noun
definition
Any of a class of aromatic compounds having two carbonyl functional groups in the same six-membered ring.
Examples of quinone in a Sentence
A deep red solution was obtained, but the free quinone was not isolated since the solution on standing deposits nearly black crystals of dihydroxyphenylhydroxybenzoquinone (HO)2C6H3 C6H202.OH.
For naphthalene quinones see Naphthalene; for anthracene quinone see Anthraquinone; and for phenanthrene quinone see Phena Nt H Rene.
Hantzsch (Ber., 18 99, 3 2, pp. 59 o, 3089) considers that the oxyazo compounds are to be classed as pseudoacids, possessing in the free condition the configuration of quinone hydrazones, their salts, however, being of the normal phenolic type.
The so-called chrysophanic acid found in Xanthoria (Physcia) parietina is not an acid but a quinone and is better termed physcion.
On oxidation .ith chromic acid it forms a quinone, C 15 H 8 0 2, and an a-diphenylene keto carboxylic acid C E I-4 3.
Quinone, which is light yellow in colour, is the simplest coloured substance on this theory.
He suggests that the term " quinone " theory be abandoned, and replaced by the Umlagerungs theory, since this term implies some intermolecular rearrangement, and does not connote simply benzenoid compounds as does " quinonoid."
Manganese dioxide and dilute sulphuric acid oxidize it to quinone.
Chromic acid oxidizes it to retene quinone, phthalic acid and acetic acid.
It behaves more as a ketone than as a quinone, since with hydroxylamine it yields an oxime, and on reduction with zinc dust and caustic soda it yields a secondary alcohol, whilst it cannot be reduced by means of sulphurous acid.
Benzoquinone (para) or ordinary quinone, C 6 H 4 0 2, is formed by the oxidation of aniline with sodium bichromate and sulphuric acid.
Fittig (Ann., 1876, 180, p. 23) readily explains the formation of the monoand di-oximes of quinone and also that it readily combines with bromine.
Quinhydrone, C 6 H40 2 -C 6 H 4 (OH) 2, is formed by the direct union of quinone and hydroquinone or by careful oxidation of hydroquinone with ferric chloride solution.
On boiling with water it decomposes into quinone and hydroquinone.
It has the character of a quinone.
Chromic acid converts it into quinone, while chlorates, in the presence of certain metallic salts (especially of vanadium), give aniline black.
Two of the compounds also led to a fourfold boost in production of a detoxifying enzyme called quinone reductase in mouse liver cells.
In order to synthesize alizarin, they converted anthracene into anthraquinone and then brominated the quinone.