2. Academic Validation
  3. Enantioselective total synthesis of cyathin A3

Enantioselective total synthesis of cyathin A3

  • Org Lett. 2007 Jul 19;9(15):2843-6. doi: 10.1021/ol070994z.
Dale E Ward 1,  Jianheng Shen
Affiliations

Affiliation

  • 1 Department of Chemistry, University of Saskatchewan, 110 Science Place, Saskatoon, Canada. dale.ward@usask.ca
PMID: 17580883 DOI: 10.1021/ol070994z
Abstract

The total synthesis of (-)-cyathin A3 is described. The key step involves an unusual enantioselective Diels-Alder reaction of 2,5-dimethyl-1,4-benzoquinone with 2,4-bis(trimethylsilyloxy)-1,3-pentadiene, using Mikami's catalyst [(R)-BINOL + Cl2Ti(OiPr)2 + 4 A mol sieves] modified by addition of Mg and SiO2. Because cyathin A3 is easily transformed into allocyathin B3, cyathin B3, cyathin C3, and neoallocyathin A4, this route also constitutes formal syntheses of these Natural Products.

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