Polyene Cyclization Promoted by the Cross-Conjugated alpha-Carbalkoxy Cyclohexenone System. An Unusual 1,2-Hydride Shift under Lewis Acid Catalysis

摘要

Polyene cyclization of the titled compounds under catalysis with AlCl3/SnCl4 gave rise to the corresponding polycyclic products, many of which were structurally highly unexpected, and thus, individual X-ray analysis was required to finalize the structural identification. Mechanistically, an unusual 1,2-hydride shift is proposed to elucidate the product formation.