A new method for the determination of the relative acidities of alcohols in alcoholic solutions. The nucleophilicities and competitive reactivities of alkoxides and phenoxides

1979 ◽  
Vol 57 (20) ◽  
pp. 2747-2754 ◽  
Author(s):  
Wilkins Reeve ◽  
Charles M. Erikson ◽  
Patrick F. Aluotto
Keyword(s):  
Isopropyl Alcohol ◽  
Butyl Alcohol ◽  
New Method ◽  
Butyl Bromide ◽  
Tert Butyl ◽  
Ether Mixture ◽  
Tert Butyl Alcohol ◽  
Relative Nucleophilicity ◽  
Semiquantitative Method

A new semiquantitative method has been developed for measuring the relative acidities of methanol, ethanol, isopropyl alcohol, and tert-butyl alcohol in mixed hydroxylic solvents. A solution of the alkoxides of two alcohols in an excess of the two alcohols is allowed to react with n-butyl bromide to form a mixture of two ethers. The composition of the ether mixture is a measure of the "competitive reactivity" of thetwo alkoxides. This can be measured directly, and in theory can be factored into two components: the relative nucleophilicity and the relative basicity of the two alkoxides. Relative nucleophilicities are determined by using solutions in which phenol is one component. Knowing the competitive reactivities and nucleophilicities, the relative acidities of methanol, ethanol, isopropyl alcohol, and tert-butyl alcohol in alcoholic media are shown to be 4.4, 1.0, 0.24, and 0.21, respectively. The relative nucleophilicities of hydroxide, methoxide, ethoxide, isopropoxide, tert-butoxide, phenoxide, and m-cresoxide are 0.08, 0.82, 1.0, 0.4, 0.04, 0.46, and 0.57 respectively.

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.

Esters chromiques dérivés du tertiobutanol

1976 ◽  
Vol 54 (4) ◽  
pp. 572-575
Author(s):  
Jean-Marie Hachey ◽  
Hélène Ghali ◽  
Jean-Baptiste Savard
Keyword(s):  
Chromium Content ◽  
Chromium Trioxide ◽  
Butyl Alcohol ◽  
Tert Butyl ◽  
Tert Butyl Alcohol

The composition of the mixture of chromate esters obtained from the reaction between tert-butyl alcohol and increasing amounts of chromium trioxide has been calculated from the pmr spectrum and confirmed through the determination of the chromium content of these mixtures. The chromate esters formed are the ditertiarybutyl mono-, di-, and trichromate.

Influence of solvent on kinetics of reactions of Cr(II) ions

1981 ◽  
Vol 46 (7) ◽  
pp. 1554-1559 ◽  
Author(s):  
Peter Ševčík ◽  
Ján Tkáč
Keyword(s):  
Mole Fraction ◽  
Methyl Alcohol ◽  
Maleic Acid ◽  
Redox Reaction ◽  
Isopropyl Alcohol ◽  
Butyl Alcohol ◽  
Dichloroacetic Acid ◽  
Tert Butyl ◽  
Tert Butyl Alcohol ◽  
Kinetics Of

This paper deals with the study of redox reactions of Cr(II) ions with hydroxylamine, hydrazoic acid, maleic acid, di- and trichloroacetic acids in so-called typically aqueous mixtures of water with methyl alcohol, isopropyl alcohol, or tert-butyl alcohol. The kinetics of the redox reaction with dichloroacetic acid was studied also in the medium of aqueous acetone and in a typically nonaqueous medium water-acetonitrile. The dependences of activation Gibbs energies on the mole fraction of the nonaqueous component have no minima and maxima characteristic for the thermodynamic behaviour of the mentioned binary systems. However, the change of the activation Gibbs energy with the mole fraction of tert-butyl alcohol is not monotonous with all the studied reactions of Cr(II) ions. At a constant mole fraction of the nonaqueous component, the usual trend of the influence on the rate constants decreases in the sequence tert-butyl alcohol > isopropyl alcohol > methyl alcohol. Tert-butyl alcohol hinders most strongly the redox reaction with trichloroacetic acid, whereas it accelerates the reaction of Cr(II) ions with maleic acid and hydroxylamine.

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