Reactions in liquid sulphur dioxide. Part I.—Exchange of oxygen between liquid sulphur and thionyl chloride

1950 ◽  
Vol 46 (0) ◽  
pp. 1039-1041 ◽  
Author(s):  
E. C. M. Grigg ◽  
I. Lauder
1974 ◽  
Vol 29 (11-12) ◽  
pp. 742-749 ◽  
Author(s):  
M. H. Donbavand ◽  
H. J. Möckel

The addition of molecular iodine to solutions of tertiary aliphatic amines in liquid sulphur dioxide is found to result in the formation of stable free radical oxidation intermediates. In triethylamine solutions, oxidised under these conditions, aromatisation appears to take place to produce a pyridinyl radical. Radicals formed from N-ethyldimethylamine, Ν,Ν-diethylmethylamine and tri-n-propylamine on the other hand appear to be essentially aliphatic in character, with two of the N-alkyl groups intact. The magnitude of the measured coupling constants however, implies some delocalisation in the “damaged” alkyl group, possibly via a tautomeric mechanism. A number of mechanistic possibilities are explored to account for the roles played by iodine and sulphur dioxide in these reactions.


1993 ◽  
Vol 78 (4) ◽  
pp. 821-836 ◽  
Author(s):  
A. Chahid ◽  
M. García-Hernández ◽  
C. Prieto ◽  
F.J. Bermejo ◽  
E. Enciso ◽  
...  

1957 ◽  
Vol 35 (11) ◽  
pp. 1325-1331 ◽  
Author(s):  
J. D. Nickerson ◽  
R. McIntosh

Dielectric constants of sulphur dioxide, ethyl chloride, and ethylene oxide have been measured over the frequency range 9 to 92 Mc./second and at temperatures between −35° and +20 °C. Dipole moments computed from the Debye, Onsager, and Kirkwood equations are reported and compared with the moments which are known from measurements on the gaseous substances.


The formation of 1-butene polysulphone from mixtures of liquid sulphur dioxide and 1-butene has been investigated dilatometrically at 25° C. Photochemical and silver nitrate initiation have been used, most of the work being carried out in mixtures containing an excess of sulphur dioxide. There is a discrepancy, in the case of photochemical initiation, between the molecular weight as estimated from the intrinsic viscosity of the polymer, and that deter­mined from the rate of reaction and rate of absorption of light. This discrepancy is ascribed to an inefficient primary process. The variation of rate with initiator, monomer and retarder concentrations has been investigated. The initiator exponent has a value intermediate between 0.5 and 1.0, indicating the occurrence of at least two termination processes. Kinetic expressions have been deduced for various possible termination mechanisms, and. in order to obtain agreement with experiment it is necessary to assume that the propagation process involves the addition to the growing chain of a 1:1 molecular complex of 1-butene and sulphur dioxide.


1920 ◽  
Vol 117 (0) ◽  
pp. 693-696 ◽  
Author(s):  
Lancelot Salisbury Bagster ◽  
George Cooling

2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Fabian Sauer ◽  
Maren Haas ◽  
Constanze Sydow ◽  
Alexander F. Siegle ◽  
Christoph A. Lauer ◽  
...  

AbstractThe formation of peptide bonds is one of the most important biochemical reaction steps. Without the development of structurally and catalytically active polymers, there would be no life on our planet. However, the formation of large, complex oligomer systems is prevented by the high thermodynamic barrier of peptide condensation in aqueous solution. Liquid sulphur dioxide proves to be a superior alternative for copper-catalyzed peptide condensations. Compared to water, amino acids are activated in sulphur dioxide, leading to the incorporation of all 20 proteinogenic amino acids into proteins. Strikingly, even extremely low initial reactant concentrations of only 50 mM are sufficient for extensive peptide formation, yielding up to 2.9% of dialanine in 7 days. The reactions carried out at room temperature and the successful use of the Hadean mineral covellite (CuS) as a catalyst, suggest a volcanic environment for the formation of the peptide world on early Earth.


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