Electrocyclization and Unexpected Reactions of Non-Stabilized α,β:γ,δ-Unsaturated Azomethine Ylides: Experimental and Theoretical Studies

Versatile, two-step syntheses of dihydrodibenzo[c,e]azepines, carbazole derivatives, and other alkaloid-type drug-like scaffolds by in situ generated azomethine ylide-induced intramolecular electrocyclization reaction from commercially available materials are presented. The reaction mechanisms of transition-metal-free carbon–carbon bond formation and the role of the kinetic control, resulting in the good regioselectivity, were confirmed by theoretical calculations.