764-81-8Relevant articles and documents
Hydroperoxidation of methane and other alkanes with H2O2 catalyzed by a dinuclear iron complex and an amino acid
Nizova, Galina V.,Krebs, Bernt,Süss-Fink, Georg,Schindler, Siegfried,Westerheide, Lars,Gonzalez Cuervo, Laura,Shul'pin, Georgiy B.
, p. 9231 - 9237 (2007/10/03)
The compound [Fe2(HPTB)(μ-OH)(NO3)2](NO3) 2·CH3OH·2H2O (1) containing a dinuclear iron(III) complex in which HPTB=N,N,N′,N′-tetrakis(2-benzimidazolylmethyl)-2-hydroxo-1,3- diaminopropane 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.
Oxidations by the reagent "O2-H2O2-vanadium derivative-pyrazine-2-carboxylic acid". Part 12. Main features, kinetics and mechanism of alkane hydroperoxidation
Shul'pin, Georgiy B.,Kozlov, Yuriy N.,Nizova, Galina V.,Suess-Fink, Georg,Stanislas, Sandrine,Kitaygorodskiy, Alex,Kulikova, Vera S.
, p. 1351 - 1371 (2007/10/03)
Various combinations of vanadium derivatives (n-Bu4NVO3 is the best catalyst) with pyrazine-2-carboxylic acid (PCA) catalyse the oxidation of saturated hydrocarbons, RH, with hydrogen peroxide and air in acetonitrile solution to produce, at temperatures V(PCA)(H2O2) → VIV(PCA) + HOO. + H+. The VIV species thus formed reacts further with a second H2O2 molecule to generate the hydroxyl radical according to the equation VIV(PCA) + H2O2 → VV(PCA) + HO. + HO-. The concentration of the active species in the course of the catalytic process has been estimated to be as low as [V(PCA)H2O2] ≈ 3.3 × 10-6 mol dm-3. The effective rate constant for the cyclohexane oxidation (d[ROOH]/dt = keff[H2O2]0[V]0) is keff = 0.44 dm3 mol-1 s-1 at 40 °C, the effective activation energy is 17 ± 2 kcal mol-1. It is assumed that the accelerating role of PCA is due to its facilitating the proton transfer between the oxo and hydroxy ligands of the vanadium complex on the one hand and molecules of hydrogen peroxide and water on the other hand. For example: (pca)(O=)V ... H2O2 → (pca)(HO-)V-OOH. Such a "robot's arm mechanism" has analogies in enzyme catalysis.
Oxidations by the reagent O2-H2O2-vanadium complex - Pyrazine-2-carboxylic acid. Part 7. Hydroperoxidation of higher alkanes
Shul'pin, Georgiy B.,Guerreiro, Mario C.,Schuchardt, Ulf
, p. 13051 - 13062 (2007/10/03)
Alkanes (n-heptane, 2- and 3-methylhexane, cis- and trans-decalin) are readily oxidized under air in acetonitrile by the O2-H2O2-PCA-VO3- reagent at room temperature to produce alkyl hydroperoxides as main products as well as minor amounts of the corresponding alcohols and carbonyl compounds. The site selectivities of the reactions are very similar to those observed with hydroxylation of the alkanes with hydrogen peroxide under UV irradiation. The proposed mechanism involves the catalytic formation of hydroxyl radicals from hydrogen peroxide which abstract hydrogen atoms from the alkanes. The alkyl radicals react rapidly with molecular oxygen to produce peroxyl radicals which are transformed mainly into the hydroperoxides.
