ChemInform Abstract: CONTRIBUTIONS TO THE STUDY OF HETEROCYCLES PART 40, POLAROGRAPHIC REDUCTION OF SOME HETEROCYCLIC ALDEHYDES

A mechanism of the electrochemical reduction of β-(4-ethylbenzoyl)-α,β-dibromopropionic acid is suggested based on the results of classical polarography and polarography with Kalousek's switch and on the identification of the polarographically active intermediate products. The substance converts to β-4-ethylbenzoylacrylic acid on the electrochemical elimination of the bromine atoms, and the latter acid is reduced further to β-4-ethylbenzoylpropionic acid. The most negative polarographic wave corresponds to the reduction of the carbonyl group in the benzoyl part of the last acid.

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Polarography of N,N-dimethyl-4-amino-4'-hydroxyazobenzene in water-methanol mixtures

Collection of Czechoslovak Chemical Communications ◽

10.1135/cccc19850712 ◽

1985 ◽

Vol 50 (3) ◽

pp. 712-725 ◽

Cited By ~ 2

Author(s):

Jiří Barek ◽

Lubomír Kelnar

Keyword(s):

Differential Pulse ◽

Differential Pulse Polarography ◽

Polarographic Reduction ◽

Reduction Mechanism ◽

Pulse Polarography ◽

Methanol Medium

The polarographic reduction of N,N-dimethyl-4-amino-4'-hydroxyazobenzene in water-methanol medium was investigated. Evidence is presented for adsorption of the depolarizer on the electrode, and a reduction mechanism is proposed. Conditions are indicated for the determination of this compound in the concentration range 10-4-10-6 mol/l by d.c. polarography, 10-5 to 3 . 10-7 mol/l by Tast polarography, and 10-5-3 . 10-8 mol/l by differential pulse polarography.

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Polarographic reduction of 1-(p-substituted benzyl)-3-cyanopyridinium chlorides

Collection of Czechoslovak Chemical Communications ◽

10.1135/cccc19832273 ◽

1983 ◽

Vol 48 (8) ◽

pp. 2273-2283

Author(s):

Františka Pavlíková-Raclová ◽

Josef Kuthan

Keyword(s):

Substituent Effects ◽

Polarographic Reduction

Reduction of 3-cyanopyridinium salts has been studied on the mercury dropping electrode. Solvent and substituent effects and pH of the medium have been shown to modify in a certain extent differently the polarographic characteristics as compared with analogous 3-carbamoyl derivatives, which is due to higher electronegativity of the studied cations.

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The polarographic and voltammetric determination of 2,6-dicyano-4-nitro-2'-acetylamino-4'-diethylaminoazobenzene

Collection of Czechoslovak Chemical Communications ◽

10.1135/cccc19901508 ◽

1990 ◽

Vol 55 (6) ◽

pp. 1508-1517 ◽

Cited By ~ 1

Author(s):

Jiří Barek ◽

Dagmar Civišová ◽

Ashutosh Ghosh ◽

Jiří Zima

Keyword(s):

Azo Dye ◽

Differential Pulse ◽

Differential Pulse Polarography ◽

Determination Limit ◽

Polarographic Reduction ◽

Hanging Mercury Drop Electrode ◽

Optimal Conditions ◽

Pulse Polarography ◽

Pulse Voltammetry

The polarographic reduction of the title azo dye was studied and optimal conditions were found for its analytical utilization in the concentration range 1 . 10-6 - 1 . 10-7 mol l-1 using differential pulse polarography and 1 . 10-6 - 1 . 10-8 mol l-1 using fast scan differential pulse voltammetry or linear scan voltammetry at a hanging mercury drop electrode. When the latter technique is combined with adsorptive accumulation of the studied substance on the surface of the hanging mercury drop, the determination limit can be further decreased to 3 . 10-9 mol l-1.

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