Empirical correlations of partial molar volumes at infinite dilution of organic solutes and transition states for SN1 and SN2 ethanolysis of alkyl halides

Abstract

Activation volumes are measured to be -21 to -29 cm3 mol-' for the ethanolysis of t-butyl chloride and bromide and methyl bromide in ethanol at 31 8.1 5 K. Partial molar volumes at infinite dilution are measured for 34 organic solutes. Partial molar volumes of the transition states can be treated in the same way as those of common solutes, in which the partial molar volume of each solute is compared with that of an alkane having the same van der Waals volume. The volume changes caused by the molecularity of reaction and the intermolecular interaction during the activation process are discussed.* 101 325 Pa = 1 atm.

Activation and Reaction Volumes in Solution. 3

“…Solvolysis experiments by Itsuki 558,559 and others show mostly normal values understandable in terms of Drude-Nernst theory, as explained in our earlier reviews (entries . Thus, in ethanol, substantially more negative activation volumes are found than in water, as expected from the less polar nature of the alcohol; the tert-butyl chloride is more strongly accelerated than the bromide because of the smaller size of the chloride anion.…”

Experimental P–ρ–T Data and Modeling for Butan-2-ol + n-Octane or n-Decane in the Ranges of 313.15–353.15 K and 0.1–20 MPa

“…As illustrated in Figures and , a significant positive excess volume is observed for both systems. This behavior is generally expected of alcohol + alkane systems ,,− of these chain lengths as stated above and again is attributed to the declustering of self-associated alcohol multimer series by the nonpolar alkane, and the interaction between homomorphs of the alcohols and the alkanes on the addition of the nonpolar solvent is expected to decluster the alcohol complexes, contributing to an expansion in the volume upon mixing as the alcohol molecules occupy more space as monomers than as multimers. The interaction energy between the alcohol homomorphs and the alkane, which includes dipole–dipole interactions, is expected to contribute to a positive excess volume. , The negative V E effects of free volume changes and interstitial rearrangement are smaller than the positive contributions.…”

CHAPTER 8. Partial Molar Volumes of Non-Ionic Solutes at Infinite Dilution

“…48 Data are available for amines dissolved in heptane, 49 benzene, 50,51 cyclohexane, 51 trichloromethane and tetrachloromethane, 52 and several other organic solvents. 53 Standard molar volumes of the derivatives of dibenzothiophene dissolved in alkanes and cyclohexane were measured by de Oliveira et al 54 Experimental results for alkanes, haloalkanes, mono-and polyhydric aliphatic alcohols, ethers, and ether alcohols dissolved in ethanol were presented by Itsuki et al 55 Standard molar volumes of water as a solute dissolved in organic solvent (aromatic hydrocarbons, 5,56 1-alkanols, 56-59 cyclohexanol, 58 propylene carbonate, 60,61 and others 59,60 ) have also been studied.…”