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Homework Help: An SN2 reaction products

  1. Dec 19, 2012 #1
    1. The problem statement, all variables and given/known data

    Find the substitution products of ( 2S, 3S)-2-chloro-3-methylpentane + CH3O- in SN2 reaction.

    3. The attempt at a solution

    Will the anti-attack of the nucleophile result in the change of S to R for both the chiral carbons or just for the one with Cl connected to it? How can I know this?
  2. jcsd
  3. Dec 19, 2012 #2
    The configuration of the carbon attached with Cl changes. The configuration changes only when the bonds to the chiral carbon break or change.
  4. Dec 19, 2012 #3
    So I'll get (2R,3S)-3-methyl-2-pentanol?
  5. Dec 19, 2012 #4
    How do you get an alcohol? Shouldn't that be an ether?
  6. Dec 19, 2012 #5
    How can it be ether? Cl is the leaving group and you get OH that is attached to the Cl's carbon from the other side. Now This carbon is directly attached to O, H, R and R', I don't see how the oxygen can be attached to 2 carbons to form ether...
  7. Dec 19, 2012 #6


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    Williamson ether synthesis.
  8. Dec 19, 2012 #7
  9. Jan 8, 2013 #8
    You said in your first post that the nucleophile was CH3O-, not OH-. This would account for a carbon on one side of the oxygen. As this nucleophile attacks, it kicks away a Cl-, causing inversion of configuration and a new bond to carbon. That makes the oxygen bridge two carbons, forming an ether. I believe the correct answer would be (2R, 3S)-3-methyl-2-methoxypentane.
    Last edited: Jan 8, 2013
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