## Abstract The methoxy group conformation of chromone derivatives was studied by ^1^H NMR methods. For the qualitative determination of the conformational preferences of the model compounds, proton relaxation rates, spin‐spin decoupling difference spectroscopy and 2D COSY experiments were applied.
A proton NMR analysis of the OCH3 group conformation in 2-methoxypyridines
✍ Scribed by R. H. Contreras; J. C. Facelli; D. G. de Kowalewski
- Publisher
- John Wiley and Sons
- Year
- 1982
- Tongue
- English
- Weight
- 226 KB
- Volume
- 20
- Category
- Article
- ISSN
- 0749-1581
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✦ Synopsis
Abstract
The absence of HH couplings between the methoxy group and the ring protons observed in 2‐methoxy‐, 2,6‐dimethoxy‐ and 2‐methoxy‐6‐chloropyridines is interpreted in terms of a cis conformation between the methyl fragment and the nitrogen ring atom. Other data, taken from the current literature, support this conclusion.
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