Synthetic Studies of Daphniphyllum Alkaloids: A New Method for the Construction of [7-5-5] All-Carbon Tricyclic Skeleton

Abstract

Abstract Daphniphyllum alkaloids have complex molecular structures; consequently, their synthesis can be challenging. A new method for the construction of the [7-5-5] tricyclic core of Daphniphyllum alkaloids was developed. The bicyclo[5.3.0]decane skeleton was constructed through a divinylcyclopropane rearrangement of a cyclopentenone derivative with a vinylcyclopropyl group at the β-position. After introduction of a 2-iodoethyl group by a regioselective Michael addition with phenyl vinyl selenone, the [7-5-5] tricyclic system was formed by intramolecular alkylation of a cyclopentadienyl anion species.