Oxidation, aerobic manganese -catalyzed

Manganese appears to be unique in catalyzing 02 evolution in all aerobic pho-totrophs. No other metal ion has been found to date that can replace it. Manganese was probably selected via evolution for this function because of its ability to exist in multiple oxidation states (Mn2+, Mn3+, Mn4+, Mn5+) and to form strong bonds with oxygen ligands [29],... 

Some microorganisms can catalyze certain oxido-reduction reactions like the oxidation of iron and manganese in water, the oxidation of sulfur compounds, and oxidation-reduction of nitrogen compounds. Aerobic autotrophic bacteria of the type Thiobacillus can release soluble iron, copper, and sulfuric acid as sulphates into water. These organisms can be found everywhere in nature wherever an acidic environment is maintained in the presence of sulfide-containing minerals. 

Abstract Synthesis of endoperoxides and hydroperoxides using tris(2,4-pentanedionato) manganese(IIl) or manganese(III) acetate is described. The reaction of various alkenes with tris(2,4-pentanedionato)manganese(lll) at ambient temperature in air gives 4-acetyl-l,2-dioxan-3-ols. The manganeseflll) acetate-catalyzed aerobic oxidation of various al-... 

Scheme 21 Manganese(III)-catalyzed aerobic oxidation of 4-piperidone-3-carboxylates in the presence of alkenes...

Dioxan-3-ol derivatives are formed at ambient temperature during the aerobic oxidation catalyzed by the Mn(II)-Mn(III) redox system. The manganese(III)-enolate complex A would be formed by the reaction of... 

Scheme 31 Mechanism of the manganese(III)-catalyzed aerobic oxidation...

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