organosurf
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Reductions with Aluminum / NaOH ?
Aluminum in aqueous NaOH reacts vigorously and is very exothermic, liberating hydrogen gas.
Final product is highly alkaline. Can this be used in place of aluminum amalgam reductions for basic or neutral reactants for metal surface mediated
hydrogenations ?
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thesmug
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May I ask why you need aluminum amalgam?
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organosurf
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I DONT need aluminum amalgam. If you read my post carefully, I wanted to know if there is a green alternative for reductions, a SUBSTITUTE for toxic
aluminum amalgam reductions which the university teaching sites on the web mention in their examples on metal mediated reductions.
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thesmug
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What I am asking is what are you doing that would otherwise require aluminum amalgam?
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Nicodem
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Thread Moved
4-3-2014 at 09:22 |
turd
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Quote: Originally posted by organosurf  | | Can this be used in place of aluminum amalgam reductions for basic or neutral reactants for metal surface mediated hydrogenations ?
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No - this has been asked many times before and the answer is still - no.
| Quote: | | What I am asking is what are you doing that would otherwise require aluminum amalgam? |
If you have nothing to contribute, simply don't post.
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Theoretic
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Gallium can be used in place of mercury: http://news.uns.purdue.edu/x/2007a/070515WoodallHydrogen.htm...
As far as the hydrogenations are concerned, there are quite a few catalytic H2-using protocols, with new ones appearing all the time. So many such
reactions don't need dissolving metal.
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papaya
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I must add that once I managed to obtain isopropanol from acetone by Al/NaOH reduction in water . The mixture was distilled afterwards and used to
prepare isopropyl nitrite (with low yield) just to prove that the alcohol really forms. I won't say it's effective since huge amounts of H2 is
liberated, but in desperate cases it may be useful.
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Mesa
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| Quote: Originally posted by turd |
| Quote: | | What I am asking is what are you doing that would otherwise require aluminum amalgam? |
If you have nothing to contribute, simply don't post. |
I don't understand how this is not a legitimate question. Activated aluminium reduces a pretty wide variety of functional groups, without knowing
what the starting compound/target compound is, it's difficult to give advice.
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Electra
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| Quote: Originally posted by Mesa | | Quote: Originally posted by turd |
| Quote: | | What I am asking is what are you doing that would otherwise require aluminum amalgam? |
If you have nothing to contribute, simply don't post. |
I don't understand how this is not a legitimate question. Activated aluminium reduces a pretty wide variety of functional groups, without knowing
what the starting compound/target compound is, it's difficult to give advice. |
I have to second Mesa here. Depending on the functional group, not all reduction methods are equal.
I don't even know why people do Aluminum Amalgams. So Messy, toxic, and so many other easier and clean ways to perform reductions.
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Mesa
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They are good for drying ethanol, or preparing aluminium isopropoxide, although neither of these are specifically redox's.
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