Further Synthetic Studies Towards the Austrodorane Skeleton: Synthesis of Austrodoral

Abstract

AbstractThe synthesis of austrodoral (1), a marine nor‐sesquiterpene that contains a unique bicyclic skeleton, has been achieved. The synthetic strategy is based on the ring contraction of a suitable optically active drimanic epoxy derivative, obtained from commercially available (+)‐sclareolide (4). Fluorosulfonic acid was found to promote the ring contraction efficiently. The nor‐sesquiterpene hydrocarbon 13, a key intermediate in the synthesis of sesquiterpene hydroquinones, has also been prepared in optically active form. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2005)