The <sup>13</sup>C NMR Spectra of Some Tricyclo[2.2.0.0<sup>2,6</sup>]hexane Derivatives : Unexpected High Field Absorptions Due to Additive gamma-anti Subsituent Effects
Please always quote using this URN: urn:nbn:de:bvb:20-opus-41620
- By means of the BC NMR spectra of tricyclo{2.2.0~rfJ6Jhexane and thirteen of its derivatives the effects of substituents in endo-3- and endo-5-positions on the HC chemical shifts have been determined. The y-anti effects are at least as Jarge as in monosubstituted cyc1obutanes, where the shielding values of second-row hetero substituents exceed those in unstrained systems by far, and higher-row and carbon substituents still cause substantial upfield shifts. In the title system the y-anti effect of a substituent in the endo-3- and endo-5-positionBy means of the BC NMR spectra of tricyclo{2.2.0~rfJ6Jhexane and thirteen of its derivatives the effects of substituents in endo-3- and endo-5-positions on the HC chemical shifts have been determined. The y-anti effects are at least as Jarge as in monosubstituted cyc1obutanes, where the shielding values of second-row hetero substituents exceed those in unstrained systems by far, and higher-row and carbon substituents still cause substantial upfield shifts. In the title system the y-anti effect of a substituent in the endo-3- and endo-5-position are operative additively, and thus shift the absorption of C-J upfieJd by a maximum of 27 ppm with respect to the unsubstituted hydrocarbon.…
Author: | Manfred Christl, Hartmut Leininger, Brigitte Mattauch |
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URN: | urn:nbn:de:bvb:20-opus-41620 |
Document Type: | Journal article |
Faculties: | Fakultät für Chemie und Pharmazie / Institut für Organische Chemie |
Language: | English |
Year of Completion: | 1983 |
ISBN: | x |
Source: | In: Spectrosc. Int. J., 1983, 2, 184 - 189 |
Dewey Decimal Classification: | 5 Naturwissenschaften und Mathematik / 54 Chemie / 540 Chemie und zugeordnete Wissenschaften |
Release Date: | 2010/04/11 |
Licence (German): | Deutsches Urheberrecht |