Sauron
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Indium Mediated Redn of Aryl Nitro to Amine
Here's an example of why and how some classical methods will persist
An Org.Syn procedure describes the "green" reduction of aromatic nitro compounds to corresponding amines with high selectivity in ethanol in presence
of NH4Cl.
This merely requires 10-fold excess of indium metal powder so I looked this stuff up, it is $25/g The example cited was about 10 g of p-nitroethyl
benzoate reduced by 24.7 g In powder.
The good news is that this $625 worth of catalyst is recoverable.
I think dissolving metal reductions will remain for a while...anyone want to rush out and order a Kg of Indium powder? That would be enough to reduce
a whole big 200 mmol of product.
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Fleaker
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Sauron, you needn't spend that much at all. There are methods that you can use to dissolve the indium and then precipitate it out. Don't even dare be
discouraged about that price. It's more like a dollar/gram for the metal (U2U if you want any), and I know you can make powder from it.
It would be difficult to ball mill though, even at cryogenic temperatures it is malleable.
Neither flask nor beaker.
"Kid, you don't even know just what you don't know. "
--The Dark Lord Sauron
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not_important
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I thought the purpose of indium based reductions was the selectivity, no sense using them when that wasn't required; the OrgSyn example was just that,
an example on a simple compound rather than a normal application. Or in cases where it gave some trick reaction that was handy.
At $25/g I should figure out how to powder the indium I have and sell it, I must be sitting on at least $50.000 worth of it 8-)
[Edited on 12-4-2007 by not_important]
Attachment: A Facile One-Pot Operations of Reduction and Allylation of Nitrobenzaldehydes Mediated by Indium.pdf (100kB) This file has been downloaded 597 times
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Sauron
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I do understand basic research.
This is just an example of economically egregious basic research.
Imagine if pd reductions required 10 eq rather than catalytic amounts.
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