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Asymmetric synthesis of seven-membered carbocyclic rings via a sequential oxyanionic 5-exo-dig cyclization/claisen rearrangement process. Total synthesis of (-)-frondosin B.

ABSTRACT: Appropriately substituted nonracemic allyl alcohols, readily prepared from the corresponding enones by application of the CBS methodology, were converted to optically active cycloheptenone derivatives with almost complete transfer of chirality via an efficient "one-pot", cycloisomerization/Claisen rearrangement process. This methodology was directly applied to the expedient total synthesis of (-)-frondosin B.

SUBMITTER: Ovaska TV

PROVIDER: S-EPMC2711515 | biostudies-literature | 2009 Jun

REPOSITORIES: biostudies-literature

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Asymmetric synthesis of seven-membered carbocyclic rings via a sequential oxyanionic 5-exo-dig cyclization/claisen rearrangement process. Total synthesis of (-)-frondosin B.

Ovaska Timo V TV Sullivan Jonathan A JA Ovaska Sami I SI Winegrad Jacob B JB Fair Justin D JD

Organic letters 20090601 12

Appropriately substituted nonracemic allyl alcohols, readily prepared from the corresponding enones by application of the CBS methodology, were converted to optically active cycloheptenone derivatives with almost complete transfer of chirality via an efficient "one-pot", cycloisomerization/Claisen rearrangement process. This methodology was directly applied to the expedient total synthesis of (-)-frondosin B. ...[more]

PMID: 19514798

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