Synthesis and stacked conformations of symmetrical and unsymmetrical oligo-ureas of metaphenylenediamine

J Org Chem. 2007 Mar 30;72(7):2302-8. doi: 10.1021/jo061989w. Epub 2007 Mar 8.

Abstract

The addition of substituted anilines to nitro-substituted isocyanates followed by reduction generates new aniline-substituted ureas, which can be further extended in a one- or two-directional iterative manner to form oligomeric ureas based on a m-phenylenediamine monomer. Oligo-ureas with up to eight urea linkages are reported. Fully N-substituted oligo-ureas are crystalline, and the X-ray crystal structures display ring-stacked conformations. 1H NMR studies indicate that the stacked conformation persists in solution.

MeSH terms

  • Methylation
  • Models, Molecular
  • Molecular Conformation
  • Phenylenediamines / chemistry*
  • Stereoisomerism
  • Urea / chemical synthesis
  • Urea / chemistry*

Substances

  • Phenylenediamines
  • Urea