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    In 2,3-dimethylbutane, how much splitting would occur with the two hydrogens on the middle carbon atoms?
    Would this cause splitting into 7 or 13 peaks?
    I'm not sure which one it is because each of those two hydrogen atoms are only surrounded by 6 chemically different hydrogen atoms, but in total there are 13.

    Thank you in advance
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    7 subpeaks.

    Did you get 13 from counting all the hydrogens in the molecule?
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    The two central H atoms are in the same environment as each other, so won't split each other - in the same way as the two atoms in the centre of a propane molecule find themselves in the same environment, so don't split each other. OK, so the two H atoms in 2,3-dimethylbutane find themselves attached to different C atoms, but they still are in the same environment as each other.

    Each H atom therefore has six adjacent hydrogens, so would split as a heptet.

    This is ace: www.nmrdb.org/ (use the 1H predictor)
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    (Original post by Pigster)
    The two central H atoms are in the same environment as each other, so won't split each other - in the same way as the two atoms in the centre of a propane molecule find themselves in the same environment, so don't split each other. OK, so the two H atoms in 2,3-dimethylbutane find themselves attached to different C atoms, but they still are in the same environment as each other.

    Each H atom therefore has six adjacent hydrogens, so would split as a heptet.

    This is ace: www.nmrdb.org/ (use the 1H predictor)
    Thank you very much!

    (Original post by h3rmit)
    7 subpeaks.

    Did you get 13 from counting all the hydrogens in the molecule?
    I got it from adding 1 to the number of chemically different hydrogen atoms on adjacent carbon atoms. I can see now though that that doesn't make sense.
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    (Original post by jamesthelam)
    I got it from adding 1 to the number of chemically different hydrogen atoms on adjacent carbon atoms. I can see now though that that doesn't make sense.
    Adjacent carbon atoms have to be directly adjacent to the single carbon atom you're looking at

    Glad you get it now
 
 
 
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