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Benzoic acid, peroxide

Synonyms Benzoic acid, peroxide benzoperoxide benzoyl superoxide diphenyl-glyoxal peroxide... [Pg.345]

SYNS ACETOXYL ACNEGEL AZTEC BPO BENOXYL BENZAC BENZAKNEW BENZOIC ACID, PEROXIDE BENZOPEROXIDE BENZOYL BENZOYLPEROXID (GERMAN) BENZOYLPEROXY-DE PUTCH) BENZOYL SUPEROXIDE BZF-60 CADET CADOX CLEARASIL BENZOYL PEROXIDE LOTION CLEARASIL BP ACNE TREATMENT CUTICURA ACNE CREAM DEBROXIDE DIBENZOYLPEROXID (GERMAN) DIBENZOYL PEROXIDE (MAK) DIBENZOYLPEROXYDE PUTCH)... [Pg.149]

BENZOIC ACID NITRILE see BCQ250 BENZOIC ACID, PEROXIDE see BDSOOO BENZOIC ACID, o-(PHENYLHYDROXYARSINO)- see PFKOO... [Pg.1533]

Synonyms cas 94-36-0 acetoxyl acnegel benoxyl benzac benzoic acid, peroxide benzoperoxide benzoyl benzoyl superoxide CLEARASIL BENZOYL peroxide LOTION CLEARASIL BP ACNE TREATMENT CUTICURA ACNE CREAM DEBROXIDE DRY AND CLEAR EPI-CLEAR FOSTEX OXY-5 OXY-10 OXYLITE OXY... [Pg.58]

Benzoic acid, pentyl ester. See Amyl benzoate Benzoic acid peroxide. See Benzoyl peroxide Benzoic acid phenethyl ester. See Phenethyl benzoate... [Pg.445]

Benzaldehyde is easily oxidised by atmospheric oxygon giving, ultimately, benzoic acid. This auto-oxidation is considerably influenced by catalysts tiiose are considered to react with the unstable peroxide complexes which are the initial products of the oxidation. Catalysts which inhibit or retard auto-oxidation are termed anti-oxidants, and those that accelerate auto-oxidation are called pro-oxidants. Anti-oxidants find important applications in preserving many organic compounds, e.g., acrolein. For benzaldehyde, hydroquinone or catechol (considerably loss than U-1 per cent, is sufficient) are excellent anti-oxidants. [Pg.694]

The benzoic acid may be separated by steam distillation or by saturating the aqueous mixture of sodium salts with sulphur dioxide whilst maintaining the temperature below 40° the benzoic acid precipitates and can be separated by filtration or extraction with ether. Acidification of the filtrate with hydrochloric acid liberates the pyruvic acid. The pjTuvic acid may be oxidised < lth hydrogen peroxide to the arylacetic acid, for example ... [Pg.909]

Table 15 shows that peroxyester stabiUty decreases for the alkyl groups in the following order tert — butyl > tert — amyl > tert — octyl > tert — cumyl > 3 — hydroxy — 1,1 dimethylbutyl. The order of activity of the R group in peroxyesters is also observed in other alkyl peroxides. Peroxyesters derived from benzoic acids and non-abranched carboxyUc acids are more stable than those derived from mono-a-branched acids which are more stable than those derived from di-a-branched acids (19,21,168). The size of the a-branch also is important, since steric acceleration of homolysis occurs with increasing branch size (236). Suitably substituted peroxyesters show rate enhancements because of anchimeric assistance (168,213,237). [Pg.130]

Benzoic Acid. Ben2oic acid is manufactured from toluene by oxidation in the liquid phase using air and a cobalt catalyst. Typical conditions are 308—790 kPa (30—100 psi) and 130—160°C. The cmde product is purified by distillation, crystallization, or both. Yields are generally >90 mol%, and product purity is generally >99%. Kalama Chemical Company, the largest producer, converts about half of its production to phenol, but most producers consider the most economic process for phenol to be peroxidation of cumene. Other uses of benzoic acid are for the manufacture of benzoyl chloride, of plasticizers such as butyl benzoate, and of sodium benzoate for use in preservatives. In Italy, Snia Viscosa uses benzoic acid as raw material for the production of caprolactam, and subsequendy nylon-6, by the sequence shown below. [Pg.191]

Pyrogallol monomethyl ether has been prepared by the methylation of pyrogallol with dimethyl sulfate or methyl iodide by the decarboxylation of 2,3-dihj droxy-4-methoxy-benzoic acid and by the methylation of pyrogallol carbonate with diazomethane and subsequent hydrolysis. The method described is taken from the improved procedure of Baker and Savage for the preparation of pyrogallol monomethyl ether from o-vanillin by oxidation with hydrogen peroxide. [Pg.91]

Methylpyridine-l-oxide has been prepared by the oxidation of 3-methylpyridine with hydrogen peroxide in glacial acetic acid, with 40% peracetic acid and sodium acetate, and with per benzoic acid in benzene. ... [Pg.55]

This last result bears also on the mode of conversion of the adduct to the final substitution product. As written in Eq. (10), a hydrogen atom is eliminated from the adduct, but it is more likely that it is abstracted from the adduct by a second radical. In dilute solutions of the radical-producing species, this second radical may be the adduct itself, as in Eq. (12) but when more concentrated solutions of dibenzoyl peroxide are employed, the hydrogen atom is removed by a benzoyloxy radical, for in the arylation of deuterated aromatic compounds the deuterium lost from the aromatic nucleus appears as deuterated benzoic acid, Eq. (13).The over-all reaction for the phenylation of benzene by dibenzoyl peroxide may therefore be written as in Eq, (14). [Pg.138]

Pyridine has been phenylated with the following free-radical sources benzenediazonium chloride with aluminum trichloride the Gomberg reaction " phenylhydrazine and metal oxides A -nitroso-acetanilide dibenzoyl peroxide phenylazotriphenylmethane di-phenyliodonium hydroxide and electrolysis of benzoic acid. ° Although 2-phenylpyridine usually accounts for over 50% of the total phenylated product, each of the three phenyl derivatives can be obtained from the reaction by fractional recrystallization of the... [Pg.143]

In the presence of air, 1,4-dihydrobenzoic acid slowly gives benzoic acid and hydrogen peroxide.2... [Pg.23]

Twenty-two grams (0.45 mole) of 70% hydrogen peroxide (Note 1) is added dropwise with efficient agitation to a slurry or partial solution of 36.6 g. (0.30 mole) of benzoic acid (Note 2) in 86.5 g. (0.90 mole) of methanesulfonic acid (Note 3) in a 500-ml. tail-form beaker. The reaction temperature is maintained at 25-30° by means of an ice-water bath. The reaction is exothermic during the hydrogen peroxide addition, which requires approximately 30 minutes. During this period the benzoic acid completely dissolves. [Pg.93]

In the decomposition of benzoyl peroxide, the fate of benzoyloxy radicals escaping from polarizing primary pairs remains something of a mystery. Benzoic acid is formed but shows no polarization in and C-spectra, and the carboxylic acid produced in other peroxide decompositions behaves similarly (Kaptein, 1971b Kaptein et al., 1972). Some light is shed on the problem by studies of the thermal decomposition of 4-chlorobenzoyl peroxide in hexachloroacetone containing iodine as... [Pg.86]

DPA) in dimethylphthalate at about 70°, yields a relatively strong blue Umax =435 nm) chemiluminescence the quantum yield is about 7% that of luminol 64>. The emission spectrum matches that of DPA fluorescence so that the available excitation energy is more than 70 kcal/mole. Energy transfer was observed on other fluorescers, e.g. rubrene and fluorescein. The mechansim of the phthaloyl peroxide/fluorescer chemiluminescence reaction very probably involves radicals. Luminol also chemiluminesces when heated with phthaloyl peroxide but only in the presence of base, which suggests another mechanism. The products of phthaloyl peroxide thermolysis are carbon dioxide, benzoic acid, phthalic anhydride, o-phenyl benzoic acid and some other compounds 65>66>. It is not yet known which of them is the key intermediate which transfers its excitation energy to the fluorescer. [Pg.81]

Mansouri A, Makris DP and Kefalas P. 2005. Determination of hydrogen peroxide scavenging activity of cinnamic and benzoic acids employing a highly sensitive peroxyoxalate chemiluminescence-based assay structure-activity relationships. J Pharm Biomed Anal 39(l-2) 22-26. [Pg.300]

If we make the assumption that the reverse of reaction 15.5 is diffusion-controlled and assume that the activation enthalpy for the acyl radicals recombination is 8 kJ mol-1, the enthalpy of reaction 15.5 will be equal to (121 - 8) = 113 kJ mol-1. This conclusion helps us derive other useful data. Assuming that the thermal correction to 298.15 K is small and that the solvation enthalpies of the peroxide and the acyl radicals approximately cancel, we can accept that the enthalpy of reaction 15.5 in the gas phase is equal to 113 kJ mol-1 with an estimated uncertainty of, say, 15 kJ mol-1. Therefore, as the standard enthalpy of formation of gaseous PhC(0)00(0)CPh is available (-271.7 5.2 kJ mol-1 [59]), we can derive the standard enthalpy of formation of the acyl radical Af//°[PhC(0)0, g] -79 8 kJ mol-1. This value can finally be used, together with the standard enthalpy of formation of benzoic acid in the gas phase (-294.0 2.2 kJ mol-1 [59]), to obtain the O-H bond dissociation enthalpy in PhC(0)0H DH° [PhC(0)0-H] = 433 8 kJ mol-1. [Pg.222]

Tungsten-catalysed oxidation of alcohols by hydrogen peroxide is achieved in high yield in the presence of tetra-n-butylammonium hydrogen sulphate [20-22]. Secondary alcohols are converted into ketones (>90%) [e.g. 21], but primary alcohols generally are oxidized completely to the carboxylic acids [21], Aldehydes are also oxidized to the carboxylic acids [e.g. 21]. In contrast, using procedure 10.7.8.B, which is adaptable to scale up, benzyl alcohols are converted into the aldehydes benzoic acids are only formed with an excess of hydrogen peroxide [22],... [Pg.462]

Benzoic acid is a by-product of benzoyl peroxide used in the bleaching of freshly milled wheat flour. A maximum benzoic acid concentration of 16 ppm was reported after 12 h of bleaching. The concentration decreased to 6 ppm after 3 months (Saiz et al., 2001). [Pg.143]

Chemical/Physical. In the dark, styrene reacted with ozone forming benzaldehyde, formaldehyde, benzoic acid, and trace amounts of formic acid (Grosjean, 1985). Polymerizes readily in the presence of heat, light, or a peroxide catalyst. Polymerization is exothermic and may become explosive (NIOSH, 1997). [Pg.1007]

Saiz, A.I., Manriqne, G.D., and Fritz, R. Determination of benzoyl peroxide and benzoic acid levels by HPLC during wheat flonr bleaching process. J. Agric. Food Chem., 49(1) 98-102, 2001. [Pg.1718]


See other pages where Benzoic acid, peroxide is mentioned: [Pg.123]    [Pg.167]    [Pg.1008]    [Pg.461]    [Pg.1197]    [Pg.123]    [Pg.167]    [Pg.1008]    [Pg.461]    [Pg.1197]    [Pg.180]    [Pg.37]    [Pg.834]    [Pg.444]    [Pg.154]    [Pg.451]    [Pg.201]    [Pg.690]    [Pg.94]    [Pg.96]    [Pg.248]    [Pg.410]    [Pg.128]    [Pg.219]    [Pg.63]    [Pg.462]    [Pg.143]    [Pg.825]   
See also in sourсe #XX -- [ Pg.58 ]




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