scholarly journals Calculated Third Order Rate Constants for Interpreting the Mechanisms of Hydrolyses of Chloroformates, Carboxylic Acid Halides, Sulfonyl Chlorides and Phosphorochloridates

2015 ◽  
Vol 16 (12) ◽  
pp. 10601-10623 ◽  
Author(s):  
T. Bentley
Keyword(s):  
Carboxylic Acid ◽  
Rate Constants ◽  
Third Order ◽  
Sulfonyl Chlorides ◽  
Order Rate

A kinetic investigation of the effects of molecular complexing on the acidities of some π donor carboxylic acids

1977 ◽  
Vol 55 (6) ◽  
pp. 1028-1038 ◽  
Author(s):  
Allan K. Colter ◽  
R. James Kersting
Keyword(s):  
Carboxylic Acid ◽  
Acrylic Acid ◽  
Carboxylic Acids ◽  
Rate Constants ◽  
Association Constants ◽  
Second Order ◽  
Kinetic Investigation ◽  
Rate Data ◽  
Dihydroxybenzoic Acid ◽  
Order Rate

Rates of reaction of the five π donor acids indole-3-acrylic acid (IAA), indole-5-carboxylic acid (ICA), 3,4,5-trimethoxybenzoic acid (TMBA), 2,4-dihydroxybenzoic acid (DHBA), and 3,4,5-trihydroxybenzoic acid (THBA) with 4-chlorodiphenyldiazomethane (4-ClDDM) in ethanol at 30 °C were measured in the presence of the π acceptors 1,3,5-trinitrobenzene (TNB), benzotrifuroxan (BTF), and 1,2,4,5-tetracyanobenzene (TCNB) and in the absence of acceptor. For 12 of the 13combinations studied, added acceptor produced rate enhancements. The rate data were combined with independently-determined 1:1 acceptor – donor acid association constants to obtain second-order rate constants for reaction of the 1:1 acceptor – donor acid complexes. From the increase in the rate constant resulting from complexation, estimates of the increase in Ka(H2O, 25 °C) produced by complexation were obtained for 13 acceptor – donor acid combinations. Second-order rate constants for reaction of 4-ClDDM with 10 other carboxylic acids and p-toluenesulfonic acid in ethanol at 30°C were also measured and the pattern of reactivity shown to parallel very closely that of diphenyldiazomethane.

Third-order rate constants of atmospheric importance

1983 ◽  
Vol 15 (11) ◽  
pp. 1189-1227 ◽  
Author(s):  
Roger Patrick ◽  
David M. Golden
Keyword(s):  
Rate Constants ◽  
Third Order ◽  
Order Rate

The formation and reactions of aromatic dimer cations in a high pressure photoionization source

1980 ◽  
Vol 58 (16) ◽  
pp. 1666-1672 ◽  
Author(s):  
John A. Stone ◽  
Margaret S. Lin
Keyword(s):  
High Pressure ◽  
Charge Transfer ◽  
Ionization Potential ◽  
Rate Constants ◽  
Aromatic Compounds ◽  
Third Order ◽  
Order Rate ◽  
Lower Ionization Potential ◽  
The Difference

Aromatic dimer cations (M2+) have been generated for a series of aromatic compounds in a high pressure photoionization source. Relative third order rate constants for formation of M2+ have been obtained for benzene (1.0), benzene-d6 (2.7), toluene (0.8), o-xylene (1.5), p-xylene (0.7), fluorobenzene (0.3), m-fluorotoluene (0.5), m-chlorotoluene (0.7), p-chlorotoluene (0.5), and o-methoxytoluene (0.4). These values are consistent with and supplement previous data for such systems. Reagent ion monitoring has been used to determine the relative rates of reaction of both M2+ and the monomer ions, M+, with a series of (mainly) aromatic compounds (X). Reaction of C6H6+ is by charge transfer to compounds of lower ionization potential than C6H6. (C6H6)2+ reacts only by charge transfer, if the ionization potential of X is more than 0.5 eV lower than that of benzene. When the difference is smaller, mixed dimer cations are observed which are probably formed in a switching reaction (C6H6)2+ + X → (C6H6•X)+ + C6H6.

Kinetics and mechanism of the decarboxylation of pyrimidine-2-carboxylic acid in aqueous solution

1977 ◽  
Vol 55 (13) ◽  
pp. 2478-2481 ◽  
Author(s):  
Gerald E. Dunn ◽  
Edward A. Lawler ◽  
A. Brian Yamashita
Keyword(s):  
Carbon Dioxide ◽  
Aqueous Solution ◽  
Carboxylic Acid ◽  
Rate Constants ◽  
Kinetics And Mechanism ◽  
First Order ◽  
Order Rate ◽  
Pseudo First Order ◽  
Positively Charged

Pseudo-first-order rate constants for the decarboxylation of pyrimidine-2-carboxylic acid have been determined at 65 °C in aqueous solution over the acidity range pH = 2 to H0 = −9.5. Rate constants increase rapidly from pH = 2 to H0 = −3, then remain constant. This behaviour can be accounted for by a Hammick-type mechanism in which monoprotonated pyrimidine-2-carboxylic acid loses carbon dioxide to form an ylide (stabilized by the adjacent positively charged nitrogens) which rapidly converts to pyrimidine.

Rate constants for the gaseous reactions OH + C2H4 and OH + OH

1980 ◽  
Vol 33 (7) ◽  
pp. 1425 ◽  
Author(s):  
GK Farquharson ◽  
RH Smith
Keyword(s):  
Mass Spectrometer ◽  
Hydroxyl Radicals ◽  
Rate Constant ◽  
Rate Constants ◽  
Order Rate Constant ◽  
Resonance Fluorescence ◽  
Flow Tube ◽  
Third Order ◽  
Order Rate ◽  
Wall Loss

The rate of disappearance of hydroxyl radicals (generated by H+NO2 → OH+NO) along a discharge flow tube both with and without ethene present was measured by resonance fluorescence. Stoichiometry was simultaneously measured with a mass spectrometer, the leak into which was located downstream of the resonance fluorescence cell. After allowing for loss of hydroxyl by known homogeneous reactions and for wall loss (when applicable) it was found that for OH+C2H4 the low pressure limiting third-order rate constant kter was (3.1 � 0.5)x 10-29 cm6 s-1 at approximately 298 K. In addition an estimate for the second- order rate constant for OH+OH was obtained, namely (1.7 � 0.2) × 10-12 cm3 s-1. These results are discussed in relation to previous measurements.

Investigation of CO2 and ethylethanolamine reaction kinetics in aqueous solutions using the stopped-flow technique

2013 ◽  
Vol 67 (9) ◽  
Author(s):  
Hanna Kierzkowska-Pawlak ◽  
Marta Siemieniec ◽  
Andrzej Chacuk
Keyword(s):  
Aqueous Solutions ◽  
Rate Constants ◽  
Original Method ◽  
Single Step ◽  
Stopped Flow ◽  
Third Order ◽  
Order Rate ◽  
Pseudo Second Order ◽  
Kinetics Of ◽  
Single Step Reaction

AbstractKinetics of the reaction of CO2 and ethylethanolamine (EMEA) in aqueous solutions has been studied using the stopped-flow technique with conductivity detection. Measurements were performed at 288 K, 293 K, 298 K, and 303 K. Amine concentration ranged from 10 mol m−3 to 37.5 mol m−3. The termolecular mechanism was applied to interpret the kinetic data. In this mechanism, carbamate formation occurs in a single-step reaction without the formation of a zwitterion intermediate. An original method of analyzing the experimental data was proposed allowing the derivation of pseudo second order rate constants from the measured kinetic traces. Based on these values, the third order rate constants $$\left( {k_{H_2 O} } \right)$$ of the reaction of CO2, water, and EMEA were derived and correlated by the Arrhenius equation.

Sign in / Sign up

Export Citation Format

Share Document