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13C chemical shifts and conformational analysis of methyl substituted thiacyclopentanes

✍ Scribed by G. Barbarella; P. Dembech

Publisher: John Wiley and Sons
Year: 1980
Tongue: English
Weight: 530 KB
Volume: 13
Category: Article
ISSN: 0749-1581
DOI: 10.1002/mrc.1270130414

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✦ Synopsis

Abstract

The ^13^C NMR spectra of thiacyclopentane (thiolane) and its mono‐ and dimethyl derivatives at positions other than the heteroatom are reported. The ^13^C shieldings are found to be consistent with a description of these compounds in terms of equilibria between half‐chair conformers. An attempt has been made to establish the axial or equatorial preference of methyl groups adjacent to, or removed from, the sulphur atom in these systems. In agreement with previous observations on thiacyclohexanes (thianes), the conformational preference of a methyl group for the equatorial orientation is greater at the β than at the α position.

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