Total Synthesis of Maoecrystal V: Early-Stage C-H Functionalization and Lactone Assembly by Radical Cyclization

A total synthesis of the unusual ent-kaurane maoecrystal V is described. The Synthesis strategy features a counterintuitive early disconnection of the lactone. subunit to a polycyclic enol ether intermediate in order to preserve the central tetrahydrofuran ring until the beginning stages of the synthesis. This strategy enables an application of C-H functionaliiation at the early phase of the synthesis during the construction of a dihydrobenzofuran intermediate.