Inorganic hydroperoxides

High conversions of cyclopentene were obtained by Nuetzel et al. [59] with hydroperoxides, inorganic peroxides, or aromatic nitroderivatives. To increase the stability of some tungsten-based catalytic systems, Witte et al. [63] employed a-halogenated alcohols such as chloroethanol, 2-chlorocyclohexanol, bro-moethanol, l,3-dichloro-2-isopropanol, o-chlorophe-nol, and 2-iodocyclohexanol. It was observed that methyl and ethyl acetals of formaldehyde, acetaldehyde, chloroform, and benzaldehyde impart good staiblity to the binary systems of tungsten, whereas epoxides such as ethylene oxide and butylene oxide lead at the same time to an increase in activity and stability. 

This procedure may result in a concentration of cumene hydroperoxide of 9—12% in the first reactor, 15—20% in the second, 24—29% in the third, and 32—39% in the fourth. Yields of cumene hydroperoxide may be in the range of 90—95% (18). The total residence time in each reactor is likely to be in the range of 3—6 h. The product is then concentrated by evaporation to 75—85% cumene hydroperoxide. The hydroperoxide is cleaved under acid conditions with agitation in a vessel at 60—100°C. A large number of nonoxidising inorganic acids are usehil for this reaction, eg, sulfur dioxide (19). 

Propylene oxide [75-56-9] is manufactured by either the chlorohydrin process or the peroxidation (coproduct) process. In the chlorohydrin process, chlorine, propylene, and water are combined to make propylene chlorohydrin, which then reacts with inorganic base to yield the oxide. The peroxidation process converts either isobutane or ethylbenzene direcdy to an alkyl hydroperoxide which then reacts with propylene to make propylene oxide, and /-butyl alcohol or methylbenzyl alcohol, respectively. Table 1 Hsts producers of propylene glycols in the United States. 

Glutathione peroxidase [9013-66-5] oxidizes glutathione, and helps to remove inorganic and organic hydroperoxides (221] It exhibits antiinflammatory activity in experimental uveitis of rats (234). 

Many types of peroxides (R-O-O-R) are known. Those in common use as initiators include diacyl peroxides (36), pcroxydicarbonatcs (37), peroxyesters (38), dialkyl peroxides (39), hydroperoxides (40), and inorganic peroxides [e.g. persulfate (41)1, Multifunctional and polymeric initiators with peroxide linkages are discussed in Sections 3.3.3 and 6.3.2.1. 

O-O-H (hydroperoxide), ozonides, -C(0)-O-O-H peracids, -0-0- (peroxide), and -0-0-0-connected to inorganic or organic radicals ... 

Horseradish peroxidase (HRP) is a member of the large class of peroxidases, which are enzymes defined as oxidoreductases using hydroperoxide as electron acceptor. HRP has been widely used for the construction of amperometric biosensor for the determination of H202 and small organic and inorganic substrates. 

Copper(II) sulfate Cumene hydroperoxide Cyanides Cyclohexanol Cyclohexanone Decaborane-14 Diazomethane 1,1-Dichloroethylene Dimethylformamide Hydroxylamine, magnesium Acids (inorganic or organic) Acids, water or steam, fluorine, magnesium, nitric acid and nitrates, nitrites Oxidants Hydrogen peroxide, nitric acid Dimethyl sulfoxide, ethers, halocarbons Alkali metals, calcium sulfate Air, chlorotrifluoroethylene, ozone, perchloryl fluoride Halocarbons, inorganic and organic nitrates, bromine, chromium(VI) oxide, aluminum trimethyl, phosphorus trioxide... 

Concerning the mode of formation of ES, we prefer the concept that the substrate in a monolayer is chemisorbed to the active center of the enzyme protein, just as the experimental evidence pertaining to surface catalysis by inorganic catalysts indicates that in these reactions chemisorbed, not physically adsorbed, reactants are involved. Such a concept is supported by the demonstration of spectroscopically defined unstable intermediate compounds between enzyme and substrate in the decomposition by catalase of ethyl hydroperoxide,11 and in the interaction between peroxidase and hydrogen peroxide.18 Recently Chance18 determined by direct photoelectric measurements the dissociation con-... 

Inorganic and organic peroxo compounds, e.g., peroxodisulfates, peroxides, hydroperoxides, peresters Protic acids Proton acceptors Organometallic compounds... 

The transition metal based catalytic species derived from hydrogen peroxide or alkyl hydroperoxides are currently regarded as the most active oxidants for the majority of inorganic and organic substrates " An understanding of the mechanism of these processes is therefore a crucial point in the chemistry of catalytic oxidations. This knowledge allows one to predict not only the nature of the products in a given process, but also the stereochemical outcome in asymmetric reactions. 

The formation of oxenes from hydroperoxides is a rare occurrence, but especially so for simple inorganic compounds such as L1(H20)Cr00H2 +. Recently, some nonheme iron(III) hydroperoxides have been proposed to generate Fe(V) as the active hydroxylating agent for alkanes (111), but direct observation and kinetic characterization of individual steps, such as those in Scheme 1, are still rare. In a recent example, the kinetics of formation of hydroperoxides of Fe(III)- and Mn(III)-microperoxidase-8, their transformation to... 

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