Alkanes manganese catalysts

Manganese(III) acetate is poorly reactive with saturated hydrocarbons.514 However, oxidation of adamantane by Mn(OAc)3 in trifluoroacetic acid gives relatively high yields of 1-adamantyl trifluoroacetate, showing a preferential attack at tertiary C—H bonds.515 Oxidation of n-alkanes by air in the presence of manganese catalysts constitutes the basis for an industrial process for the manufacture of synthetic fatty acids from n-alkanes of petroleum origin, which has been commercially developed in the Soviet Union.516... 

It is likely that some of the mechanisms that we discussed are operational in parallel, and there are data that confirm this view. It is experimentally observed that the primary alkene alkane molar ratio seems to be in the range between 2 and 4. A value of 4 has been found for reaction on an iron-manganese catalyst operating at 550 K (107), on a precipitated cobalt catalyst operating at 463 K (108), and on a Ru/Si02 catalyst operating at 483 K (109). 

S. Tangestaninejad, M. H. Habibi, V. Mirkhani, M. Moghadam, Manganese(III) porphyrin supported on polystyrene as a heterogeneous alkene epoxidation and alkane hydroxylation catalyst, Synth. Commun. 32 (2002) 3331. 

The insertion of oxygen into a C-H-bond via allylic oxidation or alkane oxidation is a difficult reaction and not many efficient methods are known in the literature [32]. Recently, a fluorinated manganese catalyst solubilized in a perfluorinated solvent has found application in the oxidation of cyclohexene to cyclo-hexenol and cyclohexenone [33, 34]. As catalyst precursor the manganese salt of... 

The present review has outlined the efforts to develop biomimetic non-heme iron and manganese catalysts for alkane hydroxylation, olefin epoxidation, and cis-dihydroxylation reactions. However, the examples reviewed here are mostly presented as reported in the literature, since the various reaction conditions involved in the catalytic oxidations hamper a direct comparison and critical evaluation of the data. The survey has not only illustrated a rich variety of iron and manganese complexes that lead to the successful structural modeling of important non-heme iron and manganese enzymes, but also significant features of the oxidation reactions catalyzed by these complexes in combination with dihydrogen peroxide. 

Manganese Catalysts for the Oxidation of Alkanes, Alcjohols, and Aldehydes... 

Amination of alkanes (cyclohexane, heptane, adamantane) was achieved with iron and manganese porphyrin catalysts by tosylimidoiodobenzene to yield tosyl-amino derivatives.200 Selective 1-substitution of adamantane (56% yield) and 2-substitution of heptane (66% selectivity) were reported. 

Barloy, L., Lallier, J. P., Battioni, P., Mansuy, D., Piffard, Y Tournous, M., Yalim, J. B. and Jones, W. (1992). Manganese porphyrins adsorbed or intercalated in different mineral matrices - preparation and compared properties as catalyst for alkene and alkane oxidation. New J. Chem. 16, 71. 

Air oxidation of /i-butane to maleic anhydride is possible over vanadium phos(4tate and, remaiicably, a 60% selectivity is obtained at 85% conversion. In the gas phase oxidation, in conffast to the situation found in the liquid, n-allcanes are oxidized more rapidly than branched chain alkanes. This is because secondary radicals are more readily able to sustain a chain for branched alkanes the relatively stable tertiary radical is preferentially formed but fails to continue the chain process. Vanadium(V)/ manganese(II)/AcOH has been used as a catalyst for the autoxidation of cyclohexane to adipic acid, giving 25-30% yields after only 4 h. ... 

A further report of the oxidation ability of manganese nodules is that of Nitta.53 Several reactions were carried out with natural manganese oxide nodules including oxidative dehydrogenations of alkanes and cycloalkanes, reduction of NO, total oxidation of CO, and use in the gettering of metal and mixed metal ions. For example, nodules were found to have a tremendous capacity for adsorption of heavy metals and toxic metals like Pb2+, and Hg2+. in addition, nodules have been used to sequester metals that are present in petroleum fractions that can contain metals like V and Ni. These metals can cause degradation of the fluid cracking catalysts even at levels as low as 1 ppm. 

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