A kinetic study of the chlorination of ketones by chloramine-T: Novel concentration dependences on the chlorinating agent and the ketones

1976 ◽  
Vol 29 (7) ◽  
pp. 1449 ◽  
Author(s):  
V Balasubramanian ◽  
V Thiagarajan
Keyword(s):  
Acetic Acid ◽  
Kinetic Study ◽  
Acidic Medium ◽  
Aqueous Acetic Acid ◽  
Acetic Acid Medium ◽  
Rate Determining Step ◽  
Low Concentrations ◽  
Concentration Dependences ◽  
Chloramine T ◽  
High Concentrations

The chlorination of acetone in aqueous acidic medium in the presence of acetic acid and dimethylformamide was subjected to kinetic study. Although the kinetics follows the traditional mechanism at high concentrations of chloramine-T (cat) and in aqueous acetic acid in the presence of sodium acetate, a term in the rate law independent of ketone concentration is reported for the first time in strongly acidic medium at low concentrations of chloramine-T. Generation of the chlorinating species is considered as the rate-determining step (Scheme 1). The mechanistic changes which occur on addition of chloride and on changing the structure of the ketone are reported. The effect of acetate on the rate in aqueous acetic acid medium is rationalized by invoking a prior equilibrium formation of enolate followed by a rate-controlling chlorination by chlorinium acetate. The retardation in rate and the consequent changes in mechanism in the case of p-bromo- and p-nitroacetophenone are accounted for by invoking a complex between the enol and the positive chlorine species similar to that in the mechanism for the chlorination of phenols.

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 Kinetics and mechanism of meso-tetraphenylporphyriniron(III) chloride (TPP) catalysed oxidation of indole by sodium perborate

2013 ◽  
Vol 15 (2) ◽  
pp. 107-111 ◽  
Author(s):  
D. Kungumathilagam ◽  
K. Karunakaran
Keyword(s):  
Acetic Acid ◽  
Catalytic Activity ◽  
Reaction System ◽  
Kinetic Scheme ◽  
Mechanistic Study ◽  
Radical Mechanism ◽  
Aqueous Acetic Acid ◽  
Sodium Perborate ◽  
Acetic Acid Medium ◽  
Catalysed Oxidation

Developing catalyst is very significant for biologically important reactions which yield products, used as drugs. Mechanistic study on meso-tetraphenylporphyriniron(III) chloride (TPP) catalysed oxidation of indole by sodium perborate in aqueous acetic acid medium have been carried out. The reaction follows a fractional order with respect to substrate and catalyst. The order with respect to oxidant was found to be one. Increase in the percentage of acetic acid and increase in the concentration of [H+] decreased the rate. The reaction fails to initiate polymerization, and a radical mechanism is ruled out. Activation and thermodynamic parameters have been computed. A suitable kinetic scheme based on these observations has been proposed. Significant catalytic activity is observed for the reaction system in the presence of TPP.

scholarly journals Kinetics and mechanism of cetyltrimethylammonium bromide catalyzed oxidation of diethylene glycol by chloramine-T in acidic medium

2003 ◽  
Vol 68 (7) ◽  
pp. 535-542 ◽  
Author(s):  
V.W. Bhagwat ◽  
J. Tiwari ◽  
A. Choube ◽  
B. Pare
Keyword(s):  
Diethylene Glycol ◽  
Acidic Medium ◽  
Cetyltrimethylammonium Bromide ◽  
Reaction Rate ◽  
Chloride Ions ◽  
Kinetics And Mechanism ◽  
Product Analysis ◽  
Rate Determining Step ◽  
Chloramine T ◽  
Catalyzed Oxidation

The kinetics and mechanism of the C16TABcatalyzed oxidation of diethylene glycol (2,2?-oxydiethanol) by chloramine-T in acidic medium has been studied. The reaction has a first-order dependence on chloramine-T. With excess concentrations of other reactants, the reaction rate follows fractional order kinetics with respect to [diethylene glycol]. The micellar effect due to cetyltrimethylammonium bromide, a cationic surfactant, has been studied. The reaction is catalyzed by chloride ions as well. The small salt effect and increase in the reaction rate with increasing dielectric constant suggest the involvement of neutral molecules in the rate determining step. Addition of p-toluenesulfonamide retards the reaction rate. On the basis of product analysis, a pertinent mechanism is proposed.

Titrimetric Determination of Iodine-Bromine Numbers of Some Edible Oils Using Three N-Chloroimides

1987 ◽  
Vol 70 (4) ◽  
pp. 762-763
Author(s):  
Narayanan Jayasree ◽  
Parameswaran Indrasenan
Keyword(s):  
Acetic Acid ◽  
Reaction Time ◽  
Solid State ◽  
Palm Olein ◽  
Edible Oils ◽  
Aqueous Acetic Acid ◽  
Acetic Acid Medium ◽  
Back Titration ◽  
Titrimetric Determination

Abstract Three simple titrimetric methods have been developed to determine iodine-bromine numbers of some edible oils, such as coconut, gingelly, groundnut, mustard, olive, palm olein, and sunflower, using 3 N-chloroimides. The 3 N-chloroimides are N-chlorophthalimide, N-chlorosuccinimide, and N-chlorosaccharin, all of which have recently been developed as potential oxidimetric titrants for use in aqueous acetic acid medium. The proposed excess back-titration methods have advantages over existing methods in terms of ease of extraction into aqueous acetic acid layer, shorter reaction time of NCSA method, and stability of N-chloroimides in solid state.

Absorption of Herbicides by Soybean Seeds and Their Influence on Emergence and Seedling Growth

Weed Science ◽  
1972 ◽  
Vol 20 (5) ◽  
pp. 506-510 ◽  
Author(s):  
R. E. Phillips ◽  
D. B. Egli ◽  
L. Thompson
Keyword(s):  
Acetic Acid ◽  
Aqueous Solutions ◽  
Potassium Salt ◽  
Soybean Seeds ◽  
Experimental Procedure ◽  
Low Concentrations ◽  
High Concentrations ◽  
Shoot Weight ◽  
Total Oil ◽  
Dichlorophenoxy Acetic Acid

The total quantity and concentration of six herbicides, isopropylm-chlorocarbanilate (chlorpropham), 2-chloro-4-(ethylamino)-6-(isopropylamino-s-triazine (atrazine), 3-(3,4-dichlorophenyl)-1-methoxy-1-methylurea (linuron), 2-chloro-2′,6′-diethyl-N-(methoxymethyl)acetanilide (alachlor), 3-amino-2,5-dichlorobenzoic acid (chloramben), and (2,4-dichlorophenoxy)acetic acid (2,4-D), in unaerated, aqueous solutions absorbed by seeds of 11 soybean(Glycine max(L.) Merr.) strains were measured. Mechanism of movement of the herbicides from the aqueous solutions to the seeds in the experimental procedure employed was diffusion. Total quantity and concentration of herbicide found in the seeds differed significantly for both herbicides and soybean strains. Total quantity of herbicide absorbed was determined by total oil and percent oil of the seeds. The capacity of the seeds to absorb a given herbicide was more closely related to percent oil of the seeds than to total oil of the seeds. The emergence and seedling shoot weight of ‘Cutler’ soybeans were not affected appreciably by concentrations of linuron, atrazine, and chloramben (potassium salt) but were reduced by high concentrations of chlorpropham and alachlor and relatively low concentrations of 2,4-D (potassium salt) in the seeds.

scholarly journals Kinetics and mechanism of the Oxidative regeneration of Carbonyl Compounds from Phenylhydrazones by Tetramminecopper(2+) Bis (Permanganate)

2003 ◽  
Vol 2003 (4) ◽  
pp. 184-185
Author(s):  
Raghvendra Shukla ◽  
László Kótai ◽  
Pradeep K. Sharma ◽  
Kalyan K. Banerji
Keyword(s):  
Acetic Acid ◽  
Carbonyl Compounds ◽  
Kinetics And Mechanism ◽  
Aqueous Acetic Acid ◽  
Acid Proceeds ◽  
Oxidative Regeneration ◽  
Rate Determining Step ◽  
Activated Complex

The oxidation of aldo- and keto-phenylhydrazones by tetraamminecopper(2+) bis(permanganate) (TACP), in aqueous acetic acid, proceeds through a mechanism involving the formation of a cyclic activated complex, in the rate-determining step.

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