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Oxidation of cumene with 1-methyl-1-phenyl- ethyl hydroperoxide in the presence of copper chloride/ phase transfer catalytic systems was investigated by ESI- MS. For catalytically active copper(II) chloride/crown ethers, copper(II) chloride/crown ethers/alkaline metal salts, and copper(II) chloride/tetrabutylammonium chloride systems, the presence of a few kinds of copper complexes in the organic phase was detected by use of ESI-MS. When copper(II) chloride/podand systems were used, the conversion of hydroperoxide and the yield of oxidation product were close to zero, although the concentration of copper complexes in the organic phase was high. Addition of bis(2-hydroxyethyl) ether to the catalytically active copper(II) chloride/18-crown-6 system resulted in an inhibition effect. Springer-VerIag 2010.

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Glutathione peroxidase (GPx) is an important selenium-containing antioxidant enzyme in human body. The preparation of bionic GPx and the mimicry of its catalytic behavior are of great significance for the development of antioxidant drugs. At present, most of the reported biomimetic selenoenzymes based on the macromolecular are difficult to be degraded, which restricts their applications in the fields such as medical treatment, health care, and functional food. In order to solve this issue, herein, the octenyl succinic acid-modified starch (OSA starch) prepared by the esterification of waxy corn starch was used as the raw material, a new selenium-functionalized starch (Se-starch) was synthesized via the reaction of OSA starch and sodium hydrogen selenide. Such Se-starch, as a biomimetic selenoenzyme, was characterized using 1H NMR, EDS, XPS, SEM, XRD, and FT-IR. The Se-starch with a catalytic activity of 2.48?μM·min?1 showed a typical catalysis behavior of saturated kinetic and enzymology. This catalytic activity is 1.04 × 105 times higher than that of the PhSeSePh, a representative small molecule bionic GPx. The study of catalytic mechanism revealed that the octenyl succinate molecule bonded on the starch endowed it with hydrophobic micro-environments, which benefited the binding of hydrophobic substrates, and consequently increased the catalytic activity. This work not only provided a new idea for constructing natural polymers-based bionic GPx, but also offered an important theoretical basis for the development of new antioxidant drugs and functional foods.

The invention belongs to the technical field of chemical synthesis, and in particular relates to a synthetic method for dialkyl peroxide. The method comprises the following step: adding an alkyl alcohol compound, a compound containing a peroxide bond and a polyvinyl alcohol compound amino acid catalyst into an organic solvent to be stirred and dehydrated to react to synthesize the dialkyl peroxide, wherein the polyvinyl alcohol compound amino acid catalyst is prepared by polymerizing a spherical polyvinyl alcohol matrix and compound amino acids. In a production process of the peroxide, a chemical raw material sulfuric acid or sodium hydroxide with certain corrosion is avoided, the synthetic process of the peroxide is optimized, and the waste water discharge containing sulfuric acid or sodium hydroxide in the industrial production process is reduced.

The invention relates to a method for co-production of epoxide and dicumyl peroxide to mainly solve the problems of the prior art that a large amount of wastewater and offscum containing chlorine and sulphur is generated, pollution is serious, product quality is poor, energy consumption is high, production efficiency is low, and labor intensity is high. The method comprises the steps that a, cumyl hydroperoxide and olefin react, and reaction products are separated to obtain epoxide and alpha, alpha-dimethyl benzyl alcohol; b, cumyl hydroperoxide reacts with alpha, alpha-dimethyl benzyl alcohol generated in the step a to generate dicumyl peroxide. The method can be used for industrial co-production of epoxide and dicumyl peroxide.

Process for the preparation of hydroperoxides of alkylbenzenes characterized by the fact that the alkylbenzene reacts with oxygen in the presence of a catalytic system which includes an N-hydroxyimide or an N-hydroxysulfamide and a polar solvent.

A method for the production of phenol and acetone from a cumene hydroperoxide mixture comprises: decomposing the cumene hydroperoxide mixture in the presence of a catalyst mixture to form a mixture comprising phenol and acetone, wherein the method further comprises: a) forming the catalyst mixture in a catalyst formation reactor by combining sulfuric acid and phenol in a weight ratio of from 2:1 to 1:1000; b) holding the catalyst mixture in the catalyst formation reactor at a temperature of about 20 to 80° C. for about 1 to 600 minutes; and c) adding the catalyst mixture to the cumene hydroperoxide mixture to form the phenol and acetone mixture. Running the process in this manner reduces the yield of hydroxyacetone and, consequently, improves the quality of the commercial phenol. Moreover, this method reduces consumption of sulfuric acid in comparison with the process in which sulfuric acid is used as catalyst.

A lithographic printing plate precursor comprising a support and an image-recording layer containing at least one infrared absorbing agent of a cyanine dye in which a HOMO energy level of each of substituents present on both terminal nitrogen atoms is -10.0 eV or higher. An infrared absorbing agent of a cyanide dye represented by formula (V) shown below: wherein Z 1 and Z 2 each independently represents an aromatic ring which may have a substituent or a hetero aromatic ring which may have a substituent; R 10 and R 20 each independently represents a phenyl group, a naphtyl group, an anthracenyl group, a carbazolyl group or a phenothiazinyl group each of which may have a substituent; A - represents an anion which exists in case of being necessary for neutralizing a charge and is selected from a halogen ion, a perchlorate ion, a tetrafluoroborate ion, a hexafluorophosphate ion and a sulfonate ion; and n represents 1 or 2.

The reactivity of neurotransmitters toward hydrogen abstraction by an active oxygen species (the cumylperoxyl radical) is comparable to that of a strong antioxidant such as catechin due to the strong intramolecular hydrogen bonding, which has been successfully detected by ESR. The Royal Society of Chemistry 2006.

Evidence for phase transfer catalysis in the oxidation of cumene with 1- methyl-1-phenylethylhydroperoxide to bis-(1-methyl-1-phenylethyl)peroxide in the presence of copper salt - crown ether catalysts is given.

The SNAr reaction of sodium cumyl peroxide with selected haloaromatic compounds under phase transfer catalysis conditions has been studied. Corresponding phenols have been obtained. The mechanism of the reaction has been proposed. Key words: SNAr, nucleophilic aromatic substitution, PTC, phenols, peroxides

The cobalt(II) naphthenate catalyzed decomposition of cumene hydroperoxide (CHP) gave a mixture of α-cumyl alcohol, acetophenone and di-α-cumyl peroxide in benzene at 25 deg C.All experimentally observed time courses of disappearing CHP and an increasing of three products compared well with theoretical values.

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In the acid-catalyzed decomposition of cumene hydroperoxide in phenol-acetone medium the formation of dicumyl peroxide is due to the reaction of dimethylphenylcarbinol with isopropylbenzene hydroperoxide by a mechanism that excludes carbenium ion.The formation of dicumyl peroxide by isopropylbenzene is reversible. Decomposition of isopropylbenzene hydroperoxide in phenol-acetone at low acidity increases the yield of dicumyl peroxide.At high acidity the yield of α-methylstyrene dimers and complex phenols increases.

Liquid organic peroxidic compositions suitable for the crosslinking of polyolefins compositions contain (a) from 1 to 50 parts by weight of a diperoxide of the formula: (in which the substituent groups of the central ring A are in the meta and/or power positions) (b) from 5 to 75 parts by weight of dicumyl peroxide; and (c) from 1 to 85 parts by weight of a peroxide of the formula: in which R is H or C1-C3 alkyl group; and A is a methyl phenyl or substituted phenyl group.

A process for the preparation of an ester of dicarboxylic acid from an alkene, carbon monoxide. The process is catalyzed by a catalyst which comprises a platinum group metal, for example palladium, and a copper compound. To avoid catalyst deactivation the process is carried out in the presence of a dihydrocarbyl peroxide which is reduced to a hydrocarbyl alcohol under the process conditions. The process can be used, for example, to prepare succinate esters from ethylene, carbon monoxide, an alcohol and a dihydrocarbyl peroxide such as di-tertiary butyl peroxide.

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A process for the preparation of dicumyl peroxide by reaction of dimethylbenzyl hydroperoxide (cumene hydroperoxide) with methyl cumyl ether is described. The reaction is carried out in the presence of a catalytic quantity of Lewis or Bronsted acids, the methanol which forms as a by-product being removed as the reaction proceeds. Furthermore, the reaction is carried out in a reaction medium consisting of the methyl cumyl ether itself, which is employed in quantities greater than the stoichiometric quantity required for the reaction with the cumene hydroperoxide.

Cumyloxy (1-methyl-1-phenylethoxy) radicals have been generated by thermolysis (60 deg C) of dicumyl hyponitrite in methyl methacrylate and styrene.The carbon-centred radicals formed by interaction of cumyloxyl with the respective monomers were trapped as stable adducts of 1,1,3,3-tetramethylisoindolin-2-yloxyl.Extensive hydrogen atom abstraction and methyl radical generation as well as double-bond addition were observed in methyl methacrylate.Styrene underwent only double-bond addition by both cumyloxy and methyl radicals.Some possible implications of these results for polymer structure are discussed.A kinetic study of the decomposition of dicumyl hyponitrite in cyclohexane at various temperatures gave k=7.7*1014exp(-13600/T) s-1 for the rate constant.Rate constants for the addition of cumyloxyl to methyl methacrylate (k ca.2*104 dm3mol-1s-1) and styrene (k ca. 2*105dm3mol-1s-1) at 60 deg C have been estimated

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Although it is generally accepted that the self-reaction of cumylperoxy radicals is a second-order process, recent reports have cast doubt on the overall validity of this assumption.Therefore we have reinvestigated some aspects of the self-reaction to clarify the kinetic and mechanistic features.Our product studies are entirely consistent with the accepted mechanism for the self-reaction of cumylperoxy radicals and no evidence was obtained for competing reactions.Results obtained with 36O2 labelled materials confirm the previous conclusion that reversible scission of cumylperoxy radicals to give oxygen and cumyl radicals does not compete significantly with the self-reaction at ambient temperatures.Kinetic studies, under both steady-state and transient conditions, establish clearly that the self-reaction of cumylperoxy radicals is a second order process.A possible explanation is proposed to account for the previous observations which indicated that the self-reaction was a first order process.Further, we show that the changes observed in the esr spectrum of the cumylperoxy radicals, which were attributed to the formation of a complex with cumylhydroperoxyde, are caused by changes in the viscosity of the solution.

An olefin such as α-methylstyrene or a substituted α-methylstyrene, wherein the substituent is on the phenyl ring, a t-cumyl halide corresponding to the hydrohalogenated olefin or a substituted t-cumyl chloride and hydrogen peroxide are reacted under relatively non-aqueous conditions, in the absence of a free acid and in the presence of a phenol, to obtain a symmetrical dicumyl (or substituted dicumyl) peroxide which is useful as cross-linking agents for polyethylene and elastomers.

The decomposition of 7-cumyl hydroperoxide and tert-butyl hydroperoxide on iron or cobalt phthalocyanine in 1-chloronaphthalene, 1-bromonaphthalene and 3-chlorotoluene proceeds with evolution of oxygen and according to second order kinetics (Figures 2 and 3; Tables 1 - 3 and 7); the yield of oxygen is not quantitative (Figure 1, Tables 1 - 3 and 7).Evolution of oxygen is not observed in 1-methylnaphthalene and decalin. - In the presence of N-(2-naphthyl)aniline the oxygen yield decreases with increasing concentration of the inhibitor (Table 4).The inhibitor efficiency is influenced by substituents in the phenyl group (Table 5), a Hammett relation being fulfilled in the case of 3-Cl and 4-Cl or CH3O (Figure 4). - 2-Benzyl-2-propyl hydroperoxide decomposes without evolution of oxygen.The decomposition rate on cobalt phthalocyanine is influenced by the composition of the solvent systems (1-chloronaphthalene/decalin, 1-chloronaphthalene/3-chlorotoluene, 3-chlorotoluene/decalin) (Table 6). - The mechanism of the decomposition of the hydroperoxides, especially the stabilizing reactions of the radicals, and the attack of the inhibitors is discussed in the light of previous results.

An aliphatic or cycloaliphatic hydroperoxide, an olefin such as a 1-aromatic-1-substituted ethylene and a halide corresponding to the ethylene are reacted under essentially anhydrous conditions, in the absence of a free acid, at a temperature below the decomposition temperature of the halide to obtain a peroxide corresponding to the hydroperoxide and the ethylene. Preferably the product peroxide is recovered by treating the reaction product mixture with aqueous alkali metal hydroxide to destroy the halide and hydroperoxide therein; then distilling the treated mixture in the presence of a substantial amount of liquid water at sub-atmospheric pressure to remove overhead impurities. Example: Dicumyl peroxide is prepared by reacting at about 30° C. for about 5 hours cumene hydroperoxide, α-methylstyrene and cumyl chloride, which compounds has been charged to the reaction zone in a mole ratio of 1.25:0.86:0.14 and treating the reaction product mixture with aqueous alkali metal hydroxide to remove cumyl chloride and cumene hydroperoxide to obtain a product mixture including dicumyl peroxide; and adding 2-10 parts of liquid water to the product mixture in a distillation zone and vaporizing water and impurities at a temperature of about 30°-80° C. at a pressure of about 0.01-0.5 atmospheres and continuing said vaporization until essentially no oily liquid is obtained in a condensor receiving vapors from said zone, under conditions such that a substantial amount of liquid water is present in said zone in contact with peroxide product.

An aliphatic or cycloaliphatic hydroperoxide or aliphatic dihydroperoxide, an olefin such as alpha-methylstyrene or a substituted alpha-methylstyrene wherein the substituent is on the phenyl ring and a t-cumyl halide corresponding to the hydrohalogenated olefin such as t-cumyl chloride or a substituted t-cumyl chloride are reacted under relatively non-aqueous conditions, in the absence of a free acid and in the presence of a phenol catalyst, to obtain a cumyl (or substituted cumyl) peroxide or diperoxide corresponding to the hydroperoxide or dihydroperoxide. The cumyl peroxides prepared by this reaction are very useful as crosslinking agents for polyethylene and elastomers.

The reaction of Martin's sulfurane 1 with tert-butyl hydroperoxide, in the presence of 9,10-dibromoanthracene, emits light in two stages.The early stage, beginning on warming to about -40 deg C, coincides with the formation of olefin, and is intensified by degassing and quenched by oxygen or by organic sulfides.The later stage, seen on warming from -20 to -10 deg C, occurs during the formation of acetone from the hydroperoxide; this luminescence is eliminated by degassing and quenched by 2,6-di-tert-butyl-p-cresol and organic sulfides.Similar phenomena are observed with cumyl hydroperoxide.Relevant observations are reported on the NMR shifts produced in alcohol proton signals by diphenyl sulphoxide and dimethyl sulfoxide and on the CIDNP signals occurring during the reaction.Some conclusions are drawn concerning the mechanism of the luminescence.

This invention relates to an improved method for the production of high purity dicumyl peroxide. As produced, dicumyl peroxide contains many impurities which must be removed. Generally, our invention comprises flash distilling crude dicumyl peroxide, separating and discarding the distillate and allowing the residual product to crystallize. The supernatant liquid from the crystallized dicumyl peroxide is then fed into the next batch of crude dicumyl peroxide to be distilled. In this manner high yields are obtained along with a very rapid distillation time. Because the supernatant liquid from each crystallization is fed back into the process, the dicumyl peroxide normally left in the supernatant is recovered in the subsequent steps.

Tetraperoxides of the formula EQU1 where X is a bivalent radical such as alkylene; R1 is hydrogen or an organic radical; R2 is alkylene alkoxy carbonyl; and R3 is an organic radical. Method of preparing tetraperoxides by addition reaction between a bis-hydroperoxide and a carbonyl compound to form a dihydroxy diperoxide, followed by condensation of the dihydroxy diperoxide with a tertiary monohydroxide. The tetraperoxides are useful for vulcanizing saturated elastomers, crosslinking plastomers, and initiating radical polymerization.