1H and13C NMR study of the effects exerted by an oxirane ring in the epoxybicyclo-[2.2.2]octane series
作者:H. Christol、C. Laffite、F. Plénat、G. Renard
DOI:10.1002/mrc.1270170207
日期:1981.10
AbstractThe 1H and 13C NMR spectra of 2,3‐disubstituted exo‐5,6‐ and endo‐5,6‐bicyclo[2.2.2]octanes, and the corresponding alkanes, have been investigated to determine the effects exerted by an oxirane ring. The 1H NMR study showed that the anti protons, H‐7a and H‐8a, are significantly shielded and the syn protons, H‐7s and H‐8s, are deshielded, although to a smaller extent, by the exo‐oxirane. An endo‐oxirane has practically no effect on the same protons. The stereochemistry of epoxybicyclo[2.2.2]octanes is, thus, easily deduced from 1H NMR data. The 13C NMR study of the epoxy compounds provided an estimate of the value of α, β, γ syn and γ anti effects (to the epoxide oxygen) of an oxirane ring. In these rigid bicyclic molecules, of known geometry, the γ syn and the γ anti effects are of the same value, even though the dihedral angles are very different (0° and 120°).
Gastel, F. J. C. van; Klunder, A. J. H.; Zwanenburg, B., Recueil des Travaux Chimiques des Pays-Bas, 1991, vol. 110, # 5, p. 175 - 184
作者:Gastel, F. J. C. van、Klunder, A. J. H.、Zwanenburg, B.
DOI:——
日期:——
Plenat, Francoise; Renard, Gilbert; Christol, Henri, Bulletin de la Societe Chimique de France, 1980, vol. 2, # 3-4, p. 125 - 132
作者:Plenat, Francoise、Renard, Gilbert、Christol, Henri