Dynamic NMR study of the electronic state of heteroaromatics. IX—π-Electron deficiency of various substituted thiazinethiones, thiazinium salts and analogous pyrimidines by means of barriers to rotation about exocyclic partial C,N double bonds
| العنوان: | Dynamic NMR study of the electronic state of heteroaromatics. IX—π-Electron deficiency of various substituted thiazinethiones, thiazinium salts and analogous pyrimidines by means of barriers to rotation about exocyclic partial C,N double bonds |
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| المؤلفون: | Werner Schroth, Kalevi Pihlaja, Erich Kleinpeter |
| المصدر: | Magnetic Resonance in Chemistry. 29:223-230 |
| بيانات النشر: | Wiley, 1991. |
| سنة النشر: | 1991 |
| مصطلحات موضوعية: | chemistry.chemical_classification, Steric effects, Double bond, Stereochemistry, Chemical shift, Substituent, General Chemistry, Nuclear magnetic resonance spectroscopy, Electron deficiency, Spectral line, chemistry.chemical_compound, Crystallography, chemistry, Proton NMR, General Materials Science |
| الوصف: | The 1H NMR spectra and the barriers to rotation about exocyclic partial C,N double bonds of various series of thiazinethiones 1, the corresponding thiazinium salts 5–9 and some pyrimidinethiones 10–13 are reported and discussed with respect to the π-electron deficiency of these heteroaromatic compounds. Substituent influences are critically considered; in particular, the C,N barrier differences of C,NMe2 and C, pyrrolidino were used to estimate the type of dynamic process, which is different in pyrimidinethiones 10–13 and thiazinethiones/thiazinium salts 1–9. The compounds studied corroborate the pseudo-chalcogeno analogy principle. Previously studied compounds are included to display the π-electron deficiency influence of the heterocyclic system on the 1H chemical shifts of NR2, phenyl, the H-5 protons and the exocyclic barriers to C,N rotation; adequate quantitative estimations are reported. |
| تدمد: | 1097-458X 0749-1581 |
| الوصول الحر: | https://explore.openaire.eu/search/publication?articleId=doi_________::569680a8b1accf1e46bda7d355b5a7b2Test https://doi.org/10.1002/mrc.1260290306Test |
| حقوق: | CLOSED |
| رقم الانضمام: | edsair.doi...........569680a8b1accf1e46bda7d355b5a7b2 |
| قاعدة البيانات: | OpenAIRE |
| تدمد: | 1097458X 07491581 |
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