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Calixarenes have been widely regarded as an important class of macrocyclic host molecules, due to their efficient and highly selective binding properties towards specific metal ions. Azocalixarenes, containing single conjugated chromophore azo (‒N˭N‒) group in p- positions are synthesized by “one-pot” procedures with satisfactory yields. Their structures (as solid and liquid) are elucidated by UV-Vis, FT-IR, 1H and 13C-NMR spectroscopic methods, as well as elemental analysis techniques. Thermal stability of calixarenes is very important because of their potential applications in high temperature processes such as the dyeing of textile fibers, ink-jet printing and photocopying and in high technology areas such as lasers and electro-optical devices. In this paper all the thermal studies of parent calix[n]arenes, azocalix[4]arene derivatives and their complexes containing lower and upper rim functionalized groups are reported. All the thermo analytical results such as the temperature ranges and peak temperat...

In the present study, thermal decomposition of mono- and di-azocalix[4]arene derivatives (A1–A8 and B1–B8) was investigated by means of thermogravimetry (TG), differential thermal analysis (DTA) and derivative thermogravimetry (DTG). The exclusion of methanol, hydrolysis of benzoyl ester and methyl ketone groups in lower rim, and decomposition of azo groups in upper rim have occurred during thermal analysis, consecutively. The thermal decomposition degrees amount of volatile pyrolysis products were determined in air atmosphere using TG, DTA and DTG curves. In conclusion, the thermal analyses of azocalix[4]arenes demonstrated that its stability depends on the substituted groups and their positions in the calix[4]arene structure.

In this study, six new calix[n]arene-Fe3+ complexes (n?=?4,?6,?8) were synthesized with parent calix[n]arenes in a DMF solution of FeCl3?•?H2O. The properties and coordination characteristics of the six parent calix[n]arene-Fe3+ complexes were determined by elemental analyses, TG-DTA, UV-vis, FT-IR and 1H NMR spectroscopy. According to UV-vis analysis, in the six complexes the iron(III) coordinated by oxygen donor atoms from calix[n]arene ligands and DMF molecules. The complexes behave as 1?:?1 and 1?:?2 electrolytes in the case of calix[n]arenes (n?=?4,?6) (1-4) and calix[8]arene (5, 6), respectively. 1H NMR studies demonstrate that 1 and 2 are more stable than 3, 4, 5 and 6 in DMF, and indicate cone conformation of the calix[4]arene ligands (1 and 2).

[Cu(pydc)(im)]n (1), [Cu(pydc)(mim)3]∙2H2O (2), [Cu(pydc)(ampy)(H2O)]∙H2O (3), and [Cu(pydc)(phen)][Cu(Hpydc)2] (4) (H2pydc = 2,6-pyridinedicarboxylic acid or dipicolinic acid, im = imidazole, mim = 2-methylimidazole, ampy = 2-amino-4-methylpyridine, and phen = 1,10-phenanthroline) were synthesized and characterized by elemental analysis, spectroscopic measurements (UV–vis and IR spectra) and single crystal X-ray diffraction. Complexes 1, 2 and 3 were studied by thermogravimetric analysis from ambient temperature to 1100 K under nitrogen and thermal stabilities were investigated. The effects of complexes on proliferation of fibrosarcoma cells were investigated using the Quick Cell Proliferation Assay. The cell viability changes depend on the concentrations and type of complexes. According to cell proliferation/viability data, 4 was determined to be the most cytotoxic.

[Cu(pydc)(im)]n (1), [Cu(pydc)(mim)3]∙2H2O (2), [Cu(pydc)(ampy)(H2O)]∙H2O (3) and [Cu(pydc)(phen)][Cu(Hpydc)2] (4) (H2pydc = 2,6-pyridinedicarboxylic acid or dipicolinic acid, im = imidazole, mim = 2-methylimidazole, ampy = 2-amino-4-methylpyridine and phen = 1,10-phenanthroline) were synthesized and characterized by elemental analysis, spectroscopic measurements (UV-vis and IR spectra) and single crystal X-ray diffraction. Complexes 1, 2 and 3 were studied by thermogravimetric analysis from ambient temperature to 1100 K under nitrogen and thermal stabilities were investigated. The effects of complexes on proliferation of fibrosarcoma cells were investigated using the Quick Cell Proliferation Assay. The cell viability changes depend on the concentrations and type of complexes. According to cell proliferation/viability data, 4 was determined to be the most cytotoxic.