Stereochemistry of intermolecular oxypalladation: Pd(II)-catalyzed 1,3-chirality transfer reaction of chiral allylic alcohol with methanol

J Org Chem. 2009 Aug 7;74(15):5174-80. doi: 10.1021/jo9011464.

Abstract

The intermolecular oxypalladation of chiral nonracemic allylic alcohols (S)-1, (R)-1, and (R)-3 in methanol gave chiral nonracemic methyl allyl ethers (S)-2 and/or (R)-2 with excellent selectivity. The reaction induced the 1,3-chirality transfer to give syn-S(N)2' product exclusively through syn oxypalladation. On the other hand, the anti-S(N)2' product was produced in 20-33% in THF, toluene, and CH2Cl2 and predominantly in CH3CN. The pi-olefin-Pd complexes I and II are proposed as important intermediates to explain the syn- and anti-oxypalladation pathways. The byproduct 9 was formed through the second syn-oxypalladation from the methyl allyl ether 2, though the rate of this second reaction was far slower than that of allylic alcohol.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Catalysis
  • Ethers / chemical synthesis
  • Ethers / chemistry*
  • Methanol / chemistry*
  • Molecular Structure
  • Organometallic Compounds / chemistry*
  • Palladium / chemistry*
  • Propanols / chemistry*
  • Stereoisomerism

Substances

  • Ethers
  • Organometallic Compounds
  • Propanols
  • allyl alcohol
  • Palladium
  • Methanol