Synthesis of an Advanced Intermediate for (+)-Pillaromycinone. Staunton−Weinreb Annulation Revisited

Condensation of an orsellinate anion with a 2-cyclohexenone (Staunton−Weinreb annulation) afforded a linear tetracycle which was converted to a protected derivative of 12a-epipillaromycinone. Methodology for introducing a 12a-hydroxyl substituent into the tetracycle with correct (R) configuration is described.