A Strong cis-Effect in an Imidazole-Imidazolium-Substituted Alkene.

  title={A Strong cis-Effect in an Imidazole-Imidazolium-Substituted Alkene.},
  author={D. C. Georgiou and Mohammad A Haghighatbin and C. Hogan and M. Scholz and J. Bull and E. Bieske and David J. D. Wilson and J. Dutton},
  journal={Angewandte Chemie},
  volume={56 29},
We report the first example of an alkene with two carbon-bound substituents (imidazole and imidazolium rings) where the Z-isomer has a greater thermodynamic stability than the E-isomer which persists in both the gas phase and in solution. Theoretical calculations, solution fluorescence spectroscopy and gas-phase ion mobility mass spectrometry studies confirm the preference for the Z-isomer, the stability of which is traced to a non-covalent interaction between the imidazole lone pair and the… Expand
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