Chemical shifts and coupling constants are reported for seven azole derivatives (iidamles, triazoles and their b e m derivatives), their quaternary salts and the corresponding dicyanomethylides. The assignment of the heterocyclic carbons is based on couplings with the N-methyl group. Compared with n
Studies in sulphur heterocyles. 2—The 13C NMR spectra of thienocoumarins
✍ Scribed by Norman M. D. Brown; Asish De; John S. A. Brunskill; Howard Jeffrey
- Publisher
- John Wiley and Sons
- Year
- 1982
- Tongue
- English
- Weight
- 281 KB
- Volume
- 18
- Category
- Article
- ISSN
- 0749-1581
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✦ Synopsis
Abstract
^13^C NMR spectra of 3‐ substituted thieno[2,3‐h][1]benzopyran‐2‐ones and 8‐substituted thieno[3,2‐f]‐[1]benzopyran‐7‐ones are reported and the substituent dependence of certain ^13^C chemical shifts is noted.
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