Results 241 to 250 of about 11,464 (289)

Catalysis in aprotic solvents. Effect of the polarity of the catalyst.

Tetrahedron Letters, 1981
Abstract The catalytic constants for the n -butylaminolysis of sultones in aprotic-apolar solvents are linearly correlated with a combination of the hydrogen-bonding parameter and the polarity parameter of the catalyst.
CIUFFARIN E, ISOLA M, LEONI, PIERO
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Spin-Trapping of the Superoxide Radical in Aprotic Solvents

Free Radical Research Communications, 1991
The superoxide adduct of 5,5-dimethyl-l-pyrroline-N-oxide (DMPO) has been detected by EPR spectroscopy in aprotic solvents using KO2 solubilized in 18-crown-6-ether as a source of superoxide. The EPR hyperfine splitting constants of the DMPO-superoxide adduct were as follows: benzene/toluene (aN = 12.65 G; aH beta = 10.4 G; aH gamma = 1.3 G); heptane ...
K, Reszka, C F, Chignell
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Electrolyte solvation in aprotic solvents

Journal of Power Sources, 1989
Abstract The nature of specific ionsolvent, ionion and solventsolvent interactions is reviewed in the context of their relation to the development of lithium batteries. For aprotic solvents of permittivities > ≈ 15, the “medium effect” has been found to offer insights into basic problems ( e.g.
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Photochemistry of 5-aminoquinoline in protic and aprotic solvents

Spectrochimica Acta Part A: Molecular and Biomolecular Spectroscopy, 2011
Photophysical properties of 5-aminoquinoline (5AQ) have been investigated in various non-polar and polar (protic and aprotic) solvents using steady state and time resolved fluorescence. In aprotic solvents, the spectral maxima depend on the polarity. However, in protic solvents both the fluorescence intensity as well decay time show decrease depending ...
Jagat P, Bridhkoti, Hirdyesh, Mishra, H C, Joshi, Sanjay, Pant   +3 more
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Base Catalysis of Aromatic Nucleophilic Substitution Reactions in Aprotic and Dipolar Aprotic Solvents

Bulletin des Sociétés Chimiques Belges, 1982
For base-catalysed aromatic nucleophilic substitution reactions in benzene, catalysis by added base is observed irrespective of whether the catalyst is a stronger or a weaker base than the nucleophile. In acetonitrile, catalysis is only observed if the catalyst has either approximately the same strength or is a stronger base than the nucleophile. These
Titus O. Bamkole, Jack Hirst, Ikenna Onyido   +2 more
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Solvatochromism of fluorescein in aqueous aprotic solvents

Journal of Molecular Liquids, 2016
Abstract Fluorescein solvatochromism was studied in pure aprotic solvents dimethylsulfoxide, N,N-dimethylformamide, acetonitrile and acetone, and their aqueous mixtures. The type and extent of solvent effects were identified and interpreted based on the electronic structure of fluorescein and the nature of the solvent.
Fereshteh Naderi, Ali Farajtabar
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Anodic oxidation of furans in aprotic solvents

Electrochimica Acta, 1984
Abstract The anodic oxidation of furans in the presence of substituted 1,4-napthoquinones leads to coupling of the two. In the absence of the quinones, furan oligomers are formed. Further oxidation of these oligomers leads to the formation of conductive polymer films at the electrode surface.
S. Pons, A.Scott Hinman
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Sulfamides and sulfonamides as polar aprotic solvents

The Journal of Organic Chemistry, 1987
L'etude est faite sur 5 tetraalkylsulfamides, une N,N-dialkylsulfonamide, deux diamides sulfureuse, et un ...
Herman G. Richey, Julius Farkas
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Electrode Kinetics in Nonaqueous Aprotic Solvents

Journal of The Electrochemical Society, 1985
Etudes, a l'aide de la methode d'impedance faradique, de la cinetique de reduction de Na + en presence d'une electrode a goutte de mercure, dans 4 solvants aprotiques (carbonate de propylene, DMF, DMSO et acetonitrile)
Jacob Jorné, Purnachandra G. Pai
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The Solubility of Polyimides in Polar Aprotic Solvents

High Performance Polymers, 2002
Activity coefficients and Gibbs free energies of mixing were calculated for aromatic polyimides in various polar aprotic solvents. Group additivity approaches were used to derive approximate solubility parameters for the polymers. Free energies of mixing were found to be negative, and limiting activity coefficients were indicative of very strong ...
David Suleiman-Rosado, Jeffrey A. Hinkley   +1 more
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