Trapping the π-Allylpalladium Intermediate from Fulvene-Derived Azabicyclic Olefin with Soft Nucleophiles

Abstract

A facile method for the synthesis of a new class of disubstituted alkylidenecyclopentenes has been introduced. The methodology involves the palladium-catalyzed ring opening of pentafulvene-derived bicyclic hydrazines with phenols and active methylene compounds, furnishing 1,4-disubstituted alkylidenecyclopentenes in good yield. The utility of multiple points of functionalization was effectively demonstrated by the synthesis of a substituted cyclopentanone and 2-hydrazinofulvene.