Klute
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Are esters good solvants to conserve dry HCl?
Could small chaine aliphatic esters be good solvants to keep dry HCl gas for titration, as IPA? I know acetone, MEK, etc will self condense and can't
be conserved, but will esters react? If strictly anhydrous (over molecular seives, silica or other dessicants), no hydrolysis should accur..
I haven't seen any example of them be used for such titrations, but I haven't found any reasons why they couldn't be used... They are often used to
dissolve the base to be neutralised, with addition of HCl in IPA or such...
Also, I haven't found any data concerning the maxium amount of HCl gas they can absorb..
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guy
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| Quote: | Originally posted by Sheriff
When I synthesize NaOCO2 I distill the HCl I use from IPA to anh. If you keep it in the flask with a cork on it not much hydrolyis will occur. Better
keep it in the fridge as well to keep it cool because hydroysis occurs from the vapours which bring water vapour in contact with the HCl at room temp
from the air trapped in the container you are holding the HCl in. |
STOP GIVING STUPID ADVICE
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Klute
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euh... sorry? "STOP GIVING STUPID ADVICE"?
At which point did I give any advice? I ask a question...
Ok, I forgot to precise I was talking about AMINE bases...
And i DID precise that i was SUPPOSING that totally anhydrous esters ON SILICA OR MOL.SIEVES would not hydrolyse in presence of HCl...
BUT WHAT DO I KNOW that was exactly why i was ASKING A QUESTION and certainly not GIVING ADVICE on any NaOCO2 synthesis or whatever...
Chill out man, what's all that about?
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guy
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| Quote: | Originally posted by Klute
euh... sorry? "STOP GIVING STUPID ADVICE"?
At which point did I give any advice? I ask a question...
Ok, I forgot to precise I was talking about AMINE bases...
And i DID precise that i was SUPPOSING that totally anhydrous esters ON SILICA OR MOL.SIEVES would not hydrolyse in presence of HCl...
BUT WHAT DO I KNOW that was exactly why i was ASKING A QUESTION and certainly not GIVING ADVICE on any NaOCO2 synthesis or whatever...
Chill out man, what's all that about? |
I was talking to the Sheriff, but he deleted his post.
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unionised
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I think the simple answer is that unfortunately, given that ketones will react with HCl, it's fair to assume that esters will. The CH3CO- group
doesn't really know if it is connected to a CH3 as in acetone or a OC2H5 as in ethyl acetate. The reactions might be slower (and almost certainly more
complex) but they will still happen.
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Klute
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Sorry Guy! All my apologies, I didn't see Sheriff's post before he deleted it... I didn't understand the point of this quote at first  Sorry again...
And I guess you are right Unionised, I'll just stay with usual IPA, even though methyl/ethyl formate/acetate can be used to disslove the base in the
first place... Thanks for your answer!
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Ozone
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I hate to be the bearer of bad news, but the storage of HCl over an ester is a bad idea! If *any* water gets in there, the ester, surrounded by
catalyst, will cleave to yield the acid, alcohol, and will cost you some water.
Since the solubility of HCl at STP is around 36% w/w, this will do you no good (it (HClg) will escape).
No good can come of this,
O3
-Anyone who never made a mistake never tried anything new.
--Albert Einstein
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