Cation assisted complexation of octacarbazolylphenyl substituted Zn(ii)-tetraphenylporphyrin with [2,2,2]cryptand

Abstract

Supramolecular complex formed from a carbazolylphenyl-porphyrin first generation dendrimer and [2,2,2]cryptand was prepared and investigated the influence of alkali metal cations on its formation and properties.

Molecular Recognition of Imidazole Derivatives by Co(III)-Porphyrins in Phosphate Buffer (pH = 7.4) and Cetylpyridinium Chloride Containing Solutions

“…In the reports [ 13 , 14 , 15 , 16 , 17 ], devoted to the formation of supramolecular porphyrin complexes with several binding points, the contributions of axial coordination energy (Δ G axial coord. ) and H-bonds (Δ G HB ) to the total energy of the complex formation were estimated.…”

“…[ 6 , 7 , 8 , 9 , 10 ], depending on the nature of the central metal cation. The most metalloporphyrin receptors described in the literature are hydrophobic Zn(II)-porphyrins [ 11 , 12 , 13 , 14 , 15 , 16 , 17 ], which form supramolecular complexes with substrates in the organic media (dichloromethane, chloroform, benzene, or toluene). Hydrophilic Co(III)-porphyrins are characterized by a high binding ability towards various nitrogen-containing biomolecules in aqueous, biological media [ 18 , 19 , 20 , 21 ].…”

Macrocyclic Receptors for Identification and Selective Binding of Substrates of Different Nature

“…The cryptand nitrogen atoms and the porphyrinate metal cation act in this case as the binding centers. The authors of [ 110 ] studied the formation of a complex between zinc porphyrinate 82 and cryptand-2,2,2 (Cr1) as a model system. It is shown that the electronic absorption spectra of the reaction system have one family of spectral curves with its own set of isobesticpoints ( Figure 24 a).…”

“…The structure of the receptor-substrate complex was verified by the 2D ROESY NMR method. It should be said that a lot of works describe the binding ability of macrocyclic receptors with well-defined geometries [105][106][107][108][109][110][111]. An analysis of the presented data indicates that their complexing ability is strongly dependent on the conformational mobility of the lateral substituents (molecular fragments) and the possibility of formation of intramolecular cavities and channels of various shapes within them.…”

“…The authors of [110] investigated the complex formation between carbazolyl-substituted zinc porphyrinates with first- (79) and second-generation (82) lateral branches and cryptands that are significantly different in their geometric and complexing parameters and the effect of alkali metal cations on this process. Cryptands are well known to be able to act as receptors of alkali metal cations.…”