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    Hi all, long shot, but could someone explain the reaction mechanism for the reduction of a Nitrile (C triple bond to N) to a primary amine, please?

    the only two reagents are the nitrile and LiAlH4. I know the first step- Hydride attacks at carbon, electron pair from triple bond moves to nitrogen- but after that i'm stumped.

    Cheers
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    (Original post by hai2410)
    Hi all, long shot, but could someone explain the reaction mechanism for the reduction of a Nitrile (C triple bond to N) to a primary amine, please?

    the only two reagents are the nitrile and LiAlH4. I know the first step- Hydride attacks at carbon, electron pair from triple bond moves to nitrogen- but after that i'm stumped.

    Cheers
    After that, it's reasonable to say that the nitrogen-based anion would attack the AlH3, giving an aluminium-based anion. Then you can attack with another hydride, or go intramolecular. There aren't any available protons in the solvent (which is usually polar but aprotic, so ether or THF), so you only obtain the amine when you do the aqueous quench.
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    Catalytic hydrogenation with Ni/H2 is perfectly acceptable.

    CH3CN + 2H2 ---> CH3CH2NH2



    Edit: Don't know the mechanism (A-level student), we only had to learn the reaction and re-agents/conditions. Sorry.
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    (Original post by hai2410)
    Hi all, long shot, but could someone explain the reaction mechanism for the reduction of a Nitrile (C triple bond to N) to a primary amine, please?

    the only two reagents are the nitrile and LiAlH4. I know the first step- Hydride attacks at carbon, electron pair from triple bond moves to nitrogen- but after that i'm stumped.

    Cheers
    www.ulm.edu/~junk/examkeys/pp232_7_ch20.ppt

    http://www.cem.msu.edu/~reusch/VirtualText/crbacid2.htm
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    (Original post by hai2410)
    Hi all, long shot, but could someone explain the reaction mechanism for the reduction of a Nitrile (C triple bond to N) to a primary amine, please?

    the only two reagents are the nitrile and LiAlH4. I know the first step- Hydride attacks at carbon, electron pair from triple bond moves to nitrogen- but after that i'm stumped.

    Cheers
    Is this for that organic workshop thing? Looked mean that they set it...
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    (Original post by Kyle_S-C)
    Is this for that organic workshop thing? Looked mean that they set it...
    Given the sig, I'd guess at it being a first year tute sheet

    ... although quite what Ed would say about the OP asking for help on the internet, who can say...
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    Sorry totally forgot about this thread. I ended up going with the lone pair proceeding to attack into the empty AlH3 p orbital and so on. And was no aqeous quench step which was part of the confusion but w/e. Won't deny it was a question sheet
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    Chemistry experiment F, Lent term right? I'm a first year who's just been set this question sheet too haha.
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    Me three! Thanks for the help up there!
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    Me four, cheers guys
 
 
 
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