querjek
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Propionic Acid through MEK haloform?
Could I prepare propionic acid in decent yield from the haloform reaction with methyl ethyl ketone? I know textbook reactions but never know whether
they're actually practical to use or not.
EDIT: Probably should specify, with calcium hypochlorite powder and water
[Edited on 31-5-2009 by querjek]
it's all about chemistry.
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panziandi
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Not really in practice. The reaction is quite exothermic and on scale up is prone to run away. Not to mention on even modest scale up it is bucket
chemitsry due to the sheer volumes involved. Its nice in theory. In practice I'd say look at alkaline permanganate oxidation which, IIRC oxidises
methyl ketones to formic acid (and then to carbonate) and the potassium salt of the R-carboxylic acid.
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entropy51
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There is some discussion of propionate via haloform in this thread https://www.sciencemadness.org/whisper/viewthread.php?tid=10...
where Woelen has given the outline of a prep.
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S.C. Wack
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A couple hundred grams is not a daunting chore, many small reactions typical of chloroform preparations in books can be completed fairly quickly,
combined, and extracted. If you also have a use for the chloroform too then why not.
I did many experiments to try to improve upon written methods, trying to use the exotherm to advantage, but never had enough sense to use an
antifoaming agent. That really would have helped. I might try this with simethicone or something sometime.
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kclo4
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Quote: Originally posted by panziandi  | | Not really in practice. The reaction is quite exothermic and on scale up is prone to run away. Not to mention on even modest scale up it is bucket
chemitsry due to the sheer volumes involved. Its nice in theory. In practice I'd say look at alkaline permanganate oxidation which, IIRC oxidises
methyl ketones to formic acid (and then to carbonate) and the potassium salt of the R-carboxylic acid. |
Can you find a reference to that? I haven't been able to find a decent one, but I am really interesting in making propionic acid via MEK and KMnO4.
Expo cleaner used for dry erase markers contain an ether/ester of N-propanol IIRC. This could probably be oxidized to the acid.
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