Carbon-13 Nuclear Magnetic Resonance Spectroscopy : Conformational Analysis of Methyl-Substituted Cycloheptanes, Cycloheptanols, and Cycloheptanones
Please always quote using this URN: urn:nbn:de:bvb:20-opus-41663
- The 130 chemical shifts were determined of the carbons in 12 cycloheptanes, 21 cycloheptanols, and 8 cycloheptanones. In some cyc1oheptanols and cyc1oheptanones, the assignments have been obtained unambiguously by the synthesis of deuterated derivatives and the use of paramagnetic-shift reagents. Substituent effects for the different types of groups have been calculated. The most informative data about the cyc10heptane conformations were provided by the relatively well understood I' effects. The results are generally in,good agreement withThe 130 chemical shifts were determined of the carbons in 12 cycloheptanes, 21 cycloheptanols, and 8 cycloheptanones. In some cyc1oheptanols and cyc1oheptanones, the assignments have been obtained unambiguously by the synthesis of deuterated derivatives and the use of paramagnetic-shift reagents. Substituent effects for the different types of groups have been calculated. The most informative data about the cyc10heptane conformations were provided by the relatively well understood I' effects. The results are generally in,good agreement with predictions based on the twist-chair form, which has been predicted by Hendrickson to be the most stable conformation. Pairs of cis-trans isomers are found to have rather characteristic differences in their 130 spectra. This fact was used to assign the resonances found for cis-trans mixtures of methyl-substituted cyc1oheptanols to specific isomers.…
Author: | Manfred Christl, John D. Roberts |
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URN: | urn:nbn:de:bvb:20-opus-41663 |
Document Type: | Journal article |
Faculties: | Fakultät für Chemie und Pharmazie / Institut für Organische Chemie |
Language: | English |
Year of Completion: | 1972 |
Source: | In: Journal of Organic Chemistry, 1972, 37, 22, 3443 - 3452 |
Dewey Decimal Classification: | 5 Naturwissenschaften und Mathematik / 54 Chemie / 540 Chemie und zugeordnete Wissenschaften |
Release Date: | 2010/04/11 |