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Homework Help: Organic question

  1. Apr 14, 2008 #1
    1. The problem statement, all variables and given/known data

    Salbutamol is as shown below. (i managed the display off google which is similar to that of the book)

    http://upload.wikimedia.org/wikipedia/commons/thumb/f/f1/Salbutamol-2D-skeletal.png/800px-Salbutamol-2D-skeletal.png" [Broken]

    except for the cyclic ring is a benzene ring in the book and the alkyl group to the roght of the nitrogen is represented as R. (R is an alkyl group which for the purpose of this question does not affect the rest of the molecule)

    (a) Name four reactive organic groups in salbutamol.
    (b) State 2 of these groups which are affected by mild oxidation, and what groups are produced.
    (c) Would you expect the salbutamol molecule to be acidic, neutral or alkaline?

    2. Relevant equations

    3. The attempt at a solution

    (a) i identified the hydroxyl group, benzene ring, amino group, and alkyl group.

    But i'm not sure if this is correct.

    (b) the hydroxyl group will be oxidised to either a ketone or an aldehyde by mild oxidation.

    i can't find a second one.

    (c) the molecule is alkaline because of the basic -NH- group
    Last edited by a moderator: May 3, 2017
  2. jcsd
  3. Apr 14, 2008 #2
    (a) Amine not Amino group

    (b) Benzyl Alcohol can be oxidized to benzoic acid as there is benzylic hydrogen present.
  4. Apr 14, 2008 #3
    are there any other reactive groups in the molecule?
  5. Apr 14, 2008 #4


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    I believe that the question is asking only for the reactive groups. That eliminates the benzene and the alkyl groups. Heteroatoms are generally regarded as more reactive than aromatic groups and alkyl groups.

    What might you do with the phenol?
  6. Apr 14, 2008 #5
    i don't think phenol can be oxidised. i read that somewhere in my notes...
  7. Apr 14, 2008 #6
    i really don't know what to write besides these groups... :-s

    maybe a phenolic group instead of the benzene ring.
  8. Apr 14, 2008 #7
    Phenol wouldn't oxidize under mild conditions... it may have something to do with a property of benzene...

    Both of the other OH groups are alcohols. One makes a ketone and one makes an aldehyde...
  9. Apr 14, 2008 #8


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    Google "phenol oxidation". First hit...
  10. Apr 14, 2008 #9
    oo yeah, phenols CAN be oxidised....
  11. Apr 15, 2008 #10
    The first hit doesn't work; it brings me to a blank page.

    I highly doubt that the phenyl OH group will be oxidized more readily than the primary and secondary alcohols, especially in the same conditions for these (such as Jones reagent or CrO3/H2SO4); the end product would be antiaromatic and destablilize the molecule. Nonetheless, it would produce a ketone.
  12. Apr 16, 2008 #11
    the phenol would not be oxidised by a mild OA
  13. Apr 16, 2008 #12


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    Phenols are oxidized by AIR! That's pretty mild. Much more mild than chromium oxidation!
  14. Apr 16, 2008 #13


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    Quinones are almost aromatic.
    Last edited: Apr 16, 2008
  15. Apr 16, 2008 #14
    aaaahh..... ok.... nice. i didn't know!!
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