Showing papers by "N. Zh. Mamardashvili published in 2011"
TL;DR: In this article, the saturated vapor pressures of several macrocyclic compounds were determined for the first time using Knudsen's effusion method over a wide temperature range and the sublimation thermodynamics were calculated for the studied compounds.
7 citations
TL;DR: In this paper, the acidity properties of meso-aza-substituted porphyrins in the system of dimethyl sulfoxide-potassium cryptates (DMSO-K[222]OH) at ambient temperature were investigated by the method of spectrophotometric titration.
Abstract: Acidic properties of 10,20-diaza-3,7,13,17-tetramethyl-2,8,12,18-tetra-n-hexylporphyrin, 2,7,12,17-tetra-t-butyltetrabenzo-5,10,15-triazaporphyrin and octa(n-amyloxy)phthalocyanine in the system of dimethyl sulfoxide-potassium cryptates (DMSO-K[222]OH) at ambient temperature was investigated by the method of spectrophotometric titration. The porphyrins in the DMSO-K[222]OH medium were shown to dissociate sequentially forming mono- and dianions in two steps. The concentration ranges of existence of the anionic forms and the acidity sequence of the studied meso-aza-substituted porphyrins were investigated.
4 citations
TL;DR: Zinc calix[4]arene-bis(porphyrinate) with two ethoxycarbonyl substituents at the lower rim of the calix [4] arene moiety was synthesized in this article.
Abstract: Zinc calix[4]arene-bis(porphyrinate) with two ethoxycarbonyl substituents at the lower rim of the calix[4]arene moiety was synthesized. Its complexation properties toward the sodium cation and triethylenediamine were studied. The influence of the binding of the sodium cation by the calix[4]arene moiety on the complexation properties of the interporphyrin cavity toward triethylenediamine was revealed.
3 citations
TL;DR: The complexation properties of zinc 10,20-bis [5-(2,3,7,8,12,13,17,18-octaethylporphyrinate)ethynylphenyl]-5,5′,10′,15,15′,20′-hexamethylcalix[4]pyrrole toward halide ions, triethylenediamine, and 4,4′-bipyridyl were studied by spectrophotometric titration and 1H NMR spectroscopy.
Abstract: The complexation properties of zinc 10,20-bis[5-(2,3,7,8,12,13,17,18-octaethylporphyrinate)ethynylphenyl]-5,5′,10′,15,15′,20′-hexamethylcalix[4]pyrrole toward halide ions, triethylenediamine, and 4,4′-bipyridyl were studied by spectrophotometric titration and 1H NMR spectroscopy. The influence of binding of anions (F− and Cl−) by the calix[4]pyrrole fragment of zinc calixpyrrole-bisporphyrinate on the complexation properties of its interporphyrin cavity toward the bidentate organic ligand triethylenediamine.
3 citations
TL;DR: In this paper, the bisporphyrin-calixarene crown ethers with the amino and hydroxy groups in tetrapyrrole fragments and polyethyleneoxide complexing cavity in the calix[4]arene fragment of the macrocycle were investigated.
Abstract: In order to create heterotopic receptors of polyfunctional substrates we have synthesized the bisporphyrin-calix[4]arene crown ethers [6] with the amino and hydroxy groups in tetrapyrrole fragments and polyethyleneoxide complexing cavity in the calix[4]arene fragment of the macrocycle. Their spectral properties and complexing ability toward the alkali metal cations, organic diamines, and dicarboxylic acid esters were investigated.
3 citations
TL;DR: In this article, the influence of tetrapyrrole macrocycle on the reactivity of Zn2+ porphyrins toward palladium chloride in boiling DMF was established.
Abstract: Transmetallation of zinc (Zn2+) and cadmium (Cd2+) complexes of 5,10,15,20-tetraphenylporphin, 5,10,15,20-tetra(4-chlorophenyl)porphyrin, 5,10,15,20-tetra(4-methoxyphenyl)porphyrin, tetrabenzoporphyrin, and octaphenyltetraazaporphyrin with PdCl2 in DMF was studied by spectrophotometry. The influence of the nature of the tetrapyrrole macrocycle on the reactivity of Zn2+ porphyrins toward palladium chloride in boiling DMF was established. Palladium(II) complexes of 5,10,15,20-tetraphenylporphyrin, 5,10,15,20-tetra(4-chlorophenyl)porphyrin, 5,10,15,20-tetra(4-methoxyphenylporphyrin), and tetrabenzoporphyrin were prepared and identified.
2 citations
TL;DR: In this article, the formation and thermal destruction of a complex with n-hexane were revealed by combined analysis of powder X-ray pictures and data obtained by differential scanning calorimetry.
Abstract: Complex polymorphic conversions of 4-tert-butylcalix[4]arene upon the formation and thermal destruction of a complex with n-hexane were revealed by combined analysis of powder X-ray pictures and data obtained by differential scanning calorimetry.
2 citations
TL;DR: In this article, the metal exchange reactions between cadmium meso-triaza-β-tetra-(4-tert-butylbenzo)porphyrinate (Cd-3N(t-BuBz)P) and copper and zinc chlorides in dimethyl sulfoxide were studied by spectrophotometry.
Abstract: The metal exchange reactions between cadmium meso-triaza-β-tetra-(4-tert-butylbenzo)porphyrinate (Cd-3N(t-BuBz)P) and copper and zinc chlorides in dimethyl sulfoxide were studied by spectrophotometry. The kinetic and energy parameter of the reactions were determined. The results of the metal exchange reaction were compared with those for the reactions of formation Zn-3N(t-BuBz)P and Cu-3N(t-BuBz)P, which were obtained by the interaction of meso-triaza-β-tetra-(4-tert-butylbenzo)porphine (H2-3N(t-BuBz)P) with the corresponding d-metal cations.
1 citations
TL;DR: In this article, the 5,10,15,20-tetraphenyl-2,3,7,8,12,13,17,18,21,22,23,24-dodecamethylporphyrin ditriflate was synthesized and its complexing properties toward fluoride ion were investigated by spectrophotometric titration.
Abstract: The 5,10,15,20-tetraphenyl-2,3,7,8,12,13,17,18,21,22,23,24-dodecamethylporphyrin ditriflate was synthesized and its complexing properties toward fluoride ion were investigated by spectrophotometric titration in the acetonitrile-tetrabutylammonium fluoride system. We found that at the complexation the two triflate counterions are replaced by the fluoride ions. The stability constants of the complexes and the concentration ranges of their existence were determined.
TL;DR: In this paper, the main properties of 5,10,15,20-tetra(4-chlorophenyl)porphyrin in the acetonitrile-perchloric acid system were studied by the method of spectrophotometric titration at standard temperature.
Abstract: Main properties of 5,10,15,20-tetra(4-chlorophenyl)porphyrin in the acetonitrile-perchloric acid system were studied by the method of spectrophotometric titration at standard temperature. The protonation of nitrogen atoms of the tetrapyrrole macrocycle was shown to occur in two steps, through the formation of mono- and diprotonated forms. The corresponding ionization constants and concentration intervals were determined. The diprotonated form of porphyrin was shown to bind effectively iodide, bromide and chloride ions, the stability constants of the complexes of 1:1 and 1:2 composition were determined.
TL;DR: In this paper, the receptor properties of complexes of 5,10,15,20-tetraphenyl-21,22,23-trimethylporphyrin and 5, 10, 15,20 -tetrameryl-2,3,7,8,12,13,17,18,21, 22,23,24-dodecamethylpyrin toward hydroxide ion were explored by the method of spectrophotometric titration in methanol with iodine and triflate respectively.
Abstract: The receptor properties of complexes of 5,10,15,20-tetraphenyl-21,22,23-trimethylporphyrin and 5,10,15,20-tetraphenyl-2,3,7,8,12,13,17,18,21,22,23,24-dodecamethylporphyrin toward hydroxide ion were explored by the method of spectrophotometric titration in methanol with iodine and triflate respectively. We found that in the studied complexes the hydroxide ion is replaced by the respective counterion that leads to a strong response in the visible region of absorption spectrum. The formation constants and the concentration ranges of existence of the complexes were determined.