absramarao
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methoxylation of hydroxyl group in Paracetamol-help needed for the parameters
IS it possible to prepare para methoxy acetanilide by methoxylating paracetamol without the danger of deacetalation?
Could you please suggest any method using Dimethyl sulphate?
-thanks& Regards
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SecretSquirrel
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I think you can safely alkylate the para hydroxyl group without destroying the acetylamino group.
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absramarao
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Is it possible to do it in aqueous medium?
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Nicodem
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https://sciencemadness.org/talk/viewthread.php?tid=8318
(Next time UTFSE before posting questions that are likely to have been answered already!)
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absramarao
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Thank you very much Mr.Nicodem.
In the thread, it says some where, that we should not use more NaOH. OK I shall try that in aqueous medium.
I could not get any hold on the following. ref given in the thread.Particularly the first one is of interest to me.
Can any one please get me the translated version of the paper in the reference cited?
""""Anyway, here are the references for the O-methylation of acetaminophen (I hope you read Chinese):
* Zhongguo Yiyao Gongye Zazhi, 34(2), (2003) 60-61. (dimethyl sulfate with NaOH/H2O; 50min/RT; 97% yield)
* Xuzhou Shifan Daxue Xuebao, Ziran Kexueban, 20(4) (2002) 68-70. (same method as above)
* Indian Journal of Chemistry, Section B: Organic Chemistry Including Medicinal Chemistry, 25B(12) (1986) 1258. (MeI/NaOEt/EtOH; 92% yield)
* Journal of Labelled Compounds and Radiopharmaceuticals, 19(3) (1982) 321-329. (CD3I with NaH/DMSO)"""
Thanks & regards
Ramarao
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Nicodem
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"Zhongguo Yiyao Gongye Zazhi" means "Journal of Chinese Medical Industry", but unless you read Chinese I really see no point in asking for that paper
(if available online at all!). Besides the method apears to be the standard one for methylations of phenols with dimethyl sulfate in aquoeus NaOH as
outlined in Organikum (which is available also as an e-book, just search for it).
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absramarao
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Thanks fro your info.
I could get the info on melting point of methoxy acetanilide.
I shall try a small batch.
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