Saturated amine oxides : part 10. hydroacridines: part 32. linear ¹⁷O/¹³C and ¹³C/¹³C chemical shift correlations between saturated azaheterocyclic N-methylamine N-oxides, and the methiodides of their parent amines
Copyright © 2015 John Wiley & Sons, Ltd.
Veröffentlicht in: | Magnetic resonance in chemistry : MRC. - 1985. - 53(2015), 10 vom: 21. Okt., Seite 845-8 |
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1. Verfasser: | |
Format: | Online-Aufsatz |
Sprache: | English |
Veröffentlicht: |
2015
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Zugriff auf das übergeordnete Werk: | Magnetic resonance in chemistry : MRC |
Schlagworte: | Journal Article 13C NMR 17O NMR NMR linear correlations piperidines quaternary ammonium salts saturated amine oxides tetradecahydroacridines tropane alkaloids |
Zusammenfassung: | Copyright © 2015 John Wiley & Sons, Ltd. Two kinds of good linear correlations were found between the chemical shifts of saturated six-membered azaheterocyclic N-methylamine N-oxides and the chemical shifts of the methiodides of their parent amines. One of the correlations occurs between the (17)O chemical shift of the N(+)-O(-) oxygen in the N-oxides and the (13)C chemical shift of the N(+)-CH3 methyl group analogously situated in the appropriate methiodide (r = 0.9778). This correlation enables unambiguous configuration assignment of the N(+)-O(-) bond, even if the experimentally observed (17)O chemical shift of only one N-epimer is available, provided the (13)C chemical shifts of both N(+)-CH3 groups in the methiodide are known and assigned; furthermore, it can be used also for the estimation of (17)O chemical shifts of the N(+)-O(-) oxygens in N-epimeric pairs of N-oxides, for which observed (17)O data hardly become available. The second correlation is observed between the (13)C chemical shift of the N(+)-CH3 methyl group in the N-oxides and the (13)C chemical shift of the N(+)-CH3 methyl group analogously situated in the appropriate methiodide (r = 0.9785). It can be used for safe configuration assignment of the N(+)-CH3 group and, indirectly, also of the N(+)-O(-) bond in an amine N-oxide, even if no (17)O NMR data, and the (13)C chemical shift of only one N-epimer is available |
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Beschreibung: | Date Completed 14.12.2015 Date Revised 19.09.2015 published: Print-Electronic Citation Status PubMed-not-MEDLINE |
ISSN: | 1097-458X |
DOI: | 10.1002/mrc.4286 |