Enantiospecific total synthesis of 6-epi-(−)-hamigeran B. Intramolecular Heck reaction in a sterically constrained environment

An enantiospecific approach, emanating from the abundantly available chiron R-(+)-limonene, to the biologically potent, novel marine natural products, the hamigerans has been developed in which an intramolecular Heck coupling between aryl triflates and an alkene serves as the pivotal step. Following this strategy, a synthesis of (−)-6-epi-hamigeran B has been accomplished.