Peroxide adduct

Immediately upon addition of the urea-hydrogen peroxide adduct to the solution containing methyltrioxorhenium, a yellow color develops due to formation of the catalytically active rhenium peroxo complexes.3... 

Urea hydrogen peroxide adduct (UHP) was employed in metal-catalysed asymmetric epoxidation [98] and Baeyer-Villiger oxidation [99,100]. Since the presence of urea does not change the course of the reaction, this will not be described here. Conversion of epoxides to halohydrins with elemental... 

UHP = urea-hydrogen peroxide adduct Balicki. R. Kaczmarek, L. Synth. Commun., 1993, 23, 3149... 

Anderson, L. R. et al., J. Fluorine Chem., 1976, 7, 481-500 Five derivatives, including the 0-0 lithium or sodium salts of the hydrogen peroxide adduct of hexafluoroacetone (2-hydroxyhexafluoro-2-propyl hydroperoxide), and their reaction products with acyl halides, are less flammable or explosive than their hydrocarbon analogues, though less stable than the parent hydroperoxides. Relevant entries are ... 

For the preparation of [l]benzothieno[3,2- ][l]benzofuran-10,10-dioxide 64, hydrogen peroxide in acetic acid, 3-chloroperoxybenzoic acid, and also the urea-hydrogen peroxide adduct with phthalic anhydride were employed. All three methods provided 64 in excellent yields (88-94%). Monitoring the course of the reaction showed the... 

A large number of studies have been published about the mechanism of oxidation of benzene to maleic anhydride, and the structure and role of catalysts and promoters.999,1006 1007 At present hydroquinone formed through a peroxidic adduct is well established to be the intermediate in selective oxidation1008 [Eq. (9.179)], whereas p-benzoquinone is the intermediate in the nonselective oxidation pathway [Eq. (9.180)] ... 

The addition of trifluoroacetic acid to the palladium or platinum peroxide adducts with electrophilic alkenes results in the formation of epoxide in high yield and with high stereoselectivity.143,148 The mechanism shown in equation (51) has been suggested for this reaction.148... 

Styrene derivatives can be selectively converted to the corresponding benzyl alcohols by molecular oxygen in the presence of bis(dimethylglyoximato)chloro(pyridine)cobalt(III) and sodium tetrahydroborate (equation 242).559 A likely mechanism for this reaction involves insertion of the alkene into the cobalt-hydride bond, followed by 02 insertion into the cobalt-carbon bond, as in equation (11), and decomposition of the peroxide adduct (168) to the ketone, which is reduced to alcohol by NaBH4 (equation 243). 

This oxidation, which was developed with ascorbic acid,13 produces D-erythronolactone (4) 14 Hydrogen peroxide is first reduced to water and a hydroxy radical, leading to the formation from 3 of the isoascorbic acid radical 12 The hydroxy radical oxidizes 12 to dehydroisoascorbic acid (13), which in a subsequent step adds hydrogen peroxide. Adduct 14 is than cleaved with base via anion 15 to compound 16. Alkaline hydrolysis of the ester leads to hydroxy acid 17 and the byproduct oxalic acid Subsequent lactonization produces D-erythronolactone (4). 

The starting material (2 mmol) was added to the finely powdered urea-hydrogen peroxide adduct (376 mg, 4 mmol) in a glass test tube, and the reaction mixture was placed in an oil bath at 85 °C. After completion of the reaction, monitored by TLC, the reaction mixture was extracted into ethyl acetate and the combined extracts were washed with water and dried over anhydrous sodium sulfate. The solvent was removed under reduced pressure to afford the crude product, which was purified by chromatography to deliver pure product, as confirmed by the spectral analysis. 

An interesting series of reactions has been developed based on the reaction between Fe(II) and hydrogen peroxide adducts of ketones. The cyclohexanone-hydrogen peroxide adduct10431 b reacts with ferrous sulfate in acidic solutions to produce the 5-carboxypentyl radical.105 In the absence of reactive substrates, dodecanedioic acid is formed by dimerization of these radicals ... 

At least five detailed mechanisms have been proposed for bacterial luciferase within the last six years (28, 47, 48, 49, 50). With the assumption that our biomimetic model relates to the enzyme-catalyzed reaction, we conclude that these five proposals of mechanisms are incorrect. Four (28, 47,48) are inconsistent with the intermediacy of the mixed peroxide (4a-FlEt—O—O—CH(OH)R ) and cannot be applied to N(5)-alkylflavins. In addition, two (28, 47) of these mechanisms as well as another (49), require the hydroxyl group of the aldehyde-peroxide adduct. No mechanism can be taken seriously without the identification of the excited species. We do know that a hydrogen substituted is required on the carbon that is converted to a carbonyl group (47). 

Preliminary resonance Raman spectroscopic characterization of the peroxide adduct of 42 showed two pairs of bands consistent with an... 

Muzart s group has recently described the use of molybdenum catalysts with the hydrogen peroxide adduct, sodium percarbonate and a phase-transfer agent.198 The molybdenum catalyst used in the study was Mo02(acac)2, and the solvents screened were dichloroethane and acetonitrile. The active species is a Mo peroxo complex and in common with other methods based on Mo and W catalysts, secondary, allylic and benzylic alcohols react quickly, and give higher yields of carbonyl product than primary aliphatic alcohols. 

In particular, the reagent avoids the formation of possibly hazardous 2 1 aldehyde-4iydrogen peroxide adducts as well as C—C bond cleavage. Sodium perca nate is an air-stable solid, inexpensive and... 

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