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CuReUS
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ok ok ,maybe Al cannot be used.but now you agree that the reaction is not impossible.
amides can be reduced by reagents other than hydrides .
actually I always had this doubt.Why can't Al be used in the place of Zn.If you see the electrochemical series,Al is below Zn.doesn't that mean Al is
a better reducing agent than Zn ?
i found a good thread on Al/Hg
http://www.sciencemadness.org/talk/viewthread.php?tid=12514
[Edited on 15-5-2015 by CuReUS]
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Luderlasse
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Could you give more details about that book?
Are there an experimental section on that reduction?
Thanks
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Chemosynthesis
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Shame how it seems inaccessible to many, and the synthesis per FR1515582A is rather unappealing from a hobbyist standpoint.
You're being silly. If Al can't be used, the reaction using aluminum hasn't been shown to be possible in a lab. Sometimes using a transition metal
with a lower reduction potential actually alters your reaction rather than yield, as I implicated in an indole ring closure discussion previously.
Primary literature is invaluable, so I have to yet again recommend you use it when speculating. As far as the book goes, it's either Organic
Reactions: Mechanisms with Problems by Tyagi, page 26 or Organic Name Reactions Reagents and Molecular Rearrangements by Raj page A-25. Neither appear
to give citations for this transformation, though if I missed it, I would appreciate seeing it.
The source you quote appears to be using a Clemmenson reduction. Given I can't find a literature citation of this, the importance of which I have
stressed to you in the past, I have to assume this is a textbook error. These things, sadly, happen. Helv. Chim Acta (1952), 35, pp1577 follows a
similar scheme with LAH. Even assuming this Clemmenson is a valid scheme, not only is it useless without experimental conditions, but note how the
example is a primary amide. Here is an example of what I can only presume to be similar conditions (without a methodology) leaving secondary and
tertiary amides untouched in a molecule: J Antibiot (Tokyo) 1987 Jan;40(1):14–21. See pages 14 section "chemistry" near the bottom and the scheme on
15 for summary.
Find actual peer-reviewed experimentals of a secondary amide if you like.
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CuReUS
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| Quote: | | You're being silly. If Al can't be used, the reaction using aluminum hasn't been shown to be possible in a lab. |
no no,I didn't mean that using Al was possible,I meant that amides could be reduced by other reagents,other than borohydrides.everyone seems to think
that any other way is impossible
| Quote: | | As far as the book goes, it's either Organic Reactions: Mechanisms with Problems by Tyagi, page 26 or Organic Name Reactions Reagents and Molecular
Rearrangements by Raj page A-25. |
yes,you are correct,its from the organic name reactions,reagents and molecular rearrangements.I found it from google books
| Quote: | | Neither appear to give citations for this transformation |
that's the exact problem I faced,even after searching so much,i couldn't find any reference.but why will someone make it up just like that ? If its an
error,what do you think should be the correction.The scheme itself is dubious,do we have to pass H2 or is that [H] referring to nascent
Hydrogen formed by the action of acid on metal ?
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Chemosynthesis
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I would expect that it was an editing error and that LAH would be the correct reagent.
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karlos³
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Here look on page 166, it starts at the bottom of this page:
This will clear everything up you are saying CuReUS 
Kindest Regards
Attachment: reductions in o-chem.pdf (4MB)
This file has been downloaded 556 times
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CuReUS
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I quickly glanced over the pdf(which I already have) and the only thing I found was that sodium and sodium amalgam reduce amides but in very low
yields
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