Synthesis and structural elucidation of diversely functionalized 5,10-diaza[5]helicenes

J Org Chem. 2012 Nov 16;77(22):10176-83. doi: 10.1021/jo301814m. Epub 2012 Nov 1.

Abstract

Diversely functionalized diaza[5]helicenes have been synthesized starting from 6,9-dichloro-5,10-diaza[5]helicene, which was prepared from a readily available quinoline building block via Wittig reaction followed by photochemical electrocyclization. The helicene skeleton was substituted by a variety of O-, S-, N-, and C-centered nucleophiles using nucleophilic aromatic substitution reactions and palladium-catalyzed reactions like Suzuki coupling and Buchwald-Hartwig aminations. We have determined, using X-ray single-crystal diffraction, the crystal structures of the chloro- and methoxy-substituted diaza[5]helicenes. A resolution strategy based on diastereomeric separation by substitution of the dichloro derivative with a chiral amine has been shown.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amines / chemistry*
  • Catalysis
  • Crystallography, X-Ray
  • Molecular Structure
  • Palladium / chemistry
  • Polycyclic Compounds / chemical synthesis*
  • Polycyclic Compounds / chemistry*
  • Stereoisomerism

Substances

  • Amines
  • Polycyclic Compounds
  • helicenes
  • Palladium