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1H-NMR for conformation elucidation

  1. Apr 16, 2014 #1
    I have having some difficulty determining the conformer and assigning H-NMR peaks for a compound with a N,N-diisopropylacetamidine (R-NH-C(CH3)N(2[CH[2(CH3)]])... essentially a diisopropylamine added to CH3CN (ACN). my H-NMR spectrum (at room temp) in CD3CN consists of:
    I have assigned all but the singlets

    B singlet at 5.8ppm R-NH
    B septet at 4.00 CH connected to the N of the diisopropylamine
    singlet 2.37
    singlet 2.15

    TMS at 1.98
    doublet at 1.26ppm methyls from the isopropyl
    Very B singlet -4.9 μ-BHB

    The E conformation is suspected based on theory and steric repulsions, but i cannot justify it from any of the NMR data I have (1H, variable temp 13C, or 11B)

    my best guess in regards to those singles is that both E and unfavorable Z conformations exist in solution.

    Any help would be greatly appreciated.
  2. jcsd
  3. May 4, 2014 #2
    I'm sorry you are not generating any responses at the moment. Is there any additional information you can share with us? Any new findings?
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