Formation of anthracene cation radicals from 9,10-dihydro-9,10-epidioxyanthracene derivatives; peroxide-initiated cationic polymerization of styrene in liquid sulphur dioxide

1976 ◽  
pp. 87 ◽  
Author(s):  
Noburu Kakeya ◽  
Masatomo Nojima ◽  
Niichiro Tokura
Keyword(s):  
Sulphur Dioxide ◽  
Cationic Polymerization ◽  
Cation Radicals ◽  
Liquid Sulphur

Paramagnetic Intermediates in Oxidative Coupling Reactions of Tertiary Aromatic Amines in Liquid Sulphur Dioxide

1974 ◽  
Vol 29 (5-6) ◽  
pp. 403-407 ◽  
Author(s):  
M. Donbavand ◽  
H. Möckel
Keyword(s):  
Sulphur Dioxide ◽  
Oxidative Coupling ◽  
Aromatic Amines ◽  
Coupling Reactions ◽  
Oxidation Reactions ◽  
Cation Radicals ◽  
Radical Intermediates ◽  
Liquid Sulphur ◽  
Oxidative Coupling Reactions ◽  
Coupling Processes

Results are presented which complement earlier studies on oxidative coupling processes in aromatic amines and demonstrate strikingly the ease with which such reactions take place in liquid sulphur dioxide. Further, yields and stability of the intermediate cation radicals in this solvent compared with others of similar dielectric constant implies the participation of ionising forces not directly connected with dielectric properties. It is suggested that liquid SO2 may prove a very useful solvent in which to study radical intermediates of many oxidation reactions.

Formation of Radical Intermediates in Sulphur Dioxide Solutions of Tertiary Aliphatic Amines

1974 ◽  
Vol 29 (11-12) ◽  
pp. 742-749 ◽  
Author(s):  
M. H. Donbavand ◽  
H. J. Möckel
Keyword(s):  
Sulphur Dioxide ◽  
Free Radical Oxidation ◽  
Molecular Iodine ◽  
Coupling Constants ◽  
Aliphatic Amines ◽  
Stable Free Radical ◽  
Radical Oxidation ◽  
Radical Intermediates ◽  
Alkyl Groups ◽  
Liquid Sulphur

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.

Inelastic neutron and light scattering studies on liquid sulphur dioxide

1993 ◽  
Vol 78 (4) ◽  
pp. 821-836 ◽  
Author(s):  
A. Chahid ◽  
M. García-Hernández ◽  
C. Prieto ◽  
F.J. Bermejo ◽  
E. Enciso ◽  
...  
Keyword(s):  
Light Scattering ◽  
Sulphur Dioxide ◽  
Inelastic Neutron ◽  
Liquid Sulphur

DIELECTRIC CONSTANTS OF LIQUID SULPHUR DIOXIDE, ETHYL CHLORIDE, AND ETHYLENE OXIDE

1957 ◽  
Vol 35 (11) ◽  
pp. 1325-1331 ◽  
Author(s):  
J. D. Nickerson ◽  
R. McIntosh
Keyword(s):  
Ethylene Oxide ◽  
Sulphur Dioxide ◽  
Dipole Moments ◽  
Dielectric Constants ◽  
Ethyl Chloride ◽  
Frequency Range ◽  
Liquid Sulphur

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 kinetics of polysulphone formation - I. The formation of 1-butene polysulphone at 25° C

1952 ◽  
Vol 212 (1108) ◽  
pp. 96-112 ◽  
Keyword(s):  
Sulphur Dioxide ◽  
Primary Process ◽  
Propagation Process ◽  
A Value ◽  
Absorption Of Light ◽  
Rate Of Reaction ◽  
Liquid Sulphur ◽  
Rate Of Absorption ◽  
Photochemical Initiation ◽  
Kinetics Of

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.

scholarly journals LXXIII.—Electrolysis of hydrogen bromide in liquid sulphur dioxide

1920 ◽  
Vol 117 (0) ◽  
pp. 693-696 ◽  
Author(s):  
Lancelot Salisbury Bagster ◽  
George Cooling
Keyword(s):  
Sulphur Dioxide ◽  
Hydrogen Bromide ◽  
Liquid Sulphur

scholarly journals From amino acid mixtures to peptides in liquid sulphur dioxide on early Earth

2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Fabian Sauer ◽  
Maren Haas ◽  
Constanze Sydow ◽  
Alexander F. Siegle ◽  
Christoph A. Lauer ◽  
...  
Keyword(s):  
Amino Acids ◽  
Sulphur Dioxide ◽  
Room Temperature ◽  
Early Earth ◽  
Peptide Bonds ◽  
Initial Reactant ◽  
Peptide Formation ◽  
Liquid Sulphur ◽  
Catalytically Active ◽  
Amino Acid Mixtures

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.

Cationic polymerization of vinyl monomers initiated by 10-methylphenothiazine cation radicals

1994 ◽  
Vol 32 (9) ◽  
pp. 1703-1710 ◽  
Author(s):  
Shigeki Nomura ◽  
Yotaro Morishima ◽  
Toshihiro Koremoto ◽  
Mikiharu Kamachi
Keyword(s):  
Cationic Polymerization ◽  
Vinyl Monomers ◽  
Cation Radicals
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