Oxidative cyclizations. II. Kinetic studies of the reaction of 2-nitroaniline with phenyliodoso acetate in toluene solution

1968 ◽  
Vol 21 (2) ◽  
pp. 409 ◽  
Author(s):  
LK Dyall ◽  
JOM Evans ◽  
JE Kemp
Keyword(s):  
Acetic Acid ◽  
Kinetic Study ◽  
Oxidation Rate ◽  
Kinetic Studies ◽  
Toluene Solution ◽  
Mass Action ◽  
Action Effect ◽  
First Order ◽  
Oxidative Cyclizations ◽  
Two Stages

A kinetic study of the oxidation of 2-nitroaniline by phenyliodoso acetate in toluene solution reveals that the reaction is first order in both amine and oxidant. The mass action effects of products on oxidation rate demonstrate that at least two stages are involved in the reaction, and that the mass action effect of acetic acid is exerted only by its monomer. Evidence is obtained for the formation of an intermediate containing trivalent iodine. All these facts are consistent with the mechanism previously proposed by us for this reaction.

Oxidative cyclizations. III. Kinetic studies of the oxidation of 2,4-dinitroaniline and 2-benzoylaniline with (diacetoxyiodo)benzene

1973 ◽  
Vol 26 (9) ◽  
pp. 1969 ◽  
Author(s):  
LK Dyall ◽  
JE Kemp
Keyword(s):  
Acetic Acid ◽  
Equilibrium Constants ◽  
Kinetic Studies ◽  
Reaction Rates ◽  
Oxidative Cyclization ◽  
Toluene Solution ◽  
Common Mechanism ◽  
Substituted Anilines ◽  
Oxidative Cyclizations ◽  
Cyclic Product

For the oxidative cyclization of 2,4-dinitroaniline and 2- benzoylaniline with (diacetoxyiodo)benzene in toluene solution, the kinetic orders are unity in amine and oxidant, zero in iodobenzene and cyclic product, and -1 in monomeric acetic acid. These characteristic orders are also those observed for 2-nitroaniline and, together with evidence for a specific solvation effect by acetic acid on the reaction rates of all three amines, indicate that a common mechanism of oxidative cyclization applies to a range of ortho-substituted anilines. For 2-benzoylaniline, there is infrared evidence of an N-H bond in an iodoso intermediate. ��� Equilibrium constants for the monomer ↔ dimer equilibrium of acetic acid in toluene solution have been determined at four temperatures between 25� and 46�.

Kinetic Study of the Epimerization of 1,1,1-Trichloro-2-hydroxy-3-methyl-4-hexanone

1973 ◽  
Vol 51 (19) ◽  
pp. 3182-3186 ◽  
Author(s):  
Eberhard Kiehlmann ◽  
Fred Masaro ◽  
Frederick J. Slawson
Keyword(s):  
Activation Energy ◽  
Acetic Acid ◽  
Kinetic Study ◽  
Glacial Acetic Acid ◽  
Initial Reaction ◽  
First Order ◽  
Kinetically Controlled ◽  
Different Temperatures ◽  
Pseudo First Order

The acetate-catalyzed epimerization of 1,1,1-trichloro-2-hydroxy-3-methyl-4-hexanone has been studied in glacial acetic acid as solvent at five different temperatures. The reaction follows pseudo first-order, reversible kinetics and is associated with an activation energy of 24.0 ± 0.4 kcal/mol. Rate and product studies have shown that epimerization occurs by an enolization–ketonization pathway rather than dehydration–rehydration or retroaldol–aldolization. The ratio of diastereomeric ketols formed by condensation of 2-pentanone and 2-heptanone with chloral does not change as a function of time while the stereochemistry of the chloral addition to cyclohexanone is kinetically controlled during the initial reaction period.

Degradation Kinetic of Oxytetracycline Antibiotic inside UV Reactor in the Presence of H2O2

2014 ◽  
Vol 625 ◽  
pp. 901-906
Author(s):  
Anisa Ur Rahmah ◽  
Sabtanti Harimurti ◽  
Abdul Aziz Omar ◽  
Thanabalan Murugesan
Keyword(s):  
Experimental Data ◽  
Kinetic Study ◽  
Regression Coefficient ◽  
Kinetic Studies ◽  
Second Order ◽  
Degradation Kinetic ◽  
First Order ◽  
Uv Reactor ◽  
Pseudo First Order ◽  
Veterinary Antibiotic

–Oxytetracycline (OTC), a widely used of veterinary antibiotic, was degraded inside a UV/H2O2system. Kinetic study was conducted at 30°C of temperature and pH 6.37, as suggested by the previous optimization experiment. About 250, 375 and 500 ppm initial OTC concentration were used for the kinetic studies, at H2O2concentration of 0.116 M. The experimental data were plotted against the pseudo zero-th, first and second order of kinetic. Based on regression coefficient value, the data was well fitted with the pseudo first order of kinetic. The calculated value ofkobswas 0.181 min-1.

Kinetic Study of Light Mercaptans in the Presence of Merox Catalyst and Caustic Soda

2013 ◽  
Vol 11 (1) ◽  
pp. 431-442 ◽  
Author(s):  
Mohammad Reza Ehsani ◽  
Peyman Mirjani ◽  
Alireza Safadoost
Keyword(s):  
Caustic Soda ◽  
Kinetic Study ◽  
Oxidation Rate ◽  
Order Reaction ◽  
First Order Reaction ◽  
Kinetic Investigation ◽  
First Order ◽  
Oxidation Rates

Abstract Due to the disgusting smell of light mercaptans, researchers are not interested in working with them, so there is not enough information available on their kinetics. This work presents kinetic investigation of oxidation of ethyl, normal-propyl, iso-propyl, and iso-butyl mercaptans in the presence of Merox catalyst. The results demonstrated that the oxidation rates of all mercaptans were first-order reaction with respect to mercaptan concentration, and the increase in NaOH concentration reduced the oxidation rate. While it was observed that there was a similarity between oxidation pattern of iso-propyl and ethyl mercaptans, another similarity was discovered between normal-propyl and iso-butyl mercaptans.

PHOTO-INITIATED REACTIONS OF THIOLS AND OLEFINS: I. THE THIYL RADICAL CATALYZED ISOMERIZATION OF BUTENE-2 AND 1,2-ETHYLENE-d2

1964 ◽  
Vol 42 (10) ◽  
pp. 2239-2249 ◽  
Author(s):  
D. M. Graham ◽  
R. L. Mieville ◽  
C. Sivertz
Keyword(s):  
Activation Energy ◽  
Thermal Decomposition ◽  
Kinetic Study ◽  
Rate Constants ◽  
Reaction Rate ◽  
Kinetic Studies ◽  
Thiyl Radical ◽  
First Order ◽  
Thiyl Radicals ◽  
Simple Mechanism

Kinetic studies have been made of the isomerization of butene-2 and 1,2-ethylene-d2 catalyzed by thiyl radicals produced from the photolysis of methanethiol. The rate of isomerization was found to be first order with respect to both the olefin and [Formula: see text] concentrations. The lack of influence of pressure on the reaction rate, at pressures above about 4 mm, leads to a simple mechanism in which isomerization is considered to occur as a result of thermal decomposition of the collisionally stabilized adduct radical produced in the reaction [Formula: see text]. The rate constants for this attack step were found to be 2 × 107 and 4.8 × 106 l mole−1 s−1 for butene-2 and ethylene-d2, respectively. In both cases the activation energy for isomerization was found to be close to zero. From a kinetic study of the isomerization of cis-butene-2 in the presence of butadiene-1,3, which acts as a retarder, the attack constant for butadiene at 25 °C was found to be 4.5 × 108 l mole−1 s−1.

Evaluation of Kinetic Parameters at the Transport of Indole-3-acetic Acid Through Bulk Liquid Membranes

2017 ◽  
Vol 68 (5) ◽  
pp. 903-907
Author(s):  
Ecaterina Anca Serban ◽  
Ioana Diaconu ◽  
Elena Ruse ◽  
Georgiana Ileana Badea ◽  
Adriana Cuciureanu ◽  
...  
Keyword(s):  
Acetic Acid ◽  
Kinetic Parameters ◽  
Trioctylphosphine Oxide ◽  
Bulk Liquid ◽  
Transport Parameters ◽  
Kinetics Parameters ◽  
First Order ◽  
Phase Concentration ◽  
Feed Phase ◽  
Indole 3 Acetic Acid

Indole-3-acetic acid is a growth phytohormone considered the most important representative of auxin class. This paper presents the assessment of some kinetic parameters in the process of transport of indole-3-acetic acid taking into consideration the kinetic model of consecutive irreversible first order reactions. It was pursued the influence upon the process of parameters such as: feed phase concentration, stripping phase concentration in the presence of two type carriers: tributyl phosphate (TBP) and trioctylphosphine oxide (TOPO). Depending on these transport parameters were calculated kinetics parameters such as: pseudo-first-order apparent membrane entrance and exit rate constants, the maximum flux at the entrance and exit out of the membrane. The highest values of the transport flux is obtained in the presence of carrier trioctylphosphine oxide (TOPO) at the concentration in the feed phase of 10-4 mol/L indole-3-acetic acid and a concentration of 10--2mol/L NaOH in the stripping phase.

Kinetic Studies of [4n+2]π-Thermal Cyclodimerization of 1-(3-Pyridazinyl)-3-oxidopyridinium Betaines

1992 ◽  
Vol 57 (9) ◽  
pp. 1951-1959 ◽  
Author(s):  
Madlene L. Iskander ◽  
Samia A. El-Abbady ◽  
Alyaa A. Shalaby ◽  
Ahmed H. Moustafa
Keyword(s):  
Energy Gap ◽  
Activation Parameters ◽  
Kinetic Studies ◽  
Cyclic Transition ◽  
Concerted Mechanism ◽  
First Order ◽  
Thermodynamic Activation Parameters ◽  
Cyclic Transition State ◽  
Complete Dissociation ◽  
Homo Lumo

The reactivity of the base induced cyclodimerization of 1-(6-arylpyridazin-3-yl)-3-oxidopyridinium chlorides in a pericyclic process have been investigated kinetically at λ 380 nm. The reaction was found to be second order with respect to the liberated betaine and zero order with respect to the base. On the other hand dedimerization (monomer formation) was found to be first order. It was shown that dimerization is favoured at low temperature, whereas dedimerization process is favoured at relatively high temperature (ca 70 °C). Solvent effects on the reaction rate have been found to follow the order ethanol > chloroform ≈ 1,2-dichloroethane. Complete dissociation was accomplished only in 1,2-dichloroethane at ca 70 °C. The thermodynamic activation parameters have been calculated by a standard method. Thus, ∆G# has been found to be independent on substituents and solvents. The high negative values of ∆S# supports the cyclic transition state which is in favour with the concerted mechanism. MO calculations using SCF-PPP approximation method indicated low HOMO-LUMO energy gap of the investigated betaines.

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 Synthesis of Nano-Sized Protonic Acid Catalyst and Initial Kinetic Study of Esterification Reaction of Methanol with Acetic Acid

2014 ◽  
Vol 26 (16) ◽  
pp. 4988-4994
Author(s):  
Jianjun Zhu ◽  
Qiuqing Cui ◽  
Jiangping Peng ◽  
Li Li Zhang ◽  
Zhongqing Jiang ◽  
...  
Keyword(s):  
Acetic Acid ◽  
Kinetic Study ◽  
Acid Catalyst ◽  
Esterification Reaction ◽  
Protonic Acid

scholarly journals Kinetics of K release from soils of Brazilian coffee regions: effect of organic acids

2008 ◽  
Vol 32 (2) ◽  
pp. 533-540 ◽  
Author(s):  
Vladimir Antônio Silva ◽  
Giuliano Marchi ◽  
Luiz Roberto Guimarães Guilherme ◽  
José Maria de Lima ◽  
Francisco Dias Nogueira ◽  
...  
Keyword(s):  
Release Kinetics ◽  
Kinetic Studies ◽  
Release Rates ◽  
First Order ◽  
Potassium Release ◽  
Minas Gerais State ◽  
Soil Clay ◽  
Extractant Solution ◽  
Kinetics Of ◽  
K Release

Kinetic studies on soil potassium release can contribute to a better understanding of K availability to plants. This study was conducted to evaluate K release rates from the whole soil, clay, silt, and sand fractions of B-horizon samples of a basalt-derived Oxisol and a sienite-derived Ultisol, both representative soils from coffee regions of Minas Gerais State, Brazil. Potassium was extracted from each fraction after eight different shaking time periods (0-665 h) with either 0.001 mol L-1 citrate or oxalate at a 1:10 solid:solution ratio. First-order, Elovich, zero-order, and parabolic diffusion equations were used to parameterize the time dependence of K release. For the Oxisol, the first-order equation fitted best to the experimental data of K release, with similar rates for all fractions and independent of the presence of citrate or oxalate in the extractant solution. For all studied Ultisol fractions, in which K release rates increased when extractions were performed with citrate solution, the Elovich model described K release kinetics most adequately. The highest potassium release rate of the Ultisol silt fraction was probably due to the transference of "non-exchangeable" K to the extractant solution, whereas in the Oxisol exchangeable potassium represented the main K source in all studied fractions.

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