On the Reaction of N-Vinyliminophosphoranes with 2,4,6-Cyclooctatrienone. Intermediate Formation of 8-Azabicycloundeca-2,4,7,9-tetraene Ring System.

Article abstract of DOI:10.1246/bcsj.62.2401

The reaction of N-(1-phenylvinyl)iminotriphenylphosphorane and of (1,3,5-cycloheptatrienyl)iminotributylphosphorane with 2,4,6-cyclooctatrienone gave an intermediacy of 8-azabicyclo<5.3.1>undeca-2,4,7,9-tetraene derivatives, which underwent an intramolecular Diels-Alder reaction to construct a tetracyclic ring system.