M R shielding measurements reveal that thiolo-imidazole and -tetrazole exist almost entirely as the thione form. Quantitative estimates of the position of tautomerism in 1,2,3-triazole and tetrazole are obtained. The reported assignments are supported by means of INDO/S-SOS shielding calculations.
Application of 15N NMR to a quantitative investigation of tautomerism in some thiolopyridines
✍ Scribed by L. Stefaniak; G. A. Webb; C. Brevard; M. Bourdonneau; R. Lejeune; L. Thunus; C. L. Lapière
- Publisher
- John Wiley and Sons
- Year
- 1985
- Tongue
- English
- Weight
- 181 KB
- Volume
- 23
- Category
- Article
- ISSN
- 0749-1581
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✦ Synopsis
N NMR Shielding measurements are reported for a series of derivatives of some thiolopyridines. The results obtained are used to provide quantitatively reliable estimates of three tautomeric equilibria involving the pyridine nitrogen atom.
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