Chemical Forums
Chemistry Forums for Students => Organic Chemistry Forum => Topic started by: spirit32 on June 09, 2011, 04:02:05 AM
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Hello everybody
I'm new to this forum, Does anybody know whether hydroquinone is soluble in dichloromethane(methylenechloride) or not? I need to dissolve it in order to perform an estherification reaction with a carboxylic acid. I use DCC and DMAP as catalyst (something like that) according to papers But in practice I cannot dissolve HQ in CH2Cl2. I'm wondering that my reagents are faulty or that's it.
tnx in advance
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Via the Merck Index: "Sol in 14 parts water; freely sol in alcohol, ether, slightly in benzene. Its soln becomes brown in the air due to the oxidation; the oxidation is very rapid in presence of alkali. Keep well closed and protected from light"
I'd try ether or THF first, DMF second.
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Via the Merck Index: "Sol in 14 parts water; freely sol in alcohol, ether, slightly in benzene. Its soln becomes brown in the air due to the oxidation; the oxidation is very rapid in presence of alkali. Keep well closed and protected from light"
I'd try ether or THF first, DMF second.
Thanks for your rep buddy
But according to manuscript i should dissolve! HQ in Dichloromethane. i tried but it didn't happen. I was suspicious of HQ transformed to quinone (oxidized), But i gained some new and the result was same. now I think maybe the wrong is with manuscript and description is incomplete. is it possible to use co-solvent?
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Okay, it didn't dissolve, but did the reaction go? If it isn't completely insoluble, the reaction will be slower, but it can still work. What happened?
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But according to manuscript i should dissolve!
People make mistakes in recording their procedures. Unless you got it from Organic Syntheses, I doubt anyone checked the procedure. Fortunately DCC DMAP is a pretty robust system. As long as the solvent won't harm the other components of the reaction, I wouldn't sweat it.
And as orgopete suggests, maybe its sparingly soluble in DCM which would allow it to react. This could be an advantage as it might slow oxidation of the solution. Have you tried to do the procedure as it was written?
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Thanks for your help
Since, during procedure urea is precipitated I suppose HQ should be solved but maybe the mechanism is the same witch you suggested! the reaction proceed via the tiny amount of HQ dissolved in DCM. I should try it again but my other reactant is limiting and expensive; it's hard to try various ways I'm a confused but i should try the suggested route by manuscript! then see what comes up next
thnak u again
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Another question!
Is dicyclohexylurea soluble in isopropanol? it's the bi-product of steglich esterification! I need to know how's the solubility of DCU?
tnx in advance
http://www.organic-chemistry.org/namedreactions/steglich-esterification.shtm (http://www.organic-chemistry.org/namedreactions/steglich-esterification.shtm)