Kinetics and mechanism of the oxidation of some substituted aldonitrones by quinolinium chlorochromate in aqueous DMF medium in the absence and presence of oxalic acid

The kinetics of the oxidation of aldonitrones (nitrone) by quinolinium chlorochromate (QCC) was determined in 50 % DMF-water in the absence and presence of oxalic acid in order to study the effect of oxalic acid. It was considered worthwhile to investigate whether it undergoes co-oxidation or just functions as a catalyst in the reaction. The reaction was followed iodometrically. Under the employed experimental conditions, the reaction is first order each with respect to concentration of nitrone, QCC, and oxalic acid and fractional order with respect to H+ concentration. There was no discernible effect with increasing in ionic strength but the rate of oxidation decreased with decreasing dielectric constant of the medium. Addition of MnSO4 had a significant and acrylonitrile no effect on the reaction rate. A mechanism involving protonated nitrone and QCC as the reactive oxidant is proposed. The activation parameters were calculated and are presented.

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Kinetics of Oxidation of Benzoin by N. Bromosuccinimide

Mapana Journal of Sciences ◽

10.12723/mjs.6.11 ◽

2005 ◽

Vol 4 (1) ◽

pp. 55-61

Author(s):

R. Sridharan ◽

N. Mathiyalagan

Keyword(s):

Dielectric Constant ◽

Acetic Acid ◽

Reaction Rate ◽

Activation Parameters ◽

Aqueous Acetic Acid ◽

Kinetics Of Oxidation ◽

First Order ◽

First Order Kinetics ◽

Retarding Effect ◽

Kinetics Of

Kinetics of Oxidation of Benzoin by N. Bromosuccinimide[NBS] 80% aqueous acetic acid has been investigated. The reaction follows first-order kinetics with respect to both[NBS] and [benzoin]. The effect of varying ionic strength and dielectric constant indicate the reaction is dipole-dipole type. Addition of succinimide(>NH), has a retarding effect on the rate of oxidation. The product of oxidation is benzil. By studying the effect of temparature on the reaction rate, the Arrhenius and the activation parameters have been calculated. A suitable mechanism has been proposed and a rate low explaining the experiment results is derived.

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Kinetics and Mechanism of Hexachloroiridate(IV) Oxidation of Arsenic(III) in Acidic Perchlorate Solutions

Collection of Czechoslovak Chemical Communications ◽

10.1135/cccc19921451 ◽

1992 ◽

Vol 57 (7) ◽

pp. 1451-1458 ◽

Cited By ~ 6

Author(s):

Refat M. Hassan

Keyword(s):

Ionic Strength ◽

Fractional Order ◽

Activation Parameters ◽

Order Reaction ◽

First Order Reaction ◽

Intermediate Complex ◽

Constant Ionic Strength ◽

Kinetics Of Oxidation ◽

First Order ◽

Kinetics Of

The kinetics of oxidation of arsenic(III) by hexachloroiridate(IV) at lower acid concentrations and at constant ionic strength of 1.0 mol dm-3 have been investigated spectrophotometrically. A first-order reaction in [IrCl62-] and fractional order with respect to arsenic(III) have been observed. A kinetic evidence for the formation of an intermediate complex between the hydrolyzed arsenic(III) species and the oxidant was presented. The results showed that decreasing the [H+] is accompanied by an appreciable acceleration of the rate of oxidation. The activation parameters have been evaluated and a mechanism consistent with the kinetic results was suggested.

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

Zeitschrift für Naturforschung B ◽

10.1515/znb-2001-0310 ◽

2001 ◽

Vol 56 (3) ◽

pp. 281-286 ◽

Cited By ~ 5

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.

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Kinetics of oxidation of cis-bis(ethylenediamine)isothiocyanatonitrocobalt(III) ion with peroxodisulphate

Collection of Czechoslovak Chemical Communications ◽

10.1135/cccc19793588 ◽

1979 ◽

Vol 44 (12) ◽

pp. 3588-3594 ◽

Cited By ~ 4

Author(s):

Vladislav Holba ◽

Olga Volárová

Keyword(s):

Ionic Strength ◽

Rate Constants ◽

Oxidation Kinetics ◽

Reaction Rate ◽

Salt Effect ◽

Activation Parameters ◽

Reaction Products ◽

Kinetics Of Oxidation ◽

Thermodynamic Activation Parameters ◽

Kinetics Of

The oxidation kinetics of cis-bis(ethylenediamine)isothiocyanonitrocobalt(III) ion with peroxodisulphate was investigated in the medium of 0.01 M-HClO4 in dependence on the ionic strength and temperature and the reaction products were identified. Extrapolated values of thermodynamic activation parameters were determined from the temperature dependence of the rate constants extrapolated to zero ionic strength. The distance of the closest approach was estimated for the reacting ions by evaluating the primary salt effect. To elucidate the mechanism, the influence of the cyclic polyether 18-crown-6 on the reaction rate was followed.

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Kinetics and Mechanism of Oxidation of Glutamic Acid byN-Bromophthalimide in Aqueous Acidic Medium

E-Journal of Chemistry ◽

10.1155/2011/572603 ◽

2011 ◽

Vol 8 (4) ◽

pp. 1472-1477

Author(s):

N. M. I. Alhaji ◽

S. Sofiya Lawrence Mary

Keyword(s):

Dielectric Constant ◽

Ionic Strength ◽

Glutamic Acid ◽

Acidic Medium ◽

Reaction Medium ◽

Kinetics Of Oxidation ◽

First Order ◽

Mechanism Of Oxidation ◽

Kinetics Of ◽

Aqueous Acidic Medium

The kinetics of oxidation of glutamic acid (Glu) withN-bromophthalimide (NBP) was studied in perchloric acid medium at 30°C by potentiometric method. The reaction is first order each in NBP and glutamic acid and is negative fractional order in [H+]. Addition of KBr or the reaction product, phthalimide had no effect on the rate. Similarly variation of ionic strength of the medium did not affect the rate of the reaction. Also the rate increased with decrease in dielectric constant of the reaction medium. The thermodynamic parameters were computed from Arrhenius and Eyring plots. A suitable mechanism consistent with the kinetic results has been proposed.

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Oxidation of Some Aliphatic Alcohols by Pyridinium Chlorochromate -Kinetics and Mechanism

E-Journal of Chemistry ◽

10.1155/2009/907071 ◽

2009 ◽

Vol 6 (1) ◽

pp. 237-246 ◽

Cited By ~ 1

Author(s):

Sapana Jain ◽

B. L. Hiran ◽

C. V. Bhatt

Keyword(s):

Dielectric Constant ◽

Carbonyl Compounds ◽

Activation Parameters ◽

Dipole Interaction ◽

Hydrogen Ion ◽

Pyridinium Chlorochromate ◽

Secondary Alcohols ◽

Kinetics Of Oxidation ◽

First Order ◽

Kinetics Of

Kinetics of oxidation of some aliphatic primary and secondary alcoholsviz.,ethanol, propan-1-ol, propan-2-ol, butan-1-ol, butan-2-ol and 2-methyl butanol by pyridinium chlorochromate (PCC) have been studied in water- perchloric acid medium. The reaction shows first order dependence with respect to pyridinium chlorochromate [PCC] and hydrogen ion [H+]. The rate of oxidation decreases with increase in dielectric constant of solvent suggests ion-dipole interaction. Activation parameters have been evaluated. Products are carbonyl compounds and free radical absence was proved. A tentative mechanism has been proposed.

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

E-Journal of Chemistry ◽

10.1155/2011/917657 ◽

2011 ◽

Vol 8 (4) ◽

pp. 1728-1733 ◽

Cited By ~ 1

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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Cure Kinetics of an Optical Polythiourethane with Amine Catalyst by IR Analysis

International Journal of Polymer Science ◽

10.1155/2019/8194379 ◽

2019 ◽

Vol 2019 ◽

pp. 1-10

Author(s):

Weiping Du ◽

Guiming Zhang ◽

Song Wang ◽

Lianjiang Tan ◽

Huifang Chen

Keyword(s):

Reaction Rate ◽

Activation Parameters ◽

Cure Kinetics ◽

Order Kinetic ◽

Cure Reaction ◽

First Order ◽

Entropy Of Activation ◽

Catalyst Content ◽

Ir Analysis ◽

Kinetics Of

An optical polythiourethane based on m-xylylene diisocyanate (XDI) and 4-mercaptomethyl-3,6-dithia-1,8-octanedithiol (BES) has been studied. Triethylamine was adopted as a catalyst, and the solid-state isothermal cure reaction was carried out using FTIR spectroscopy, in the temperature range of 75°C-105°C. The -NCO absorption band of XDI was used to monitor the conversion of diisocyanate into polythiourethane. The reaction rate enhanced with an increase in the content of the catalyst, and the gel time determined by swelling test was shorter for the system with higher catalyst content. Kinetic parameters were calculated from the infrared spectrum data, and the results showed that the curing reaction of polythiourethane accords with first-order kinetic characteristics. The activation parameters obtained from the evaluation of kinetic data were △H∗=97.22 kJ mol−1, △S∗=−6.77 J K−1 mol−1, and Ea=100.23 kJ mol−1. The observed negative entropy of activation value supported the formation of a transition state in the cure reaction.

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Kinetics of periodate oxidation of polyoxyethylene – 300, a biodegradable pharmaceutical polymer

International Journal of Research in Pharmaceutical Sciences ◽

10.26452/ijrps.v10i4.1558 ◽

2019 ◽

Vol 10 (4) ◽

pp. 2830-2836

Author(s):

Koteswara Rao K.V.S ◽

Venkata Nadh R ◽

Venkata Ratnam K

Keyword(s):

Temperature Dependence ◽

Alkaline Medium ◽

Reaction Rate ◽

Periodate Oxidation ◽

Activation Parameters ◽

Aqueous Alkaline Medium ◽

Title Reaction ◽

First Order ◽

The Stability ◽

Kinetics Of

Polyoxyethylene Oxide – 300 (POE) is a well-known biodegradable pharmaceutical polymer. In order to understand the stability of POE and to derive the reaction rate law, the title reaction was carried out in aqueous alkaline medium, Reaction was found to be first order dependent on the concentration oxidant (periodate) and independent of substrate (POE) concentration. A retardation of reaction rate with an increase in hydroxide concentration shows an inverse fractional order in it. Based on the studies of the temperature dependence of reaction, evaluated the activation parameters.

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The mechanism of the oxidative deamination and decarboxylation of serine and threonine by periodate in acid medium

Canadian Journal of Chemistry ◽

10.1139/v85-389 ◽

1985 ◽

Vol 63 (9) ◽

pp. 2349-2353 ◽

Cited By ~ 7

Author(s):

Rosa Pascual ◽

Miguel A. Herráez

Keyword(s):

Amino Acid ◽

Acid Medium ◽

Rate Constants ◽

Reaction Rate ◽

Oxidative Deamination ◽

Experimental Conditions ◽

Kinetics Of Oxidation ◽

Rate Law ◽

First Order ◽

Kinetics Of

The kinetics of oxidation of serine and threonine by periodate have been investigated in acid medium at 10 °C. The reaction rate is first order in both periodate and amino acid, and the overall reaction follows second-order kinetics. The rates decrease with increase in [H+]. A catalytic effect of the buffers was not observed in the oxidation process. An analysis of the dependence of the rate on [H+] reveals that the reactive species under the experimental conditions are periodate monoanion and dianion and the dipolar form of the amino acid. The mechanism proposed and the derived rate law are consistent with the observed kinetics. The rate constants predicted using the derived rate law are in agreement with the observed rate constants, thus justifying this rate law and hence the proposed mechanistic scheme.

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