Visualization of through space NMR shieldings of aromatic and anti-aromatic molecules and a simple means to compare and estimate aromaticity
- Through space NMR shieldings of aromatic (benzene, mono-substituted and annelated benzenes, ferrocene, [14]- and [18]-annulenes, phenylenes and tetra- to heptahelicene) and anti-aromatic molecules (cyclobutadiene and pentalene) were assessed by ab initio molecular-orbital calculations. Employing the nucleus-independent chemical shifts (NICS) concept, these through space NMR shieldings were visualized as iso-chemical-shielding surfaces (ICSSs) and can be applied quantitatively to determine the stereochemistry of proximal nuclei. In addition, the distances in Å at ICSS values of ±0.1 ppm in-plane and perpendicular-to-center of the aromatic ring system were employed as a simple means to compare and estimate qualitatively the aromaticity of the systems at hand.
Author details: | Erich KleinpeterORCiDGND, Sabrina Klod, Andreas KochORCiDGND |
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URL: | http://www.sciencedirect.com/science/journal/01661280 |
DOI: | https://doi.org/10.1016/j.theochem.2007.02.049 |
ISSN: | 0166-1280 |
Publication type: | Article |
Language: | English |
Year of first publication: | 2007 |
Publication year: | 2007 |
Release date: | 2017/03/25 |
Source: | Journal of molecular structure : Theochem. - ISSN 0166-1280. - 811 (2007), 1-3, S. 45 - 60 |
Organizational units: | Mathematisch-Naturwissenschaftliche Fakultät / Institut für Chemie |
Peer review: | Referiert |