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Substituent, Temperature and Solvent Effects on the Keto-Enol EQUILIBRIUM in β-Ketoamides: A Nuclear Magnetic Resonance Study

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DOI: 10.4236/ojpc.2013.34017    5,892 Downloads   10,276 Views   Citations

ABSTRACT

Substituent, temperature and solvent effects on tautomeric equilibria in several β-ketoamides have been investigated by means of nuclear magnetic resonance spectroscopy (NMR). Keto-enol equilibrium predominates over the amide-imidol one. The relative stability of the individual tautomers and the corresponding equilibrium shifts are explained considering electronic and steric effects and tautomer stabilization via internal hydrogen bonds. In solution, these compounds exist mainly as ketoamide and Z-enolamide tautomers, both presenting intramolecular hydrogen bonds.

Conflicts of Interest

The authors declare no conflicts of interest.

Cite this paper

S. Laurella, M. Sierra, J. Furlong and P. Allegretti, "Substituent, Temperature and Solvent Effects on the Keto-Enol EQUILIBRIUM in β-Ketoamides: A Nuclear Magnetic Resonance Study," Open Journal of Physical Chemistry, Vol. 3 No. 4, 2013, pp. 138-149. doi: 10.4236/ojpc.2013.34017.

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