Stereoselective total synthesis of (±)-α-vetispirene, (±)-hinesol, and (±)-β-vetivone based on a Claisen rearrangement

The stereoselective total syntheses of (±)-α-vetispirene, (±)-hinesol, and (±)-β-vetivone were accomplished based on a Claisen rearrangement in an alkenyl bicyclic dihydropyran system. The most striking feature of this approach is that the Claisen rearrangement of bicyclic dihydropyran proceeds stereoselectively to provide a multi-functionalized spiro4.5]decane, which is an efficient precursor for the synthesis of the vetivane sesquiterpenes.