Theoretical Studies on Pentadienyl Cation Electrocyclizations

Pentadienyl cation electrocyclizations have played key roles in the syntheses of many complex organic molecules. Herein, theoretical studies on the mechanisms of pentadienyl cation electrocyclizations are reviewed and general principles applicable to the design of such reactions are highlighted. Keywords: Pentadienyl, carbocation, electrocyclization, Nazarov, quantum chemistry, Cyclopentene rings, Post-Hartree-Fock, Density functional theory, Highest occupied molecular orbital (HOMO), Conrotation, Torquoselectivity, C2 rotation, Houk's torquoselectivity model, Lewis acid activation, Trauner's systems, Vinyl allenes, Hammond Postulate, The Bell-Evans-Polanyi Principle, Zwitterionic species, Piancatelli reaction, Substituents at C3, Brønsted acids, Metal Promoted Cyclizations