Reactions of the iron(III) tetraphenylporphyrin .pi. cation radical with triphenylphosphine and the nitrite anion. Formation of .beta.-substituted iron(III) porphyrins

Malek, Andrzej; Latos‐Grażyński, Lechosław; Bartczak, Tadeusz J.; Żądło, Andrzej

doi:10.1021/ic00016a021

Cited by 44 publications

(29 citation statements)

References 4 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…72,73 Similar β-substitutions were also observed by other groups. [74][75][76] Moreover, as previously found for porphyrins in the OEP series, in the case of methanol, the reaction stopped at the formation of isoporphyrin. 62,73,77 A same feature was observed in the case of the use of hydroperoxide.…”

Section: B Nucleophilic Substitutions Onto Porphyrins By a Chemical supporting

confidence: 73%

Electrosynthesis Processes Based on Oxidative Couplings of Porphyrins for the Formation of Supramolecular Assemblies

Schaming¹

2014

Handbook of Porphyrin Science (Volume 32)

View full text Add to dashboard Cite

Section: B Nucleophilic Substitutions Onto Porphyrins By a Chemical supporting

confidence: 73%

Electrosynthesis Processes Based on Oxidative Couplings of Porphyrins for the Formation of Supramolecular Assemblies

Schaming¹

2014

Handbook of Porphyrin Science (Volume 32)

View full text Add to dashboard Cite

“…The addition of another molecule of NO 2 to a cation radical thus formed, results in the formation of an arenium cation. The formation of arenium cation intermediates via the radical pathway has been proposed to occur in the nitration reactions of metallocorroles and metalloporphyrins, though the involvement of the added co‐oxidant to the reaction along with the nitration agent was ambiguous in certain cases …”

Section: Resultsmentioning

confidence: 99%

Nitration of Norcorrolatonickel(II): First Observation of a Diatropic Current in a System Comprising a Norcorrole Ring

Deng

Stępień

et al. 2016

Chemistry A European J

View full text Add to dashboard Cite

A one-pot reaction of 5,14-bis(mesityl)-norcorrolatonickel(II) with isoamyl nitrite under mild reaction conditions resulted in the consecutive formation of 3-nitro-, 3,12-dinitro- and 3,16-dinitro-, 3,7,12-trinitro-, and 3,7,12,16-tetranitro-norcorrolatonickel(II) in 50-80% yield. The substituted macrocycles retained their antiaromatic character. The observed regioselectivity of the substitution was analyzed by comparing the relative energies of the DFT energy-optimized models of the radical or arenium cationic intermediates that can be formed upon reaction with NO2. The nitrated systems were characterized by high-resolution mass spectrometry, NMR and UV/Vis spectroscopy, X-ray diffraction analysis, cyclic voltammetry, and DFT calculations. A significant and systematic cathodic shift of the redox couples was observed to correlate with an increasing number of the NO2 group. A decrease of the LUMO energies in the tri- and tetra-nitrated products stabilizes mono- and bis-reduced complexes of these ligands. The reduction takes place on the macrocycle rather than on the metal ion leading to the consecutive formation of stable paramagnetic monoanion radicals and water-soluble diamagnetic dianions with an aromatic character, which were revealed by ESR and (1)H NMR measurements, respectively. The electronic structures of the reduced forms were analyzed by extensive TD-DFT calculations.

show abstract

“…With few exceptions, the new arrays [6] or products of the oxidation reactions [22,23] have not been characterized crystallographically. This dearth of structural data becomes particularly important because multiple peripheral substitutions in porphyrins have been shown to induce significant conformational distortions of the porphyrin skeleton that minimize steric interactions between the substituents [24,25].…”

Section: Introductionmentioning

confidence: 99%

Electrosynthesis, electrochemistry, and crystal structure of the tetracationic Zn-meso-tetrapyridiniumyl-β-octaethylporphyrin

Giraudeau¹,

Lobstein²,

Ruhlmann

et al. 2001

J. Porphyrins Phthalocyanines

View full text Add to dashboard Cite

ABSTRACT:Exhaustive electro-oxidation of ZnOEP in the presence of pyridine and Et 4 NPF 6 affords in high yield the new tetracationic porphyrin in which the four meso protons of ZnOEP are replaced by four pyridinium groups linked via their nitrogens: 10,15,3,7,8,12,13,17, 4 PF À 6 4 , 1. The compound has been characterized by elemental analysis, 1 H NMR, and crystallography. The latter confirms the preparative electrosynthetic methodology and molecular structure of 1, and shows the porphyrin skeleton to adopt a severely nonplanar saddle conformation which minimizes steric crowding between the 12 peripheral substituents. As a consequence of the nonplanarity (and the high charge) of the complex, 1 exhibits significant redshifts of the visible and Soret bands as well as a considerable broadening and loss of intensity of the latter. 1 first undergoes four one-electron reduction steps at the four pyridinium sites before the normal one-electron reduction of the porphyrin p-system.

show abstract

Reactions of the iron(III) tetraphenylporphyrin .pi. cation radical with triphenylphosphine and the nitrite anion. Formation of .beta.-substituted iron(III) porphyrins

Cited by 44 publications

References 4 publications

Electrosynthesis Processes Based on Oxidative Couplings of Porphyrins for the Formation of Supramolecular Assemblies

Electrosynthesis Processes Based on Oxidative Couplings of Porphyrins for the Formation of Supramolecular Assemblies

Nitration of Norcorrolatonickel(II): First Observation of a Diatropic Current in a System Comprising a Norcorrole Ring

Electrosynthesis, electrochemistry, and crystal structure of the tetracationic Zn-meso-tetrapyridiniumyl-β-octaethylporphyrin

Contact Info

Product

Resources

About