Highly stereoselective and efficient synthesis of functionalized cyclohexanes with multiple stereocenters

Chiral 7-oxo-2-enimides 2, which were readily obtained through a silyloxy-Cope rearrangement of syn-aldol products 1, have proved to be versatile substrates for a one-step, highly efficient and stereoselective synthesis of functionalized cyclohexanes. Organocopper and organoaluminum reagents have been employed as nucleophiles that underwent a conjugate addition to the enimide structure of the Cope products. The enolates formed in situ attacked the aldehyde or iminium ion in an intramolecular aldol or Mannich reaction, respectively, to directly yield cyclohexanols 3 and 4 and cyclohexylamines 5, respectively, in moderate to good yields and with excellent stereocontrol.