23-Dimethyl hydroquinone

Figure 12.9 shows the products distribution generated from 2,3-dimethyl-hydroquinone cracking with 80% conversion under two different thermal conditions. Despite its two substituted methyl groups, it followed the same trend as found with hydroquinone, i.e. the product distributions were identical in both cases, which again was different from the chemistry of catechol. A peak of the starting material is found at m/z 136 (dimethylbenzoquinone) and possible identities of other peaks are methylpen-tenyne (m/z 80) and butadiene (m/z 54). 

Dimethyl hydroquinone Nerolin yara yara Bromstyrol... 

Dimethyl hydroquinone Dimethyl resorcinol Dimethyl octanol Dipentene Diphenyl methane Diphenyl oxide Estragol (methyl... 

D-xylose part A, the aromatic part B, and the aliphatic part C, whose starting materials are to be D-xylose, 2,3-dimethyl-/ -hydroquinone, and farnesol. 

Synonyms cas 654-42-2 dmb i,4-dimethoxybenzene dimethyl hydroquinone Hydroxyacetic Acid... 

Todd independently isolated /3-tocopherol from w hcat germ oil, showed that on pyrolysis it yielded trimethyl hydroquinone, and independently synthesized a-tocopherol by condensing phytol with trimethyl hydroquinone he synthesized the three dimethyl toeopherols by condensing phytol with the three dimethyl hydroquinones (Bcrgel et al., 19.38). He also synthesized some cjhromans and coumarans by unambiguous methods and showed that they closely resembled the natural tocopherol. 

Synonyms Anisole, p-methoxy- Benzene, 1,4-dimethoxy- 1,4-Dimethoxybenzene Dimethyl ether hydroquinone Dimethyl hydroquinone Dimethylhydroquinone ether DMB DMHQ HQDME Hydroquinone dimethyl ether p-Methoxyanisole Quinol dimethyl ether Classification Aromatic ether Definition Obtained by methylation of hydroquinone using dimethyl sulfate and alkali Empirical CsHio02 Formula C6H4(OCH3)2... 

Dihydroxy-jp-xylene (2 6-Dimethyl-hydroquinone, hydrophloroae, p-xylohydroquvnone)... 

COCH3 - Preparation by reaction of acetic add on 2,3-dimethyl-hydroquinone with boron trifluoride, followed by saponification of the monoacetate [2909,2994] or OH diacetate [2349] obtained (84-91%) [2349,2994],... 

Chemical Reactivity - Reactivity with Water No reaction Reactivity with Common Materials No reaction Stability During Transport Stabie Neutralizing Agents for Acids and Caustics Not pertinent Polymerization Heat, oxidizing agents, and uitraviolet light may cause polymerization Inhibitor of Polymerization Hydroquinone, 22 - 65 ppm hydroquinone methyl ether, 22 -120 ppm dimethyl tert-butylphenol, 45 - 65 ppm. 

Methylparathion is the corresponding dimethyl derivative. Later (1952) malathion found favour because of its decreased toxicity to mammals it is readily made in 90% yield by the addition of dimethyidithiophosphate to diethylmaleate in the presence of NEtr as a cataly.st and hydroquinone as a polymerization inhibitor ... 

HjC ° ° CH3 2-(2-ominocorbonyl-oxy-1 -methoxyethyl)-5-methyl hydroquinone dimethyl ether... 

CiiHijNO, 3SS4J-4J-7) see Carboquone 2-(2-aminocarbonyloxy-l-methoxyethyl)-S-methyl-hydroquinone dimethyl ether (CjjHiijNOj 38843-63-9) see Carboquone [6U-[6a,7a,7(iJ )])-3-[[(aminocarbonyl)oxyJmethyl]-7-[[5-carboxy-S-[[(4-methylphenyl)sulfonyl]amino]-l-oxo-pentyl]amino]-7-methoxy-8-oxo-5-thia-l-azabicy-clo[4.2.01oct-2-ene-2-carboxylic acid compd. with A-cyclohexylcyclohexanamine (1 1)... 

A strong acceptor TCNE undergoes [2+2] rather than [4+2] cycloaddition reactions even with dienes. 1,1-Diphenylbutadiene [20] and 2,5-dimethyl-2,4-hexadiene (Scheme 5) [21] afford mainly and exclusively vinyl cyclobutane derivatives, respectively. In the reactions of 2,5-dimethyl-2,4-hexadiene (1) the observed rate constant, is greater for chloroform solvent than for a more polar solvent, acetonitrile (2) the trapping of a zwitterion intermediate by either methanol or p-toluenethiol was unsuccessful (3) radical initiators such as benzyl peroxide, or radical inhibitors like hydroquinone, have no effect on the rate (4) the entropies of activation are of... 

Fig. 132.— l/Trr, — l/Tli)/vi plotted against Vi/Tm for mixtures of cellulose tributyrate with hydroquinone monomethyl ether ( ), dimethyl phthalate (O), and ethyl laurate (A). (Mandelkern and Flory. s)... 

The oxidation behavior of 3-oxa-chromanols was mainly studied by means of the 2,4-dimethyl-substituted compound 2,4,5,7,8-pentamethylM /-benzo[ 1,3]dioxin-6-ol (59) applied as mixture of isomers 27a it showed an extreme dependence on the amount of coreacting water present. In aqueous media, 59 was oxidized by one oxidation equivalent to 2,5-dihydroxy-3,4,6-trimethyl-acetophenone (61) via 2-(l-hydroxyethyl)-3,5,6-trimethylbenzo-l,4-quinone (60) that could be isolated at low temperatures (Fig. 6.41). This detour explained why the seemingly quite inert benzyl ether position was oxidized while the labile hydroquinone structure remained intact. Two oxidation equivalents gave directly the corresponding para-quinone 62. Upon oxidation, C-2 of the 3-oxa-chroman system carrying the methyl substituent was always lost in the form of acetaldehyde. 

Diethyl ketone Diethyl phthalate Difluorodibromomethane Diglycidyl ether (DGE) dl Dihydroxybenzene, see Hydroquinone Diisobutyl ketone Diisoctyl phthalate Diisodecyl phthalate Diisononyl phthalate Diisopropyl ether Diisopropylamine Di-linear 79 phthalate Dimethoxymethane, see Methylal Dimethyl acetamide Dimethylamine... 

Hydrazobenzene, d757 Hydrindene, ilO Hydrocinnamic acid, pl50 Hydroquinone, d430 Hydroquinone dimethyl ether, d495 Hydroxyacetanilides, al5 thru al7 Hydroxybenzene, p65 2-Hydroxybenzenemethanol, hl07... 

Anthracyclinones.1 Phthaloyl dichlorides undergo Friedel Crafts reactions with hydroquinones or the dimethyl ethers to give 1,4-dihydroxyanthraquinones in one step. 

The electrolysis apparatus for the polymerization is illustrated in Figure 2, which is characterized by a single cell without a partition membrane between the electrodes. In poor solvents of poly(phenyleneoxide) s such as methanol and acetonitrile, the polymer was deposited on the electrode, i.e. passivation of the electrode occured. Dichlo-romethane, nitrobenzene, and hydroquinone dimethyl ether were selected as the solvents because both the polymer and a supporting electrolyte dissolved in them and they were relatively stable under electrolysis conditions. 

Anodic addition converts enolacetates into a-acetoxyketones or enones, depending on the reaction conditions [135], conjugated dienes into 1,2- or 1,4-dimethoxy alkenes [65], and hydroquinone dimethyl ethers into quinone bisketals [136, 137]. Anodic addition also affords products, some of which are of industrial interest, such as propylene oxide [138a] or 1,4-dimethoxydihydrofuran [138b]. To... 

The bone cement used in these studies was a two-component system. The liquid component [9.75 mL methyl methacrylate (MMA) 0.25 mL A,A-dimethyl-p-toluidine (DMPT) 75 mg/kg hydroquinone] was mixed with a solid component [3.0 g poly(methyl methacrylate) (PMMA) 15.0 g MMA-styrene copolymer benzoyl peroxide, mass fraction 2% 2.0 g BaSOJ to form the cement. Dissolution of the solid component proceeded simultaneously with polymerization once the cement was mixed. 

AI3-00040, see Cyclohexanol AI3-00041, see Cyclohexanone AI3-00045, see Diacetone alcohol AI3-00046, see Isophorone AI3-00050, see 1,4-Dichlorobenzene AI3-00052, see Trichloroethylene AI3-00053, see 1,2-Dichlorobenzene AI3-00054, see Acrylonitrile AI3-00072, see Hydroquinone AI3-00075, see p-Chloro-rrr-cresol AI3-00078, see 2,4-Dichlorophenol AI3-00085, see 1-Naphthylamine AI3-00100, see Nitroethane AI3-00105, see Anthracene AI3-00109, see 2-Nitropropane AI3-00111, see Nitromethane AI3-00118, see ferf-Butylbenzene AI3-00119, see Butylbenzene AI3-00121, see sec-Butylbenzene AI3-00124, see 4-Aminobiphenyl AI3-00128, see Acenaphthene AI3-00134, see Pentachlorophenol AI3-00137, see 2-Methylphenol AI3-00140, see Benzidine AI3-00142, see 2,4,6-Trichlorophenol AI3-00150, see 4-Methylphenol AI3-00154, see 4,6-Dinitro-o-cresol AI3-00262, see Dimethyl phthalate AI3-00278, see Naphthalene AI3-00283, see Di-rj-butyl phthalate AI3-00327, see Acetonitrile AI3-00329, see Diethyl phthalate AI3-00399, see Tributyl phosphate AI3-00404, see Ethyl acetate AI3-00405, see 1-Butanol AI3-00406, see Butyl acetate AI3-00407, see Ethyl formate AI3-00408, see Methyl formate AI3-00409, see Methanol AI3-00520, see Tri-ocresyl phosphate AI3-00576, see Isoamyl acetate AI3-00633, see Hexachloroethane AI3-00635, see 4-Nitrobiphenyl AI3-00698, see IV-Nitrosodiphenylamine AI3-00710, see p-Phenylenediamine AI3-00749, see Phenyl ether AI3-00790, see Phenanthrene AI3-00808, see Benzene AI3-00867, see Chrysene AI3-00987, see Thiram AI3-01021, see 4-Chlorophenyl phenyl ether AI3-01055, see 1.4-Dioxane AI3-01171, see Furfuryl alcohol AI3-01229, see 4-Methyl-2-pentanone AI3-01230, see 2-Heptanone AI3-01231, see Morpholine AI3-01236, see 2-Ethoxyethanol AI3-01238, see Acetone AI3-01239, see Nitrobenzene AI3-01240, see I idine AI3-01256, see Decahydronaphthalene AI3-01288, see ferf-Butyl alcohol AI3-01445, see Bis(2-chloroethoxy)methane AI3-01501, see 2,4-Toluene diisocyanate AI3-01506, see p,p -DDT AI3-01535, see 2,4-Dinitrophenol AI3-01537, see 2-Chloronaphthalene... 

A values have been obtained for oxidation of benzenediols by [Fe(bipy)(CN)4], including the effect of pH, i.e., of protonation of the iron(III) complex, and the kinetics of [Fe(phen)(CN)4] oxidation of catechol and of 4-butylcatechol reported. Redox potentials of [Fe(bipy)2(CFQ7] and of [Fe(bipy)(CN)4] are available. The self-exchange rate constant for [Fe(phen)2(CN)2] has been estimated from kinetic data for electron transfer reactions involving, inter alios, catechol and hydroquinone as 2.8 2.5 x 10 dm moF s (in dimethyl sulfoxide). 

Hodge HC, Sterner JH, Maynard EA, Thomas J Short-term toxicity tests on the mono and dimethyl ethers of hydroquinone.y Ind Hyg Toxicol 31 79-92, 1949... 

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