2.5- Dihydroxy-p-benzoquinone

Anhydro-(6-nitro-2,5-dihydroxy-p-benzoquinone-3-diazohydroxide) [called Anhydro-[6-nitro-2.5-di oxy-p-chinon-diazohy droxy d-( 3)] Anhydro-[6-nitro-4.5-dioxy-o-chinon-diazo-hydroxyd-(3)] or 3-Diazid des 6-Nitro-cyclohexanpentons-(1.2.3-4.5) in Gerj ... 

Anhydro-(6-nitro-2,5-dihydroxy-p-benzoquinone-3-diazohydroxide) 5 D1290... 

GC-MS and HPLC analyses of electrolyzed solutions allowed the detection of aromatic intermediates such as p-benzoquinone and nitrobenzene for aniline, 4-chlorocatechol for 4-chlorophenol, 4-chlorophenol, 4-chlorocatechol, hydroquinone, and p-benzoquinone for 4-CPA, 4-chloro-o-cresol, mehylhy-droquinone, and methyl-p-benzoquinone for MCPA, 2,4-dichlorophenol, 4,6-dichlororesorcinol, chlorohydroquinone, and chloro-p-benzoquinone for 2,4-D, and 2,4,5-trichloro-phenol, 2,5-dichlorohydroquinone, 4,6-dichlororesorcinol, and 2,5-dihydroxy-p-benzoquinone for 2,4,5-T. In general, these by-products persisted in solution while the initial pollutant was degraded. 

THERMAL AND SPECTRAL STUDY OF SOME DIVALENT METAL CHELATES OF 2,5-DIHYDROXY-P-BENZOQUINONE. 

Rigid rod-shaped materials were synthesized fi om one-to-one complexes of 2,5-dihydroxy-p-benzoquinone with Cu(II), Ni(II), and Cd(II) (11). ° Rods 1000-2000 A long were claimed. 

The commercially available 2,5-dihydroxy-p-benzoquinone 194 reacted with 1.1 equivalents of various substituted 1,2-DABs 155 to afford high yields of substituted 2,3-dihydroxyphenazines 195 (Yosioka andOtomasu 1954 Romeretal. 1979 Pozzo et al. 1998 Seillan et al. 2008). These could be reacted further over 24 h with an excess of substituted 1,2-DABs 155a, b, k, 1 (10 equivalents) in the presence of glacial AcOH yielding pentacyclic derivatives 196 (Scheme 2.10) (Seillan et al. 2008). 

BON 13] Bonnard G., Barr6s A.-L., Mentr O., et al., The low/room-temperature forms of the lithiated salt of 3,6-dihydroxy-2,5-dimethoxy-p-benzoquinone a combined... 

A. Mercury(II) chloranilate method Discussion. The mercury(II) salt of chloranilic acid (2,5-dichloro-3,6-dihydroxy-p-benzoquinone) may be used for the determination of small amounts of chloride ion. The reaction is ... 

Substituted benzylideneanilines form molecular complexes187 with 106 and with 2,5-dichloro-3,6-dihydroxy-p-benzoquinone (110) (chloranilic acid). These complexes were investigated by IR and 111 NMR. The complexes between benzylideneanilines and 106 are CT complexes (111), while complexes with 110 are formed through electron and proton transfer187, as illustrated in 112. In 111, a refers lo n -> jr interaction and b is a jr -> jr interaction, sp2 N-atoms of some heterocyclic imines (such as 2,2 -bipyridyl, 1,10-phenantroline) are also n-donors towards acceptors (tetracyanoethylene, p-benzoquinone, chloranil)188. 

If nitrogen and/or sulphur is present, acidify 3-4 ml of the fusion solution with dilute nitric acid and evaporate to half the original volume in order to expel any HCN and/or H2S which may be present. If nitrogen and sulphur are absent, proceed directly with 2 ml of the sodium fusion filtrate. Render the solution just neutral to litmus by the addition of dilute (5 m) aqueous ammonia solution, then add 5 drops of 5 m acetic acid and 20 mg of lanthanum chloranilate (2,5-dichloro-3,6-dihydroxy-p-benzoquinone, lanthanum salt) and shake intermittently for 10-15 minutes. Filter. A pink-violet coloration of the filtrate is a positive test for fluorine. 

The compounds studied were 2-methoxyhydroquinone A, 4-methylcatechol B, 2-hydroxy-2,3,3,-trimethoxy-5,5 -di-n-propylbiphenyl C, methoxy-p-benzoquinone D, 4,4 -dimethoxybiphenyl-2,5,2,5,-bisquinone E, 8-hydroxy-3,7-dimethoxydi-benzofuran-l,4-quinone F, 2,5-dihydroxy-2, 3,3 -trimethoxy-5 -hydroxymethyl-biphenyl G, and the related p-quinone H (scheme 1). Compounds A, D, E, and F were synthesized according to ref. [9], and compound Q, was prepared from 2-hydroxy-2,3,3,-trimethoxy-5-formyl-5,-hydroxymethyldiphenyl by Dakin reaction using the same procedure as for compound A. Compound G was isolated in presence of the corresponding p-quinone H. Titration of H was performed by... 

SYNS 2,5-DICHLORO-3,6-DIHYDROXY-p-BENZOQUINONE, MERCURY SALT (2,5-DICHLORO-3,6-DIHYDROXY-p-BENZOQUINONE), MERCURY SALT... 

Beaumont, P.C., and R.L. Edwards Constituents of the Higher Fungi IX. Bovin-one, 2,5-Dihydroxy-3-geranylgeranyl-l,4-benzoquinone from Boletus Suillus) bovin-us (Linn, ex Fr.) Kuntze. J. Chem. Soc. (London) C 1969, 2398. 

An aq. suspension of p-benzoquinone added slowly at room temp, to an aq. suspension of p-( -bromoethyl)benzenesulfinic acid 2,5-dihydroxy-4 -(/ -bromoethyl)diphenyl sulfone. Y 81%. I. H. Spinner, J. Yannopoulos, and W. Metanomski, Gan. J. Ghem. 39, 2529 (1961). 

CsH O, 2,5-Dihydroxy-1,4-benzoquinone, 43B, 153 CsH5N02r Quinone-4-oxime, 40B, 121 C6H6Cl20e, Chloranilic acid dihydrate, 32B, 106 C6H8N808r Ammonium nitranilate, 29, 648 32B, 47 CsH808f Tetrahydroxy-p-benzoquinone, 30B, 77... 

Aryl isocyanates react at elevated temperatures with benzoquinone to give p-quinone-bis-imides with elimination of carbon dioxide. When the reaction of 2,5-dihydroxy-1,4-benzoquinone with aryl isocyanates is conducted in DMSO, in the presence of triethylamine, addition across the C=C bond occurs with formation of the rearrangement products, 2,5-dihydroxy-3,6-bis(anilinocarbonyl)-l,4-benzoquinones in 19-68 % yields ". ... 

The reaction mixture from acidified dihydroxyacetone also included a series of seven di- and tri-hydroxybenzenes (see Scheme 4), namely, 2,3-dihydroxytoluene (16), pyrocatechol (17), 3,4-dihydroxy toluene (19), 3,5-dimethyl-l,2-benzenediol (20), 1,2,3-trihydroxybenzene (pyrogallol) (21), 1,2,4-trihydroxy benzene (22), 3,4,5,6-tetrahydroxy-2-methy 1-acetophe-none, and 2,3-dihydroxy-5,6-dimethyl-p-benzoquinone. Many of these same phenolic compounds are present after hexoses are similarly treated... 

---