tricalixaryl derivatives of the tripod. These molecules, designed as dendrimer precursors, retain a core capable of acting as a multidentate ligand for metal ions. Studies of complex formation with Zn(II) and Co(III) by these new ligands show that indeed there is preferential binding to the core (rather than to the phenolic sites of the calixarene units), suggesting new mechanisms for the control of the structure and stereochemistry of dendrimer species.