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LiAlH4 help~

Discussion in 'DAT Discussions' started by joonkimdds, Dec 20, 2008.

  1. joonkimdds

    joonkimdds Senior Member
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    I believe that LiAlH4 can change
    aldehyde, COOH, ester into primary alcohol and
    ketone into 2ndary alcohol.

    Beside these, I don't understand what else it does.

    In roadmap2, there are two reactions that have LiAlH4 and they are none of what I wrote above.

    First one is...
    a ring-CH2N3 and the product is a ring-CH2-NH2.
    (I don't even know how N3 exist. is it CH2-N-N-N?)

    second one is
    a ring-NH-COCH3 and the product is a ring-NH-CH2-CH3.
     
  2. Danny289

    Danny289 Member
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    LiAlH4 is reduction agent, ask yourself what is the meaning of reduction? It means gaining "H" or loosing "O"( I don't go for gaining electron here) then you will find out what is going on.
     
  3. yankees27th

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    Hopefully this helps: http://upload.wikimedia.org/wikipedia/commons/3/30/LAH_rxns.png
    The N3 thing might be a typo. I've never seen that either. An N2 group is called a diazonium if I recall correctly...
    For the second example I'm pretty sure and ester would be reduced to an alcohol. That's what it shows on that link I put above at least...
     
  4. joonkimdds

    joonkimdds Senior Member
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    Thanks for the link :)
    by the way N3 is not a typo because your link shows it too :D
    So I guess I can just memorize N3 from your link.

    But I am still not sure what the 2nd example is.
    it's not in the link either.
     
  5. zuma35

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    Specifically for an amide, LAH reduces the carbonyl to a CH2.
     
  6. vhlam

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  7. IdahoDoc

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    The N3 is drawn out like this

    N=N=N and there are charges obviously it is really only used to then be reduced to N=N and i believe it it is done with LiAlH4 in ET2O.
     

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