Highly enantioselective Diels-Alder reactions of Danishefsky type dienes with electron-deficient alkenes catalyzed by Yb(III)-BINAMIDE complexes

J Am Chem Soc. 2008 Sep 24;130(38):12588-9. doi: 10.1021/ja804430n. Epub 2008 Aug 30.

Abstract

1-Methoxy-3-trimethylsiloxy-1,3-butadiene (Danishefsky's diene) is recognized as a synthetically useful diene due to its high reactivity in the Diels-Alder reaction with electron-deficient alkenes to give oxygen-functionalyzed cyclohexenes and substituted cyclohexenones, which are important building blocks for the total synthesis of natural products. However, the development of catalytic enantioselective versions of Diels-Alder reactions using Danishefsky type dienes with electron-deficient alkenes has been difficult because of the instability of the dienes under Lewis acidic conditions. Only highly reactive CO and CN double bonds are employed in a hetero-Diels-Alder reaction which proceeds under catalysis of chiral Lewis acids. We have developed a new chiral ligand, BINAMIDE, which is easily prepared from 1,1'-binaphtyl-2,2'-diamine by acylation. The highly diastereo- and enantioselective Diels-Alder reaction of Danishefsky type dienes with electron-deficient alkenes in the presence of an Yb(III)-BINAMIDE complex has been developed. The reaction proceeded in an exoselective mode and gave chiral highly functionalized cyclohexene derivatives in good yields.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Alkenes / chemistry*
  • Amides / chemistry
  • Butadienes / chemistry*
  • Catalysis
  • Cyclohexanones / chemical synthesis*
  • Cyclohexenes / chemical synthesis*
  • Ligands
  • Naphthalenes / chemistry
  • Organometallic Compounds / chemistry
  • Stereoisomerism
  • Ytterbium / chemistry

Substances

  • Alkenes
  • Amides
  • Butadienes
  • Cyclohexanones
  • Cyclohexenes
  • Ligands
  • Naphthalenes
  • Organometallic Compounds
  • Ytterbium