P-hydroxybenzene

Synonyms 1,4-Benzenediol 1,4-dihydroxy-benzene p-hydroxybenzene hydroquinol quinol Tecquinol... 

Many oxidative degradations also have been carried out to break coal down into simpler species (10, 18-21) however, isolation and identification of phenols such as p-hydroxybenzene (I), vanillic (II), and syringic (III) derivatives, which are considered as characteristic lignin oxidation products (1, 4, 17, 22, 23), have not yet been confirmed definitely. 

I. -Propanol-pyridine-acetic acid-water (60 40 10 30)+ 1.2 g sodium p-hydroxybenzene sulfonate/140 ml... 

Direct hydroxylation of an aromatic ring to yield a hydroxybenzene (a phenol) is difficult and rarely done in the laboratory., but occurs much more frequently in biological pathways. An example is the hydroxylation of p-hydroxyphenyl acetate to give 3,4-dihydroxyphenyl acetate. The reaction is catalyzed by p-hydroxyphenylacctate-3-hydroxylase and requires molecular oxygen plus the coenzyme reduced flavin adenine dinucleotide, abbreviated FADH2. 

Applications Sollinger and Sawatzki [793] have reported the use of TLC-Raman for routine applications, e.g. TLC of hydroxybenzenes (including hydro-quinone and pyrogallol) on conventional, silica gel and specific Raman-TLC plates (coated with spherical silica gel). Databases were used for identification of substances. Typical detection limits were in the low p,g region per application, Micro-Raman spectrometry has been employed in analysing TLC fractions from polymer additives within a detection limit... 

Synonyms AI3-00150 BRN 1305151 CCRIS 647 4-Cresol p-Cresol p-Cresylic acid EINECS 203-398-6 FEMA No. 2337 l-Hydroxy-4-methylbenzene p-Hydroxytoluene 4-Hydroxytoluene p-Kresol l-Methyl-4-hydroxybenzene 4-Methylhydroxybenzene p-Methyl-hydroxybenzene p-Methylphenol NSC 3696 4-Oxytoluene p-Oxytoluene Paracresol Paramethylphenol RCRA waste number U052 4-Toluol p-Toluol p-Tolyl alcohol UN 2076. 

Synonyms AI3-04856 AIDS-19393 C-00870 BRN 1281877 Caswell No. 603 CCRIS 2316 EINECS 202-811-7 EPA pesticide chemical code 056301 4-Hydroxynitrobenzene p-Hydroxy-nitrobenzene NCI-C55992 4-Nitro-l-hydroxybenzene p-Nitrophenol NSC 1317 PNP RCRA waste number U170 UN 1663. 

Hydrindene, see Indan Hydrindonaphthene, see Indan 1,8-Hydroacenaphthylene, see Acenaphthene Hydrobroinic ether, see Ethyl bromide Hydrocarbon propellant A-17, see Bntane Hydrochloric ether, see Chloroethane Hydrofuran, see Tetrahydrofuran Hydrogen carboxylic acid, see Formic acid Hydrophenol, see Cyclohexanol Hydroqninol, see Hydroquinone Hydroqninole, see Hydroquinone a-Hydroqninone, see Hydroquinone p-Hydroqninone, see Hydroquinone 6-Hydroxyacenaphthenone, see Acenaphthene Hydroxybenzene, see Phenol... 

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... 

Lithium aluminum hydride reduced p-benzoquinone to hydroquinone (yield 70%) [576] and anthraquinone to anthrahydroquinone in 95% yield [576]. Tin reduced p-benzoquinone to hydroquinone in 88% yield [174] Procedure 35, p. 214). Stannous chloride converted tetrahydroxy-p-benzoquinone to hexa-hydroxybenzene in 70-77% yield [929], and 1,4-naphthoquinone to 1,4-di-hydroxynaphthalene in 96% yield [180]. Other reagents suitable for reduction of quinones are titanium trichloride [930], chromous chloride [187], hydrogen sulfide [248], sulfur dioxide [250] and others. Yields are usually good to excellent. Some of the reagents reduce the quinones selectively in the presence of other reducible functions. Thus hydrogen sulfide converted 2,7-dinitro-phenanthrene quinone to 9,10-dihydroxy-2,7-dinitrophenanthrene in 90% yield [248]. 

Selective hydroxylation of phenol with hydrogen peroxide was reported on acid zeolite catalysts [91-92]. Peroxonium ions, formed by H2O2 protonation, are the oxidizing species. When the reaction is carried out on a faujasite catalyst, a mixture of hydroxybenzenes and tars is obtained [91]. In the presence of H-ZSM-5 on the other hand, no tar formation was mentioned (which does not necessarily mean that it was absent) and p-selectivities close to 100% were reported for the hydroxylation [92]. These superior selectivities reflect the shape selective properties of ZSM type zeolites. 

The very significant effect of the presence of a bipolar group on Tb and p L can be nicely seen when comparing hydroxybenzene (phenol) and toluene (Table 4.2). In this case, the difference in Tb ( 70°C) and in p,). (factor of 40 at 25°C) can be attributed primarily to the polar interactions among the phenol molecules because both compounds have similar sizes and a similar specific ability to be engaged in vdW interactions. 

Stolz, J.F., Perera, E., Kilonzo, B., Kail, B., Crable, B., Fisher, E., Ranganathan, M., Wormer, L., Basu, P. (2007). Biotransformation of 3-nitro-4-hydroxybenzene arsonic acid (roxarsone) and release of inorganic arsenic by Clostridium species. Environ. Sci. Technol. 41 818-23. 

SYNS 4-CRESOL p-CRESYLIC acid l-HYDROXY-4-METHYLBENZENE p-HYDROXYTOLUENE 4-HYDROXYTOLUENE p-KRESOL D l-METHYL-4-HYDROXYBENZENE p-METHYLPHENOL 4-METHYLPHENOL p-OXYTOLUENE PARAMETHYL PHENOL RCRA WASTE NUMBER U052 p-TOLUOL p-TOLYL ALCOHOL... 

R)-4-(l-HYDROXY-2-(xMETHYLAMINO)ETHYL)-l,2-BENZENEDIOL (9CI) see VGPOOO (-)-a-HYDROXY-P-(METHYLAMINO)ETHYL-a-(3-HYDROXYBENZENE) HYDROCHLORIDE see SPC500 1 -a-HYDROXY-P-METHYLAi nNO-3-HYDROXY-l -ETHYLBENZENE see NCL500 (R)-3-HYDROXY-a-... 

METHYL-4-HYDROXYBENZENE see CNX250 METHYL-o-HYDROXYBENZOATE see MPIOOO METHYL p-HYDROXYBENZOATE see HJL500... 

Also, antioxidants were found to decrease the aging rate of natural rubber. Among the antioxidants more frequently used are N-phenyl-p-naphthylamine, 2,6-di-tert-butyl-4-methyl-1-hydroxybenzene (BHT), N-isopropyl-N -phenyl-p-phenylenediamine, N-(1,3-dimethylbutyl)-N -p-phenylenediamine, and poly-(2,2,4-trimethyl-1,2-dihydroquinoline). 

Nomenclature chaos in organic chemistry will not be ordered until a one-one correspondence between structure and name is restored. It was with this object specifically in view that a notational system (5) was devised which will generate a unique systematic name in every case. This does not, of course, mean (as some have supposed) that the sole and exclusive use of systematic names for organic substances is advocated. It would be pedantic to talk of hydroxybenzene or 4-hydroxy-l-methylbenzene when phenol or p-cresol is meant. But there must be an agreed, unique systematic or fiducial name for... 

The proposed mechanism [1317,1637,1846] for CO biotransformation by the haem system and cytochrome P-450 (porH = TPPHj or cytochrome P-450 RH, R H = 1,2- hydroxybenzene or nucleophilic groups of microsomal proteins. 

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