The electrochemical oxidation of iodide ion in the presence of 4-hydroxycoumarin (1) was studied using cyclic voltammetry and controlled-potential coulometry. The result indicates that the resulting iodine takes part in a halogenation reaction and reacts with 4-hydroxycoumarin (1). According to the obtained results, a new and simple coulometric titration method with potentiometric end-point det...

Electrochemical oxidation of the catechols 1a and 1b is studied in the presence of 6-methyl-2-thouracil (3b) and 6-propyl-2-thiouracil (3a) as nucleophiles in a phosphate buffer (0.15 mol L−1, pH = 6.8)/DMF (95:5) solution using cyclic voltammetry and controlled-potential coulometry. The results obtained indicate that the quinones derived from the catechols participate in 1,4-Michael-addition r...

Z. Naturforsch. 43b, 475-482 (1988); received February 13/October 22, 1987 Electron Transfer Relays, Viologen Derivatives, Bipyridinium Compounds, Stable Cation Radicals, Photoinduced Water Splitting The synthesis of some new bipyridinium salts is described. Their behavior upon reduction is studied by cyclovoltammetry, coulometry and spectroscopically. Halfwave potentials range from —0.28 V to ...

An overview of our recent studies dealing with infrared-induced conformational interconversion of carboxylic acids isolated in rare-gas matrices is presented. Extensive rotational photoisomerization studies have been performed on formic acid, which is the simplest organic acid enabling this kind of processes. Formic acid has two conformers and interconversion between them can be induced by vibr...

The precipitation titration of sodium chloride with electrogenerated silver ion was studied. The production of a precipitate of silver chloride had a significant effect on the titration results because the precipitate involved unreacted chloride or unreacted silver ion. The accuracy of the method was investigated by changing the introduction time of a sodium chloride solution to the coulometric...

The mechanism of the electrochemical oxidation of 2,5-dihydroxybenzoic acid and 3,4-dihydroxybenzaldehyde in the presence of 3-hydroxy-1H-phenalene-1-one as a nucleophile has been studied in water/acetonitrile (80/20 v/v) solution using cyclic voltammetry and controlled-potential coulometry methods. The results indicate that the quinones derived from oxidation of 2,5-dihydroxybenzoic acid and 3...

The electroreduction of bovine serum albumin (BSA) in pH 7.4 solution was studied at the hanging mercury drop electrode by double potential step chronocoulometry and cyclic voltammetry. and at a mercury pool electrode by controlled potential coulometry. The proposed mechanism involves reduction of an adsorbed monolayer of BSA (maximum coverage 3.3 1lC-2); at short times 3 or 4 disulfide bonds a...