ISSN:
0030-4921
Keywords:
Chemistry
;
Analytical Chemistry and Spectroscopy
Source:
Wiley InterScience Backfile Collection 1832-2000
Topics:
Chemistry and Pharmacology
Notes:
Analyses of the 1H NMR spectra of fluorene, 2-nitrofluorene, 1-azafluorene, 2-azafluorene, 4-azafluorene, 7-nitro-4-azafluorene and 1,4-diazafuorene have been carried out using computer calculations and homo double resonance techniques. The relative signs and magnitude of the 4J, 5J and 6J long-range coupling constants of the 9-CH2 group protons with the pyridine and phenylene ring protons have been measured by five- and six-spin calculations. It was established that the presence of substituents and the N heteroatom has only a very weak effect on the values and signs of these coupling constants. The usual alternating signs of long-range coupling constants involving π-electron systems were confirmed, giving negative signs for even and positive signs for odd numbers of bonds separating the coupling protons.
Additional Material:
3 Ill.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1002/omr.1270210505
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