Stereochemistry of seven-membered heterocycles 11. Isoenergy chair-twist conformation equilibrium in phthalylformal and its 2-phenyl derivative

Abstract

By means of dynamic13C NMR, spectra have been obtained for the "frozen" chair and twist conformers of phthalylformal and its 2-phenyl derivative. The γ-effects of the phenyl substituent have been analyzed for both conformational species. 2. The introduction of a phenyl group into position 2 of phthalylformal is not reflected in the magnitude of the conformational free energy. © 1983 Plenum Publishing Corporation