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17O NMR spectra and conformation of cyclic vinyl ethers

✍ Scribed by Esko Taskinen; Mikko Ora

Publisher: John Wiley and Sons
Year: 1995
Tongue: English
Weight: 432 KB
Volume: 33
Category: Article
ISSN: 0749-1581
DOI: 10.1002/mrc.1260330402

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✦ Synopsis

The "0 NMR spectra of a number of heterocyclic vinyl ethers were recorded in CDCI, and DMSO-d, solutions. The oxygen chemical shifts reveal substantial differences in the strength of p-n conjugation between the five-and six-membered ring compounds, especially between those with an exocyclic C=C bond. The conformations of the title compounds were estimated by force-field calculations; the calculated torsional angle of the C-0-C-pC moiety appears to be a linear function of the "0 NMR shift data, corrected by appropriate structural factors.

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