Torsion angle relationship of the 17O NMR chemical shift in α,β-unsaturated carbonyl compounds

✍ Scribed by Francesca Mocci

• Publisher: John Wiley and Sons
• Year: 2009
• Tongue: English
• Weight: 212 KB
• Volume: 47
• Category: Article
• ISSN: 0749-1581
• DOI: 10.1002/mrc.2488

✦ Synopsis

Abstract

The torsion angle effect on the isotropic shielding of ^17^O nucleus in α,β‐unsaturated carbonyl groups is studied by means of density functional theory (DFT) calculations using a polarizable continuum model (PCM) for the solvent, employing the PBE0 functional together with the 6‐311G(d,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 α‐diketones. Copyright © 2009 John Wiley & Sons, Ltd.