The conformational properties of six thio derivatives of benzocycloheptene were studied by 1H and 13C high-field NMR spectroscopy in solution at low temperature. Both parent compounds 2 and 6, with sulfur at positions 3 and 1, respectively, were found to exist in the chair conformation. The 2-substituted derivatives of 2 (3: Y= OCH3 and 4: Y= Cl) revealed the presence of the Ca form only. In contrast, the 2-substituted derivatives of 6 (7: Y= ...
