Studies of substituent effects by carbon-13 NMR spectroscopy. Thiophene and furan chalcone analogues
✍ Scribed by Giuseppe Musumarra; Francesco P. Ballistreri
- Publisher
- John Wiley and Sons
- Year
- 1980
- Tongue
- English
- Weight
- 686 KB
- Volume
- 14
- Category
- Article
- ISSN
- 0749-1581
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✦ Synopsis
Abstract
^13^C NMR spectra of 39 thiophene and furan chalcone analogues in CDCl~3~ solutions are reported. The effect of substituents on the ^13^C chemical shifts in the phenyl and in the 5‐membered rings is discussed. ^13^C NMR shifts are correlated with Hammett parameters and with experimental shifts in the chalcone series.
📜 SIMILAR VOLUMES
## Abstract ^13^C NMR shifts of 54 chalcones and their thiophene and furan analogues are analyzed by principal component analysis. Thus, a mathematical model is derived for the variation of the carbon shifts in each of seven classes. Two component models are found to be adequate by cross‐validation
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## Abstract ^13^C NMR chemical shifts are reported for several alkyl or aryl amines, acetamides, diacetamides and ammonium and trimethylammonium salts. Substituent effects, determined with respect to chemical shifts of amino derivatives, are rationalized in terms of γ effects, steric interactions a
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