First asymmetric synthesis of both enantiomers of andirolactone

Abstract

We have achieved the first asymmetric synthesis of (+)- and (−)-andirolactone. The key steps were separation of limonene oxide diastereomers, asymmetric oxidation induced by the chiral intermediate and ring-closing metathesis in the presence of catalytic amounts of Lewis acid to form the spirocyclic butenolides.