Total asymmetric syntheses of β-hydroxy-δ-lactones via Umpolung with sulfur dioxide

J Org Chem. 2011 Feb 4;76(3):840-5. doi: 10.1021/jo102035d. Epub 2011 Jan 10.

Abstract

Cyclic stereotriads and stereotetrads of the β-hydroxy-δ-lactone type, e.g. prelactones B and E, common in polyketides and polypropionates, are prepared via SO(2)-induced oxyallylations of enoxysilanes with (1E,3Z)-1-(1-phenylethoxy)penta-1,3-dien-3-yl carboxylates. Using (Z)- or (E)-enoxysilanes both 4,5-cis- or 4,5-trans-δ-lactones are obtained. Depending on the reduction method applied to the obtained aldol intermediates 5,6-trans or 5,6-cis-derivatives are formed. The δ-lactones can be prepared in both their enantiomeric forms depending on the (1R)- or (1S)-configuration of the starting 1-(1-phenylethoxy)penta-1,3-dienes.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Alkadienes / chemistry*
  • Lactones / chemical synthesis*
  • Lactones / chemistry*
  • Magnetic Resonance Spectroscopy
  • Molecular Structure
  • Stereoisomerism
  • Sulfur Dioxide / chemistry*

Substances

  • Alkadienes
  • Lactones
  • Sulfur Dioxide