Intramolecular Diels-Alder reactions using chiral ruthenium Lewis acids and application in the total synthesis of ent-ledol

Org Biomol Chem. 2011 Nov 7;9(21):7564-70. doi: 10.1039/c1ob06121f. Epub 2011 Sep 22.

Abstract

One-point binding chiral ruthenium Lewis acids incorporating the C(2)-symmetric electron-poor bidentate phosphinite ligand BIPHOP-F and a Cp or an indenyl 'roof' can efficiently catalyze asymmetric intramolecular Diels-Alder reactions of trienes to form bicyclic adducts with good to excellent asymmetric induction. This reaction forms the key step in a total synthesis of ent-ledol in 96% ee. The synthesis also helps to clarify the stereochemical assignment of ledol and inconsistencies in the measured optical rotation.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Lewis Acids / chemistry*
  • Models, Molecular
  • Molecular Conformation
  • Organometallic Compounds / chemistry*
  • Ruthenium / chemistry*
  • Sesquiterpenes / chemical synthesis*
  • Sesquiterpenes / chemistry
  • Stereoisomerism

Substances

  • Lewis Acids
  • Organometallic Compounds
  • Sesquiterpenes
  • Ruthenium
  • ledol