N. Zh. Mamardashvili

Synthesis and basic properties of bisporphyrinocalix[4]arene

A bisporphyrinocalix[4]arene was prepared, and its basicity was examined spectrophotometrically. The protonation of tetrapyrrole fragments of the porphyrinocalixarene conjugate in the ethanol-sulfuric acid system occurs in two steps and is described by the Hammett equation. The ionization constants and the concentration intervals of the formation of the mono-and dicationic forms of the bisporphyrinocalixarene were determined.

Porphyrin halide ion receptor

Formation of 1:1 and 1:2 complexes of mono-and dications of octaalkylporphyrin with halide ions in acetonitrile at 298 K was studied by spectropotentiometric titration. The stability constants of the complexes were determined.

Calix[4]arene-porphyrin molecular receptors for selective binding of ethylenediamines

A new zinc calix[4]arene-bis-porphyrinate was synthesized and its 1 : 1 and 1 : 2 complexation reaction with ehtylenediamine, diethylenediamine, and triethylenediamine in toluene at 298 K was studied by spectrophotometric titration and 1H NMR.

Synthesis and spectral properties of cobalt(II) and cobalt(III) tetraarylporphyrinates

Reactions of 5,10,15,20-tetraphenylporphin, 5,10,15,20-tetra(4′-methoxyphenyl)porphyrin, and 5,10,15,20-tetra(4′-chlorophenyl)porphyrin with cobalt(II) acetate in dimethylformamide were studied by spectrophotometry. The corresponding cobalt(II) porphyrinates were synthesized and identified. The corresponding cobalt porphyrinates in +3 oxidation state were obtained by reaction of cobalt(II) 5,10,15,20-tetraphenylporphyrinate and cobalt(II) 5,10,15,20-tetra(4′-methoxyphenyl)porphyrinate with 2,3-dichloro-5,6-dicyano-p-benzoquinone in chloroform. The oxidation of cobalt(II) 5,10,15,20-tetra(4′-chlorophenyl)porphyrinate with hydrochloric acid in dimethylformamide leads to cobalt(III) porphyrinate.

Complexation of zinc octaalkylporphyrin with mono-, di-, and triethylenediamines in toluene

The complexation of zinc octaalkylporphyrin with mono-, di-, and triethylenediamines in toluene was studied by spectrophotometry using the molar ratio method and by 1H NMR. The effect of the structure of the two-center organic base on the formation of 1 : 1 or 2 : 1 metal porphyrin-ligand complex was established. The stability constants of the resulting complexes were calculated and the concentration ranges of their existence were determined.

Pyridyl-substituted porphyrins: II. Synthesis and basic properties of dipyridylporphyrins

Abstract5,15-Bis(pyridin-2-yl)-, 5,15-bis(pyridin-3-yl)-, and 5,15-bis(pyridin-4-yl)-substituted 3,7,13,17-tetramethyl-2,8,12,18-tetraethylporphyrins were synthesized, and their acid-base properties in ethanol-sulfuric acid were studied by spectrophotometric titration. Concentration ranges for the existence of mono- and dicationic forms of 5,15-dipyridylporphyrins and the corresponding ionization constants were determined. The effect of pyridine fragments on the basic properties of alkyl-substituted porphyrins was discussed.

Pyridyl-substituted porphyrins: I. Synthesis and basicity of monopyridylporphyrins

Abstract13,17-Diethyl-2,3,7,8,12,18-hexamethyl-5-(pyridin-2-yl)porphyrin, 13,17-diethyl-2,3,7,8,12,18-hexamethyl-5-(pyridin-2-yl)porphyrin, and 13, 17-diethyl-2,3,7,8,12,18-hexamethyl-5-(pyridin-4-yl)porphyrin were synthesized, and their basic properties were studied by spectrophotometric titration in the system ethanol-sulfuric acid. Concentration ranges for the existence of mono- and dicationic forms of meso-pyridyl-substituted porphyrins and the corresponding ionization constants were determined.

The effect of the structure of aliphatic diamines on their interaction with zinc porphyrinates

The complex formation of zinc 2,8,12,18-tetramethyl-3,7,13,17-tetraethylporphyrinate, 5,17-bis(zinc 2,8,12,18-tetramethyl-3,7,13,17-tetraethyl-10-phenylporphyrinate)-25,27-dimethoxy-26,28-dihydroxycalic-[4]-arene, and 5,17-bis(zinc 2,8,12,18-tetramethyl-3,7,13,17-tetraethyl-10-phenylporphyrinate)-25,27-dimethoxy-26,28-crwon-[6]-calix-[4]-arene with 1,2-diaminoethane, 1,3-diaminopropane, and 1,2-di-(dimethylamino)ethane in toluene was studied by spectrophotometric molar ratio method and 1H NMR. The effect of the diamine structure on the formation of “internal” and “external” porphyrinate-ligand complexes of the composition 1 :1 and 1 :2 was established. The stability constants of the complexes obtained were calculated and the concentration intervals of their formation were determined.

Complexation of Zn Arylporphyrinates with Leucine Methyl Ester

Extra coordination of L-leucine methyl ester with seventeen different Zn arylporphyrinates is studied by spectrophotometric titration and capability of Zn porphyrinates with the active OH groups to recognize LeiOCH3 in toluene at 20°C is determined. The formation of associates of the composition amino acid ether–porphyrinate depending on the substituent positions in a macrocycle is studied by the 1H NMR method. The most strong donor–acceptor bonds between Zn porphyrinate and LeiOCH3 are observed in the case of pyridine-substituted porphyrins and porphyrins with phenyl rings containing electron-donor substituents in the m-position. The best recognizing capabilities with respect to leucine are shown by Zn porphyrinates with di- and tetra-4-OH-phenyl substitution in the meso-positions of a macrocycle.

Influence of substituents structure and their electronic effects on acid-base and complexing properties of 5,10,15,20-tetranitro-2,3,7,8,12,13,17,18-octaethylporphyrin

Abstract5,10,15,20-Tetranitro-2,3,7,8,12,13,17,18-octaethylporphyrin has been prepared, and its acid-basic properties have been studied in acetonitrile by titration with 1,8-diazabicyclo [5.4.0]undec-7-ene and perchloric acid. The substituted porphyrin ability towards complex formation with zinc acetate has been studied in acetonitrile and acetonitrile, 1,8-diazabicyclo [5.4.0]undec-7-ene media. Spectral properties of neutral and ionic forms of 5,10,15,20-tetranitro-2,3,7,8,12,13,17,18-octaethylporphyrin and its zinc complex have been determined; constants of acid and basic ionization of the ligand have been estimated. Kinetic parameters of the porphyrin complex formation with zinc via molecular and ionic mechanism have been analyzed. The substituents effect on the studied properties is discussed.