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    I'm analysing a mass spectrum i've been given for a molecule with the molecular formula of C9H10O2.

    The structure iv deduced is a Benzene ring with COOC2H5 substituent.

    so its... Benzene-C(=O)-O-C2H5

    I'm working out the fragments shown on the mass spec. Those given to me are 150, 122, 105, 77, 51.

    So far, i've deduced:
    150 - the molecule as it is
    122 - the molecule loses C2H2 (ethene) and leaves an alcohol
    105 - the molecule loses C2H5O' (an Ethoxy radical)
    77 - the molecule loses the whole substituent of C(=O)-O-C2H5 and leaves an Benzene ring

    The problem is, i cant work out the 51 peak? What is lost here? Can a benzene ring be broken - to my knowledge it is stable and hence would not fragment?

    Please help me on this
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    Forgive my poor spelling in the thread title please
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    any chance of a pic of the spectra?
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    (Original post by gingerbreadman85)
    any chance of a pic of the spectra?
    i've uploaded it onto google docs for you

    spectra assignment

    That is the whole assignment, and includes the mass spec.
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    (Original post by killacam2)
    i've uploaded it onto google docs for you

    spectra assignment

    That is the whole assignment, and includes the mass spec.
    The [C4H3]+ ion is a characteristic of phenyl fragmentation, i.e. a benzene ring breakdown and rearrangement.
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    (Original post by charco)
    The [C4H3]+ ion is a characteristic of phenyl fragmentation, i.e. a benzene ring breakdown and rearrangement.
    Thank you so much!

    this is what i was wondering, whether phenyl fragmentation can occur.

    I haven't come across this before.

    Are you a chemistry student at university?
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    (Original post by killacam2)
    Thank you so much!

    this is what i was wondering, whether phenyl fragmentation can occur.

    I haven't come across this before.

    Are you a chemistry student at university?
    no
 
 
 
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