Hydrogen peroxide iron oxidation chemistry

Figure 60. Christian Friedrich Schonbein (1799-1868). (Courtesy E. Berl.) Discovered guncotton, 1846. Discovered ozone, worked on hydrogen peroxide, auto-oxidation, the passivity of iron, hydrosulfites, catalysts, and prussic acid. Professor of Chemistry at Basel from 1829 until the time of his death. He published more than 300 papers on chemical subjects. Reproduced from original in Kekule s portrait album.

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. ... 

Although most iron(II) complexes are oxidized by hydrogen peroxide (HOOH) via Fenton chemistry,... 

Recently, iron catalysis gained general importance. Its catalytic chemistry has been summarized ([2] recent reviews [3, 4]). Iron(II) and iron(III) salts have a long history in radical chemistry. The former are moderately active in atom-transfer reactions as well as initiators for the Fenton reaction with hydrogen peroxide or hydroperoxides (reviews [5-12]). Important applications of this principle are the Kharasch-Sosnovsky reaction (the allylic oxidation of olefins) [13], which often... 

It should be pointed out that even if one starts with a single oxidation state of iron in the presence of hydrogen peroxide, both states are soon produced. The ferric ion can oxidize perhydroxyl radical (H02) and/or its conjugate ion (02 ), as well as hydrogen peroxide. The chemistry of iron(III) with hydrogen peroxide has been comprehensively reviewed by Brown, Jones and Suggett.28... 

Radical nucleophile oxidation based on one-electron oxidation, known as the Minisci reaction, is employed for the functionalization of /V-heterocycles with acidic hydrogen peroxide in the presence of iron(II) salts (Figure 3.112).472 A range of A-heterocycles (pyridines, pyrazines, quinolines, etc.) which are activated towards attack by nucleophilic radicals when protonated are suited to this chemistry. The Minisci reaction is suitable for the preparation of carboxylic amides (from formamide), carboxylic esters (from pyruvic esters via a hydroxyhydroperoxide), aldehydes (from 1,3,5-trioxane) and alkylated pyridines (either from carboxylic acids or from alkyl iodides in dimethyl sulfoxide).473 The latter reaction uses dimethyl sulfoxide as the source of methyl radical (Figure 3.112). 

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