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Hydrogen peroxide and derivatives

Jones, C.W. (1999) Applications of Hydrogen Peroxide and Derivatives, Royal Society of Chemistry, London. [Pg.555]

Jones, C.W. (1999). Applications of hydrogen peroxide and derivatives. In RSC Clean Technology Monographs, Clark, J.H. (ed.). The Royal Society of Chemistry, Cambridge, UK... [Pg.143]

Applications of Hydrogen Peroxide and Derivatives by C.W. Jones,formerly of Solvay Interox R D, Widnes, UK... [Pg.198]

Conversion of Aromatic Rings to Nonaromatic Cyclic Structures. On treatment with oxidants such as chlorine, hypochlorite anion, chlorine dioxide, oxygen, hydrogen peroxide, and peroxy acids, the aromatic nuclei in lignin typically ate converted to o- and -quinoid stmctures and oxinane derivatives of quinols. Because of thein relatively high reactivity, these stmctures often appear as transient intermediates rather than as end products. Further reactions of the intermediates lead to the formation of catechol, hydroquinone, and mono- and dicarboxyhc acids. [Pg.139]

A number of chemiluminescent reactions may proceed through unstable dioxetane intermediates (12,43). For example, the classical chemiluminescent reactions of lophine [484-47-9] (18), lucigenin [2315-97-7] (20), and transannular peroxide decomposition. Classical chemiluminescence from lophine (18), where R = CgH, is derived from its reaction with oxygen in aqueous alkaline dimethyl sulfoxide or by reaction with hydrogen peroxide and a cooxidant such as sodium hypochlorite or potassium ferricyanide (44). The hydroperoxide (19) has been isolated and independentiy emits light in basic ethanol (45). [Pg.265]

Hydroxyalkyl hydroperoxides having at least one a-hydrogen ie, (7, X = OH, R = alkyll, R = R = H), ie, those derived from aldehydes, lose hydrogen peroxide and form dialkyl peroxides (2, X = Y = OH), especially in the presence of water ... [Pg.112]

Acidic hydrolysis of these hydroxyaLkyl hydroperoxides yields carboxyUc acids, whereas basic hydrolysis regenerates the parent aldehyde, hydrogen peroxide, and often other products. When derived from either aldehydes or cycHc ketones, peroxides (1, X = OH, = H, R, = alkylene or... [Pg.113]

The ease of oxidation varies considerably with the nature and number of ring substituents thus, although simple alkyl derivatives of pyrazine, quinoxaline and phenazine are easily oxidized by peracetic acid generated in situ from hydrogen peroxide and acetic acid, some difficulties are encountered. With unsymmetrical substrates there is inevitably the selectivity problem. Thus, methylpyrazine on oxidation with peracetic acid yields mixtures of the 1-and 4-oxides (42) and (43) (59YZ1275). In favourable circumstances, such product mixtures may be separated by fractional crystallization. Simple alkyl derivatives of quinoxalines are... [Pg.168]

Again, as with pyridopyrimidines, the main reaction is oxidation of di- or poly-hydro derivatives to fully aromatic structures, often merely by air or oxygen. In some cases the reagent of choice is mercury(II) oxide, whilst other reagents used include sulfur, bromine, chloranil, chromium trioxide-acetic acid, hydrogen peroxide, and potassium ferricyanide, which also caused oxidative removal of a benzyl group in the transformation (306) (307)... [Pg.237]

This derivative is prepared in 51-82% yield and is cleaved with Ba(OH)2 or NaOH in 52-96% yield after oxidation of the sulfur with hydrogen peroxide. The derivative is stable to CF COOH and NaOH. ... [Pg.547]

This chemoselectivity stands in contrast to that of 2,6-disubstituted pyridines. For example, 2,6-dimethylpyridine 35 was reacted with hydrogen peroxide and acetic anhydride to produce the expected acetoxy derivative 36. A second iteration of the previous reaction conditions did not afford an aldehyde, as in the previous example, but 2,6-bis-acetoxy derivative 37. [Pg.345]

Ingraffia studied the oxidation of the Grignard reagents derived from indole, skatole, and 2-methylindole with hydrogen peroxide and... [Pg.105]

Oxidation of 2-mercapto-l,2,4-triazolo[l,5-c]pyrimidines (174) with chlorine or bromine in water (64BRP951652 65JCS3369), with hydrogen peroxide and chlorine (95MIP1), as well as with sodium chlorate in hydrochloric acid (94JMC2371) gave the corresponding 2-sulfonyl halide derivatives 175. Oxidation of the 2-alkylmercapto compounds 176 to the 2-alkylsufonyl derivatives 177 was made with ammonium peroxodisulfate and sulfuric acid... [Pg.377]

Tamaoku and colleagues presented an efficient enzymatic photometric determination of hydrogen peroxide ffiat is essentially a color reaction resulting from the oxidative condensation of A/-ethyl-A/-(2-hydroxy-3-sulfopropyl)aniline derivatives wiffi 4-aminoantipyrine in the presence of hydrogen peroxide and peroxidase (82CPB2492). A similar calorimetric detection of hydrogen peroxide has been patented (83GEP3301470). [Pg.144]

The preparation of Pans-1,2-cyclohexanediol by oxidation of cyclohexene with peroxyformic acid and subsequent hydrolysis of the diol monoformate has been described, and other methods for the preparation of both cis- and trans-l,2-cyclohexanediols were cited. Subsequently the trans diol has been prepared by oxidation of cyclohexene with various peroxy acids, with hydrogen peroxide and selenium dioxide, and with iodine and silver acetate by the Prevost reaction. Alternative methods for preparing the trans isomer are hydroboration of various enol derivatives of cyclohexanone and reduction of Pans-2-cyclohexen-l-ol epoxide with lithium aluminum hydride. cis-1,2-Cyclohexanediol has been prepared by cis hydroxylation of cyclohexene with various reagents or catalysts derived from osmium tetroxide, by solvolysis of Pans-2-halocyclohexanol esters in a manner similar to the Woodward-Prevost reaction, by reduction of cis-2-cyclohexen-l-ol epoxide with lithium aluminum hydride, and by oxymercuration of 2-cyclohexen-l-ol with mercury(II) trifluoro-acetate in the presence of ehloral and subsequent reduction. ... [Pg.88]

Analyses for the Saxitoxins. Early methods for analysis of the saxitoxins evolved from those used for toxin isolation and purification. The principal landmarks in the development of preparative separation techniques for the saxitoxins were 1) the employment of carboxylate cation exchange resins by Schantz et al. (82) 2) the use of the polyacrylamide gel Bio-Gel P2 by Buckley and by Shimizu (5,78) and 3) the development by Buckley of an effective TLC system, including a new solvent mixture and a new visualization technique (83). The solvent mixture, designated by Buckley as "E", remains the best for general resolution of the saxitoxins. The visualization method, oxidation of the saxitoxins on silica gel TLC plates to fluorescent degradation products with hydrogen peroxide and heat, is an adaptation of the Bates and Rapoport fluorescence assay for saxitoxin in solution. Curiously, while peroxide oxidation in solution provides little or no response for the N-l-hydroxy saxitoxins, peroxide spray on TLC plates is a sensitive test for all saxitoxin derivatives with the C-12 gemdiol intact. [Pg.47]

WETTASiNGHE M and SHAHiDi F (1999) Evening Primrose Meal A source ofnatural antioxidants and scavenger of hydrogen peroxide and oxygen-derived free radicals, JAgric Food Chem, 47, 1801-12. [Pg.346]


See other pages where Hydrogen peroxide and derivatives is mentioned: [Pg.1123]    [Pg.1123]    [Pg.283]    [Pg.98]    [Pg.283]    [Pg.412]    [Pg.1123]    [Pg.1123]    [Pg.283]    [Pg.98]    [Pg.283]    [Pg.412]    [Pg.293]    [Pg.329]    [Pg.472]    [Pg.481]    [Pg.114]    [Pg.132]    [Pg.294]    [Pg.72]    [Pg.150]    [Pg.147]    [Pg.93]    [Pg.164]    [Pg.180]    [Pg.203]    [Pg.436]   
See also in sourсe #XX -- [ Pg.6 , Pg.7 , Pg.8 , Pg.9 ]




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