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13: 1D Spin Decoupled Experiment

  • Page ID
    332813
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    Homonuclear Spin Decoupled Experiment*

    Sometimes peaks in the 1H NMR overlap. When there is a lot of coupling, it is hard to clearly measure the splitting or identify which peaks are coupled to each other.

    To simplify the spectra, a specific peak will be continuously irradiated so that it is rapidly flipping between spin states. Thus, the other peak (that are coupled to it) do not see it as multiple states and the coupling disappears.

    * All spectra in this unit are simulated

    1H NMR Spectrum:

    clipboard_e7dea0646bb2cd478319c62db49fc17a3.png

    Decoupled Spectrum:

    clipboard_eb6722da4b56f0958ebb5185f6218bd35.png

    Spin Decoupling: 3-aminoacrolein

    Spin Decoupling was used to determine which peak belonged to which hydrogen of 3-aminoacrolein.

    clipboard_ea8db79192a28651437786aad18b95dcc.png

    • Predict the splitting patterns for each H in this structure.
      • HM: _______
      • HA: _______
      • HX: _______
    • If HX is irradiated, which signal will be affected?
    • If HM is irradiated, which signal will be affected?
    • Based on the decoupling experiment, label each peak in the NMR below.

    clipboard_e3a55a8226de2f79dd0490bc390bd847d.png


    This page titled 13: 1D Spin Decoupled Experiment is shared under a not declared license and was authored, remixed, and/or curated by Kate Graham.

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