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Enantioselective total synthesis of clavirolide C. Applications of Cu-catalyzed asymmetric conjugate additions and Ru-catalyzed ring-closing metathesis.

ABSTRACT: The first enantioselective total synthesis of clavirolide C, a member of the dolabellane family of diterpenes isolated from Pacific soft coral Clavularia viridis, is disclosed. The total synthesis features the application of chiral amino acid based ligands in Cu-catalyzed asymmetric conjugate addition (ACA) reactions and a relatively rare application of catalytic ring-closing metathesis to access an 11-membered ring structure. The total synthesis effort has spawned the development of a new protocol for NHC.Cu-catalyzed ACA of alkylaluminum reagents to beta-substituted cycloalkenones. The enantioselective clavirolide C synthesis requires 17 steps (longest linear sequence), affords the target molecule in 3.5% overall yield, and confirms the stereochemical assignment for the natural product.

SUBMITTER: Brown MK

PROVIDER: S-EPMC2628296 | biostudies-literature | 2008 Oct

REPOSITORIES: biostudies-literature

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Enantioselective total synthesis of clavirolide C. Applications of Cu-catalyzed asymmetric conjugate additions and Ru-catalyzed ring-closing metathesis.

Brown M Kevin MK Hoveyda Amir H AH

Journal of the American Chemical Society 20080909 39

The first enantioselective total synthesis of clavirolide C, a member of the dolabellane family of diterpenes isolated from Pacific soft coral Clavularia viridis, is disclosed. The total synthesis features the application of chiral amino acid based ligands in Cu-catalyzed asymmetric conjugate addition (ACA) reactions and a relatively rare application of catalytic ring-closing metathesis to access an 11-membered ring structure. The total synthesis effort has spawned the development of a new proto ...[more]

PMID: 18778057

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