Association of radical anions alkali metal cations. III. Experimental and theoretical study of the associates of nitrobenzene radical anions with Li+, Na+, K+, Cs+ and (n-C4H9)4N+ cations

The nitrobenzene radical anion prepared by electrolysis was studied by UV spectroscopy. Formation of associates with Li+, Na+, K+, Cs+ and n(C4H9)4N+ cations was examined. It has been found that associates are also formed in a polar medium such as dimethylformamide. The enthalpy of the associated-free ion equilibrium was estimated as being equal to 6+4 kJ/mol-1. The quantum-chemical LHP method (in the π-approximation) was employed to study a simple ion pair model used for calculation of the most stable geometrical structure.

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Association of radical anions with alkali metal cations; II. Quantum-chemical study of the associates of glyoxal, nitrobenzene and fluorenone with lithium

Collection of Czechoslovak Chemical Communications ◽

10.1135/cccc19800351 ◽

1980 ◽

Vol 45 (2) ◽

pp. 351-359 ◽

Cited By ~ 4

Author(s):

Stanislav Miertuš ◽

Ondrej Kyseľ ◽

Pavol Mach

Keyword(s):

Experimental Data ◽

Quantum Chemical ◽

Hyperfine Splitting ◽

Ion Pairs ◽

Quantum Chemical Study ◽

Chemical Study ◽

Radical Anions ◽

Alkali Metal Cations ◽

Conjugated Molecules ◽

Energy Ratios

Some radical anions (glyoxal, fluorenone and nitrobenzene) were investigated by the modified LHP method. The calculated effects of cations (in ion pairs) and the effect of the polarity of the medium on energy ratios, conformation, hyperfine splitting constants and electronic spectra in the systems agree well with the available experimental data. It seems that the proposed modified LHP method can be useful in the study of ion-radical systems derived from larger conjugated molecules.

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Quantum-chemical approach to the ion pair formation (IPF) equilibrium constants of nitrobenzene radical anions with univalent cations and water molecul

Journal of Molecular Structure ◽

10.1016/0022-2860(75)80052-4 ◽

1975 ◽

Vol 28 (1) ◽

pp. 163-169

Author(s):

Tadeusz M. Krygowski ◽

Marek Lipsztajn ◽

Paweł Radzikowski

Keyword(s):

Quantum Chemical ◽

Equilibrium Constants ◽

Ion Pair ◽

Pair Formation ◽

Radical Anions ◽

Univalent Cations ◽

Ion Pair Formation ◽

Chemical Approach ◽

Quantum Chemical Approach

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Prebiotic Route to Thymine from Formamide—A Combined Experimental–Theoretical Study

Molecules ◽

10.3390/molecules26082248 ◽

2021 ◽

Vol 26 (8) ◽

pp. 2248

Author(s):

Lukáš Petera ◽

Klaudia Mrazikova ◽

Lukas Nejdl ◽

Kristyna Zemankova ◽

Marketa Vaculovicova ◽

...

Keyword(s):

Formic Acid ◽

Quantum Chemical ◽

Prebiotic Chemistry ◽

Theoretical Study ◽

Reaction Pathway ◽

Hydrolysis Product ◽

Current Paper ◽

Reaction Conditions ◽

Chemical Modeling ◽

Chemistry Research

Synthesis of RNA nucleobases from formamide is one of the recurring topics of prebiotic chemistry research. Earlier reports suggest that thymine, the substitute for uracil in DNA, may also be synthesized from formamide in the presence of catalysts enabling conversion of formamide to formaldehyde. In the current paper, we show that to a lesser extent conversion of uracil to thymine may occur even in the absence of catalysts. This is enabled by the presence of formic acid in the reaction mixture that forms as the hydrolysis product of formamide. Under the reaction conditions of our study, the disproportionation of formic acid may produce formaldehyde that hydroxymethylates uracil in the first step of the conversion process. The experiments are supplemented by quantum chemical modeling of the reaction pathway, supporting the plausibility of the mechanism suggested by Saladino and coworkers.

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