gypsyNo2
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Purification of Carboxylic Acids (Knoevenagel)
Hey Guys,
Am working on something at the moment and I am using a slightly modified Knoevenagel condensation to give me aromatic, alpha, beta unsaturated
carboxcylic acids (http://dx.doi.org/10.1080/17518250802141200) and am having trouble purifying them.
I am reactting (all in molar eq) piperonal, malonic acid, ammonium formate in pyridine. Microwaved at 300W for about 2 minutes.
Have tried acid/base extraction but I keep getting this ultra fine powder which is hard to filer. have also tried simply washing the reaction contents
with water but nothing seems to give me a decent looking compound (impurities galore).
Any ideas ?
Cheers
GypsyNo2
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Hexavalent
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Have you tried looking for a suitable solvent and recrystallizing your compound slowly?
"Success is going from failure to failure without loss of enthusiasm." Winston Churchill
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gypsyNo2
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I have trialled a few, looks like DSMO/Water are a go but it tends to drop out as a powder which is just hard to deal with
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Hexavalent
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Sadly, that's the nature of some compounds.
You could also try cooling slowly in a gently warmed Thermos flask, or dissolve the compound into solvent and allow it to evaporate very slowly at RTP
or maybe in a dessicator.
"Success is going from failure to failure without loss of enthusiasm." Winston Churchill
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gypsyNo2
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Yeah cheers Hex, might give that a go, thanks mate.
Gyp
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Hexavalent
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You're welcome, give it a go and report back with your findings
"Success is going from failure to failure without loss of enthusiasm." Winston Churchill
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