Sesquiterpene lactones are natural stereochemically pure compounds, which show a number of biological activities. In order to study the reactivity of sesquiterpene lactones in biological systems, we describe herein the asymmetric synthesis of a simple model, the α-methylene-hexahydrobenzofuranone 1, which includes the α-methylene-γ-butyrolactone moiety and presents all the different possible ring junctions.