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An Unexpected Transannular [4+2] Cycloaddition during the Total Synthesis of (+)-Norcembrene?5.

ABSTRACT: We report a concise and versatile total synthesis of the diterpenoid (+)-norcembrene?5 from simple building blocks. Ring-closing metathesis and an auxiliary-directed 1,4-addition are the key steps of our synthetic route. During the synthesis, an unprecedented, highly oxidized pentacyclic structural motif was established from a furanocembranoid through transannular [4+2] cycloaddition.

SUBMITTER: Breunig M

PROVIDER: S-EPMC7155007 | biostudies-literature | 2020 Mar

REPOSITORIES: biostudies-literature

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An Unexpected Transannular [4+2] Cycloaddition during the Total Synthesis of (+)-Norcembrene 5.

Breunig Michael M Yuan Po P Gaich Tanja T

Angewandte Chemie (International ed. in English) 20200211 14

We report a concise and versatile total synthesis of the diterpenoid (+)-norcembrene 5 from simple building blocks. Ring-closing metathesis and an auxiliary-directed 1,4-addition are the key steps of our synthetic route. During the synthesis, an unprecedented, highly oxidized pentacyclic structural motif was established from a furanocembranoid through transannular [4+2] cycloaddition. ...[more]

PMID: 31750980

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