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    My synthesis went CH4->CH3Cl->CH3CN->CH3CH2CN

    http://puu.sh/1I6HL

    http://puu.sh/1I6I8

    I used HCN - it says HCN is not allowed and KCN must be used, can someone explain why?

    I also used Sn/HCl is incorrect as it forms a Ketone, I was never taught how these two work, I was just told to use them. Could someone please explain?
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    (Original post by Hormonal)
    My synthesis went CH4->CH3Cl->CH3CN->CH3CH2CN

    http://puu.sh/1I6HL

    http://puu.sh/1I6I8

    I used HCN - it says HCN is not allowed and KCN must be used, can someone explain why?

    I also used Sn/HCl is incorrect as it forms a Ketone, I was never taught how these two work, I was just told to use them. Could someone please explain?
    HCN is an incredibly toxic gas. KCN is as toxic but due to the fact it is a solid it is much, much easier to handle. You also need the cyanide anion, which is easily present in KCN, whereas HCN is only weakly acidic so you don't get as much CN-.

    The Sn/HCl reduction is university level. The Sn donates one electon at a time (initially forming a radical), reducing the CN to an imine (C=N), which is then hydrolysed by the acid to form the carbonyl.
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    (Original post by illusionz)
    HCN is an incredibly toxic gas. KCN is as toxic but due to the fact it is a solid it is much, much easier to handle. You also need the cyanide anion, which is easily present in KCN, whereas HCN is only weakly acidic so you don't get as much CN-.

    The Sn/HCl reduction is university level. The Sn donates one electon at a time (initially forming a radical), reducing the CN to an imine (C=N), which is then hydrolysed by the acid to form the carbonyl.
    The thing is, normally we've been allowed HCN :/

    If asked the same question, shall I always say Ni/H2 and KCN?
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    (Original post by Hormonal)
    The thing is, normally we've been allowed HCN :/

    If asked the same question, shall I always say Ni/H2 and KCN?
    I'm surprised you've been allowed HCN, but I'd always say KCN in future.

    As for reduction of nitriles to amines, either catalytic hydrogenation (Ni/H2), or reduction with LiAlH4 will be fine. I prefer LiAlH4 as when it comes to catalytic hydrogenations, different metals are used for different reagents, so I find it easier to just remember LiAlH4.
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    (Original post by illusionz)
    I'm surprised you've been allowed HCN, but I'd always say KCN in future.

    As for reduction of nitriles to amines, either catalytic hydrogenation (Ni/H2), or reduction with LiAlH4 will be fine. I prefer LiAlH4 as when it comes to catalytic hydrogenations, different metals are used for different reagents, so I find it easier to just remember LiAlH4.
    Thank you very much, KCN it is!

    I'll only use HCN to form hydroxynitriles now >.>
 
 
 
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