scholarly journals Solvation model for the oxidation of methionine by imidazolium fluorochromate in aqueous acetic acid medium

2006 ◽  
Vol 71 (1) ◽  
pp. 19-25 ◽  
Author(s):  
John Bincy ◽  
M. Pandeeswaran ◽  
D.S. Bhuvaneshwari ◽  
K.P. Elango
Keyword(s):  
Acetic Acid ◽  
Activation Parameters ◽  
Chloroacetic Acid ◽  
Reaction Rates ◽  
Aqueous Acetic Acid ◽  
Solvation Model ◽  
Acetic Acid Medium ◽  
Different Temperatures ◽  
Solute Interactions ◽  
Oxidation Of Methionine

The oxidation of methionine by imidazolium fluorochromate (IFC) were studied, in the presence of chloroacetic acid, in water-acetic acid mixtures of varying molar compositions. The reaction is first order with respect to methionine, IFC and acid. The reaction rates were determined at different temperatures and the activation parameters were computed. The reaction rate increases with increasing mole fraction of acetic acid in the mixture and specific solvent-solvent-solute interactions were found to predominate (86 %). A solvation model and a probable mechanism for the reaction are postulated.

scholarly journals Kinetics and mechanism of the oxidation of methionine by quinolinium chlorochromate

2005 ◽  
Vol 70 (2) ◽  
pp. 145-151 ◽  
Author(s):  
M. Pandeeswaran ◽  
John Bincy ◽  
D.S. Bhuvaneshwari ◽  
K.P. Elango
Keyword(s):  
Acetic Acid ◽  
Reaction Rate ◽  
Activation Parameters ◽  
Chloroacetic Acid ◽  
Reaction Rates ◽  
Solvation Model ◽  
First Order ◽  
Different Temperatures ◽  
Solute Interactions ◽  
Oxidation Of Methionine

The oxidation of methionine by quinolinium chlorochromate (QCC) has been studied, in the presence of chloroacetic acid, and in water-acetic acid mixtures of varying mole fractions. The reaction is first order with respect to methionine, QCC and acid. The reaction rates were determined at three different temperatures (25, 35 and 45 ?C) and the activation parameters were computed. The reaction rate increased with increasing mole fraction of acetic acid in the mixture and specific solvent-solvent-solute interactions were found to predominate (81 %). A solvation model and a suitable mechanism for the reaction are postulated.

scholarly journals Oxidation of Methionine by Tripropylammonium Fluorochromate-A Kinetic and Mechanistic Study

2011 ◽  
Vol 8 (2) ◽  
pp. 643-648 ◽  
Author(s):  
S. Sheik Mansoor
Keyword(s):  
Acetic Acid ◽  
Activation Parameters ◽  
Chloroacetic Acid ◽  
Mechanistic Study ◽  
Aqueous Acetic Acid ◽  
Acetic Acid Medium ◽  
Different Temperatures ◽  
Aqueous Mixture ◽  
Oxidation Of Methionine ◽  
Kinetics Of

The kinetics of oxidation of methionine (Met) by tripropylammonium fluorochromate (TriPAFC) has been studied in the presence of chloroacetic acid in aqueous acetic acid medium. The reaction is first order with respect to methionine, TriPAFC and acid. The reaction rate has been determined at different temperatures and activation parameters calculated. With an increase in the amount of acetic acid in its aqueous mixture, the rate increases. The reaction does not induce polymerization of acrylonitrile. A suitable mechanism has been proposed.

scholarly journals Kinetics and Mechanism of Oxidation of Aromatic Aldehydes by Imidazolium Dichromate in Aqueous Acetic Acid Medium

2009 ◽  
Vol 6 (s1) ◽  
pp. 522-528 ◽  
Author(s):  
S. Sheik Mansoor ◽  
S. Syed Shafi
Keyword(s):  
Acetic Acid ◽  
Acid Medium ◽  
Activation Parameters ◽  
Aromatic Aldehydes ◽  
Reaction Rates ◽  
Aqueous Acetic Acid ◽  
Acetic Acid Medium ◽  
Kinetics Of Oxidation ◽  
Different Temperatures ◽  
Kinetics Of

The kinetics of oxidation of benzaldehyde (BA) andpara-substituted benzaldehydes by imidazolium dichromate (IDC) has been studied in aqueous acetic acid medium in the presence of perchloric acid. The reaction is first order each in [IDC], [Substrate] and [H+]. The reaction rates have been determined at different temperatures and the activation parameters calculated. Electron withdrawing substituents are found to increase the reaction and electron releasing substituents are found to retard the rate of the reaction and the rate data obey the Hammett relationship. The products of the oxidation are the corresponding acids. The rate decreases with the increase in the water content of the medium. A suitable mechanism is proposed.

scholarly journals Perborate Oxidation of Substituted 5-Oxoacids in Aqueous Acetic Acid Medium: A Kinetic and Mechanistic Study

2014 ◽  
Vol 2014 ◽  
pp. 1-7 ◽  
Author(s):  
S. Shree Devi ◽  
B. Muthukumaran ◽  
P. Krishnamoorthy
Keyword(s):  
Acetic Acid ◽  
Acid Medium ◽  
Reaction Rate ◽  
Reaction Medium ◽  
Activation Parameters ◽  
Reaction Rates ◽  
Mechanistic Study ◽  
Aqueous Acetic Acid ◽  
Sodium Perborate ◽  
Acetic Acid Medium

Kinetics and mechanism of oxidation of substituted 5-oxoacids by sodium perborate in aqueous acetic acid medium have been studied. The reaction exhibits first order both in [perborate] and [5-oxoacid] and second order in [H+]. Variation in ionic strength has no effect on the reaction rate, while the reaction rates are enhanced on lowering the dielectric constant of the reaction medium. Electron releasing substituents in the aromatic ring accelerate the reaction rate and electron withdrawing substituents retard the reaction. The order of reactivity among the studied 5-oxoacids is p-methoxy ≫ p-methyl > p-phenyl > –H > p-chloro > p-bromo > m-nitro. The oxidation is faster than H2O2 oxidation. The formation of H2BO3+ is the reactive species of perborate in the acid medium. Activation parameters have been evaluated using Arrhenius and Eyring’s plots. A mechanism consistent with the observed kinetic data has been proposed and discussed. Based on the mechanism a suitable rate law is derived.

scholarly journals Reactivity of Phenol and Aniline towards Quinolinium Chloro Chromate: A Comparative Oxidation Kinetic Study

2015 ◽  
Vol 59 ◽  
pp. 81-92
Author(s):  
Seplapatty Kalimuthu Periyasamy ◽  
H. Satham Hussain ◽  
R. Manikandan
Keyword(s):  
Oxidation Kinetic ◽  
Activation Parameters ◽  
Dipole Interaction ◽  
Reaction Rates ◽  
Hydrogen Ion ◽  
Aqueous Acetic Acid ◽  
Acetic Acid Medium ◽  
First Order ◽  
Different Temperatures ◽  
Kinetics Of

The kinetics of Oxidation of Phenol and aniline by quinolinium Chlorochromate (QCC) in aqueous acetic acid medium leads to the formation of quinone and azobenzene respectively. The reactions are first order with respect to both Phenol and aniline. The reaction is first order with respect to quinolinium chlorochromate (QCC) and is catalyzed by hydrogen ion. The hydrogen-ion dependence has the form: kobs = a+b [H+]. The rate of oxidation decreases with increasing dielectric constant of solvent, indicating the presence of an ion-dipole interaction. The reaction does not induced the polymerization of acrylonitrile. The retardation of the rate by the addition of Mn2+ ions confirms that a two electron transfer process is involved in the reaction. The reaction rates have been determined at different temperatures and the activation parameters have been calculated. From the above observations kinetic results a probable mechanism have been proposed.

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 Effect of excess free energy of solvents on the oxidation of methionine by quinolinium fluorochromate: A kinetic study

2008 ◽  
Vol 73 (7) ◽  
pp. 735-744 ◽  
Author(s):  
D.S. Bhuvaneshwari ◽  
K.P. Elango
Keyword(s):  
Free Energy ◽  
Excess Free Energy ◽  
Activation Parameters ◽  
Chloroacetic Acid ◽  
Reaction Rates ◽  
Solvent Mixtures ◽  
Free Energy Function ◽  
Different Temperatures ◽  
Oxidation Of Methionine ◽  
Quinolinium Fluorochromate

The oxidation of methionine by quinolinium fluorochromate (QFC) was studied in the presence of chloroacetic acid, in water/organic solvent mixtures of varying excess molar free energy function. The reaction is first order with respect to both QFC and acid. The reaction rates were determined at different temperatures and the activation parameters computed. The rate data was correlated with different solvent parameters using linear multiple regression analysis. From the results, information on the solvent-reactants and the solvent-transition state interactions was obtained. .

scholarly journals Reactivity of Benzyl Alcohol and Substituted Benzyl Alcohols with 1-Chlorobenzimidazole in Acid Medium – A Kinetic and Mechanistic Approach

2016 ◽  
Vol 3 (3) ◽  
Author(s):  
M. Rukmangathan ◽  
V. Santhosh Kumar ◽  
B. Ramkumar
Keyword(s):  
Acetic Acid ◽  
Benzyl Alcohol ◽  
Acid Medium ◽  
Reaction Rates ◽  
Effect Of Temperature ◽  
Aqueous Acetic Acid ◽  
Product Analysis ◽  
Acetic Acid Medium ◽  
Benzyl Alcohols ◽  
Different Temperatures

<div><p><em>The kinetics of oxidation of benzyl alcohol and a few substituted benzyl alcohols with 1-chlorobenzimidazole (CBI) were studied in aqueous acetic acid medium. The order of the reactions with respect to each oxidant and substrate was found to be unity. The added HClO<sub>4</sub> increases the rate and the order in [HClO<sub>4</sub>] was found to be fractional. The reactions were catalyzed by NaCl and a fractional order dependence was observed for [NaCl]. The ionic strength had negligible influence on the rate. Increase in the percentage of acetic acid increases the rate. Addition of benzimidazole, one of the products does not affect the rate. Effect of temperature on the reaction rates was studied at different temperatures and the various activation and thermodynamic parameters were computed. The Hammett plot shows an excellent correlation with negative ρ value (- 0.37) for benzyl alcohols. Product analysis shows the formation of aldehydes as major products of oxidation of benzyl alcohols. CBIH<sup>+</sup> has been postulated as the reactive oxidizing species. Suitable mechanism and the rate law in consistent with the experimental results have been proposed.</em></p></div>

scholarly journals Meso-tetraphenylporphyriniron(iii) chloride catalyzed oxidation of aniline and its substituents by magnesium monoperoxyphthalate in aqueous acetic acid medium

2012 ◽  
Vol 14 (4) ◽  
pp. 35-41 ◽  
Author(s):  
Raja Manickam ◽  
Karunakaran Kulandaivelu
Keyword(s):  
Acetic Acid ◽  
Acid Medium ◽  
First Generation ◽  
Activation Parameters ◽  
Aqueous Acetic Acid ◽  
Substituted Anilines ◽  
Isokinetic Relationship ◽  
Acetic Acid Medium ◽  
Linear Free Energy ◽  
Energy Relationships

Abstract The catalytic properties of the first generation catalyst meso-tetraphenylporphyriniron(III) chloride and magnesium monoperoxyphthalate (MMPP) as oxidant have been studied in the oxidation of aniline and its substituents in acetic acid medium. The thermodynamic parameters for the oxidation have been determined and discussed. It confirms the Exner relationship (only at the low range of temperatures) and also some of the activation parameters to the isokinetic relationships. The magnesium monoperoxyphthalate oxidation with 18 ortho- meta- and para-substituted anilines fulfills with isokinetic relationship but not to any of the linear free energy relationships. The reaction mechanism and the rate law were proposed.

scholarly journals Kinetics of Oxidation of Some Amino Acids by N-Chlorosaccharin in Aqueous Acetic Acid Medium

2004 ◽  
Vol 1 (2) ◽  
pp. 127-131 ◽  
Author(s):  
N. A. Mohamed Farook ◽  
R. Prabaharan ◽  
S. Rahini ◽  
R. Senthil Kumar ◽  
G. Rajamahendran ◽  
...  
Keyword(s):  
Amino Acids ◽  
Acetic Acid ◽  
Acid Medium ◽  
Hypochlorous Acid ◽  
Activation Parameters ◽  
Slow Step ◽  
Aqueous Acetic Acid ◽  
Acetic Acid Medium ◽  
Kinetics Of Oxidation ◽  
Kinetics Of

The kinetics of oxidation of some amino acids namely, glycine, alanine, aspartic acid, arginine, and histidine, (AA) byN-chlorosaccharin (NCSA) in aqueous acetic acid medium in the presence of perchloric acid have been investigated. The observed rate of oxidation is first order in [AA], [NCSA] and of inverse fractional order in [H+]. The main product of the oxidation is the corresponding aldehyde. The ionic strength on the reaction rate has no significant effect. The effect of changing the dielectric constant of the medium on the rate indicates the reaction to be of dipole-dipole type. Hypochlorous acid has been postulated as the reactive oxidizing species. The reaction constants involved in the mechanism are derived. The activation parameters are computed with respect to slow step of the mechanism.

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