## Abstract The signs of the spin–spin coupling constants between the aldehydic proton and the fluorine nuclei in pentafluorobenzaldehyde are negative over four and six formal bonds and positive over five bonds. The opposite signs had been assumed in previous studies of this molecule. The correct s
14N, 1H spin couplings in diethylmethylvinylammonium bromide
✍ Scribed by Masako Ueyama (nee Ohtsuru); Kazuo Tori
- Publisher
- John Wiley and Sons
- Year
- 1972
- Tongue
- English
- Weight
- 274 KB
- Volume
- 4
- Category
- Article
- ISSN
- 0749-1581
No coin nor oath required. For personal study only.
✦ Synopsis
Abstract
The proton magnetic resonance spectrum of diethylmethylvinylammonium bromide, in which splittings due to ^14^N, ^1^H spin couplings are clearly observed as strongly perturbed second‐order patterns, has been analysed and the difference in the substituent effect between a methyl and an ethyl group upon ^1^H, ^1^H and ^14^N, ^1^H spin couplings are summarised.
📜 SIMILAR VOLUMES
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Predictive quantum chemical methods based upon coupled cluster theory of spin-spin coupling constants offer a direct tool to explore a variety of questions concerning the relationship between coupling constants and intermolecular distances, molecular orientation, changes in hybridization and related
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## Abstract ^15^N‐enriched dihydroxamic acids (HONHCO(CH~2~)~__n__~CONHOH, __n__ = 0, 1, and 2) were prepared and their spectra NMR (^1^H, ^13^C, ^15^N) recorded in dimethyl sulfoxide (DMSO) solutions with the aim of determining ^15^N coupling constants (^15^N^1^H and ^15^N^13^C). The results sup
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