torsion angle effect on the isotropic shielding of (17)O nucleus in alpha,beta-unsaturated carbonyl groups is studied by means of density functional theory (DFT) calculations using a polarizable continuum model (PCM) for the solvent, employing the PBEO functional together with the 6-311 G(cl,p) basis set for geometry optimization, and the 6-311+G(2d,p) basis set for calculating the NMR shielding with the gauge-including atomic orbitals (GIAO) method. This study adds new information on the sensitivity of the (17)O nucleus to conformational changes, revealing a strong dependence of the (17)O NMR chemical shift on the dihedral angle between the carbonyl and the vinyl moiety in all studied compounds; remarkable differences are observed with the data reported for alpha-diketones. Copyright (C) 2009 John Wiley & Sons, Ltd.
Torsion angle relationship of the (17)O NMR chemical shift in alpha,beta-unsaturated carbonyl compounds
MOCCI, FRANCESCA
2009-01-01
Abstract
torsion angle effect on the isotropic shielding of (17)O nucleus in alpha,beta-unsaturated carbonyl groups is studied by means of density functional theory (DFT) calculations using a polarizable continuum model (PCM) for the solvent, employing the PBEO functional together with the 6-311 G(cl,p) basis set for geometry optimization, and the 6-311+G(2d,p) basis set for calculating the NMR shielding with the gauge-including atomic orbitals (GIAO) method. This study adds new information on the sensitivity of the (17)O nucleus to conformational changes, revealing a strong dependence of the (17)O NMR chemical shift on the dihedral angle between the carbonyl and the vinyl moiety in all studied compounds; remarkable differences are observed with the data reported for alpha-diketones. Copyright (C) 2009 John Wiley & Sons, Ltd.
I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
