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    Can someone explain the bit I have put in black.

    I thought LiAlH4 was a reducing agent for aldehydes/ketones to alcohol.
    What is it acting as here?
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    The hydrides are attacking the nitrile carbon (CN). The lone pairs on the nitrogen/ electrons from the triple bond coordinate to the aluminium, which then kicks out a hydride which attacks the nitrile carbon, giving you a C=N-AlH3 species. The AlH3 then loses another hydride which again attacks the nitrile carbon, pushing electrons from the double bond onto the nitrogen giving you a C-N(-)-AlH2 species. An aqueous work up will then protonate the nitrile, kicking out the aluminium which results in C-NH2 and an aluminium salt which can be washed away.
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    (Original post by Super199)
    Can someone explain the bit I have put in black.

    I thought LiAlH4 was a reducing agent for aldehydes/ketones to alcohol.
    What is it acting as here?
    Thats NaBH4 your on about (ketones/aldehydes --> alcohols)

    LiAlH4/ H2+Nickel Catalyst / Tin + HCl are reducing agents CN --> CNH2
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    (Original post by Sniperdon227)
    Thats NaBH4 your on about (ketones/aldehydes --> alcohols)

    LiAlH4/ H2+Nickel Catalyst / Tin + HCl are reducing agents CN --> CNH2
    LiAlH4 is just a stronger reducing agent, it will do the exact same as sodium borohydride to aldehydes/ketones.
 
 
 
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