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    we have do identify this diamine, molecular formula C6H14N2, it has one double bond equivalent and no shifts that could be an alkene so I think its cyclic. My best guess is cyclohexane -1,2-diamine but I'm not sure. can anyone help please?
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    (Original post by jacksonmeg)
    we have do identify this diamine, molecular formula C6H14N2, it has one double bond equivalent and no shifts that could be an alkene so I think its cyclic. My best guess is cyclohexane -1,2-diamine but I'm not sure. can anyone help please?
    The slight problem (as I see it) with cyclohexane-1,2-diamine is that you would have four equivalent protons in the 3,6 positions and 4 equivalent in the 4,5 positions. You should only have three signals (apart from the amine signals) and you have five. Your spectrum has a series of non-equivalent CH2 protons.

    That there are two NH2 groups seems probable as four protons disapear after the D2O shake.

    ... after further thought it occurs to me that the axial protons and equatorial protons in (for example cyclohexane-trans-1,4-diamine will have slightly different shifts, giving 5 groups of equivalent protons rather than three.

    The trans-1,2-diamine isomer also gives rise to five environments (not counting the NH2 groups)

    I can't see any way to split them (if you pardon the pun) ...
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    Yeah, it must be the trans isomer. I bet both amines being equatorial pretty much locks in that conformer. The trans 1,2 diamine is the only one that can give you the right number of environments so seems to match pretty well - 1,3 cis would give you 7, and 1,4 trans would only give 3 environments (excluding the amines).
 
 
 
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