Kinetic stability of corrole complexes with manganese, copper, and zinc in environments based on acetic and sulfuric acids

Berezin, D. B.; Shukhto, O. V.; Thao, Vu Thi; Karimov, D. R.; Berezin, B. D.

doi:10.1134/s0036023614120067

Cited by 9 publications

(7 citation statements)

References 12 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The rapid degradation of the metallocorroles observed in our experiments and the well‐known metalation and demetallation of metallocorroles and other macrocycles provide experimental evidence for such full protonation of the inner core N atoms in our system. The reaction corrole+metal 3+ →metallocorrole+3H + is known to shift to the left in highly acidic environments; [36–38] a similar effect has also been observed for phthalocyanines [39,40] . The fully protonated metallocorolle is likely to be an intermediate state in this reaction and will be obtained during the demetallation process.…”

Section: Resultsmentioning

confidence: 68%

Control of Molecular Catalysts for Oxygen Reduction by Variation of pH and Functional Groups

et al. 2021

View full text Add to dashboard Cite

In the search for replacement of the platinum‐based catalysts for fuel cells, MN4 molecular catalysts based on abundant transition metals play a crucial role in modeling and investigation of the influence of the environment near the active site in platinum‐group metal‐free (PGM‐free) oxygen reduction reaction (ORR) catalysts. To understand how the ORR activity of molecular catalysts can be controlled by the active site structure through modification by the pH and substituent functional groups, the change of the ORR onset potential and the electron number in a broad pH range was examined for three different metallocorroles. Experiments revealed a switch between two different ORR mechanisms and a change from 2e− to 4e− pathway in the pH range of 3.5‐6. This phenomenon was shown by density functional theory (DFT) calculations to be related to the protonation of the nitrogen atoms and carboxylic acid groups on the corroles indicated by the pKa values of the protonation sites in the vicinity of the ORR active sites. Control of the electron‐withdrawing nature of these groups characterized by the pKa values could switch the ORR from the H+ to e− rate‐determining step mechanisms and from 2e− to 4e− ORR pathways and also controlled the durability of the corrole catalysts. The results suggest that protonation of the nitrogen atoms plays a vital role in both the ORR activity and durability for these materials and that pKa of the N atoms at the active sites can be used as a descriptor for the design of high‐performance, durable PGM‐free catalysts.

show abstract

Section: Resultsmentioning

confidence: 68%

Control of Molecular Catalysts for Oxygen Reduction by Variation of pH and Functional Groups

et al. 2021

View full text Add to dashboard Cite

show abstract

“…Thus, the kinetic equation of reaction (1) has the form (6) Based on the experimental data on the metal exchange of CdP with ZnCl 2 in DMSO (Table 1, Fig. 1), we may assume that reaction (1) proceeds, in this case, via the associative mechanism [8,19]. Prob ably, an intermediate is rapidly formed in the first step of the process.…”

Section: Resultsmentioning

confidence: 99%

Metal exchange reaction of cadmium 5-monoaza-2,3,7,8,12,13,17,18-octamethylporphyrinate with zinc(II) and copper(II) chlorides in dimethyl sulfoxide

Звездина

Мамардашвили

2012

Russ J Coord Chem

View full text Add to dashboard Cite

The metal exchange reactions of cadmium 5 monoaza 2, 3,7,8,12,13,17,18 octamethylporphyri nate with CuCl 2 and ZnCl 2 in dimethyl sulfoxide (DMSO) were studied by spectrophotometry. The kinetic and energy parameters of the metal exchange reaction were determined. The possible stoichiometric mech anism of the metal exchange reaction was proposed. A comparative analysis of the reaction rate constants obtained for the metal exchange and for the complex formation of 5 monoaza 2,3,7,8,12,13,17,18 octame thylporphyrin with the same salts in DMSO was performed.

show abstract

“…The spectral and kinetic studies were performed as described elsewhere [21,22]. Thermogravimetry tests were carried out using a NETZSCH TG 209 F1 instrument (specimen mass ≈5 mg, platinum crucible, heating rate 8.75 deg/min at 298-1223 K).…”

Section: Methodsmentioning

confidence: 99%

Synthesis and physico-chemical properties of 2,7,12,17-tetraphenylporphycene and its metal complexes

et al. 2015

Self Cite

View full text Add to dashboard Cite

Porphycene, β-phenyl-substituted analog of tetraphenylporphyrin, and its complexes with Cu(II) and Zn(II) have been prepared. Spectral parameters of the porphycene, its acid-base properties and thermal stability in the solid phase as well as its complexes stability towards dissociation in acidic medium have been studied by means of electronic absorption and NMR spectrometry, mass spectroscopy, thermogravimetry, and quantum chemistry simulation.Since the porphycenes are poorly available [3,8], their physico-chemical properties have been scarcely studied so far [3,9]. In this work, starting from the dipyrrole precursor I to prepare 2,7,12,17-tetraphenylporphycene [H 2 (β-Ph) 4 Por, II] [Eq. (1)] and its complexes with Cu(II) (III) and Zn(II) (IV) and studied spectral properties of the porphyrinoids, features of protonation and deprotonation of ligand II [Eq. (2)], its thermal stability in the solid phase, and stability of complexes III and IV against dissociation in acidic medium [Eq. (3)]. The obtained data allowed analysis of the reasons for similarity and difference of the properties of the porphyrin [meso-tetraphenylporphyrin

show abstract

Kinetic stability of corrole complexes with manganese, copper, and zinc in environments based on acetic and sulfuric acids

Cited by 9 publications

References 12 publications

Control of Molecular Catalysts for Oxygen Reduction by Variation of pH and Functional Groups

Control of Molecular Catalysts for Oxygen Reduction by Variation of pH and Functional Groups

Metal exchange reaction of cadmium 5-monoaza-2,3,7,8,12,13,17,18-octamethylporphyrinate with zinc(II) and copper(II) chlorides in dimethyl sulfoxide

Synthesis and physico-chemical properties of 2,7,12,17-tetraphenylporphycene and its metal complexes

Contact Info

Product

Resources

About