ChemInform Abstract: THE SOLVENT EFFECT ON DI-TERT-BUTYL NITROXIDE. A DIPOLE-DIPOLE MODEL FOR POLAR SOLUTES IN POLAR SOLVENTS

1979 ◽  
Vol 10 (32) ◽  
Author(s):  
A. H. REDDOCH ◽  
S. KONISHI
Keyword(s):  
Solvent Effect ◽  
Dipole Model ◽  
Polar Solvents ◽  
Tert Butyl ◽  
Polar Solutes

scholarly journals Determination of the dipole moments of some polar liquids dissolved in polar solvents

1969 ◽  
Vol 47 (20) ◽  
pp. 3767-3771 ◽  
Author(s):  
H. A. Rizk ◽  
N. Youssef ◽  
H. Grace
Keyword(s):  
Dipole Moments ◽  
Butyl Alcohol ◽  
Polar Solvents ◽  
Tert Butyl ◽  
Tert Butyl Alcohol ◽  
Initial Decrease ◽  
Interacting Systems ◽  
Solvent Molecules ◽  
Onsager Equation

The application of a modified form of the Onsager equation at the condition of infinite dilution of a polar solute in a polar solvent leads to reasonable dipole moments for water, pyridine, acetone, tert-butyl alcohol, n-butyl alcohol, and β-octyl alcohol, except in the case of water in tert-butyl alcohol at 30 and 40 °C and the case of acetone in n-butyl alcohol at 30 to 50 °C. The initial decrease of the dielectric constant of solvent by addition of solute in each of these two cases is associated with a reduction in the Kirkwood g-factor of solute. In all 12 systems investigated, strong hydrogen bonding occurs between solute and solvent molecules and often between solvent molecules themselves. It is thought that this equation must fail when short-range interactions assume predominant importance, but why it works so well for those cases which are also strongly interacting systems is not clear.

Thermodynamic studies in solution. Part IV. Solvent effect on the solvolysis of tert-butyl chloride. A new treatment of the experimental data

1979 ◽  
Vol 57 (5) ◽  
pp. 500-502 ◽  
Author(s):  
Joaquim Jose Moura Ramos ◽  
Jacques Reisse ◽  
M. H. Abraham
Keyword(s):  
Free Energy ◽  
Solvent Effect ◽  
Free Energies ◽  
Butyl Chloride ◽  
Activation Free Energy ◽  
Tert Butyl ◽  
New Treatment ◽  
The One ◽  
Activated Complex ◽  
Tert Butyl Chloride

A new treatment of the solvent effect on the solvolysis of tert-butyl chloride is proposed. This treatment is based on activation free energy measurements and on transfer free energy measurements of the reactant (R) on the one hand and of a model (M) of the activated complex (AC) on the other hand. Solute–solvent interaction free energies for the reactant, the activated complex and the model compound are estimated. This estimation involves the calculation of the free energy of cavity formation of these various solutes (R, AC, and M) in all the solvents. These cavity terms, which are a function of the cohesive properties of the solvent and of the surface of the cavity do not reflect the electronic structure of the solute whereas the interaction free energy term does. The method we propose can be described as a new 'experimental' approach for the study of the charge separation in an activated complex.

A Quantitative Investigation of the Ozonolysis Reaction. XVIII. A Kinetic Study of the Ozone Attack on Phenylethylenes

1973 ◽  
Vol 51 (20) ◽  
pp. 3398-3402 ◽  
Author(s):  
H. Henry ◽  
M. Zador ◽  
S. Fliszár
Keyword(s):  
Liquid Phase ◽  
Solvent Effect ◽  
Kinetic Study ◽  
Temperature Effect ◽  
Reaction Rates ◽  
Quantitative Investigation ◽  
Polar Solvents ◽  
Absolute Reaction

Absolute reaction rates for the ozonolysis of phenylethylenes in the liquid phase indicate: (i) a Hammett dependence, with [Formula: see text], for the ring-substituted trans stilbenes, (ii) a solvent effect, whereby the ozone attack is promoted by polar solvents, and (iii) no temperature effect between 15 and 35 °C, thus indicating [Formula: see text].

Electron exchange by hexakis(tert-butyl isocyanide)- and hexakis(cyclohexyl isocyanide)manganese(I,II). Solvent effect on the rate constant and the volume of activation

1988 ◽  
Vol 27 (16) ◽  
pp. 2893-2897 ◽  
Author(s):  
Martin Stebler ◽  
Roger M. Nielson ◽  
William F. Siems ◽  
John P. Hunt ◽  
Harold W. Dodgen ◽  
...  
Keyword(s):  
Solvent Effect ◽  
Rate Constant ◽  
Electron Exchange ◽  
Tert Butyl

THE CIS-TRANS ISOMERIZATION OF AZOBENZENE IN SOLUTION

1950 ◽  
Vol 28b (4) ◽  
pp. 140-155 ◽  
Author(s):  
C. A. Winkler ◽  
J. Halpern ◽  
G. W. Brady
Keyword(s):  
Activation Energy ◽  
Internal Pressure ◽  
Solvent Effect ◽  
Chemical Kinetics ◽  
Linear Relation ◽  
Mixed Solvents ◽  
Square Root ◽  
Polar Solvents ◽  
Trans Isomerization ◽  
Kinetics Of

Relations for the solvent effect on the rate of a unimolecular, nonionic reaction are derived, using existing theories of solutions and of chemical kinetics. The kinetics of the cis-trans isomerization of azobenzene were investigated in 16 pure solvents. A linear relation between the activation energy, E, and the square root of the internal pressure of the solvent, (P′S)1/2 was found, in agreement with the theory. Linear relations between log A and E, and between log k and (P′S)1/2 were also found, but the results for the reaction in highly polar solvents deviated significantly from these relations. The kinetics of the reaction in mixed solvents indicate that the azobenzene is preferentially surrounded by the component in which it is more readily soluble.

scholarly journals Catalytic Direct Amidations in tert-Butyl Acetate Using B(OCH2CF3)3

2019 ◽  
Author(s):  
Charlotte Coomber ◽  
Victor Laserna ◽  
Liam Martin ◽  
Peter Smith ◽  
Helen C. Hailes ◽  
...  
Keyword(s):  
Aromatic Hydrocarbons ◽  
Butyl Acetate ◽  
Medicinal Chemistry ◽  
Research Effort ◽  
Formation Processes ◽  
Polar Solvents ◽  
Tert Butyl ◽  
Amidation Reaction ◽  
Direct Amidation ◽  
Measured Process

Catalytic direct amidation reactions have been the focus of considerable recent research effort, due to the widespread use of amide formation processes in pharmaceutical synthesis. However, the vast majority of catalytic amidations are performed in non-polar solvents (aromatic hydrocarbons, ethers) which are typically undesirable from a sustainability perspective, and are often poor at solubilising polar carboxylic acid and amine substrates. As a consequence, most catalytic amidation protocols are unsuccessful when applied to polar and/or functionalised substrates of the kind commonly used in medicinal chemistry. In this paper we report a practical and useful catalytic direct amidation reaction using tert-butyl acetate as the reaction solvent. The use of an ester solvent offers improvements in terms of safety and sustainability, but also leads to an improved reaction scope with regard to polar substrates and less nucleophilic anilines, both of which are important components of amides used in medicinal chemistry. An amidation reaction was scaled up to 100 mmol and proceeded with excellent yield and efficency, with a measured process mass intensity of 8.<br>

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