14N and 13C NMR of tautomeric systems of mercapto- and amino-pyridines
β Scribed by Lech Stefaniak
- Publisher
- John Wiley and Sons
- Year
- 1979
- Tongue
- English
- Weight
- 289 KB
- Volume
- 12
- Category
- Article
- ISSN
- 0749-1581
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β¦ Synopsis
Abstract
Nitrogen chemical shifts are shown to provide a means of estimating equilibrium compositions of tautomeric systems of mercaptoβ and aminoβderivatives of pyridine. Carbon chemical shifts can afford only qualitative information about such equilibria.
π SIMILAR VOLUMES
Carbon, nitrogen and oxygen NMR spectra of some nitro derivatives of pyrrole and imidazole have been investigated. The 13C chemical shifts of para-carbons and the 170 chemical shifts of the nitro group correlate qualitatively with the electron densities on these carbon and oxygen atoms, which in tur
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Comparison of the "C and "N NMR spectra of 8-azatheophylline with those of its three methylated derivatives and other model compounds from the literature showed that 8-azatheophylline exists to the extent of 80% in the N-2 tautomeric form in DMSO solution.