Electroreduction of aromatic oximes: Diprotonation, adsorption, imine formation, and substituent effects

Result code in IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F61388955%3A_____%2F06%3A00085407" target="_blank" >RIV/61388955:_____/06:00085407 - isvavai.cz</a>

Result on the web

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DOI - Digital Object Identifier

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Result language

angličtina

Original language name

Electroreduction of aromatic oximes: Diprotonation, adsorption, imine formation, and substituent effects

Original language description

Aromatic oximes are reduced in aqueous solution in a four-electron process. The reducible species in the pH range 5-8 is a diprotonated form of the oxime. This species is generated in the course of electrolysis in the vicinity of the electrode surface from the adsorbed neutral form of the oxime. The reduction is initiated by a cleavage of the N-O bond. The diprotonation facilitates the reduction process by the preformation of OH2+ as a good leaving group and by a positive charge on the azomethine nitrogen. Diprotonation has been proven based on shapes of i = f(pH) plots, by observed shifts of half-wave potentials with pH and by comparison with the reduction of nitrones. Some observed deviations from theoretical i =f(pH) plots were attributed to the role of adsorption on the rate of protonation. Adsorption is also responsible for dips on some of the i-E curves. Adsorption plays a role at concentrations as low as 1 x 10(-5) M, when the electrode surface is still not fully covered.

Czech name

Elektroredukce aromatických oximů: Diproporcionace, adsorpce, tvorba iminů a vlivy substituentů

Czech description

Při pH 5-8 se aromatické oximy redukují v diprotonovaném stavu, který je stabilizován adsorpcí na elektrodě. Celková redukce probíhá čtyřmi elektrony: první se rozštěpí vazba N-O za vzniku iminu jakožto meziproduktu, který se dále redukuje a paralelně hydrolyzuje. Je diskutován vliv pKa protonovaných forem iminů i oximů na tvar redukční křivky a vliv substituentů v p-poloze na potenciál redukce.

Type

J_x - Unclassified - Peer-reviewed scientific article (Jimp, Jsc and Jost)

CEP classification

CG - Electrochemistry

OECD FORD branch

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Project

Result was created during the realization of more than one project. More information in the Projects tab.

Continuities

P - Projekt vyzkumu a vyvoje financovany z verejnych zdroju (s odkazem do CEP)<br>Z - Vyzkumny zamer (s odkazem do CEZ)

Publication year

2006

Confidentiality

S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů

Name of the periodical

Journal of Physical Chemistry B

ISSN

1520-6106

e-ISSN

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Volume of the periodical

110

Issue of the periodical within the volume

13

Country of publishing house

US - UNITED STATES

Number of pages

12

Pages from-to

6785-6796

UT code for WoS article

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EID of the result in the Scopus database

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