nitro-genes
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acetoxy-methoxy exchange from acetylsalicylic acid? [edit]
There is no short question thread in this section and I'm to dumb to figure it out so I'll just post it here:
Would it be possible to produce an anisole from acetylsalicylic acid by boiling with 1 or 2 mole eqvts of sodium methoxide or anhydrous methylsulfuric
acid in absolute (m)ethanol? Would the carboxyl interfere or does it react completely different?
Seen how stable anisoles are to hydrolysis compared to acetyl salicylic, it might be favorable
[Edited on 6-11-2016 by nitro-genes]
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Crowfjord
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Anisole can indeed be made from aspirin, but the way you propose wouldn't get you there. That might get you a little methyl salicylate.
You can get there by hydrolyzing to salicylic acid, decarboxylating that to phenol, then methylating the phenol. The first two reactions are detailed
on this forum. Methylation can be done with base and any of a number of reagents like methyl bromide, methyl iodide, dimethyl sulfate, etc.
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nitro-genes
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Of course decarboxylation wouldn't occur spontaneously, I edited the title since this is indeed not direclty apprent, though I was wondering whether
the acetoxy group might exchange for a methoxy group, catalyzed by an acid or base. Sort of a transetherification reaction producing 2-methoxy benzoic
acid. Methylation of phenol can indeed be done by Williamson ether synthesis using methyl iodide/bromide and base, though I don't have the time,
equipment and experience to make/handle these compounds. Besides, the iodides to produce the iodine are not completely OTC, so I was reasoning more
from an OTC and simplicity perspective where generally available acetylsalicylic acid could possibly produce 2-methoxy benzoic acid instead with only
few steps and non-toxic reactants.
[Edited on 6-11-2016 by nitro-genes]
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Nicodem
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Thread Moved
6-11-2016 at 14:05 |
myristicinaldehyde
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Mood: сорок пять
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The problem with your scheme is that anisole is an ether, not a ester! You can't exchange the entire acetoxy for a methoxy: think of the acetoxy as an
ester of phenol and acetic acid (ethanoic acid).
I found some links and papers for you to enjoy:
http://www.organic-chemistry.org/synthesis/C1O/esters/transe...
http://www.sciencedirect.com/science/article/pii/S0040402001...
Attachment: Transesterification kinetics of phenyl salicylate 1.pdf (463kB)
This file has been downloaded 287 times
Attachment: Transesterification kinetics of phenyl salicylate 2.pdf (953kB)
This file has been downloaded 300 times
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