Synthetic Approaches to Nortropanes and Nortrop-6-enes; Intramolecular Displacement by Nitrogen in 7-Membered Rings

Article abstract of DOI:10.1016/S0040-4020(01)80313-6

The synthesis of simple nortropane and nortrop-6-ene derivatives from cyclohepta-1,3-diene is described.The key intermediates are trans-1-amino-4-chloro-cycloheptanes and -cyclohept-2-enes which are derived efficiently from the corresponding cis-amino-alcohols and undergo intramolecular cyclisation.Corresponding derivatisation of cyclohexa- and cycloocta-1,3-dienes is explored and attempts to achieve Pd-catalysed cyclisation of 1-amino-4-acetoxy-derivatives is described.Nitrogen inversion data for selected nortropane derivatives are included. Key Words: nortropanes/enes; 1,4-disubstitute cyclohexanes, cycloheptanes, cyclooctanes and -enes; intramolecular cyclisation; slow nitrogen inversion.