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    Why is ammonia a stronger base than an aromatic amine?
    I don't quite understand. I've read it has something to do with the benzene ring. If someone could explain it to me it would be appreciated.

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    The lone electron pair on the nitrogen atom in benzene get partially delocalised into the benzene ring.this means that there is less electron density around the N atom This makes the lone pair on the N atom in phenylamine less available for coordinate bonding so it is a weaker base.
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    As B_9710 said.

    Here's a diagram to illustrate it





    If the lone pair of electrons tries to make a coordinate bond to a proton, it will break the delocalisation/resonance energy of the benzene ring/
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    (Original post by B_9710)
    The lone electron pair on the nitrogen atom in benzene get partially delocalised into the benzene ring.this means that there is less electron density around the N atom This makes the lone pair on the N atom in phenylamine less available for coordinate bonding so it is a weaker base.
    Is there a reason to why it gets partially delocalised in the ring?
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    (Original post by Super199)
    Is there a reason to why it gets partially delocalised in the ring?
    Yes, it can.

    The nitrogen can adopt sp2 hybridisation as it is bonded to only three other atoms, leaving its lone pair in a 'p' orbital parallel to the pi system of the ring.

    The further delocalisation of the electrons spreads charge and stabilises the molecule overall.
 
 
 

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