Migratory cycloisomerization of 1,3-dien-5-ynes conjugated with pseudopeptides in assembly of benzo[7]annulenes†
Abstract
A novel domino cycloisomerization of 1,3-dien-5-ynes for the synthesis of 7H-benzo[7]annulenes is reported. The noticeable feature of this domino reaction involves the assembly of the fused bicyclic motifs through a transamidation/5-exo-trig cyclization/8π-electrocyclization sequence in a single step. Finally, mechanistic investigations were conducted experimentally and supported by DFT calculations.