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organic question

Discussion in 'DAT Discussions' started by mindblowing, Jun 16, 2008.

  1. mindblowing

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    whats the differnce between electrophilic addition and free redical addition of bromine to benzene ...i thought its same?
    which one is markovniov and which one is anti markovnikov
     
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  3. Mstoothlady2012

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    electrophilic addition gives markovnikov

    free radical gives non-markvonikov
     
  4. doc3232

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    Markovnikov and anti-M doesn't apply to benzenes.
    Electrophilic addition does not use radicals. Instead electrons from benzene attack the electrophile then an H leaves the ring, and electrons rebuild the aromatic ring.
     
  5. excusezmoi

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    Electrophilic will give Markovnikov 3>2>1
    Free Radical; Br is with Peroxide or ROOR it will yield to Anti-Markovinkov 1>2>3 but this is only in Br though it won't work for the others like Cl, I , F (as I remember), these guys would yield Markovnikov...somebody correct me if I'm wrong.
     
  6. 250rsavage

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    I thought Br attacks the most substituted C: Markovnikov , while Cl is anti-Markovnikov and will attack the least substituted

    Or is this only for cylco rings and not benzene rings
     
  7. doc3232

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    Benzenes are completely different than all others. I don't think there any radical reactions with benzenes on the actual ring itself. Only at the benzylic position because it is very stable.
     
  8. 250rsavage

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    This is from Kaplan BB:
    in ROOR (peroxide), Br disobeys markovnikov rule, but Cl and I are not effected,

    Normally Br follows markovnikov, but when it is with ROOR it follows anit-markovnikov rules.

    Does this mean Br and Cl follows markovnikov rules normally . But when Br is in ROOR it follows anti-markovnikov rules and Cl is never affected either way it will always follow markovnikov rules
     

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