Süss-Fink, Georg

2008, Romakh, Vladimir B, Süss-Fink, Georg, Shul'pin, Georgiy B

It was shown that, unlike methane oxidation with the reagent "hydrogen peroxide-vanadate anion-pyrazine-2-carboxylic acid (PCA)" in acetonitrile, the performance of the process in an aqueous solution is accompanied by the intense parallel degradation of the cocatalyst. Therefore, relatively high yields of methane oxidation products (largely, formic acid) cannot be attained unless a rather high PCA concentration is used. Admixtures of a strong acid (sulfuric, trifluoroacetic, or perchloric) increase the yield of the products. It was found that perchloric acid can also be used as a cocatalyst instead of PCA.

2002, Shul'pin, Georgiy B, Süss-Fink, Georg

Osmium derivatives, in particular OsCl3, catalyze the effective oxidation of saturated hydrocarbons in acetonitrile. The products formed are a ketone (aldehyde) and an alcohol. The addition of nitrogen heterocycles, such as pyridine, accelerated the reaction and increased the product yields. The ketone (aldehyde)/alcohol ratio dramatically changed in this case. In the presence of pyridine, the reaction occurred stereoselectively. The suggested reaction mechanism includes hydrogen atom abstraction from an alkane by an osmium oxo compound, resulting in the formation of the alkyl radical, which yields the alkylperoxyl radical after addition of an oxygen molecule. The latter radical degrades in the presence of the osmium complex under reaction conditions to give a ketone (aldehyde) and an alcohol.

2006, Shul'pin, Georgiy B, Sooknoi, Tawan, Romakh, Vladimir B, Süss-Fink, Georg, Shul'pina, Lidia S

Titanosilicalite TS-1 catalyses oxidation of light (methane, ethane, propane and n-butane) and normal higher (hexane, heptane, octane and nonane) alkanes to give the corresponding isomeric alcohols and ketones. The oxidation of higher alkanes proceeds in many cases with a unique regioselectivity. Thus, in the reaction with n-heptane the CH2 groups in position 3 exhibited a reactivity 2.5 times higher than those of the other methylene groups. This selectivity can be enhanced if hexan-3-ol is added to the reaction mixture, the 3-CH2/2-CH2 ratio becoming 10. It is assumed that the unusual selectivity in the oxidation of n-heptane (and other higher alkanes) is due to steric hindrance in the catalyst cavity. As a result, the catalytically active species situated on the catalyst walls can only easily react with certain methylenes of the alkane, which is adsorbed in the cavity taking U-shape (hairpin) conformations. (c) 2006 Elsevier Ltd. All rights reserved.

2002, Süss-Fink, Georg, Shul'pin, Georgiy B

Chromium oxo derivatives (H2CrO4) catalyze the effective oxidation of ethane and other saturated hydrocarbons with hydrogen peroxide or tert-butyl hydroperoxide in an acetonitrile solution at 60degreesC. Alkyl hydroperoxides, ketones (aldehydes), and alcohols are formed as main products. The oxidation of ethane gives ethyl hydroperoxide, acetaldehyde, ethanol, and acetic acid. The turnover frequency reaches 620 h(-1) in this case, and the product yield in terms of H2O2 consumed is 21%.

2005, Shul'pin, Georgiy B, Golfeto, Camilla C, Süss-Fink, Georg, Shul'pina, Lidia S, Mandelli, Dalma

The H2O2-FeCl3-bipy system in acetonitrile efficiently oxidises alkanes predominantly to alkyl hydroperoxides. Turnover numbers attain 400 after 1 h at 60 degrees C. It has been assumed that bipy facilitates proton abstraction from a H2O2 molecule coordinated to the iron ion (these reactions are stages in the catalytic cycle generating hydroxyl radicals from the hydrogen peroxide). Hydroxyl radicals then attack alkane molecules finally yielding the alkyl hydroperoxide. (c) 2005 Elsevier Ltd. All rights reserved.

1997, Süss-Fink, Georg, Yan, Hong, Nizova, Galina V, Stanislas, Sandrine, Shul'pin, Georgiy B

Methane is oxidized in aqueous solution with atmospheric oxygen and hydrogen peroxide in a reaction catalyzed by a NaVO3-pyrazine-2-carboxylic acid system. Methyl hydroperoxide is selectively formed at 50 degrees C. The turnover number of the catalyst after 24 h amounts to 480, and the yield of methyl hydroperoxide is 24% with respect to H2O2. Formaldehyde and formic acid are mainly formed at 120 degrees C.