DOI: 10.1039/A801405A

The conformation of dibenzocyclooctadiene: an experimental and theoretical NMR study

Hybrid abinitio calculations (GIAO/B3LYP/6-31G*) together with new DNMR experiments (¹H and ¹³C) have been used to clarify the problem of the conformation of 5,6,11,12-tetrahydrodibenzo[a,e]cyclooctene. The carbon-13 chemical shifts have been assigned unambiguously to the chair C and twist-boat TB conformations. Lineshape analysis of the ¹H NMR spectra has been carried out at several temperatures using an estimated set of Karplus-type vicinal coupling constants.