We have recently disclosed a palladium-catalyzed Trost–Oppolzer type Alder-ene reaction of 2,4-pentadienyl acetates for the synthesis of highly substituted cyclopentadienes and cyclopentene-fused aromatics. The overall transformation also represents an acid-free iso-Nazarov type cyclization. Herein, we provide the hypothesis and rationale behind this work, while highlighting the seminal contributions of Trost, Oppolzer and others towards the development of the palladium-ene reaction.
Key words
Tsuji–Trost reaction - metallo-ene reaction - iso-Nazarov reaction - natural products - annulation - cyclopentanes