Total synthesis of (±)−paralemnolin A

Abstract

The first total synthesis of chlorinated tricyclic norsesquiterpenoid paralemnolin A in racemic form was achieved. The synthesis features chlorolactonization of a cyclohexene derivative having a tert-butyl ester, construction of the novel tricyclic skeleton by an intramolecular Reformatsky–Honda reaction, and methylenation of the carbonyl group of the lactone moiety with Tebbe reagent.