Highly enantioselective synthesis of γ-, δ-, and ε-chiral 1-alkanols via Zr-catalyzed asymmetric carboalumination of alkenes (ZACA)-Cu- or Pd-catalyzed cross-coupling

Proc Natl Acad Sci U S A. 2014 Jun 10;111(23):8368-73. doi: 10.1073/pnas.1401187111. Epub 2014 May 27.

Abstract

Despite recent advances of asymmetric synthesis, the preparation of enantiomerically pure (≥99% ee) compounds remains a challenge in modern organic chemistry. We report here a strategy for a highly enantioselective (≥99% ee) and catalytic synthesis of various γ- and more-remotely chiral alcohols from terminal alkenes via Zr-catalyzed asymmetric carboalumination of alkenes (ZACA reaction)-Cu- or Pd-catalyzed cross-coupling. ZACA-in situ oxidation of tert-butyldimethylsilyl (TBS)-protected ω-alkene-1-ols produced both (R)- and (S)-α,ω-dioxyfunctional intermediates (3) in 80-88% ee, which were readily purified to the ≥99% ee level by lipase-catalyzed acetylation through exploitation of their high selectivity factors. These α,ω-dioxyfunctional intermediates serve as versatile synthons for the construction of various chiral compounds. Their subsequent Cu-catalyzed cross-coupling with various alkyl (primary, secondary, tertiary, cyclic) Grignard reagents and Pd-catalyzed cross-coupling with aryl and alkenyl halides proceeded smoothly with essentially complete retention of stereochemical configuration to produce a wide variety of γ-, δ-, and ε-chiral 1-alkanols of ≥99% ee. The MαNP ester analysis has been applied to the determination of the enantiomeric purities of δ- and ε-chiral primary alkanols, which sheds light on the relatively undeveloped area of determination of enantiomeric purity and/or absolute configuration of remotely chiral primary alcohols.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Acetylation
  • Alcohols / chemical synthesis*
  • Alcohols / chemistry
  • Alcohols / metabolism
  • Alkenes / chemistry*
  • Aluminum Compounds / chemistry
  • Carbon / chemistry
  • Catalysis
  • Copper / chemistry*
  • Lipase / metabolism
  • Models, Chemical
  • Molecular Structure
  • Oxidation-Reduction
  • Palladium / chemistry*
  • Stereoisomerism
  • Zirconium / chemistry*

Substances

  • Alcohols
  • Alkenes
  • Aluminum Compounds
  • Palladium
  • Carbon
  • Copper
  • Zirconium
  • Lipase