Palladium-catalyzed carbonylative annulation of o-alkynylphenols: syntheses of 2-substituted-3-aroyl-benzo[b]furans

J Org Chem. 2002 Apr 5;67(7):2365-8. doi: 10.1021/jo010839c.


We report here a general synthetic methodology for palladium-catalyzed carbonylative annulation of o-alkynylphenol to construct 2-substituted-3-aroyl-benzo[b]furan. On the basis of the results, this methodology could be applied to a wider selection of iodide substrates to generate desired products. In accordance with mechanistic studies, this process involves coordination of cationic and less hindered acyl palladium complexes with o-alkynylphenols to create a desired cascade triad (coordination, nucleophilic addition, and reductive elimination). Consistent with this mechanism, addition of 1 equiv of AgBF(4) to palladium catalyst Pd(Ph(3)P)(4) generates an ideal candidate for this unique transformation.

Publication types

  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Benzofurans / chemical synthesis*
  • Catalysis
  • Chemistry, Organic / methods
  • Chromatography, Thin Layer
  • Cyclization
  • Esterification
  • Hydrocarbons, Aromatic / chemistry*
  • Magnetic Resonance Spectroscopy
  • Molecular Structure
  • Palladium / chemistry


  • Benzofurans
  • Hydrocarbons, Aromatic
  • Palladium