The total synthesis of (-I)-isonootkatone (a-vetivone) is described. The key step invoIves annelation of 4-isopropylidene-2-carbomethoxycyclohexanone with trans-3-penten-2-one to give the bicyclic enone with cisrelated CHs and COICH~ substituents. A study on the stereochemistry of this reaction using 2-carbomethoxycyclohexanone as the keto ester component showed that the cis isomer was favored in tert-butyl and tert-amyl alcohol at ...
