Selective Heck arylation of cyclohexene with homogeneous and heterogeneous palladium catalysts

Molecules. 2010 Mar 25;15(4):2166-77. doi: 10.3390/molecules15042166.

Abstract

Palladium catalysts containing Pd(II) supported on Al2O3 and alumina-based mixed oxides, Al2O3-ZrO2, Al2O3-CeO2, and Al2O3-Fe2O3, are very effective in the Heck coupling of iodobenzene with cyclohexene in DMF solution. The best results, up to 81% of monoarylated products with a selectivity to 4-phenylcyclohexene (3) close to 90% were obtained with KOH as a base. The catalytic activity of palladium supported on alumina-based oxides was compared with that of homogeneous precursors, such as Pd(OAc)2 and PdCl2(PhCN)2, used in [Bu4N]Br as the reaction medium. Under such conditions homogeneous systems were more selective and produced up to 60% of monoarylated products with a selectivity to 3 close to 60%.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Acetates / chemistry*
  • Aluminum Oxide / chemistry
  • Catalysis
  • Cyclohexanes / chemistry*
  • Cyclohexenes / chemistry*
  • Iodobenzenes / chemistry*
  • Organometallic Compounds / chemistry*
  • Palladium / chemistry*

Substances

  • Acetates
  • Cyclohexanes
  • Cyclohexenes
  • Iodobenzenes
  • Organometallic Compounds
  • palladium(II) acetate
  • cyclohexene
  • Palladium
  • iodobenzene
  • 4-phenylcyclohexene
  • Aluminum Oxide
  • palladium chloride