The effect of self-association on the carbonyl carbon NMR screening constant is determined for 15 ketones. It is shown that the corresponding screening constant term can only be related to the dipole moment and the molecular volume both for aliphatic and alicyclic ketones. The average distance betwe
Résonance Magnétique Nucléaire de 17O. Aldéhydes et cétones aliphatiques: additivité des effets de substitution et corrélation avec la 13C-RMN
✍ Scribed by Claude Delseth; Jean-Pierre Kintzinger
- Publisher
- John Wiley and Sons
- Year
- 1976
- Tongue
- German
- Weight
- 595 KB
- Volume
- 59
- Category
- Article
- ISSN
- 0018-019X
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✦ Synopsis
^17^O‐NMR. Aliphatic aldehydes and ketones, additivity of substituent effects and correlation with ^13^C‐NMR.
The ^17^O‐chemical shifts of 9 aldehydes, 22 aliphatic and 4 alicyclic ketones, in the natural abundance FT.‐NMR. spectra followed a good correlation with the ^13^C‐chemical shifts of the terminal C‐atoms of corresponding methylene compounds. An additivity relation involving 6 parameters represents the ^17^O‐shifts of 28 of the measured products with a standard deviation of 2.5 ppm. The additivity parameters are discussed with respect to the modifications of the polarity of the carbonyl group induced by the hyperconjugative interaction of π and π* orbitals with the πCH~3~ orbitals of the alkyl substituent groups.
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