Ab initio and 17O NMR studies of the substituent effects on the tautomeric equilibrium in 6-X-1H-2-pyridones

17O chemical shifts are found to be highly sensitive probes in the study of keto-enol tautomeric equilibria due to the strong sensitivity of these shifts to the coordination of the oxygen atom. The large shielding effect observed, both experimentally and theoretically, for the carbonyl oxygen atom i...

Descripción completa

Guardado en:
Detalles Bibliográficos
Autores principales: Facelli, J.C., Orendt, A.M., Contreras, R.H., Tufró, M.F., De Kowalewski, D.G.
Formato: Artículo publishedVersion
Publicado: 1992
Acceso en línea:http://hdl.handle.net/20.500.12110/paper_00223654_v96_n20_p7895_Facelli
https://repositoriouba.sisbi.uba.ar/gsdl/cgi-bin/library.cgi?a=d&c=artiaex&d=paper_00223654_v96_n20_p7895_Facelli_oai
Aporte de:
id I28-R145-paper_00223654_v96_n20_p7895_Facelli_oai
record_format dspace
spelling I28-R145-paper_00223654_v96_n20_p7895_Facelli_oai2024-08-16 Facelli, J.C. Orendt, A.M. Contreras, R.H. Tufró, M.F. De Kowalewski, D.G. 1992 17O chemical shifts are found to be highly sensitive probes in the study of keto-enol tautomeric equilibria due to the strong sensitivity of these shifts to the coordination of the oxygen atom. The large shielding effect observed, both experimentally and theoretically, for the carbonyl oxygen atom in 2-pyridone suggests that the carbonyl π-electronic system is undergoing a strong conjugation with the formal C3=C4 double bond and/or the nitrogen lone pair. A Cl or NH2 substitution at position 6 of the pyridine ring shifts the tautomeric equilibrium toward the 2-hydroxypyridine form, while a CH3 substitution results in the keto form being predominant, as is the case in the parent compound. © 1992 American Chemical Society. Fil:Facelli, J.C. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales; Argentina. Fil:Contreras, R.H. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales; Argentina. Fil:Tufró, M.F. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales; Argentina. application/pdf http://hdl.handle.net/20.500.12110/paper_00223654_v96_n20_p7895_Facelli info:eu-repo/semantics/openAccess http://creativecommons.org/licenses/by/2.5/ar Journal of Physical Chemistry 1992;96(20):7895-7898 Ab initio and 17O NMR studies of the substituent effects on the tautomeric equilibrium in 6-X-1H-2-pyridones info:eu-repo/semantics/article info:ar-repo/semantics/artículo info:eu-repo/semantics/publishedVersion https://repositoriouba.sisbi.uba.ar/gsdl/cgi-bin/library.cgi?a=d&c=artiaex&d=paper_00223654_v96_n20_p7895_Facelli_oai
institution Universidad de Buenos Aires
institution_str I-28
repository_str R-145
collection Repositorio Digital de la Universidad de Buenos Aires (UBA)
description 17O chemical shifts are found to be highly sensitive probes in the study of keto-enol tautomeric equilibria due to the strong sensitivity of these shifts to the coordination of the oxygen atom. The large shielding effect observed, both experimentally and theoretically, for the carbonyl oxygen atom in 2-pyridone suggests that the carbonyl π-electronic system is undergoing a strong conjugation with the formal C3=C4 double bond and/or the nitrogen lone pair. A Cl or NH2 substitution at position 6 of the pyridine ring shifts the tautomeric equilibrium toward the 2-hydroxypyridine form, while a CH3 substitution results in the keto form being predominant, as is the case in the parent compound. © 1992 American Chemical Society.
format Artículo
Artículo
publishedVersion
author Facelli, J.C.
Orendt, A.M.
Contreras, R.H.
Tufró, M.F.
De Kowalewski, D.G.
spellingShingle Facelli, J.C.
Orendt, A.M.
Contreras, R.H.
Tufró, M.F.
De Kowalewski, D.G.
Ab initio and 17O NMR studies of the substituent effects on the tautomeric equilibrium in 6-X-1H-2-pyridones
author_facet Facelli, J.C.
Orendt, A.M.
Contreras, R.H.
Tufró, M.F.
De Kowalewski, D.G.
author_sort Facelli, J.C.
title Ab initio and 17O NMR studies of the substituent effects on the tautomeric equilibrium in 6-X-1H-2-pyridones
title_short Ab initio and 17O NMR studies of the substituent effects on the tautomeric equilibrium in 6-X-1H-2-pyridones
title_full Ab initio and 17O NMR studies of the substituent effects on the tautomeric equilibrium in 6-X-1H-2-pyridones
title_fullStr Ab initio and 17O NMR studies of the substituent effects on the tautomeric equilibrium in 6-X-1H-2-pyridones
title_full_unstemmed Ab initio and 17O NMR studies of the substituent effects on the tautomeric equilibrium in 6-X-1H-2-pyridones
title_sort ab initio and 17o nmr studies of the substituent effects on the tautomeric equilibrium in 6-x-1h-2-pyridones
publishDate 1992
url http://hdl.handle.net/20.500.12110/paper_00223654_v96_n20_p7895_Facelli
https://repositoriouba.sisbi.uba.ar/gsdl/cgi-bin/library.cgi?a=d&c=artiaex&d=paper_00223654_v96_n20_p7895_Facelli_oai
work_keys_str_mv AT facellijc abinitioand17onmrstudiesofthesubstituenteffectsonthetautomericequilibriumin6x1h2pyridones
AT orendtam abinitioand17onmrstudiesofthesubstituenteffectsonthetautomericequilibriumin6x1h2pyridones
AT contrerasrh abinitioand17onmrstudiesofthesubstituenteffectsonthetautomericequilibriumin6x1h2pyridones
AT tufromf abinitioand17onmrstudiesofthesubstituenteffectsonthetautomericequilibriumin6x1h2pyridones
AT dekowalewskidg abinitioand17onmrstudiesofthesubstituenteffectsonthetautomericequilibriumin6x1h2pyridones
_version_ 1809357075482935296