mbrown3391
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Acetic anhydride
Im trying to synthesize acetic anhydride, and i read something on wikipedia about the condensation reaction of acetic acid forming it. Any idea what
catylist would used for this? Also, any other methods of production would be appreciated. I know you can make it by the reaction of acetyl chloride
and sodium acetate. Sodium acetate is obviously not a problem, but so far the only synths for acetyl chloride that ive read of involve hard to find
chemicals like various phosphorous compounds and Thionyl chloride. Are there any more common chemicals that can be used to synthesize Acetyl chloride
from acetic acid?
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Ozone
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No. So far as I know, acyl chlorides are impossible to make with "more common chemicals".
Please use the search engine, above and left, just under the Sciencemadness symbol. There is a ton of stuff on this subject.
alternatively, UTFSE.
Best,
O3
-Anyone who never made a mistake never tried anything new.
--Albert Einstein
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Sauron
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There are threads on making acetic anhydride, and there are threads on making acetyl chloride and other lower acy chlorides notably propionyl
chloride. Brother Ozone is correct that no additional thread is really required as even if someone comes up with something new it can be added to one
or more of the existing threads profitably.
If you would like an encapsulation of the main conslusions I have come to on this subject feel free to PM me and I will expound.
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mbrown3391
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Ive found two promising options-- the reaction of acetylene and acetic acid, and the reaction of acetaldehyde and sodium acetate. Any idea what
catylists, if any, would be used in these reactions?
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Eclectic
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Google "acetylene acetic site:sciencemadness.org"
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chemkid
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On the organic chemistry section there is a thread
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Sauron
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The much more likely preparations are from acetyl chloride and anhydrous sodium acetate.
And there are two maybe three really reliable methods of [preparing the requisite acetyl chloride.
1. Benzoyl chloride and acetic acid per H.C.Brown in JACS, available on this site
2. TCT (cyanuric chloride) and acetic acid, by several methods all referenced from this site
3. Phthaloyl chloride and acetic acid. Article by Kyrides, JACS, available from this site. As phthaloyl chloride is more expensive than benzoyl
chloride, this is a secondary choice, although you can equalize the cost somewhat by preparing the phthaloyl chloride from benzotrichloride and
phthalic anhydride.
Note that either acetyl chloride or acetic anhydride itself can be prepared from oxalyl chloride, and oxalyl chloride can be made from oxalic acid and
TCT.
I do not recommend thionyl chloride, nor any of the phosphorus halides for this purpose. I also do not recommend the ketene method as it is slow and
extremely hazardous.
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vulture
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We have a HUGE thread on this. Don't be so fucking lazy.
Closed.
One shouldn't accept or resort to the mutilation of science to appease the mentally impaired.
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