Author(s)

Sergio L. Laurella, Manuel González Sierra, Jorge J. P. Furlong, Patricia E. Allegretti

Laboratorio LADECOR, División Química Orgánica, Departamento de Química, Facultad de Ciencias Exactas, Universidad Nacional de La Plata (UNLP), La Plata, Argentina.

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.

β-Ketoamides; Keto-Enol Equilibrium; Nuclear Magnetic Resonance Spectroscopy

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.