P-Benzoquinone dioxime

Problem 19.33 From phenol prepare (a) p-benzoquinone, (b) p-benzoquinone dioxime, (c) quinhydrone (a 1 1 complex of p-benzoquinone and hydroquinone). 4... 

Figure 7 p-Benzoquinone dioxime cross-linking of butyl rubber. (From Ref. 59.)... 

Oximes. The reaction of p-benzoquinone dioxime, HQN=< =NQH, with nitric oxide in basic methanol solution is reported (8) to produce 2O2N— —N202. The sodium salt of n-butylaldoxime, RCH = NONa,... 

Dioxazine violet B. See Pigment violet 37 Dioxazine violet RL. See Pigment violet 23 1,1 -Dioxide-1,2-benzisothiazol-3(2H)-one sodium salt. See Saccharin sodium anhydrous 1,1-Dioxide tetrahydrothiofuran 1,1-Dioxidetetrahydrothiophene. See Sulfolane Dioxime-p-benzoquinone Dioxime-1,4-cyclohexadienedione Dioxime-2,5-cyclohexadiene-1,4-dione. See p-Quinone dioxime... 

CAS 105-11-3 EINECS/ELINCS 203-271-5 Synonyms p-Benzoquinone dioxime 1,4-Benzoquinone dioxine 2,5-Cyclohexadiene-1,4-dione dioxime Dioxime-p-benzoquinone Dioxime-1,4-cyclohexadienedione Dioxime-2,5-cyclohexadiene-1,4-dione PQD Quinone dioxide p-Quinone oxime Empirical C6H6N2O2 Formula HONC6H4NOH Properties Yel. needles si. sol. in water m.w. 138.06 m.p. 243 C (dec.)... 

Resonance structures can be drawn that show that the polymer backbone from triphenylantimony dichloride and p-benzoquinone dioxime is quite stiff. The product had a low viscosity (6mL/g) but a molecular weight of about 7 x 10 with a LVN/weight average molecular weight of 0.09 x 10". In comparison, polystyrene has a LVN/M of 8 x lO" or about 100 times the antimony product. Polyethylene has a LVN/M value of 35 x 10 or a value about 400 times that of the antimony polymer. Becanse of this stiffness, it is possible that the stiff chain is caught between flow planes rather than residing within a number of flow planes as modest flow occurs. This would result in a greatly decreased viscosity. Second, errors exist because of the possibility that such polymers fluorescence. Thus, this same polymer showed a of 1.5 x 10 before correction for fluorescence. After correction, the was reduced to 7 x 10. Third, anomalous scatter may result from color or absorption. This was tested for the antimony polymer and not found to be a factor. 

Underpotentially deposited ad-atom layers of Pb, Tl, and Bi improve markedly the reversibility of the redox systems hydroquinone/p-benzoquinone [119, 120], pyrocatechol/o-benzoquinone [120], adrenaline/adrenalinequinone [121], hexa-hydroxybenzene/tetrahydroxy-1,4-benzoq-uinone [122], p-benzoquinone dioxime/ p-dinitrosobenzene [123], as well as the... 

DIOXO-2,2,7,9,14,14-HEXAMETHYL- see BIQ660 DIOXATHION see DVQ709 DIOXIME-p-BENZOQUINONE see D R200 DIOXIME-1,4-CYCLOHEXADIENEDIONE see D T1200... 

The aldehyde (50 mmol) and -benzoquinone dioxime (6.90 g, 50 mmol) are dissolved in ethanolic hydrochloric acid (3.5 m, 100 ml). The reaction mixture is then refluxed for several hours until the deep red colour disappears. After cooling, the hydrochloride is filtered off, suspended in ethanol (100 ml), water (200 ml) is added, and the mixture is neutralized with aqueous ammonia. The precipitate is filtered, washed in turn with water and ethanol, and dried. Prepared in this way are the following 1-hydroxybenzimidazole 3-oxides (2-substituent, yield, m.p. listed) Ph, 72%, 223-224°C -Me2NC6H4, 91%, 180-185 C -HOC6H4, 65%, 227-228°C ... 

Benzoquinone. See Quinone Hydroquinone p-Benzoquinone. See Quinone Hydroquinone p-Benzoquinone bis (o-benzoyloxime). See Dibenzoyl-p-quinone dioxime... 

Electrochemical reduction of 1,2-benzoquinone-l,2-dioxime in 2 M sulfuric acid/ethanol (1 1, 0 V) gives a mixture of phenazinc-2,3-diamine (39%), 2-amiiiophenazin-3-ol (6%), and benzene-1,2-diamine (51%). In acetate buffer/ethanol (—0.4 V) only phenazine-2,3-diamine is formed. See also Houben-Weyl, Vol. 4/1 d, p 699. 

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