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    Why is a tertiary halogenoalkane or a tertiary organic compound in general more reactive than their secondary and primary compounds? My friends or my teacher told me it's something about the carbocation stability of the compound being highter when an atom is being substituted by an attacking nucleophile.

    I don't quite understand how that is the case. Someone please explain plss



    thanks
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    (Original post by CookieHero)
    Why is a tertiary halogenoalkane or a tertiary organic compound in general more reactive than their secondary and primary compounds? My friends or my teacher told me it's something about the carbocation stability of the compound being highter when an atom is being substituted by an attacking nucleophile.

    I don't quite understand how that is the case. Someone please explain plss



    thanks
    In reactions with halogenoalkane, an intermediate forms known as a carbocation which is a hydrocarbon where one of the carbon atoms has 3 bonds instead of 4 leaving it with a +ve charge. The more stable this carbocation is the more reactive the halogenoalkane is and is more likely to form a product thats associated with the carbocation. The stability of a carbocation depends on how many carbon chains are bonded to the carbon with a +ve charge. Why is it more stable? You don't need to know but its due to the inductive effect of the carbon chains attached which push electrons towards the +ve carbon atom.
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    (Original post by Shiv is Light)
    In reactions with halogenoalkane, an intermediate forms known as a carbocation which is a hydrocarbon where one of the carbon atoms has 3 bonds instead of t leaving it with a +ve charge. The more stable this carbocation is the more reactive the halogenoalkane is and is more likely to form a product thats associated with the carbocation. The stability of a carbocation depends on how many carbon chains are bonded to the carbon with a +ve charge. Why is it more stable? You don't need to know but its due to the inductive effect of the carbon chains attached which push electrons towards the +ve carbon atom.
    It makes sense now thanks
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    (Original post by CookieHero)
    It makes sense now thanks
    Can i have some rep.. please
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    (Original post by Shiv is Light)
    Can i have some rep.. please
    Im new to these things but do I click the thumbs up?
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    (Original post by CookieHero)
    Im new to these things but do I click the thumbs up?
    yep but you can only rep someone once in like 12 hours
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    oh ic :P
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    (Original post by CookieHero)
    Why is a tertiary halogenoalkane or a tertiary organic compound in general more reactive than their secondary and primary compounds? My friends or my teacher told me it's something about the carbocation stability of the compound being highter when an atom is being substituted by an attacking nucleophile.

    I don't quite understand how that is the case. Someone please explain plss



    thanks
    As the number of alkyl groups on the base carbon increases so does the inductive effect of the alkyl groups attached (The "pushing" of electrons onto the base carbon) therefore the carbon will have more "electron pressure" on it - in this case the carbon has a halogen-carbon bond relieve some of this "electron pressure" by repelling the electron pair more onto the halogen. Making the carbocation more δ+ and therefore more likely to come under attack from nucleophiles.

    At AS you don't really need to know about alkyl group's inductive effect but you do at A2 when you start learning about lone pair availability and benzene rings. (I'm doing AS+A2 at the same time, which is somewhat useful as you can cement the AS theory with A2 knowledge )

    Further reading:
    http://www.chemguide.co.uk/mechanism...carbonium.html
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    (Original post by RME11)
    As the number of alkyl groups on the base carbon increases so does the inductive effect of the alkyl groups attached (The "pushing" of electrons onto the base carbon) therefore the carbon will have more "electron pressure" on it - in this case the carbon has a halogen-carbon bond relieve some of this "electron pressure" by repelling the electron pair more onto the halogen. Making the carbocation more δ+ and therefore more likely to come under attack from nucleophiles.

    At AS you don't really need to know about alkyl group's inductive effect but you do at A2 when you start learning about lone pair availability and benzene rings. (I'm doing AS+A2 at the same time, which is somewhat useful as you can cement the AS theory with A2 knowledge )

    Further reading:
    http://www.chemguide.co.uk/mechanism...carbonium.html
    Very interesting. I might actually try to do A2 at the same time with physics and maths.
 
 
 
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