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Stereoselective total synthesis of hainanolidol and harringtonolide via oxidopyrylium-based [5 + 2] cycloaddition.

ABSTRACT: The tetracyclic carbon skeleton of hainanolidol and harringtonolide was efficiently constructed by an intramolecular oxidopyrylium-based [5 + 2] cycloaddition. An anionic ring-opening strategy was developed for the cleavage of the ether bridge in 8-oxabicyclo[3.2.1]octenes derived from the [5 + 2] cycloaddition. Conversion of cycloheptadiene to tropone was realized by a sequential [4 + 2] cycloaddition, Kornblum-DeLaMare rearrangement, and double elimination. The biomimetic synthesis of harringtonolide from hainanolidol was also confirmed.

SUBMITTER: Zhang M

PROVIDER: S-EPMC3798225 | biostudies-literature | 2013 Aug

REPOSITORIES: biostudies-literature

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Stereoselective total synthesis of hainanolidol and harringtonolide via oxidopyrylium-based [5 + 2] cycloaddition.

Zhang Min M Liu Na N Tang Weiping W

Journal of the American Chemical Society 20130809 33

The tetracyclic carbon skeleton of hainanolidol and harringtonolide was efficiently constructed by an intramolecular oxidopyrylium-based [5 + 2] cycloaddition. An anionic ring-opening strategy was developed for the cleavage of the ether bridge in 8-oxabicyclo[3.2.1]octenes derived from the [5 + 2] cycloaddition. Conversion of cycloheptadiene to tropone was realized by a sequential [4 + 2] cycloaddition, Kornblum-DeLaMare rearrangement, and double elimination. The biomimetic synthesis of harringt ...[more]

PMID: 23930656

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