Studies on Humic Acids. V. The Reaction of p-Benzoquinone with Alkali.

Erdtman, H.; Granath, Märta; Linholt, S. C.; Sørensen, Nils Andreas

doi:10.3891/acta.chem.scand.08-0811

Cited by 19 publications

(8 citation statements)

References 0 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Pt/Pt-oxide, IrO 2 and Sn(Sb-doped) oxide) does not depend strongly on current density and, hence, on potential for the experimental conditions used here. However, it is also known that p-benzoquinone undergoes condensation/polymerization reactions in acidic and alkaline solutions [12,13]. This results in a variety of products, their nature being also influenced by the presence of O 2 [12].…”

Section: The Influence Of J On W Oxorg and I Effmentioning

confidence: 99%

“…However, it is also known that p-benzoquinone undergoes condensation/polymerization reactions in acidic and alkaline solutions [12,13]. This results in a variety of products, their nature being also influenced by the presence of O 2 [12]. An increase in j results in pH changes near the electrode surfaces as well as in an increase production of O 2 (see reaction 1 (1.1, 1.2, 1.3)).…”

Section: The Influence Of J On W Oxorg and I Effmentioning

confidence: 99%

“…0 -12). This decrease is likely to be related to condensation/polymerization reactions of p-benzoquinone known to occur in acidic and alkaline solutions [12,13]. For the anodic oxidation, a geometrical anode area of 1.7 cm 2 (1.4 ×1.2 cm) was exposed to the electrolysis solution.…”

Section: Oxidation Of P-benzoquinonementioning

confidence: 99%

See 2 more Smart Citations

The influence of metal oxide properties on the oxidation of organics

Bock

MacDougall

2000

Journal of Electroanalytical Chemistry

View full text Add to dashboard Cite

The 'anodic oxidation' of p-benzoquinone has been studied using a range of anode materials. The influence of the applied current density on the removal rate of p-benzoquinone has also been studied. An increase in the applied current density was found to increase the removal rate of p-benzoquinone only slightly, thus resulting in an actual decrease of the current efficiency of this process. The removal rate for p-benzoquinone was found to be influenced by several properties of the anode material. In fact, a relationship between properties of the anode such as its electroactive surface area and the removal rate of organics appears to exist. Crown

show abstract

Section: The Influence Of J On W Oxorg and I Effmentioning

confidence: 99%

Section: The Influence Of J On W Oxorg and I Effmentioning

confidence: 99%

See 1 more Smart Citation

The influence of metal oxide properties on the oxidation of organics

Bock

MacDougall

2000

Journal of Electroanalytical Chemistry

View full text Add to dashboard Cite

show abstract

“…Decomposition of quinones at alkaline pH is caused by the addition of OH-ions at the quinone moiety and leads to the formation of, among other products, the corresponding hydroquinone [29,30]. Indeed, an oxidation wave of the hydroquinone was frequently observed in the polarograms at alkaline pH.…”

Section: Electrochemrcal Properties Of Unsubstrtuted Qulnonesmentioning

confidence: 99%

Electrochemistry of potentially bioreductive alkylating quinones

Driebergen

Hartigh

Holthuis

et al. 1990

Analytica Chimica Acta

View full text Add to dashboard Cite

The mfluence of methyl-, hydroxy and ammo substituents on the electrochen-ucal behavlour of simple l,Cnaphthoand l,Cbenzoqumones, model compounds of many qumoid antitumour agents, m aqueous media was studied Sigmficant changes m electrochenncal behaviour were observed, potentially the result of a change m the electron density of the qumone moiety, pre-or post-protonation of substituents, hydrogen bond formation, tautomenzation reactions and stenc mteractions between the qumone moiety and substituents. The mformation obtained was of benefit m the elucidation of the reduction mechanisms of qumoid antitumour agents such as avndmylqumones and mitomycins Many well-known anticancer agents, such as the anthracyclines (doxorubicin), the rmtomycins (mitomycm C) and the aziridmylqumones (carboquone and trenimon), have a quinone function, whereas mitoxantrone, AZQ and BZQ are more recently developed quinoid agents, currently m phase I and II clinical trials (Fig. 1).

show abstract

“…The necessity for dehydrogenation of reductones to a-dicarbonyl compounds and of polyphenols to o-quinones before typical browning can occur (in aqueous systems) was emphasized by Hodge in 1953 (8). Further evidence has been provided in support of that contention (2,3,4,6,10). The present work indicates that the dehydrogenation hypothesis should be extended to include browning in oils and in fatty systems.…”

Section: Discussionmentioning

confidence: 99%

Development of color in fats stabilized with amino‐hexose‐reductones

Cooney

Hodge

Evans

1958

J Americ Oil Chem Soc

View full text Add to dashboard Cite

o NE REQUIREMENT for an acceptable antioxidantis the absence of color development in the fatty substrate. It was known at the time this investigation was undertaken that reduetones would impart some added browning to stabilized fats. However, because amino reductones are among the most potent substances to prevent oxidation of fats and are among the very few substances that show an appreciable antioxidant activity in soybean oil (5), this investigation on color development in reductonetreated oils was undertaken. Hodge (7,8,9) has discussed the browning reactions of amino and nonamino reductones in nonfat systems. The development of color by nonamino reductones (aseorbic acid and its esters, catechol, and hydroquinone) when used as antioxidants in fats has apparently not been a problem. These reductones however are well known for their browning reactions in foods and aqueous systems. Regier and Tappel (12) report that 1% concentrations of ascorbic acid, morpholino-, piperidino-, and dimethylamino-hexose-reduetones induced rapid visual browning in freeze-dried beef.Aqueous solutions of amino-hexose-reductones darken upon standing in air. The dehydro form of reductone further oxidizes and polymerizes, changing from yellow (in dilute solutions) or reddish (in concentrated solutions) to dark brown melanoid-like substances (3). ExperimentalVarious reductones in antioxidant concentration ranges of 0.005 to 0.02% ~ere evaluated for color development in soybean oil, cottonseed oil, lard, and shortening. The reduetones were added as a 1% solution in 90% ethyl alcohol to fats on the cooling side of deodorization. With this technique, peroxide-free systems were attained; also a minimum of air was introduced into the sample. All samples of fats and oils were of commercial origin and, as judged by physical constants and stability tests, were typical and representative materials.Color was measured by the A.O.C.S. tentative speetrophotometrie method (11), and a few investigations were made in the visible and ultraviolet spectra with a Beckman Model DU speetrophotometer. Color development was measured on fats stored in loosely stoppered bottles held at 60~ (Schaal oven conditions) for periods up to three months and on samples stored at 100~Tests for shorter periods of time were conducted on fat samples under A.O.lVL oxidizing conditions. Deep-fat frying tests were conducted at 196~ to determine the browning developed under these conditions (1). For uniformity the samples for evaluation were removed periodically from a single, larze lot of material that was undergoing test.The lack of a good method for determining low concentrations of peroxides and reductones in the presence of each other, and the fact that previous tests had shown that oils stored under Sehaal oven

show abstract

Studies on Humic Acids. V. The Reaction of p-Benzoquinone with Alkali.

Cited by 19 publications

References 0 publications

The influence of metal oxide properties on the oxidation of organics

The influence of metal oxide properties on the oxidation of organics

Electrochemistry of potentially bioreductive alkylating quinones

Development of color in fats stabilized with amino‐hexose‐reductones

Contact Info

Product

Resources

About