Palladium(II)-catalyzed oxidative C-H/C-H coupling and eliminative S(N)(H) reactions in direct functionalization of imidazole oxides with indoles

J Org Chem. 2012 Oct 19;77(20):9087-93. doi: 10.1021/jo301618b. Epub 2012 Oct 1.

Abstract

Two novel synthetic approaches to realize the direct C(sp(2))-H bond functionalization in cyclic nitrones are reported. Palladium(II)-catalyzed oxidative C-C coupling of 2,2-dialkyl-4-phenyl-2H-imidazole 1-oxides with indoles was shown to result in the formation of 5-indolyl-3-yl derivatives, while nucleophilic substitution of hydrogen (S(N)(H)) at C(5) of the same imidazole system was found to afford the corresponding deoxygenated compounds.

MeSH terms

  • Azo Compounds / chemical synthesis*
  • Azo Compounds / chemistry
  • Catalysis
  • Imidazoles / chemistry*
  • Indoles / chemistry*
  • Molecular Structure
  • Organometallic Compounds / chemistry*
  • Oxidation-Reduction
  • Oxides / chemistry*
  • Palladium / chemistry*
  • Thiosemicarbazones / chemical synthesis*
  • Thiosemicarbazones / chemistry

Substances

  • Azo Compounds
  • Imidazoles
  • Indoles
  • Organometallic Compounds
  • Oxides
  • Thiosemicarbazones
  • azomethine
  • Palladium