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    What are the reactants and conditions to go from ethylbenzene to a benzene ring with CH2CH2Cl and what thyp of reaction is it?
    Thanks

    ps has anybody got tips on how to remember all the reactions and conditions. Ive nearlly completed an A3 sheet with all the reactions needed including as and it seems impossible!
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    It is called Friedal-Craft Alkylation
    benzene + RCl --(AlCl3 as catalyst)-----> benzene with the R group attached
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    (Original post by Greendaygirl)
    What are the reactants and conditions to go from ethylbenzene to a benzene ring with CH2CH2Cl and what thyp of reaction is it?
    Thanks

    ps has anybody got tips on how to remember all the reactions and conditions. Ive nearlly completed an A3 sheet with all the reactions needed including as and it seems impossible!
    i THINK.....its a nucleophilic substitution reaction. conditions: chlorine gas, UV light.

    chem is not my best subject but i'm pretty sure it's right...someone please correct me if im wrong.
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    (Original post by keisiuho)
    It is called Friedal-Craft Alkylation
    benzene + RCl --(AlCl3 as catalyst)-----> benzene with the R group attached
    What would the R group be in this case?
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    oops! You are right
    But a mixture of products will be obtained
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    (Original post by Greendaygirl)
    What would the R group be in this case?
    any alkyl group
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    (Original post by keisiuho)
    oops! You are right
    But a mixture of products will be obtained
    I'm right??
    cool.
    yeah...u'll get a mixture of chloroethylbenzenes and dichloroethylbenzenes right?
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    Ths strucuture of the second compound has a douuble bond so is that friedel crafts acylation not alkylation?
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    Wha exam board are you doing p8824?
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    (Original post by p8224)
    I'm right??
    cool.
    yeah...u'll get a mixture of chloroethylbenzenes and dichloroethylbenzenes right?
    There are more, I think.
    The two carbon atoms in the ethyl group can also have Cl atoms attached
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    (Original post by Greendaygirl)
    Ths strucuture of the second compound has a douuble bond so is that friedel crafts acylation not alkylation?
    eh?
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    (Original post by Greendaygirl)
    Wha exam board are you doing p8824?
    not yours thats for sure!...coz my chemistry exam's over!
    CIE (Cambridge Internationaly Exams)
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    phew i was getting really stressed then! thinking i dont have a clue what your talking about! Ill ring one of my mates insted! Thanks anyway.
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    (Original post by keisiuho)
    eh?
    I thought the second structure had an O in it so it would be an acyl chloride
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    So would the R group be ClCH2CH2Cl?
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    Dammit, have to revise all of this again for the synoptic :mad:
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    RCl + C6H6 -----AlCl3---> C6H5R + HCl

    So for ethylbenzene it would

    CH3Ch2Cl + C6H6 ----(AlCl3 catalyst)---> C6H5Ch2Ch3

    This step would be electrophilic substitution (CH3CH2+ is electrophile in this case). Due to delocalised benzene ring, only electrophilic substitution reactions can occur DIRECTLY on the benzene ring. (Exception is hydrogenation/reduction with hydrogen @ 200 degrees C and Nickel catalys)

    (Friedel Krafts is an alternative name for alkylation. ACYLation would involve an acyl chloride RCOCl which acts as a nucleophile not electrophile so won't attack the benzene ring as both will be electron rich)

    To then get C6H5CH2CH2CL you would have to react ethylbenzene with a hydrogen halide in this case HCl. As this does not attack the benzene ring but only the alkyl group and the Cl^- is the attacking particle this will be nucleophilic substitution.
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    (Original post by Greendaygirl)
    What are the reactants and conditions to go from ethylbenzene to a benzene ring with CH2CH2Cl and what thyp of reaction is it?
    Thanks

    ps has anybody got tips on how to remember all the reactions and conditions. Ive nearlly completed an A3 sheet with all the reactions needed including as and it seems impossible!
    just need to check, which board are you doing?.. cos we dont have benzene till unit5
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    (Original post by cipapfatso)
    ACYLation would involve an acyl chloride RCOCl which acts as a nucleophile not electrophile so won't attack the benzene ring as both will be electron rich)
    .
    surely saying that the acid chloride is a nucleophile and is electron rich are contradictory statements. Acid chlorides are nucleophiles (accepted) because of the delta-positive carbon but i think the reason why they dont attack the electron dense benzene ring is because the deltapositive charge is not as great as the positive (+1) charge of the nucleophile created by the Friedel-Crafts mechanism
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    Im doing aqa. so to simplify to get from ethylbenzene to benzene ring with CH2CH2Cl you neeed to add HCl so it attacks the side chain and not hte benzene ring itself?!
 
 
 
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