Navegar

Colección

Datos Estadísticas

Artículo

La versión final de este artículo es de uso interno. El editor solo permite incluir en el repositorio el artículo en su versión post-print. Por favor, si usted la posee enviela a
Consulte el artículo en la página del editor
Consulte la política de Acceso Abierto del editor

Abstract:

The deshielding effect produced by repulsive interactions between proximate groups was studied from a theoretical point of view, calculating the magnetic shielding constants for the following nuclei: 17O in di-coordinated and carbonyl oxygen atoms; 19F and 13C. The "super molecule" approach was used to study the proximity effect in the following three model systems: water-methane; formaldehyde-methane; methyl fluoride-methane, calculating the chemical shieldings for various intermolecular distances. Calculations were carried out using the giao approach with an ab initio ground state wavefunction calculated with the 6-31G** basis set. Linear correlations are found between the intermolecular effects on the magnetic shielding constants and the interaction energies, yielding an increase in the deshielding effect when increasing the repulsion between the two molecules. © 1993.

Registro:

Documento: Artículo
Título:Proximity effects on the nuclear magnetic shielding tensor. Part 1. An ab initio study of 17O and 19F chemical shifts in the proximity of a methyl group
Autor:Facelli, J.C.; Contreras, R.H.; Tufró, M.F.
Filiación:Department of Chemistry, Utah Supercomputing Institute, The University of Utah, Salt Lake City, UT 84112, United States
Departamento de Fisca, FCEyN, Universidad de Buenos Aires, Pabellon I Ciudad Universitaria, 1428 Buenos Aires, Argentina
Año:1993
Volumen:281
Número:1
Página de inicio:61
Página de fin:66
DOI: http://dx.doi.org/10.1016/0166-1280(93)80029-Y
Título revista:Journal of Molecular Structure: THEOCHEM
Título revista abreviado:J. Mol. Struct. THEOCHEM
ISSN:01661280
CODEN:THEOD
Registro:https://bibliotecadigital.exactas.uba.ar/collection/paper/document/paper_01661280_v281_n1_p61_Facelli

Referencias:

  • Memory, (1968) Quantum Theory of Magnetic Resonance Parameters, , McGraw-Hill, New York
  • Jameson, (1991) Nuclear Magnetic Resonance, a Specialist Periodical Report, 20. , G.A. Webb, Royal Society of Chemistry, London, Chapter 2
  • Gerothanassis, (1991) Nuclear Magnetic Resonance, a Specialist Periodical Report, 20. , G.A. Webb, Royal Society of Chemistry, London, Chapter 3
  • Ferraro, Natiello, Contreras, The use of inner projections of the polarization propagator to study different contributions to the magnetic shielding tensor. I. Proton deshielding by steric compression (1986) International Journal of Quantum Chemistry, 30, p. 77
  • Ferraro, de Kowalewski, Contreras, Ortiz, (1987) Chem. Phys., 118, p. 325
  • Gribble, Keavy, Olson, Rae, Staffa, Herr, Ferraro, Contreras, Fluorine deshielding in the proximity of a methyl group. An experimental and theoretical study (1991) Magnetic Resonance in Chemistry, 29, p. 422
  • Li, Chesnut, Intramolecular van der waals interactions and chemical shifts: A model for β- and γ-effects (1985) Magnetic Resonance in Chemistry, 23, p. 625
  • Li, Chesnut, Intramolecular van der Waals interactions and13C chemical shifts: Substituent effects in some cyclic and bicyclic systems (1986) Magnetic Resonance in Chemistry, 24, p. 93
  • Grover, Gthrie, Stothers, Tan, (1977) J. Magn. Reson., 10, p. 227
  • Eliel, Liu, Chandrasekaran, 17O NMR spectra of equatorial and axial hydroxycyclohexanes and 5-hydroxy-1,3-dioxanes and their methyl ethers (1983) Organic Magnetic Resonance, 21, p. 179
  • Baumstark, Balakrishnan, Dotrong, McCIoskey, Oakley, Boykin, (1987) J. Am. Chem. Soc., 109, p. 1059
  • Boykin, Hertzler, Delphon, Eisenbraun, (1989) J. Org. Chem., 54, p. 1418
  • Boykin, Dewprashad, Eisenbraun, (1990) J. Org. Chem., 55, p. 425
  • Boykin, Baumstark, (1989) Tetrahedron, 45, p. 3613
  • Boykin, Baumstark, Kayser, Soucy, 17O nuclear magnetic resonance spectroscopic study of substituted phthalic anhydrides and phthalides (1987) Canadian Journal of Chemistry, 65, p. 1214
  • Baumstark, Dotrong, Oakley, Stark, Boykin, (1987) J. Org. Chem., 52, p. 3640
  • Baumstark, Dotrong, Stark, Boykin, (1988) Tetrahedron Lett., p. 2143
  • Wolinski, Hinton, Pulay, (1990) J. Am. Chem. Soc., 112, p. 8251
  • Pople, Beveridge, (1970) Approximate Molecular Orbital Theory, , McGraw-Hill, New York
  • Clementi, Corongiu, Chakravorty, (1990) MOTECC, Modern Techniques in Computational Chemistry, , E. Clementi, ESCON, Leiden
  • Allinger, (1977) J. Am. Chem. Soc., 99, p. 8127
  • Boykin, (1991) 17-O NMR Spectroscopy in Organic Chemistry, , CRC Press, Boca Raton, FL
  • Contreras, Biekofsky, de Kowalewski, Orendt, Facelli, (1993) J. Phys. Chem., 97, p. 91
  • Biekofsky, Pomilio, Contreras, de Kowalewski, Facelli, Experimental and theoretical study of the methoxy group conformational effect on13C chemical shifts inortho-substituted anisoles (1989) Magnetic Resonance in Chemistry, 27, p. 158

Citas:

---------- APA ----------
Facelli, J.C., Contreras, R.H. & Tufró, M.F. (1993) . Proximity effects on the nuclear magnetic shielding tensor. Part 1. An ab initio study of 17O and 19F chemical shifts in the proximity of a methyl group. Journal of Molecular Structure: THEOCHEM, 281(1), 61-66.
http://dx.doi.org/10.1016/0166-1280(93)80029-Y
---------- CHICAGO ----------
Facelli, J.C., Contreras, R.H., Tufró, M.F. "Proximity effects on the nuclear magnetic shielding tensor. Part 1. An ab initio study of 17O and 19F chemical shifts in the proximity of a methyl group" . Journal of Molecular Structure: THEOCHEM 281, no. 1 (1993) : 61-66.
http://dx.doi.org/10.1016/0166-1280(93)80029-Y
---------- MLA ----------
Facelli, J.C., Contreras, R.H., Tufró, M.F. "Proximity effects on the nuclear magnetic shielding tensor. Part 1. An ab initio study of 17O and 19F chemical shifts in the proximity of a methyl group" . Journal of Molecular Structure: THEOCHEM, vol. 281, no. 1, 1993, pp. 61-66.
http://dx.doi.org/10.1016/0166-1280(93)80029-Y
---------- VANCOUVER ----------
Facelli, J.C., Contreras, R.H., Tufró, M.F. Proximity effects on the nuclear magnetic shielding tensor. Part 1. An ab initio study of 17O and 19F chemical shifts in the proximity of a methyl group. J. Mol. Struct. THEOCHEM. 1993;281(1):61-66.
http://dx.doi.org/10.1016/0166-1280(93)80029-Y