Hydrogen peroxide hydroxylamine oxidation

In addition to mimicking the function of the enzyme reasonably well, this system may provide some insight into the inactivation of the Mn catalase by the mixture of hydroxylamine and hydrogen peroxide. It is known that hydroxylamine is a hydrogen peroxide mimic as a re-ductant of the Mn catalase. However, unlike hydrogen peroxide, hydroxylamine reduces the enzyme by only one electron. If this is done in the Mn(III,III) oxidation level, an intermediate Mn(II,III) enzyme is... 

Isatin (190) is a compound with interesting chemistry. It can be iV-acetylated with acetic anhydride, iV-methylated via its sodium or potassium salt and O-methylated via its silver salt. Oxidation of isatins with hydrogen peroxide in methanolic sodium methoxide yields methyl anthranilates (81AG(E)882>. In moist air, O-methylisatin (191) forms methylisatoid (192). Isatin forms normal carbonyl derivatives (193) with ketonic reagents such as hydroxylamine and phenylhydrazine and the reactive 3-carbonyl group also undergoes aldol condensation with active methylene compounds. Isatin forms a complex derivative, isamic acid (194), with ammonia (76JCS(P1)2004). 

The most widely employed methods for the synthesis of nitrones are the condensation of carbonyl compounds with A-hydroxylamines5 and the oxidation of A+V-di substituted hydroxylamines.5 9 Practical and reliable methods for the oxidation of more easily available secondary amines have become available only recently.10 11 12 13. These include reactions with stoichiometric oxidants not readily available, such as dimethyldioxirane10 or A-phenylsulfonyl-C-phenyloxaziridine,11 and oxidations with hydrogen peroxide catalyzed by Na2W044 12 or Se02.13 All these methods suffer from limitations in scope and substrate tolerance. For example, oxidations with dimethyldioxirane seem to be limited to arylmethanamines and the above mentioned catalytic oxidations have been reported (and we have experienced as well) to give... 

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... 

Acyl nitroso compounds (3, Scheme 7.2) contain a nitroso group (-N=0) directly attached to a carbonyl carbon. Oxidation of an N-acyl hydroxylamine derivative provides the most direct method for the preparation of acyl C-nitroso compounds [10]. Treatment of hydroxamic acids, N-hydroxy carbamates or N-hydroxyureas with sodium periodate or tetra-alkyl ammonium periodate salts results in the formation of the corresponding acyl nitroso species (Scheme 7.2) [11-14]. Other oxidants including the Dess-Martin periodinane and both ruthenium (II) and iridium (I) based species efficiently convert N-acyl hydroxylamines to the corresponding acyl nitroso compounds [15-18]. The Swern oxidation also provides a useful alternative procedure for the oxidative preparation of acyl nitroso species [19]. Horseradish peroxidase (HRP) catalyzed oxidation of N-hydroxyurea with hydrogen peroxide forms an acyl nitroso species, which can be trapped with 1, 3-cyclohexanone, giving evidence of the formation of these species with enzymatic oxidants [20]. 

The bis-hydroxylamine adduct [Fe (tpp)(NH20H)2] is stable at low temperatures, but decomposes to [Fe(tpp)(NO)] at room temperature. [Fe(porphyrin)(NO)] complexes can undergo one-and two-electron reduction the nature of the one-electron reduction product has been established by visible and resonance Raman spectroscopy. Reduction of [Fe(porphyrin)(NO)] complexes in the presence of phenols provides model systems for nitrite reductase conversion of coordinated nitrosyl to ammonia (assimilatory nitrite reduction), while further relevant information is available from the chemistry of [Fe (porphyrin)(N03)]. Iron porphyrin complexes with up to eight nitro substituents have been prepared and shown to catalyze oxidation of hydrocarbons by hydrogen peroxide and the hydroxylation of alkoxybenzenes. ... 

Bipositive polonium in hydrochloric acid solution (pink) is oxidized to polonium(lV) by hydrogen peroxide, by hypochlorous acid or by the radiolysis products of the alpha bombardment of the solvent. Solutions of polonium(II) in acid are obtained by the reduction of polonium(lV) with sulfur dioxide or hydrazine in the cold, or with arsenious oxide on warming. Polonium (IV) is not reduced in hydrochloric acid by either hydroxylamine or oxalic acid, even on boiling 6). 

Fluoro-2.2-dinitroethyl)aniine is not affected by hydrogen peroxide in aqueous or methanolic solution, even in the presence of transition metal catalysts.218 On the other hand, it is oxidized by 3-chloroperoxybenzoic acid to the corresponding hydroxylamine 8, which on further oxidation by a second equivalent of the peroxy acid or bromine gives an oxime (vide infra).118... 

Nitroso-/ -phenylhydroxylamine, of which cupferron is the ammonium salt, has been made by the action of sodium nitrite and hydrochloric acid on /3-phenylhydroxylamine,1 of hydrogen peroxide on normal phenyldiazotates,2 of sodium alcoholate and hydroxylamine on nitrobenzene,3 of nitric oxide on phenyl magnesium bromide,4 and by the action of permonosulfuric acid on aniline in the presence of amyl nitrite.5... 

Cyclodextrin ketones have been used as powerful catalysts of amine oxidation in the presence of hydrogen peroxide as the stoichiometric oxidant. This oxidation follows Michaelis-Menten kinetics and depending on the substrate the oxidation rate is increased up to 1100-fold. It has been proposed that hydrogen peroxide reacts with the ketone to form a hydroperoxide adduct and this adduct is responsible for oxidizing the amine, bound in the cavity, to the hydroxylamine.189... 

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