NMR‐Untersuchungen an Dicyclopentadien‐Derivaten. VII. Zur Abhängigkeit des γ‐gauche Effektes von der sterischen Kompression eng benachbarter Protonen bei exo/endo‐Isomerieumkehr

N.M.R. Investigations of Dicyclopentadiene Derivatives. VII. Dependence of the γ‐Gauche Effect on the Steric Compression of Closely Neighbouring Protons during the Reversal of Exo/Endo‐Isomerism The 13C‐chemical shifts of the carbon atoms C1, C6, C7, C8 and C10 of different substituted exo/endo‐isomeric dicyclopentadiene derivatives are highly depending on the configuration of these compounds. The observed shift effects are discussed within the concept of the steric γ‐gauche effect and are not only explained by nonbonding interactions of steric closely neighbouring protons.