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Süss-Fink, Georg

Nom
Süss-Fink, Georg
Affiliation principale
Fonction
Professeur ordinaire
Email
georg.suess-fink@unine.ch
Identifiants
https://libra.unine.ch/handle/123456789/385

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  • Publication
    Métadonnées seulement
    Hydrogen peroxide oxygenation of alkanes including methane and ethane catalyzed by iron complexes in acetonitrile
    (2004)
    Shul'pin, Georgiy B
    ;
    Nizova, Galina V
    ;
    Kozlov, Yuriy N
    ;
    Gonzalez-Cuervo, Laura
    ;
    Süss-Fink, Georg 
    This paper describes an investigation of the alkane oxidation with hydrogen peroxide in acetonitrile catalyzed by iron(III) perchlorate (1), iron(III) chloride (2), iron(III) acetate (3) and a binuclear iron(III) complex with 1,4,7-triazacyclononane (4). The corresponding alkyl hydroperoxides are the main products. Nevertheless in the kinetic study of cyclohexane oxidation, the concentrations of oxygenates (cyclohexanone and cyclohexanol) were measured after reduction of the reaction solution with triphenylphosphine (which converts the cyclohexyl hydroperoxide to the cyclohexanol). Methane and ethane can be also oxidized with TONs up to 30 and 70, respectively. Chloride anions added to the oxidation solution with 1 activate the perchlorate iron derivative in acetonitrile, whereas the water as additive inactivates 2 in the H2O2 decomposition process. Pyrazine-2-carboxylic acid (PCA) added to the reaction mixture decreases the oxidation rate if 1 or 2 are used as catalysts, whereas compounds 3 and 4 are active as catalysts only in the presence of small amount of PCA. The investigation of kinetics and selectivities of the oxidations demonstrated that the mechanisms of the reactions are different. Thus, in the oxidations catalyzed by the 1, 3+PCA and 4+ PCA systems the main oxidizing species is hydroxyl radical, and the oxidation in the presence of 2 as a catalyst has been assumed to proceed (partially) with the formation of ferryl ion, (Fe-IV=O)(2+). In the oxidation catalyzed by the 4+PCA system (TONs attain 240) hydroxyl radicals were generated in the rate-determining step of monomolecular decomposition of the iron diperoxo adduct containing one PCA molecule. A kinetic model of the process which satisfactorily describes the whole set of experimental data was suggested. The constants of supposed equilibriums and the rate constant for the decomposition of the iron diperoxo adduct with PCA were estimated.
  • Publication
    Métadonnées seulement
    Hydroperoxidation of methane and other alkanes with H2O2 catalyzed by a dinuclear iron complex and an amino acid
    (2002)
    Nizova, Galina V
    ;
    Krebs, Bernt
    ;
    Süss-Fink, Georg 
    ;
    Schindler, Siegfried
    ;
    Westerheide, Lars
    ;
    Gonzalez-Cuervo, Laura
    ;
    Shul'pin, Georgiy B
    The compound [Fe-2(HPTB)([mu-OH)(NO3)(2)](NO3)(2).CH3OH.2H(2)O (1) containing a dinuclear iron(III) complex in which HPTB=N,N,N',N'-tetrakis(2-benzimidazolylmethyl)-2-hydroxo-1,3-diaminopro pane catalyzes the oxidation of alkanes with hydrogen peroxide in acetonitrile solution at room temperature only if certain amino acids (pyrazine-2-carboxylic, pyrazine-2,3-dicarboxylic or picolinic acid) are added to the reaction mixture. Alkyl hydroperoxides are formed as main reaction products. The turnover numbers attain 140 for cyclohexane, 21 for ethane and four for methane oxidation. The oxidation proceeds non-stereoselectively and bond selectivity parameters are low which testifies the participation of hydroxyl radicals in alkane functionalization. (C) 2002 Elsevier Science Ltd. All rights reserved.
  • Publication
    Métadonnées seulement
    Oxidations by the reagent ?O 2?H 2 O 2?vanadium derivative?pyrazine-2-carboxylic acid?. Part 12. Main features, kinetics and mechanism of alkane hydroperoxidation
    (2001)
    Shul'pin, Georgiy B
    ;
    Kozlov, Yuriy N
    ;
    Nizova, Galina V
    ;
    Süss-Fink, Georg 
    ;
    Stanislas, Sandrine
    ;
    Kitaygorodskiy, Alex
    ;
    Kulikova, Vera S
  • Publication
    Métadonnées seulement
    Catalytic functionalization of methane
    (: John Wiley & Sons Ltd, 1999)
    Süss-Fink, Georg 
    ;
    Stanislas, Sandrine
    ;
    Shul'pin, Georgiy B
    ;
    Nizova, Galina V
    A mixture of sodium vanadate and pyrazine-2-carboxylic acid (pcaH) efficiently catalyses the reaction of methane with molecular oxygen (from air) and hydrogen peroxide to give methyl hydroperoxide and, as consecutive products, methanol and formaldehyde, The reaction takes place under mild conditions (25-75 degrees C) either in aqueous or in acetonitrile solution. The complexes formed from the catalyst precursor and the co-catalyst (under the reaction conditions) have been isolated and characterized as the derivatives [VO2(pca)(2)](-) (1) and [VO(O-2) (pca)(2)](-) (3). The implications of these species in the catalytic process are discussed. Copyright (C) 2000 John Wiley & Sons, Ltd.
  • Publication
    Métadonnées seulement
    Oxidations by the reagent 'O-2-H2O2 vanadate anion pyrazine-2-carboxylic acid'. Part 10 - Oxygenation of methane in acetonitrile and water
    (1998)
    Süss-Fink, Georg 
    ;
    Nizova, Galina V
    ;
    Stanislas, Sandrine
    ;
    Shul'pin, Georgiy B
    The oxidation of methane by a combination of air and hydrogen peroxide is effectively catalyzed in solution by a system composed of vanadate and pyrazine-2-carboxylic acid (PCA). In acetonitrile solution, containing the vanadate anion as tetrabutylammonium salt, the reaction gives, over a temperature range of 25 to 50 degrees C, methanol, carbon monoxide, formaldehyde, formic acid and carbon dioxide, the latter three compounds, however, being partially due to the oxidation of the acetonitrile used as the solvent, especially at higher temperatures. In aqueous solution, containing the vanadate anion in the form of the sodium salt, the reaction affords, over a temperature range of 40 to 70 degrees C, selectively methyl hydroperoxide within 4 h. The yield of CH3OOH attains 24%, based on H2O2, after 24 h at 50 degrees C, the catalytic turnover number being 480. The process seems to involve hydroxyl radicals, generated by the catalyst from H2O2 even at low temperatures. At 120 degrees C, methane is oxidized by O-2 and H2O2 to give formaldehyde and formic acid, even in the absence of the catalyst, presumably due to the formation of HO radicals from H2O2 in the presence of very low concentrations of metal ions from the autoclave under high temperature conditions. (C) 1998 Elsevier Science B.V.
  • Publication
    Accès libre
    Carboxylation of methane with CO or CO2 in aqueous solution catalysed by vanadium complexes
    (1998)
    Nizova, Galina V
    ;
    Süss-Fink, Georg 
    ;
    Stanislas, Sandrine
    ;
    Shul'pin, Georgiy B
    Reaction of methane with CO or CO2 in aqueous solution in the presence of O-2 (catalysed by NaVO3) or H2O2 (catalysed by NaVO3-pyrazine-2-carboxylic acid) at 25-100 degrees C affords acetic acid and in some cases also methanol, methyl hydroperoxide and formaldehyde.
  • Publication
    Métadonnées seulement
  • Publication
    Métadonnées seulement
    Oxygenation of methane with atmospheric oxygen in aqueous solution promoted by H2O2 and catalyzed by a vanadate ion-pyrazine-2-carboxylic acid system
    (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.