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zed
International Hazard
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Registered: 6-9-2008
Location: Great State of Jefferson, City of Portland
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Mood: Semi-repentant Sith Lord
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As stated previously. Under some circumstances a protecting group is not required.
The molecule you are trying to synthesize bears some structural similarity to Codeine, and Chemists did spend many years perfecting that synthesis via
the etherization of Morphine.
Eventually, they simply utilized a Quaternary Ammonium Salt, as the Methylating agent. Such a reagent will preferentially Methylate the hydroxy
group.
https://www.unodc.org/unodc/en/data-and-analysis/bulletin/bu...
I'll dig a little bit more. Yeah, I'm imagining Ethylation is not more difficult than Methylation, but I do not have a procedure.
The Ethyl Ether of Morphine (an analog to Codeine) is named Dionine. It is particularly useful for application to the eyes.
The preferred use of the Ethyl Ether rather than the Methyl Ether, might have to do with the toxic effect Methanol has on the optic nerve. I do not
know that with any certainty though.
Dionine/Ethyl Morphine synthesis.... https://www.sciencedirect.com/science/article/abs/pii/S00959...
Sorry. No can open it, myself!
[Edited on 31-7-2021 by zed]
[Edited on 31-7-2021 by zed]
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Triflic Acid
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Ethanol should work as a solvent. If you have more than one go at this, try both ways. The diethyl oxalate/carbonate way, and the protecting group +
EtBr way.
There wasn't a fire, we just had an uncontrolled rapid oxidation event at the power plant.
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njl
National Hazard
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Acetic acid catalyzed ester aminolysis
Reflux condenser?? I barely know her!
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Monoamine
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Quote: Originally posted by EverythingAl2O3  | | Is there anything stopping you from doing an acid catalyzed ether synthesis? So you could use H2SO4 and ethanol to get your phenoxy group and avoid
the overalkylation? |
I'm not too familiar with this approach, but if this works for armatic OH groups, then of course this would solve the problem. Let me look into the
exact reaction mechanism for this kind of ether-synthesis.
Thanks for the tip!
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Monoamine
Hazard to Others
Posts: 168
Registered: 25-5-2021
Location: Sweden(ish)
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Mood: +7
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| Quote: Originally posted by zed | As stated previously. Under some circumstances a protecting group is not required.
The molecule you are trying to synthesize bears some structural similarity to Codeine, and Chemists did spend many years perfecting that synthesis via
the etherization of Morphine.
Eventually, they simply utilized a Quaternary Ammonium Salt, as the Methylating agent. Such a reagent will preferentially Methylate the hydroxy
group.
https://www.unodc.org/unodc/en/data-and-analysis/bulletin/bu...
I'll dig a little bit more. Yeah, I'm imagining Ethylation is not more difficult than Methylation, but I do not have a procedure.
The Ethyl Ether of Morphine (an analog to Codeine) is named Dionine. It is particularly useful for application to the eyes.
The preferred use of the Ethyl Ether rather than the Methyl Ether, might have to do with the toxic effect Methanol has on the optic nerve. I do not
know that with any certainty though.
Dionine/Ethyl Morphine synthesis.... https://www.sciencedirect.com/science/article/abs/pii/S00959...
Sorry. No can open it, myself!
[Edited on 31-7-2021 by zed]
[Edited on 31-7-2021 by zed] |
Very interesting that it contains a similar 3D moiety as Codeine! Just looked up the structure and there really is a similar one, but smaller, than
that of the above compound. But as someone pointed out it also bears a semblance to noribogaine, the active metabolite of ibogaine, both of which are
used to cure opiate addiction. But I guess in retrospect it isn't a surprise that a medication that addresses the symptoms of opiate withdrawal would
have a similar structure to the later...
As for the difficulty of methylation vs. ethylation, I would actually imagine that ethylation is easier (if you're using an alkyl halide) since MeBr
is a gas while EtBr isn't, so it's much easier to control the amount of reagent introduced to the reaction. (I'd guess that more than one molar
equivalent of EtBr would inevitably lead to the formation of side products, where the amine is also alkylated).
Maybe you could use a tosylated methanol if you want to do a methylation? But honestly, I don't remember if that would even work for an ether
synthesis. I'll look into it.
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