A Greatly Under-Appreciated Fundamental Principle of Physical Organic Chemistry
Abstract
:1. Introduction
2. Results and Discussion
2.1. General Acid Catalysis in Strong Acid Media
2.2. Ether Hydrolyses
2.3. Amide Hydrolyses
2.4. Ester Hydrolyses
2.5. Mechanisms Involving Chains of Water Molecules
3. Conclusions
- If a species does not have a finite lifetime in the solution in which the reaction is performed it cannot be a reaction intermediate. No primary or secondary carbocations in aqueous media; only T0, no T+, T−, T± or T2− tetrahedral intermediates.
- Positive or negative charge, if present, will be as delocalized as possible during the reaction, especially in reaction intermediates, often into the aqueous solvent. A highly electronegative atom like oxygen is simply not going to support a positive charge all by itself. O+ is almost as unlikely as F+!
- Also, reactions will be unimolecular, as far as possible, for entropic reasons (SN1 favored over SN2); however, mechanisms involving chains of water molecules are favored in aqueous media thanks to the highly structured nature of water and the Grotthuss process.
Acknowledgments
- Conflict of InterestThe author declares no conflict of interest.
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Cox, R.A. A Greatly Under-Appreciated Fundamental Principle of Physical Organic Chemistry. Int. J. Mol. Sci. 2011, 12, 8316-8332. https://doi.org/10.3390/ijms12128316
Cox RA. A Greatly Under-Appreciated Fundamental Principle of Physical Organic Chemistry. International Journal of Molecular Sciences. 2011; 12(12):8316-8332. https://doi.org/10.3390/ijms12128316
Chicago/Turabian StyleCox, Robin A. 2011. "A Greatly Under-Appreciated Fundamental Principle of Physical Organic Chemistry" International Journal of Molecular Sciences 12, no. 12: 8316-8332. https://doi.org/10.3390/ijms12128316