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    Is a nucleophile attached to a benzene ring a better nucleophile than the same nucleophile attached to cyclohexane?

    If this is true - why is this?

    Thanks
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    I don't think this generally holds. For example, aminocyclohexane should be more nucleophilic than aniline because the nitrogen is more electron rich, similarly phenols often react through the carbon rather than oxygen becaue the electron density is invested in pi-bonding a lot.
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    Could this be due to the electron withdrawing capabilities of benzene/cyclohexane?

    The more eletron withdrawing the benzene/cyclohexane the less basic it makes the nuclephile (eg NH2). Thus making it a weaker nucleophile and less likely to react?
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    Was about to say the same tgr.

    Makes sense to me, electron deficient benzene (due to delocalisedelectrons, so fewer than normal) withdraws electron density from any surrounding groups making them less good nucleophiles, so on cyclohexane it will alsways be stronger I think.
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    Agreed, the benzene ring being electron withdrawing will probably decrease how nucleophilic something is.
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    (Original post by tgr141291)
    Could this be due to the electron withdrawing capabilities of benzene/cyclohexane?

    The more eletron withdrawing the benzene/cyclohexane the less basic it makes the nuclephile (eg NH2). Thus making it a weaker nucleophile and less likely to react?
    Essentially yes, the nucleophilic heteroatoms have p-orbitals that can overlap with the benzene p-orbitals, creating a pi system that means the heteroatom receives less electron density that it does in substituted cyclohexane.

    Be careful though about using basicity/acidity as a measure of nucleophilicity; yes there is a strong link and good bases are essentially good nucleophiles, but it's not the same thing. A good base is not always a good nucleophile.
 
 
 

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