Executive Summary : | The (+)-Waihoensene is a diterpene containing a highly strained tetracyclic core, decorated with six consecutive stereocenters; four of which are quaternary carbons. We have proposed the enantioselective route to the total synthesis of (+)-Waihoensene using Hajosh-Parrish ketone analogues as key intermediates. The key steps in this proposal features diastereoselective radical cyclization and intramolecular carbene mediated stetter reaction to get tricyclic core, Michael addition or Robinson annulation to construct Hajos-Parrish ketone analogues and three component reductive alkylation (TCRA) to couple both aldehyde and 1,3- cyclopentanedione. The proposed enantioselective strategy will lay the groundwork for the synthesis of other diterpene natural products. |