Indirect nuclear Overhauser enhancements through 19F have been determined for the three-spin systems 'H-I9F-'H and 1H-'9F-'3C by steady-state presaturation of the appropriate proton, and applied to the conformational analysis of 5-bromo-2-fluoro-4-nitroacetanilide. The 'H NOE difference spectra at 4
Application of selective 13C{1H} nuclear overhauser effects with low-power 1H irradiation in carbon-13 NMR spectroscopy
✍ Scribed by Jun Uzawa; Setsuo Takeuchi
- Publisher
- John Wiley and Sons
- Year
- 1978
- Tongue
- English
- Weight
- 335 KB
- Volume
- 11
- Category
- Article
- ISSN
- 0749-1581
No coin nor oath required. For personal study only.
✦ Synopsis
Abstract
The feasibility of the application of selective ^13^C{^1^H} nuclear Overhauser effect (NOE) measurements to organic structural analysis in ^13^C NMR spectroscopy has been investigated at 25 MHz using citraconic anhydride and the methyl ester of pentalenolactone as model compounds. This selective ^13^C{^1^H} NOE technique with single frequency low‐power ^1^H irradiation should find wide application in the structural elucidation of organic compounds, especially for the reliable assignment of quaternary carbon signals.
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