scholarly journals Mechanistic Investigation of Oxidation of Phenylpropanolamine withN-Bromobenzenesulfonamide in Alkaline Medium: A Kinetic Approach

2008 ◽  
Vol 5 (2) ◽  
pp. 331-341
Author(s):  
Ningegowda Prasad ◽  
Kikkeri N. Mohana
Keyword(s):  
Alkaline Medium ◽  
Activation Parameters ◽  
Chloride Ion ◽  
Reaction Scheme ◽  
Kinetics Of Oxidation ◽  
Rate Law ◽  
Conjugate Acid ◽  
Mechanistic Investigation ◽  
Different Temperatures ◽  
Kinetics Of

The kinetics of oxidation of phenylpropanolamine (PPA) with sodium N-bromobenzenesulfonamide or bromamine-B (BAB) has been investigated in alkaline medium at 308 K. The oxidation reaction obeys the rate law, – d[BAB]/dt = k [BAB] [PPA]x [OH-], where x is less than unity. The variation of ionic strength of the medium, addition of the reduction product, benzenesulfonamide, and chloride ion had no pronounced effect on the reaction rate. Decrease of dielectric permittivity of the medium by increasing the CH3CN content increased the rate. The reaction was studied at different temperatures and the activation parameters have been evaluated from the Arrhenius plot. The stiochiometry of the reaction was found to be 1:1, and the oxidation product of phenylpropanolamine was identified as benzaldehyde and ethylideneamine. The rate decreased in D2O medium and the normal isotope effect k' (H2O) / k' (D2O) is 2.18. Proton inventory studies have been made in H2O - D2O mixtures. Formation and decomposition constant of BAB-PPA complexes in the reaction scheme have been determined. The conjugate acid, C6H5SO2NHBr is assumed to be the reactive species. The proposed mechanism and the derived rate law are consistent with the observed experimental results.

Kinetics and Mechanism of Oxidation of Thiocyanate Ion by Sodium N-Chloro-4-methyl Benzene Sulphonamide in Alkaline Medium

1979 ◽  
Vol 34 (1) ◽  
pp. 52-57 ◽  
Author(s):  
D. S. Mahadevappa ◽  
B. T. Gowda ◽  
N. M. M. Gowda
Keyword(s):  
Activation Parameters ◽  
Potassium Thiocyanate ◽  
Kinetics Of Oxidation ◽  
Rate Law ◽  
Thiocyanate Ion ◽  
Different Temperatures ◽  
Chloramine T ◽  
Solvent Isotope ◽  
Kinetics Of ◽  
Substrate Concentrations

Abstract Kinetics of oxidation of potassium thiocyanate by the oxidant chloramine-T (CAT) in presence of NaOH has been studied at 30 °C. At low substrate concentrations, the approximate rate law is, - d[CAT]/dt = k[CAT][KNCS]/[NaOH]2 . At higher substrate concentrations, the rate law simplifies to, -d[CAT]/dt = k[CAT]/[NaOH]. Ionic strength and addition of p-toluene sulphonamide have negligible influence on the rate. The rate of reaction decreases in D2O medium and the value of the inverse solvent isotope effect, kH2O/kD2O is 0.46. The reaction has been studied at different temperatures and the activation parameters have been calculated.

scholarly journals Kinetics of Oxidation of Amino Acids by a Newly Synthesized Oxidant, N-Chloropyrazinamide in Aqueous Acetic Acid Medium

2013 ◽  
Vol 16 ◽  
pp. 1-8
Author(s):  
S. Parimala Vaijayanthi ◽  
N. Mathiyalagan
Keyword(s):  
Amino Acids ◽  
Acetic Acid ◽  
Acid Medium ◽  
Activation Parameters ◽  
Aqueous Acetic Acid ◽  
Acetic Acid Medium ◽  
Kinetics Of Oxidation ◽  
Different Temperatures ◽  
Probable Reaction ◽  
Kinetics Of

The kinetics of oxidation of amino acids namely, alanine, glycine, leucine, phenyl alanine and valine by N-chloropyrazinamide (NCPZA) in aqueous acetic acid medium in the presence of hydrochloric acid have been investigated. The observed rate of oxidation is first order in [NCPZA], [H+] and [Clˉ]. The order with respect to [amino acid] is zero. The rate of oxidation increases with increase in the percentage of acetic acid. The reaction rate increases slightly with increase in ionic strength, while retards with addition of pyrazinamide. Arrhenius and thermodynamic activation parameters have been evaluated from Arrhenius plot by studying the reaction at different temperatures. A most probable reaction mechanism has been proposed and an appropriate rate law is deduced toaccount for the observed kinetic data.

scholarly journals Kinetics and Mechanism of Oxidation of Isoleucine byN-Bromophthalimide in Aqueous Perchloric Acid Medium

2011 ◽  
Vol 8 (4) ◽  
pp. 1728-1733 ◽  
Author(s):  
N. M. I. Alhaji ◽  
S. Sofiya Lawrence Mary
Keyword(s):  
Acid Medium ◽  
Perchloric Acid ◽  
Reaction Rate ◽  
Activation Parameters ◽  
Halide Ions ◽  
Kinetics Of Oxidation ◽  
First Order ◽  
Hypobromous Acid ◽  
Different Temperatures ◽  
Kinetics Of

The kinetics of oxidation of isoleucine withN-bromophthalimide has been studied in perchloric acid medium potentiometrically. The reaction is of first order each in [NBP] and [amino acid] and negative fractional order in [H+]. The rate is decreased by the addition of phthalimide. A decrease in the dielectric constant of the medium increases the rate. Addition of halide ions or acrylonitrile has no effect on the kinetics. Similarly, variation of ionic strength of the medium does not affect the reaction rate. The reaction rate has been determined at different temperatures and activation parameters have been calculated. A suitable mechanism involving hypobromous acid as reactive species has been proposed.

scholarly journals Mechanism of Oxidation of L-Histidine by Heptavalent Manganese in Alkaline Medium

2005 ◽  
Vol 2 (1) ◽  
pp. 75-85 ◽  
Author(s):  
Timy P. Jose ◽  
Sharanappa T. Nandibewoor ◽  
Suresh M. Tuwar
Keyword(s):  
Ionic Strength ◽  
Alkaline Medium ◽  
Reaction Medium ◽  
Activation Parameters ◽  
Slow Step ◽  
Thermodynamic Quantities ◽  
Kinetics Of Oxidation ◽  
Reaction Constants ◽  
Kinetics Of ◽  
Equilibrium Step

The kinetics of oxidation of L-histidine by manganese(VII) in aqueous alkaline medium at a constant ionic strength of 0.05 mol dm-3was studied spectrophotometrically. The reaction between permanganate and L-histidine in alkaline medium exhibits 2:1 stoichiometry (KMnO4: L-histidine). The reaction is of first order in [KMnO4], less than unit order in [L-histidine] and [alkali]. Decrease in the dielectric constant of the medium decreases the rate of reaction. Effect of added products and ionic strength of the reaction medium have been investigated. The main products were identified by spot test and I.R. A mechanism involving the free radical has been proposed. In composite equilibrium step L-histidine binds to MnO4-species to form a complex(C). The reaction constants involved in the different steps of mechanism are evaluated. The activation parameters with respect to slow step of the mechanism are computed and discussed and thermodynamic quantities are also determined.

scholarly journals Oxidation of Paracetamol Drug by a New Oxidant Diperiodatoargentate (III) in Aqueous Alkaline Medium

2006 ◽  
Vol 3 (1) ◽  
pp. 13-24 ◽  
Author(s):  
D. C. Hiremath ◽  
C. V. Hiremath ◽  
S. T. Nandibewoor
Keyword(s):  
Ionic Strength ◽  
Alkaline Medium ◽  
Reaction Medium ◽  
Activation Parameters ◽  
Slow Step ◽  
Thermodynamic Quantities ◽  
Kinetics Of Oxidation ◽  
Rate Determining Step ◽  
Reaction Constants ◽  
Kinetics Of

The kinetics of oxidation of anti-pyretic drug, paracetamol by diperiodatoargentate (III) (DPA) in alkaline medium at a constant ionic strength of 0.01 mol dm-3was studied spectrophotometrically. The reaction between DPA and paracetamol in alkaline medium exhibits 1:2 stoichiometry (paracetamol: DPA). The reaction is of first order in [DPA] and has less than unit order in both [PAM] and [alkali]. A decrease in the dielectric constant of the medium increases the rate of the reaction. The effect of added products and ionic strength of the reaction medium have been investigated. The oxidation reaction in alkaline medium has been shown to proceed via a DPA- paracetamol complex, which decomposes slowly in a rate determining step followed by other fast step to give the products. The main products were identified by spot test, IR, NMR and GC-MS. The reaction constants involved in the different steps of the mechanism are calculated. The activation parameters with respect to slow step of the mechanism are computed and discussed and thermodynamic quantities are also determined.

scholarly journals Kinetics and mechanism of the oxidation of polyhydric alcohols by dihydroxyditelluratoargentate(III) in alkaline medium

2005 ◽  
Vol 70 (4) ◽  
pp. 585-592 ◽  
Author(s):  
J.H. Shan ◽  
S.Y. Huo ◽  
S.G. Shen ◽  
H.W. Sun
Keyword(s):  
Alkaline Medium ◽  
Activation Parameters ◽  
Order Rate Constant ◽  
Active Species ◽  
Rate Equations ◽  
Kinetics Of Oxidation ◽  
First Order ◽  
Rate Determining Step ◽  
Plausible Mechanism ◽  
Kinetics Of

The kinetics of oxidation of 1,2-propanediol and 1,2,3-propanetriol by dihydroxyditelluratoargentate(III) (DDA) were studied spectrophotometrically between 298.2 K and 313.2 K in alkaline medium. The reaction rate showed first order dependence on DDA and 1 < nap < 2 order on the reductant. It was found that the pseudo-first order rate constant kobs increased with increasing concentration of OH-1 and decreasing concentration of TeO42-. There is a negative salt effect and no free radicals were detected. In view of this, the dihydroxymonotelluratoargentate(III) species is assumed to be the active species. A plausible mechanism involving a two-electron transfer is proposed and the rate equations derived from the mechanism can explain all the experimental results. The activation parameters, as well as the rate constants of the rate-determining step were calculated.

Kinetics and Mechanism of Oxidation of L-Proline by Heptavalent Manganese: A Free Radical Intervention and Decarboxylation

2005 ◽  
Vol 2005 (1) ◽  
pp. 13-17 ◽  
Author(s):  
R.T. Mahesh ◽  
M.B. Bellakki ◽  
S.T. Nandibewoor
Keyword(s):  
Reaction Rate ◽  
Activation Parameters ◽  
Solvent Polarity ◽  
Reaction Scheme ◽  
Slow Step ◽  
Reaction Products ◽  
Experimental Conditions ◽  
Kinetics Of Oxidation ◽  
Reaction Constants ◽  
Kinetics Of

The kinetics of oxidation of L-proline by permanganate in alkaline medium was studied spectrophotometrically. The reaction is first order with respect to[MnO4-] and is an apparent less than unit order, each in [L-proline] and [alkali] under the experimental conditions. The reaction rate increases with increase in ionic strength and decrease in solvent polarity of the medium. Addition of reaction products has no effect on the reaction rate. A mechanism involving the formation of a complex between the oxidant and substrate has been proposed. The reaction constants involved in the mechanism were evaluated. There is a good agreement between the observed and calculated rate constants under varying experimental conditions. The activation parameters with respect to the slow step of the proposed reaction scheme were evaluated and discussed.

Mechanistic Study of the Oxidation of Isonicotinate ion by Diperiodatocuprate(III) in Aqueous Alkaline Medium

2005 ◽  
Vol 2005 (3) ◽  
pp. 197-201 ◽  
Author(s):  
G.C Hiremath ◽  
R.M Mulla ◽  
S.T Nandibewoor
Keyword(s):  
Ionic Strength ◽  
Alkaline Medium ◽  
Activation Parameters ◽  
Mechanistic Study ◽  
Slow Step ◽  
Thermodynamic Quantities ◽  
Aqueous Alkaline Medium ◽  
Kinetics Of Oxidation ◽  
Reaction Constants ◽  
Kinetics Of

The kinetics of oxidation of isonicotinate ion by diperiodatocuprate(III) (DPC) in aqueous alkaline medium at a constant ionic strength of 0.60 mol dm−3 was studied spectrophotometrically. A mechanism involving the formation of an intermediate complex between the diperiodatocuprate(III) as the oxidant species and isonicotinate ion is proposed. The reaction constants involved in the different steps of mechanism have been calculated. The activation parameters with respect to the slow step of the mechanism have been computed and discussed and thermodynamic quantities were also determined.

Kinetics of Oxidation of Benzaldehydes by Quinolinium Dichromate

2003 ◽  
Vol 58 (12) ◽  
pp. 1201-1205 ◽  
Author(s):  
Hesham A. A. Medien
Keyword(s):  
Acetic Acid ◽  
Sulfuric Acid ◽  
Activation Parameters ◽  
Reaction Rates ◽  
Water Medium ◽  
Kinetics Of Oxidation ◽  
First Order ◽  
Different Temperatures ◽  
Acetic Acid Water ◽  
Kinetics Of

Quinolinium dichromate (QDC) in sulfuric acid oxidizes benzaldehydes to the corresponding acids in a 50% (v/v) acetic acid-water medium. The reaction is first order each in [QDC], [substrate] and [H+]. The reaction rates have been determined at different temperatures and the activation parameters calculated. The rate decreases with an increase in the water content of the medium. The effects of substituents have been studied. A suitable mechanism is proposed.

Kinetic and thermodynamic properties of pharmaceutical drug (Gabapentin) by potassium bromate (KBrO3) in presence of micro amount of Ir(III) chloride as catalyst in acidic medium

2019 ◽  
Author(s):  
Chem Int
Keyword(s):  
Thermodynamic Properties ◽  
Acidic Medium ◽  
Activation Parameters ◽  
Chloride Ion ◽  
Potassium Bromate ◽  
Pharmaceutical Drug ◽  
Rate Law ◽  
First Order ◽  
Rate Of Reaction ◽  
Different Temperatures

The kinetic and thermodynamic properties of pharmaceutical drug (gabapentine) by potassium bromate (KBrO3) in presence of Micro amount of Ir(III) chloride as catalyst in acidic medium was studied in the temperature range 30 to 45 0C. The reaction is carried out in the presence of mercuric acetate as a scavenger for chloride ion. 1-carboxy cyclohexane l-acetic acid was obtained as the oxidation product and identified chromatographically. The rate law followed a first order and zero order dependence with respect to KBrO3 and GBP respectively. The reaction followed first order with respect to Ir(III) chloride and [H+]. Negligible effect of [Hg(OAc)2] and ionic strength of the medium was observed. Chloride ion positively influenced the rate of reaction. The values of rate constants observed at different temperatures (30 to 45 0C) were utilized to calculate the activation parameters. Feasible mechanism is proposed which are composed with the kinetics, stochiometry and product of the reaction. The rate law has been derived from obtained kinetic data.

Sign in / Sign up

Export Citation Format

Share Document