A Fluorine 1,2-Migration via Aryl Cation/Radical/Radical Anion/Radical Sequence

2013 ◽  
Vol 15 (15) ◽  
pp. 3926-3929 ◽  
Author(s):  
Luca Pretali ◽  
Daniele Dondi ◽  
Mila D’Angelantonio ◽  
Ilse Manet ◽  
Elisa Fasani ◽  
...  
Keyword(s):  
Radical Anion ◽  
Anion Radical ◽  
Cation Radical

ChemInform Abstract: Electron Transfer Photochemistry of Aromatic Imides and Phenylcyclopropane. Radical Anion-Radical Cation Cycloaddition.

ChemInform ◽  
1987 ◽  
Vol 18 (11) ◽  
Author(s):  
P. H. MAZZOCCHI ◽  
C. SOMICH ◽  
M. EDWARDS ◽  
T. MORGAN ◽  
H. L. AMMON
Keyword(s):  
Electron Transfer ◽  
Radical Cation ◽  
Radical Anion ◽  
Anion Radical

Spectroelectrochemical characterization of meso triaryl-substituted Mn(IV), Mn(III) and Mn(II) corroles. Effect of solvent and oxidation state on UV-visible spectra and redox potentials in nonaqueous media

2014 ◽  
Vol 18 (12) ◽  
pp. 1131-1144 ◽  
Author(s):  
Bingbing Gao ◽  
Zhongping Ou ◽  
Xueyan Chen ◽  
Shi Huang ◽  
Bihong Li ◽  
...  
Keyword(s):  
Anion Radical ◽  
Cation Radical ◽  
Oxidation Mechanism ◽  
Central Metal ◽  
Redox Potentials ◽  
Nonaqueous Media ◽  
Visible Spectra ◽  
Phenyl Rings ◽  
Uv Visible

Two series of substituted manganese triarylcorroles were synthesized and characterized as to their electrochemical and spectroelectrochemical properties in CH 2 Cl 2, CH 3 CN and pyridine. The investigated compounds are represented as ( YPh )3 CorMn III and ( YPh )3 CorMn IV Cl , where Cor is a trianion of the corrole and Y is a Cl , F , H or CH 3 para-substituent on the three phenyl rings of the macrocycle. Each neutral Mn(III) corrole exists as a four-coordinate complex in CH 2 Cl 2 and CH 3 CN and as a five-coordinate species in pyridine. ( YPh )3 CorMn III undergoes two oxidations to stepwise generate a Mn(IV) corrole and a Mn(IV) π-cation radical. It also undergoes one reduction to generate a Mn(II) corrole in CH 2 Cl 2 or CH 3 CN . In contrast, the reduction of ( YPh )3 CorMn III leads to a Mn(III) corrole π-anion radical in pyridine. One oxidation is observed for ( YPh )3 CorMn IV Cl in CH 2 Cl 2 and CH 3 CN to generate a Mn(IV) corrole π-cation radical while Mn(III) and Mn(II) corroles are stepwise formed after reduction of the same compound. The second reduction of ( YPh )3 CorMn IV Cl in pyridine gives a Mn(III) π-anion radical as opposed to a Mn(II) corrole with an unreduced π-ring system. The neutral, reduced and oxidized forms of each corrole were characterized by electrochemistry and UV-visible spectroelectrochemistry and comparisons are made between the UV-visible spectra and redox potentials of the compounds in different central metal oxidation states. An overall reduction/oxidation mechanism in the three solvents is proposed.

Chemical repair mechanisms of damaged tyrosyl and tryptophanyl residues in proteins by the superoxide radical anion

2020 ◽  
Vol 44 (6) ◽  
pp. 2505-2513
Author(s):  
Leonardo Muñoz-Rugeles ◽  
Annia Galano ◽  
Juan Raúl Alvarez-Idaboy
Keyword(s):  
Superoxide Anion ◽  
Radical Anion ◽  
Anion Radical ◽  
Superoxide Radical ◽  
Superoxide Anion Radical ◽  
Superoxide Radical Anion ◽  
Diffusion Controlled ◽  
Repair Mechanisms

Even though reaction of the superoxide anion radical/hydroperoxide radical could lead to oxidation of biomolecules, it can repair oxidized tyrosyl and tryptophanyl residues in proteins at diffusion-controlled rates.

Radical reactions of p-Nitrobenzylidene dichloride with lithium 2-nitropropan-2-ide. Consecutive SRN1 and ERC1 reactions

1976 ◽  
Vol 29 (12) ◽  
pp. 2631 ◽  
Author(s):  
DJ Freeman ◽  
RK Norris
Keyword(s):  
Radical Anion ◽  
Anion Radical ◽  
Lithium Salt ◽  
Substituent Effects ◽  
Radical Reactions ◽  
Elimination Reaction ◽  
Radical Chain ◽  
Radical Processes

The reaction of p-nitrobenzylidene dichloride with the lithium salt of 2-nitropropane gives initially the monosubstituted compound, p- NO2C6H4CH(Cl)CMe2NO2, by a radical-anion radical chain, SRN1 process. This compound then undergoes a radical-anion radical chain elimination reaction giving the styrene, p-NO2C6H4CH=CMe2, and the dimer of 2- nitropropane, Me2C(NO2)CMe2NO2. This latter reaction, which is designated ?ERC1?, also occurs in competition with an E2 reaction in the reaction of the methanesulphonate, p-NO2C6H4CH(OMs)CMe2NO2, with the 2- nitropropan-2-ide ion giving the above styrene and the enol methanesulphonate, p-NO2C6H4C(OMs)=CMe2, respectively. Catalytic, inhibition, and substituent effects are used to confirm the operation of these radical processes.

Nucleophilic substitution reactions in m-nitrobenzylic substrates

1983 ◽  
Vol 36 (1) ◽  
pp. 81 ◽  
Author(s):  
SD Barker ◽  
RK Norris
Keyword(s):  
Nucleophilic Substitution ◽  
Radical Anion ◽  
Anion Radical ◽  
The Other ◽  
Radical Anions ◽  
Malonic Ester ◽  
Mechanism Of Formation ◽  
Substitution Reactions ◽  
Radical Process ◽  
Rule Out

The reaction of m-nitrobenzyl 2,4,6-trimethylbenzoate (11) with the salt (2) of 2-nitropropane, or the thiolate (16), gives moderate yields of substitution products [e.g.(3) or (17)]. However, the mechanism of formation of these products could not be definitively assigned. The m-nitrobenzyl chloride (12), on the other hand, was clearly demonstrated to undergo SRN1 substitution reactions with a variety of anions including the anion from the salt (2), thiolate ion from (16), azide from (22), the malononitrile anion from (20), and the malonic ester anion from (21). Inhibition and entrainment effects clearly rule out an alternative radical anion-radical process involving cage collapse. The occurrence of SRNl reactions in m-nitrobenzylic substrates adds support to a mechanism involving association of radicals with anions, and for dissociation of radical anions, which involves σ* and π* radical anions.

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