An Enantioselective Approach to Furanoeremophilanes: (+)‑9‑Oxoeuryopsin

Abstract

An enantioselective total synthesis of the furanoeremophilane sesquiterpene (+)-9-oxoeuryopsin <b>1</b> is reported. The synthesis involves as a key step a copper­(II) triflate catalyzed tandem asymmetric conjugate addition of AlMe₃ to 2-methyl-2-cyclohexen-1-one with the Feringa (<i>S</i>,<i>R,R</i>)-phosphoramidite binaphthol ligand, followed by aldol condensation of the resulting aluminum enolate with 4-methyl-3-furaldehyde <b>4</b>. This tandem transformation has not been previously reported with a 2-substituted-2-cyclohexen-1-one. Conventional functional group manipulations completed the synthesis