ISSN:
0749-1581
Keywords:
Chemistry
;
Analytical Chemistry and Spectroscopy
Source:
Wiley InterScience Backfile Collection 1832-2000
Topics:
Chemistry and Pharmacology
Notes:
The 13C NMR spectra of 7-, 8-, 9- and 10-fluoro-benzo[a]pyrenes have been recorded and the chemical shifts of all protonated (and fluorine-substituted) carbons have been assigned. The effect of fluorine on carbon shifts (and also on electron densities, which correlate reasonably well with the shifts) is confined largely to the fluorinated ring and contiguous sites, such as peri positions or carbons across bay regions. A variety of short- and long-range couplings are observed, and correlations with π-bond orders (two-bond couplings) and ato n polarizabilities (one-bond couplings) are observed. Long-range coupling patterns are less obvious, but six-bond couplings appear to correlate with atom-atom polarizabilities, as expected for transfer of spin information through the π-system.
Additional Material:
7 Tab.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1002/mrc.1260240404
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