Artículos de revistas
1hJFH coupling in 2-fluorophenol revisited: Is intramolecular hydrogen bond responsible for this long-range coupling?
Fecha
2011-11Registro en:
Cormanich, Rodrigo A.; Moreira, Marilua A.; Freitas, Matheus P.; Ramalho, Teodorico C.; Anconi, Cléber P. A.; et al.; 1hJFH coupling in 2-fluorophenol revisited: Is intramolecular hydrogen bond responsible for this long-range coupling?; John Wiley & Sons Ltd; Magnetic Resonance in Chemistry; 49; 12; 11-2011; 763-767
0749-1581
CONICET Digital
CONICET
Autor
Cormanich, Rodrigo A.
Moreira, Marilua A.
Freitas, Matheus P.
Ramalho, Teodorico C.
Anconi, Cléber P. A.
Rittner, Roberto
Contreras, Ruben Horacio
Tormena, Cláudio F.
Resumen
The present study shows that a hydrogen bond between the OH group and the fluorine atom is not involved in the 1hJFH spin-spin coupling transmission either for 4-bromo-2-fluorophenol or 2-fluorophenol. In fact, according to a quantum theory of atoms in molecules analysis, no bond critical point is found between O-H and F moieties. The nature of the transmission mechanism of the Fermi contact term of the 1hJ FH spin-spin coupling is studied by analyzing canonical molecular orbitals (see J. Phys. Chem. A 2010, 114, 1044), and it is observed that virtual orbitals play only a quite minor role in its transmission. This is typical of a Fermi contact term transmitted mainly through exchange interactions owing to the overlap of proximate electronic clouds; therefore, it is suggested to identify them as nTSJFH coupling where n stands for the number of formal bonds separating the coupling nuclei. In the cases studied in this work is n = 4. Results presented in this work could provide an interesting rationalization for different experimental signs known in the current literature for proximate JFH couplings. © 2011 John Wiley & Sons, Ltd.