Synthesis and photophysical properties of biphenyl and terphenyl arylene-ethynylene macrocycles

J Org Chem. 2014 Feb 21;79(4):1594-610. doi: 10.1021/jo4023809. Epub 2014 Feb 7.

Abstract

A series of single-walled carbon nanotube precursors, C3h-symmetric cyclotri(ethynylene)(biphenyl-2,4'-diyl) and cyclotri(ethynylene)(p-terphenyl-2,4″-diyl), have been prepared by a linear stepwise oligomerization-cyclization route and by statistical intermolecular cyclooligomerization. In addition to producing these members of a novel class of arylene ethynylene macrocycles, 1 and 2, the latter statistical process produces the smaller cyclic dimer, cyclodi(ethynylene)(p-terphenyl-2,4″-diyl) and the larger cyclic tetramer cyclotetra(ethynylene)(biphenyl-2,4'-diyl). These macrocycles display large Stokes shifts in their fluorescence spectra. Their biphenyl or terphenyl connectivity prevents these macrocycles from achieving full planarity in the ground state, and the ethynylene moieties could provide synthetic access to cyclic arylene oligomers and discrete carbon nanotube segments.

Publication types

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

MeSH terms

  • Alkynes / chemistry*
  • Biphenyl Compounds / chemical synthesis*
  • Biphenyl Compounds / chemistry
  • Fluorescence
  • Macrocyclic Compounds / chemical synthesis*
  • Macrocyclic Compounds / chemistry
  • Molecular Structure
  • Nanotubes, Carbon / chemistry
  • Photochemical Processes
  • Terphenyl Compounds / chemical synthesis*
  • Terphenyl Compounds / chemistry

Substances

  • Alkynes
  • Biphenyl Compounds
  • Macrocyclic Compounds
  • Nanotubes, Carbon
  • Terphenyl Compounds