Kinetic and thermodynamic study of Os(VIII) catalysed oxidation of glycine by ferrate(VI) in alkaline medium

2019 ◽  
Author(s):  
Chem Int
Keyword(s):  
Main Product ◽  
Activation Parameters ◽  
Basic Medium ◽  
First Order ◽  
Catalysed Oxidation ◽  
Rate Of Reaction ◽  
Different Temperatures ◽  
Experimental Findings ◽  
Kinetic And Thermodynamic Study ◽  
By Products

Kinetic and thermodynamic investigation on Os(VIII) catalysed oxidation of glycine by ferrate(VI) has been done in basic medium and in the temperature range 30– 450C. Rate of oxidation increases with increase in [FeO4]2- and [Os(VI)] and shows first order dependence. Rate of oxidation also increases with the increase in [S] but order is fractional. The rate decreases with an increase in pH. Rate of reaction is independent of [KCl], [KNO3] and change in ionic strength. The values of rate constant observed at four different temperatures were used to calculate the activation parameters. The energy of activation (ΔE*) of the reaction at pH 11 and temperature 350C was found to be 49.56 kJmol-1. [OsO4(H2O)2] and [FeO42−] are proposed to be the reactive species of Os(VIII) and Fe(VI) respectively in the present investigation. Formaldehyde is found to be main product of the reaction along with carbon dioxide and ammonia as by products. On the basis of experimental findings, a suitable mechanism consistent with the observed kinetics is proposed and a rate law has been derived on the basis of obtained data.

scholarly journals Kinetics and Mechanism of Oxidation of Malic Acid by N-Bromonicotinamide (NBN) in the Presence of a Micellar System

2015 ◽  
Vol 52 ◽  
pp. 111-119
Author(s):  
L. Pushpalatha
Keyword(s):  
Malic Acid ◽  
Reaction Rate ◽  
Activation Parameters ◽  
Zero Order ◽  
Micellar System ◽  
First Order ◽  
First Order Kinetics ◽  
Rate Of Reaction ◽  
Different Temperatures ◽  
Experimental Findings

The oxidation of malic acid by N-bromonicotinamide in the presence of micellar system is studied. First order kinetics with respect to NBN is observed. The kinetics results indicate that the first order kinetics in hydroxy acid at lower concentrations tends towards a zero order at its higher concentrations. Inverse fractional order in [H+] and [nicotinamide] are noted throughout its tenfold variation. Variation of [Hg (OAc)2] and ionic strength of the medium do not bring about any significant change in the rate of reaction. Rate of the reaction increases with a decrease in the percentage of acetic acid. Decrease in the rate constant was observed with the increase in [SDS]. The values of rate constants observed at four different temperatures were utilized to calculate the activation parameters. A suitable mechanism consistent with the experimental findings has been 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.

scholarly journals Kinetics and Mechanism of Oxidation of Tartaric Acid by N-Chloronicotinamide (NCN)

2015 ◽  
Vol 52 ◽  
pp. 120-125 ◽  
Author(s):  
L. Pushpalatha
Keyword(s):  
Acetic Acid ◽  
Tartaric Acid ◽  
Fractional Order ◽  
Rate Constants ◽  
Activation Parameters ◽  
First Order ◽  
First Order Kinetics ◽  
Different Temperatures ◽  
Mechanism Of Oxidation ◽  
Experimental Findings

The oxidation of tartaric acid by N-chloronicotinamide in the presence of HClO4 is studied. First order kinetics with respect to NCN is observed. The kinetics results indicate fractional order dependence about [tartaric acid]. Inverse first order in [nicotinamide] and inverse fractional order about [H+] are noted. Rate of the reaction increases with a decrease in the percentage of acetic acid. The values of rate constants observed at four different temperatures were utilized to calculate the activation parameters. A suitable mechanism consistent with the experimental findings has been proposed.

scholarly journals Kinetics and Mechanism of the Change of the 4-Nitrobenzylthio-System into 4,4′-Diformylazoxybenzene in Alkaline Dioxane-Water Media

1985 ◽  
Vol 40 (11) ◽  
pp. 1128-1132
Author(s):  
Y. Riad ◽  
Adel N. Asaad ◽  
G.-A. S. Gohar ◽  
A. A. Abdallah
Keyword(s):  
Acetic Acid ◽  
Sodium Hydroxide ◽  
Rate Constants ◽  
Main Product ◽  
Reaction Medium ◽  
Aqueous Dioxane ◽  
Proton Abstraction ◽  
First Order ◽  
Water Media ◽  
Different Temperatures

Sodium hydroxide reacts with α -(4-nitrobenzylthio)-acetic acid in aqueous-dioxane media to give 4,4'-diformylazoxybenzene as the main product besides 4,4'-dicarboxyazoxybenzene and a nitrone acid. This reaction was kinetically studied in presence of excess of alkali in different dioxane-water media at different temperatures. It started by a fast reversible a-proton abstraction step followed by two consecutive irreversible first-order steps forming two intermediates (α -hydroxy, 4-nitrosobenzylthio)-acetic acid and 4-nitrosobenzaldehyde. The latter underwent a Cannizzaro's reaction, the products of which changed in the reaction medium into 4,4'-diformylazoxybenzene and 4,4'-dicarboxyazoxybenzene. The rate constants and the thermodynamic parameters of the two consecutive steps were calculated and discussed. A mechanism was put forward for the formation of the nitrone acid.Other six 4-nitrobenzyl, aryl sulphides were qualitatively studied and they gave mainly 4,4'-diformylazoxybenzene beside 4,4'-dicarboxyazoxybenzene or its corresponding azo acid.

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.

Kinetics of the Substitution of Norbornadiene in Tetracarbonyl(norbomadiene)molybdenum(0) by 2,2'-Bipyridine

2001 ◽  
Vol 56 (3) ◽  
pp. 281-286 ◽  
Author(s):  
Ceyhan Kayran ◽  
Eser Okan
Keyword(s):  
Reaction Rate ◽  
Activation Parameters ◽  
Bipy Ligand ◽  
First Order ◽  
Rate Determining Step ◽  
Vis Spectroscopy ◽  
Different Temperatures ◽  
Ft Ir ◽  
Thermal Substitution ◽  
Kinetics Of

Abstract The kinetics of the thermal substitution of norbornadiene (nbd) by 2,2'-bipyridine (2,2'-bipy) in (CO)4Mo(C7H9) was studied by quantitative FT-IR and UV-VIS spectroscopy. The reaction rate exhibits first-order dependence on the concentration of the starting complex, and the observed rate constant depends on the concentration of both leaving nbd and entering 2,2'-bipy ligand. The mechanism was found to be consistent with the previously proposed one, where the rate determining step is the cleavage of one of the two Mo-olefin bonds. The reaction was performed at four different temperatures (35 -50 °C) and the evaluation of the kinetic data gives the activation parameters which now support states.

scholarly journals Kinetics and mechanism of the oxidation of some cis-Alpha- Phenylcinnamic acids by Pyridinium Chlorochromate

2017 ◽  
Vol 12 (5) ◽  
pp. 4434-4441
Author(s):  
S. Nalini ◽  
R. Udhayakumar ◽  
K. Anbarasu ◽  
P. Manivannan ◽  
K. Raghu
Keyword(s):  
Reaction Rate ◽  
Activation Parameters ◽  
Sodium Chlorate ◽  
Dipole Interaction ◽  
Slow Step ◽  
Pyridinium Chlorochromate ◽  
Cinnamic Acids ◽  
Acetic Acid Medium ◽  
First Order ◽  
Rate Of Reaction

Oxidation of cis α-phenyl cinnamic acids by pyridinium chlorochromate (PCC) was studied in acetic acid–water mixturecontaining perchloric acid. The reaction rate is first order in [PCC] and fractional order in [H+] and has aldehyde as aproduct. The rate of reaction increases with increase in the percentage of acetic acid medium. The reactions exhibit kineticisotope effect. The activation parameters have been evaluated. The added Mn (II) decreases the rate of reaction. Theadded sodium chlorate has no effect on the reaction rate and indicates the absence of ion-ion (or) ion- dipole interaction inthe slow step. The deviation of Hammett plot is noted and a “V” shaped curve is obtained.

scholarly journals OXIDATION OF BENZALDEHYDE BY QUINOXALINIUM DICHROMATE

2016 ◽  
Vol 12 (9) ◽  
pp. 4396-4403 ◽  
Author(s):  
K Anbarasu ◽  
N. GEETHA
Keyword(s):  
Acetic Acid ◽  
Perchloric Acid ◽  
Reaction Rate ◽  
Sodium Perchlorate ◽  
Activation Parameters ◽  
Probable Mechanism ◽  
Water Medium ◽  
First Order ◽  
Rate Of Reaction ◽  
Acetic Acid Water

The kinetics and mechanism of oxidation of benzaldehyde by quinoxalinium dichromate has been studied in the presence of perchloric acid in 70 % acetic acid - water medium. The reaction follows first order with respect to benzaldehyde, quinoxalinium dichromate and fractional order with respect to perchloric acid. There is no effect on the reaction rate with increase in ionic strength of the medium by adding sodium perchlorate. The rate of reaction increases with increase in the percentage of acetic acid. The reaction does not induce the polymerization with acrylonitrile. The rate of reaction decreases with increase in the concentration of manganoussulphate. The thermodynamic and activation parameters have been calculated and a probable mechanism has been proposed.

Kinetics and mechanism of aminolysis of (Z)-4-arylidene-2-phenyl-5(4H)oxazolones

1992 ◽  
Vol 70 (10) ◽  
pp. 2515-2519 ◽  
Author(s):  
Sharifa S. Alkaabi ◽  
Ahmad S. Shawali
Keyword(s):  
Rate Constants ◽  
Activation Parameters ◽  
Order Conditions ◽  
Kinetics And Mechanism ◽  
Hammett Equation ◽  
Third Order ◽  
First Order ◽  
Different Temperatures ◽  
Pseudo First Order ◽  
Kinetics Of

The kinetics of the reactions of a series of (Z)-4-arylidene-2-phenyl-5(4H)oxazolones 1 with n-butylamine and piperidine were studied spectrophotometrically in dioxane, ethanol, and cyclohexane under pseudo-first-order conditions and at different temperatures. The relation k1(obs) = k2[amine] + k3[amine]2 was found applicable for all reactions studied in either dioxane or ethanol. However, in cyclohexane the n-butylaminolysis of 1 followed only third-order kinetics k1(obs) = k3[n-BuNH2]2. The kinetics of the reaction of 1 with n-butylamine in the presence of catalytic amounts of triethylamine in dioxane followed the equation: k1(obs)k2 = [n-BuNH2] + k3[n-BuNH2]2[Formula: see text] [Et3N]. The rate constants k2 and k3 correlated well with the Hammett equation and the corresponding activation parameters were determined. The results were interpreted in terms of a mechanism involving solvent- and amine-catalyzed processes.

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.

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