chemrox
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K-formate
I need a supply of potassium formate to use as a proton source for a catalytic hydrogenation (STP conditions). I have the acid and KOH so do I simply
make a strong KOH solution, say 6M? and mix the appropriate amount of acid with it? Collect and dry the Crx? Re-crx from EtOH? This seems right but is
there a subtlety I have forgotten (or never knew?)
Thanks,
CRX
"When you let the dumbasses vote you end up with populism followed by autocracy and getting back is a bitch." Plato (sort of)
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blogfast25
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You may want to check the solubility of K formate and see if you can take advantage of it, crystallisation wise, in particular solubility/temperature
dependency.
[Edited on 11-11-2014 by blogfast25]
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HgDinis25
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Potassium Formate is Deliquescent. If water free product is important I would recomend washing your recristalization product from Ethanol with Ether.
Quickly dry the Ether away (easy task) and store away from air and humidity.
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chemrox
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I'm going to have to start over.. some procedures do it in-situ however the yield of formate is the issue. 30-40% (sorry didn't copy the whole cite).
A more efficient method using gaseous formaldehyde and KOH. Seems like a hassle for an intermediate. Especially since the reagent is needed in 2X
quantity. TCI might have it. Can't find any on ebay this week. An in-situ method offered by a member uses in situ but the eqs are confusing as the KOH
is also used to liberate an amide.hcl so there's KCl to filter out and some leftover KOH to account for. pH will be watched of course. Maybe pH is the
key for this hydrodehalogenation. My previously made KOH is mix of KOH (deliquescent) and K salts. Dead bugs too..
"When you let the dumbasses vote you end up with populism followed by autocracy and getting back is a bitch." Plato (sort of)
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