## 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
1H NMR analysis of the methoxy group conformation in methoxychromones
✍ Scribed by Katalim E. Kövér; J. Borbély
- Publisher
- John Wiley and Sons
- Year
- 1985
- Tongue
- English
- Weight
- 367 KB
- Volume
- 23
- Category
- Article
- ISSN
- 0749-1581
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✦ Synopsis
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. NOE data were used in the calculations of conforrmer population ratios in these six‐spin (ABCX~3~) systems.
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