Pumukli
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Salicylic acid methylation?
I've been wondering how easy was the methylation reaction of salicylic acid?
No, not the esterification of the carboxyl group but the ether formation of the hydroxyl (to yield o-anisic acid in the end).
I could find dozens of descriptions and lab manuals where the synthesis of the "oil of wintergreen" was described but not the other.
Am I doing something wrong or do I overlook something obvious why the o-anisic acid synth could not be performed the way I want it?
Is it a bit more complicated than "dissolve the salicylic acid in some excess NaOH solution, stirr vigorously, add some dimethyl-sulfate in excess,
stirr for a while, get rid of unreacted methylating agent, enjoy your o-anisic acid"?
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dawt
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Quote: Originally posted by Pumukli  | | Is it a bit more complicated than "dissolve the salicylic acid in some excess NaOH solution, stirr vigorously, add some dimethyl-sulfate in excess,
stirr for a while, get rid of unreacted methylating agent, enjoy your o-anisic acid"? |
Well, that's how you get methyl o-methoxybenzoate: http://www.jocpr.com/articles/a-simple-and-one-step-commerci...
| Quote: |
Salicylic acid 200 g and potassium carbonate 415.6 g were charged in Acetone 1000 mL and Dimethyl sulfate 403 g was added slowly at 25-30°C. The
reaction was maintained at 55-60°C for 3-4 hrs and reaction progress was monitored by TLC. The reaction mixture was cooled to 25-30°C and filtered
remove salts. The resulting filtrate concentrated under vacuum to obtained 2-Methoxy-benzoic acid methyl ester. |
Saponificate that and you end up with your target compound.
Attachment: a-simple-and-one-step-commercially-cost-effective-process-for-eluxadoline-intermediates.pdf (223kB)
This file has been downloaded 313 times
[Edited on 2020-5-24 by dawt]
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Pumukli
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Thanks dawt!
So it seems it can be done.
Maybe the ester would be OK too.
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DraconicAcid
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I was similarly wondering if methyl salicylate could be deprotonated (and then alkylated) without hydrolyzing the ester.
Please remember: "Filtrate" is not a verb.
Write up your lab reports the way your instructor wants them, not the way your ex-instructor wants them.
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