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Desai, S. M.; Halligudi, Nirmala; Nandibewoor, Sharanappa T.

doi:10.1023/a:1013952005346

Cited by 27 publications

(11 citation statements)

References 16 publications

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“…Ruthenium(III) catalysis in redox reactions involves different degrees of complexity, due to the formation of different intermediate complexes, free radicals and to different oxidation states of ruthenium. Bromate oxidations of organic and inorganic reactions usually involve complications such as an induction period [11], autocatalysis [12] and involvement of two reactions [13]. Even bromate oxidations sometimes involve oscillation reactions [14].…”

Section: Introductionmentioning

confidence: 99%

Aquachlororuthenium(III) complex catalysis in the oxidation of malonic and methylmalonic acids by bromate in perchloric acid medium. Study of induction period and evaluation of individual kinetic parameters

Reddy

Kumar

2007

Transition Met Chem

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The kinetics and mechanism of an aquachlororuthenium(III) complex catalyzed oxidation of malonic and methylmalonic acids by bromate in aqueous acetic acid medium containing perchloric acid and mercury(II) is reported here. The reaction shows an induction period (s 0 ), whose duration is inversely proportional to [substrate] 0 and [catalyst] 0 , and temperature; however, independent of [bromate] 0 . After induction, the reaction exhibits first order each in [bromate] and [catalyst], less than unit order in [substrate] and an inverse fractional order in [HClO 4 ]. The reaction also shows an inverse solvent isotope effect ( k D 2 O =k H 2 O ¼ 0:72 AE 0:05:) The observed rate law is interpreted by a mechanism involving the oxidation of Ru III to Ru V by Br V (K f ), followed by complex formation (K c ) between the Ru V and enol form (K en ) of the substrate in 1:1 ratio, which decomposes (kd) into products in the ratedetermining step with regeneration of Ru III . The observed induction period is interpreted as the time-lag in buildingup of the reactive intermediate(s). The reaction constants (K f , K c , K en and kd) involved in the mechanism proposed have been evaluated and s 0 has been correlated in terms of initial concentrations of substrate and catalyst as::

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Section: Introductionmentioning

confidence: 99%

Aquachlororuthenium(III) complex catalysis in the oxidation of malonic and methylmalonic acids by bromate in perchloric acid medium. Study of induction period and evaluation of individual kinetic parameters

Reddy

Kumar

2007

Transition Met Chem

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“…1). The k obs values were reproducible within ±5% and are the average of at least three independent kinetic runs (Table I) [14,15]. …”

Section: Methodsmentioning

confidence: 99%

Autocatalytic Oxidation of Thiamine Hydrochloride (Vitamin B₁ ) by Permanganate in Aqueous Sulfuric Acid Medium: A Kinetic and Mechanistic Study

Savanur

Teradale

Lamani

et al. 2016

Int. J. Chem. Kinet.

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The reaction kinetics of autocatalytic oxidation of thiamine hydrochloride (vitamin B 1 ) by the permanganate ion in aqueous sulfuric acid medium has been investigated spectrophotometrically under the pseudo-first-order condition at 25°C. The observed stoichiometry is 6:5 in terms of the mole ratio of permanganate ions and thiamine hydrochloride. Formation of products was confirmed by UV-vis, IR, GC-MS, and NMR spectral data. Usually in the permanganate oxidation-reduction reactions, one of the products, Mn 2+ autocatalyzes the reaction, but in the present investigation the autocatalytic effect is due to the (4-methyl-thiazol-5-yl) acetic acid, a product formed from the oxidation of vitamin B 1 , which is a rare case. The added Mn 2+ does not have any significant effect on the rate of reaction. The reaction is first order with respect to both permanganate and thiamine hydrochloride concentrations. An increase in the sulfuric acid concentration decreases the rate of reaction. A composite scheme and rate laws were proposed. The activation parameters with respect to the slow step and reaction constants involved in the mechanism were determined and discussed. C 2016 Wiley Periodicals, Inc. Int J Chem Kinet 48: 281

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“…Under experimental conditions, [2-propenol] T ) [Cr(VI)] T (T = total concentration), 2-propenol oxidized to 2-propenal (separated from mixture by fractional distillation), as confirmed by a 2,4-dinitrophenylhydrazine (DNP) test [19]. After completion of the reaction, the mixture solution was treated with an excess of a saturated solution of 2,4-DNP in dilute H 2 SO 4 medium.…”

Section: Product Analysis and Stoichiometrymentioning

confidence: 99%

“…Therefore, we can say that bipy in the presence of SDS is the best promoter for the oxidation of 2-propenol by Cr(VI). A table comparing our results (Table S3) explains the selection of suitable catalysts and promoters over the other oxidants used previously in 2-propenol to 2-popenal conversion [19][20][21]37].…”

Section: Reaction Mechanism and Rate Lawmentioning

confidence: 99%

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Sodium dodecylsulphate-catalyzed hetero-aromatic nitrogen base-promoted chromium(VI) oxidation of 2-propenol to 2-propenal in aqueous media

et al. 2015

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A kinetic study of homogeneously micelle-catalyzed, hetero-aromatic Nbase (2-picolinic acid, 2,2 0 -bipyridine and 1,10-phenanthroline)-promoted oxidation of 2-propenol by chromium(VI) in sulfuric acid medium was carried out at 303 K. The pseudo first-order rate constant (k obs ) of the oxidation reaction is directly proportional to [H ? ] and [promoters], which indicates that the reaction is first order with respect to H ? and promoters. The reaction was conducted at four different temperatures from which the activation parameters were calculated. Proton nuclear magnetic resonance ( 1 H-NMR) studies were performed to detect the location of reactant molecules in nanometersized micelles. From the observed kinetic results, a suitable mechanism consistent with the rate law has been proposed. The micelles produced a catalytic effect in the entire range of sodium dodecylsulphate (SDS) concentrations used, and the effect is explained by pseudo-phase ion exchange. The combination of 2,2 0 -bipyridine (bipy) and SDS exhibited a 15-fold rate enhancement of Cr(VI) oxidation of 2-propenol to 2-propenal. Electronic supplementary material The online version of this article (Graphical Abstract Ultraviolet-visible (UV-Vis) spectrum of reaction mixture for the Cr(VI) oxidation of 2-propenol with varying solution colour at different reaction times. Right: Location of reactant molecule in the micellar pseudophase region.

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Cited by 27 publications

References 16 publications

Aquachlororuthenium(III) complex catalysis in the oxidation of malonic and methylmalonic acids by bromate in perchloric acid medium. Study of induction period and evaluation of individual kinetic parameters

Aquachlororuthenium(III) complex catalysis in the oxidation of malonic and methylmalonic acids by bromate in perchloric acid medium. Study of induction period and evaluation of individual kinetic parameters

Autocatalytic Oxidation of Thiamine Hydrochloride (Vitamin B₁ ) by Permanganate in Aqueous Sulfuric Acid Medium: A Kinetic and Mechanistic Study

Sodium dodecylsulphate-catalyzed hetero-aromatic nitrogen base-promoted chromium(VI) oxidation of 2-propenol to 2-propenal in aqueous media

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Untitled

Cited by 27 publications

References 16 publications

Aquachlororuthenium(III) complex catalysis in the oxidation of malonic and methylmalonic acids by bromate in perchloric acid medium. Study of induction period and evaluation of individual kinetic parameters

Aquachlororuthenium(III) complex catalysis in the oxidation of malonic and methylmalonic acids by bromate in perchloric acid medium. Study of induction period and evaluation of individual kinetic parameters

Autocatalytic Oxidation of Thiamine Hydrochloride (Vitamin B1 ) by Permanganate in Aqueous Sulfuric Acid Medium: A Kinetic and Mechanistic Study

Sodium dodecylsulphate-catalyzed hetero-aromatic nitrogen base-promoted chromium(VI) oxidation of 2-propenol to 2-propenal in aqueous media

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Autocatalytic Oxidation of Thiamine Hydrochloride (Vitamin B₁ ) by Permanganate in Aqueous Sulfuric Acid Medium: A Kinetic and Mechanistic Study