Relative Basicities of Carboxylate Lone Pairs in Aqueous-Solution

by Pranata, J.

Relative basicities of the lone pairs of the acetate ion have been determined using ab initio calculations for the gas phase and Monte Carlo simulations for the aqueous phase. The syn lone pair is found to be more basic by only 1.25 pK(a) units. This small difference is the result of a large intrinsic preference for the syn conformer of the conjugate acid in the gas phase, offset by an almost equally large preferential solvation of the anti conformer in the aqueous phase. The better solvation of the anti conformer is due to stronger solute-solvent interactions.

Journal
Journal of Computational Chemistry
Volume
14
Issue
6
Year
1993
Start Page
685-690
URL
https://dx.doi.org/10.1002/jcc.540140609
ISBN/ISSN
1096-987X; 0192-8651
DOI
10.1002/jcc.540140609