THE METAL-CATALYZED AUTOXIDATION OF TETRALIN: IV. THE EFFECT OF SOLVENT AND TEMPERATURE

1964 ◽  
Vol 42 (11) ◽  
pp. 2424-2433 ◽  
Author(s):  
Y. Kamiya ◽  
K. U. Ingold

The limiting rate of oxidation of tetralin catalyzed by cobalt, manganese, and copper decanoates has been measured in 12 solvents at 65 °C. This rate is generally determined by the kinetic condition that the hydroperoxide reaches a steady-state concentration but the experimental rates are smaller than expected in some solvents. Both cobalt and manganese are able to terminate reaction chains and they therefore act as inhibitors of the oxidation at high concentrations. The ratio of the propagation rate constant (k3) to the square root of the termination rate constant (k6) for the oxidation of tetralin in acetic acid solution is given by[Formula: see text]


Author(s):  
Bart G. Manders ◽  
Gr�gory Chambard ◽  
Wieb J. Kingma ◽  
Bert Klumperman ◽  
Alex M. Van Herk ◽  
...  






2013 ◽  
Vol 450 (1) ◽  
pp. 119-121 ◽  
Author(s):  
V. A. Rozentsvet ◽  
V. G. Kozlov ◽  
N. A. Korovina ◽  
I. A. Novakov


1970 ◽  
Vol 48 (13) ◽  
pp. 2031-2034 ◽  
Author(s):  
G. Löhr ◽  
S. Bywater

The propagation reaction in the anionic polymerization of styrene in oxepane has been studied as a function of temperature and concentration of polystyrylsodium. Conductance measurements on polystyrylsodium were also made together with determinations of density, viscosity, dielectric constant, and dipole moment of oxepane itself. The measurements enabled the propagation rate constant to be determined of the polystyryl anion at 30 °C and of the ion-pair over a wide temperature range. The results have been compared with those obtained in tetrahydrofuran and tetrahydropyran.



1983 ◽  
Vol 213 (3) ◽  
pp. 727-732 ◽  
Author(s):  
E Grazi ◽  
A Ferri ◽  
S Cino

We compared the properties of the nuclei that accumulate in 7.5 mM-KCl in ATP-G-actin solutions and of the oligomers that are formed by sonication of either G-actin or F-actin. We found that the ability of the above species to prime the polymerization of actin decays with different rates. The nuclei are stable in 7.5 mM-KCl (they decay with a rate constant of 1.5 X 10(-3) s -1 at pH 7.8 at 22 degrees C in the absence of KCl). The oligomers formed by sonication of either G-actin or F-actin, once the sonication is stopped, revert to simpler structures or evolve into F-actin, depending on the KCl concentration in which they are kept. In 10.5 mM-KCl at pH 7.8 at 22 degrees C their priming ability decays with a rate constant of 6 X 10(-3) s -1. We propose that the nuclei that form spontaneously in 7.5 mM-KCl are not directly susceptible to elongation. They must first be converted into activated nuclei, which exist in very low concentration at the steady state. The activated nuclei are directly susceptible to elongation, they have a short life and they decay rapidly into the ground state unless the elongation reaction occurs. Sonication displaces the steady-state concentration in favour of the activated state.



1966 ◽  
Vol 44 (10) ◽  
pp. 1113-1118 ◽  
Author(s):  
J. A. Howard ◽  
K. U. Ingold

Absolute rate constants for the copolymerization of α-methylstyrene and oxygen have been measured from 13 to 50 °C. The propagation and termination rate constants can be represented by[Formula: see text]Experiments with 2,6-di-t-butyl-4-methylphenol at 65 °C have shown that C6H5C(CH3):CH2 and C6H5C(CD3):CD2 have the same propagation rate constant but that chain termination involves a deuterium isotope effect (kt)H/(kt)D ≈ 1.5.Absolute rate constants for the copolymerization of oxygen with β-methylstyrene and with indene at 30 °C showed that a significant fraction of the oxidation chains were terminated by a kinetically first order process (rate constant kx). The rate constants for β-methylstyrene and indene at 30 °C are kp = 51 and 142 l mole−1 s−1, kt = 1.6 × 107 and 2.5 × 107 l mole−1 s−1, and kx = 0.61 and 1.2 s−1, respectively. The propagation rate constant for indene can be separated into a rate constant for the copolymerization with oxygen (kadd = 128 l mole−1 s−1) and a rate constant for hydrogen atom abstraction (kabstr = 14 l mole−1 s−1). In the presence of heavy water the first order process for indene had a deuterium isotope effect (kx)/(kx)D2O ≈ 3.



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