Heteroatomic substitution of tetraphenylporphyrin as approach for regulating coordination ability

Coordination Properties of Porphyrin Analogues Ionized Forms by Experiment and Quantum Chemistry: 5,10,15,20‐Tetraphenyl‐21‐thia‐ and 5,10,15,20‐Tetraphenyl‐21,23‐Dithiaporphyrins

“…However, the doubly protonated form of ligand I do not demonstrate such properties. In CH 3 CN‐HClO 4 solutions, the reactivity analysis showed that the compound II has very weak basic properties as compared to I and III , partially studied earlier (see, for example, [47] ). However, for all I , II and III compounds, the dissociation processes of the protonated forms represented by equations (S1) and (S2) were observed experimentally, which makes it possible to study and compare their basicity properties.…”

“…[50] The analysis of the UV-Vis spectra showed that as the concentration of HClO 4 in the I-HClO 4 -CH 3 CN system increases, the formation of two groups of isosbestic points was observed, which is due to the presence of two individual equilibria between the pairs of light-absorbing centers, HSPP/H 2 SPP + and H 2 SPP + /H 3 SPP 2 + , see Figure S1 in ESI. [47] A spectrophotometric titration curve, Figure 1(b), and the dependence of logInd vs pH, Figure 1(c, d), based on the experimental data for each ligand protonation stage at different wavelengths confirmed a stepwise interaction of porphyrin I with HClO 4 . Considering (i) the basic dissociation processes of the protonated forms, (ii) equations (S1) and (S2), (iii) material-balance equation (S5) and (iv) the current concentration of all forms (S6) subjected to the Lambert-Bouger-Beer law, the concentration distributions of the molecular and protonated forms for I in the CH 3 CN-HClO 4 system (Figure S1) were expressed by equations S7-S9 in ESI.…”

“…The analysis of the UV‐Vis spectra showed that as the concentration of HClO 4 in the I ‐HClO 4 ‐CH 3 CN system increases, the formation of two groups of isosbestic points was observed, which is due to the presence of two individual equilibria between the pairs of light‐absorbing centers, HSPP/H 2 SPP + and H 2 SPP + /H 3 SPP 2+ , see Figure S1 in ESI [47] . A spectrophotometric titration curve, Figure 1(b), and the dependence of log Ind vs pH, Figure 1(c, d), based on the experimental data for each ligand protonation stage at different wavelengths confirmed a stepwise interaction of porphyrin I with HClO 4 .…”

“…H 2 PP III in organic solvents exhibit amphoteric properties and, in the presence of acids and bases, can be protonated and deprotonated at intracycle nitrogen atoms. In the first approximation (without participation of a solvent and stabilization of the particles formed by counterions), the processes of acid‐base interaction of porphyrins can be described by the equations (S1–S4) in ESI, see also [47] …”

Spectral-Luminescent Properties of the 21-Thia-5,10,15,20-Tetra-(4-Sulfonatophenyl)-Porphyrin: Role of Heterosubstitution and Halochromism

“…В результате замены пиррольного кольца тиофеном либо фураном монозамещенные гетеропорфирины содержат в ядре макроцикла единственный протон, а дважды замещенные -ни одного. По этому их кислотно-основные и координационные свойства существенно отличаются от таковых у собственно порфиринов [6][7][8][9][10][11]. Спектрально-люминесцентные свойства гетеропорфиринов в це лом сохраняют преемственность по отношению к порфиринам, поскольку они являются изоэлектронными (по 26 я-электронов) [6][7][8].…”