From L-meth to D-meth

SoldadoDeDrogas

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azides

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Can anyone help me understand if it is possible to use generic nasal inhalers that contain "levmetamfetamine 50mg" to get to d-meth.
https://bbgate.com/threads/methamphetamine-synthesis-vicks-inhaler.4974/#post-46343 Will these instructions work in theory?
Or do I need to use the above racemization and resolution provided by Amphibian? Or 41Dxflatline, etc?
SoldadoDeDrogasWhile it would work... some of those chemicals are hard to get or might be dangerous like my username, instead you should use naproxen and use the pope-peachy with the NASID Naproxen. I have posted the full guide below
 
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azides

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I will definitely give it a shot. I am wondering if anyone has extracted the nasal inhalers containing "Levomefamfetamin 50mg" - what is the best process for doing this and does it crystallize like ice will? Or what can I expect the isolated product to look like?
SoldadoDeDrogasThe workup has been posted earlier but again

It is ....

Study of the mechanism of the optical resolution of N-methylamphetamine via diastereoisomeric salt formation by the Pope-Peachey resolution method as discussed by the retort later

https://sci-hub.wf/10.1016/s0957-4166(00)86170-4

https://www.sciencedirect.com/science/article/abs/pii/S0957416600861704


refences and Notes
I.) Newman,P. Optical Resolution Procedures for Chemical Compounds, vols.l-3, optical Resolution Informztion
Catre, Manhattan College, New York, 1978-84;

2.) Jacques,J.; Collet,A.; Wilen,SH. Enantiomers, Racemates and Resolutions, Wiley and Sons, New York,
1981,378.p.

3.) Fogassy,E.; hs,M.; Faigl,F ; Rohonczy,J, Ecsery,Z. J.Chem.Soc.Perkin Trans.2, 1986, 1881
4.) Pope,W.J.; Peachey,S.J. J.Chem.Soc.,1899,75,1066

5.) 7.84 g (0.0525 mol) racemic N-methylamphetamine and 9.73 g (0.0525 mol) racemic N-
methylamphetamine hydrochloride were dissolved in 70 ml of abs. ethanol and 7.91 g (0.0525 mol) R,R-
tartaxic acid in 56 ml of abs. ethanol. Both stock solutions were divided into fifteen portions by volume by a
burette and reacted at 22+1”C The mixtures were standii undisturbed for 15, 90 minutes and 5, 24, 1 IS
hours, than the precipitates were filtered and dried. From 0.4 g of each salt the base was liberated by ccNaOH
and extracted from the aqueous phase by dicblorometbane.
6.) All experiments were performed at the same work-bench at 2Ul’C room temperature. Stock solutions of
the racemate and the resolving agent were used to avoid the error of weight measurements. All the flasks used
had identical size and shape
7.)The tartrate and hydrochloride content of the salts were determined by potenciometry by a RADIOMETER-
85 TTT automatic titrator with 0.1 N NaOH and 0.1 N AgNO,.
8.) The specific rotations was measured by a Perkin Elmer 241 polarhneter. The specific rotation of the
optically pure R-N-methylamphetamine is [a]: - -18.90 (c 0.1, IN HCI).
9.) The salts were not washed at filtering. The small amount of hydrochloride found in the salts probably comes
from the mother liquor sticked and dried to the surface of the salt.
10.) This is in accordance with the results3, that the R-l II is the more stable salt than S-1.11

If you want more you could also read the retort below everything should be in the https://sci-hub.wf by in large though ;)

Instead in this twist , only half an equivalent of chiral amine is used. Half an equivalent of a cheaper, optically inactive amine base is used in its place. This not only makes the process cheaper, but results in a more dramatic difference in solubilities. The conjugate base of the desired (d)-(+)-enantiomer crystallizes out with the conjugate acid of the chiral amine, with high selectivity. This leaves the more soluble salt product of (l)-(-)-naproxen and the achiral amine behind in solution.
 
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azides

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The workup has been posted earlier but again

It is ....

Study of the mechanism of the optical resolution of N-methylamphetamine via diastereoisomeric salt formation by the Pope-Peachey resolution method as discussed by the retort later

https://sci-hub.wf/10.1016/s0957-4166(00)86170-4

https://www.sciencedirect.com/science/article/abs/pii/S0957416600861704


refences and Notes
I.) Newman,P. Optical Resolution Procedures for Chemical Compounds, vols.l-3, optical Resolution Informztion
Catre, Manhattan College, New York, 1978-84;

2.) Jacques,J.; Collet,A.; Wilen,SH. Enantiomers, Racemates and Resolutions, Wiley and Sons, New York,
1981,378.p.

3.) Fogassy,E.; hs,M.; Faigl,F ; Rohonczy,J, Ecsery,Z. J.Chem.Soc.Perkin Trans.2, 1986, 1881
4.) Pope,W.J.; Peachey,S.J. J.Chem.Soc.,1899,75,1066

5.) 7.84 g (0.0525 mol) racemic N-methylamphetamine and 9.73 g (0.0525 mol) racemic N-
methylamphetamine hydrochloride were dissolved in 70 ml of abs. ethanol and 7.91 g (0.0525 mol) R,R-
tartaxic acid in 56 ml of abs. ethanol. Both stock solutions were divided into fifteen portions by volume by a
burette and reacted at 22+1”C The mixtures were standii undisturbed for 15, 90 minutes and 5, 24, 1 IS
hours, than the precipitates were filtered and dried. From 0.4 g of each salt the base was liberated by ccNaOH
and extracted from the aqueous phase by dicblorometbane.
6.) All experiments were performed at the same work-bench at 2Ul’C room temperature. Stock solutions of
the racemate and the resolving agent were used to avoid the error of weight measurements. All the flasks used
had identical size and shape
7.)The tartrate and hydrochloride content of the salts were determined by potenciometry by a RADIOMETER-
85 TTT automatic titrator with 0.1 N NaOH and 0.1 N AgNO,.
8.) The specific rotations was measured by a Perkin Elmer 241 polarhneter. The specific rotation of the
optically pure R-N-methylamphetamine is [a]: - -18.90 (c 0.1, IN HCI).
9.) The salts were not washed at filtering. The small amount of hydrochloride found in the salts probably comes
from the mother liquor sticked and dried to the surface of the salt.
10.) This is in accordance with the results3, that the R-l II is the more stable salt than S-1.11

If you want more you could also read the retort below everything should be in the https://sci-hub.wf by in large though ;)

Instead in this twist , only half an equivalent of chiral amine is used. Half an equivalent of a cheaper, optically inactive amine base is used in its place. This not only makes the process cheaper, but results in a more dramatic difference in solubilities. The conjugate base of the desired (d)-(+)-enantiomer crystallizes out with the conjugate acid of the chiral amine, with high selectivity. This leaves the more soluble salt product of (l)-(-)-naproxen and the achiral amine behind in solution.
azidesI wont make it easy you will have to calculate your mols.
 

azides

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I will definitely give it a shot. I am wondering if anyone has extracted the nasal inhalers containing "Levomefamfetamin 50mg" - what is the best process for doing this and does it crystallize like ice will? Or what can I expect the isolated product to look like?
SoldadoDeDrogasYou will need lots of crystallizations for the sole fact that menthol and camphor will be in your product
 

btcboss2022

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I read this resolution in the past and is the only one that say that using RR tartaric(d-tartaric or L+tartaric) the R enantiomer of N-methylamphetamine remains in the solid.
I re-read it many times to understand why and I didn't understand yet, they can say what they want in that experiment but I can assure you and proof you that after hundreds of resolutions done, that R enantiomer of N-methylamphetamine using RR tartaric remains in the liquid that's a fact even this experiment.
 

azides

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I read this resolution in the past and is the only one that say that using RR tartaric(d-tartaric or L+tartaric) the R enantiomer of N-methylamphetamine remains in the solid.
I re-read it many times to understand why and I didn't understand yet, they can say what they want in that experiment but I can assure you and proof you that after hundreds of resolutions done, that R enantiomer of N-methylamphetamine using RR tartaric remains in the liquid that's a fact even this experiment.
btcboss2022You are miss the "twist" or the retort subbing naproxen instead I think? Insteadd of using -tartaric or L+tartaric use naproxen

This not only makes the process cheaper, but results in a more dramatic difference in solubilities. The conjugate base of the desired (d)-(+)-enantiomer crystallizes out with the conjugate acid of the chiral amine, with high selectivity.This leaves the more soluble salt product of (l)-(-)-naproxen and the achiral amine behind in solution.
 
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btcboss2022

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You are miss the "twist" or the retort subbing naproxen instead I think? Insteadd of using -tartaric or L+tartaric use naproxen

This not only makes the process cheaper, but results in a more dramatic difference in solubilities. The conjugate base of the desired (d)-(+)-enantiomer crystallizes out with the conjugate acid of the chiral amine, with high selectivity.This leaves the more soluble salt product of (l)-(-)-naproxen and the achiral amine behind in solution.
azidesI was just talking about the doc of the link that you sent not about naproxen process.
 

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It's all based on pope peachy... just variations nd that it can and has been used to racemic meth back from L
azidesIn my case is not about that I'm doing throw a more logic way we will see if I achieve it completely I have it partially at the moment.
Anyway here tested many acids even naproxen and seems that O,O'-dibenzoyltartaric acid works better( I don't use this one)
 

SoldadoDeDrogas

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Sorry I don't think I understood this completely. I am not trying to resolve racemic into d- and l- and seperate. I am trying to understand if it is possible to recycle l- into racemic. Which I am still confused about as I don't know if you made a typo. This work up speaks of charging with racemic meth and substituting tartaric with 1 part HCl and 1 part naproxen to seperate? Again, I am trying to understand if it was possible to turn the l- from nasal inhalers into racemic using a substitute for AIBN/Thiol. Please pardon my confusion. Thank you.
 
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Sorry I don't think I understood this completely. I am not trying to resolve racemic into d- and l- and seperate. I am trying to understand if it is possible to recycle l- into racemic. Which I am still confused about as I don't know if you made a typo. This work up speaks of charging with racemic meth and substituting tartaric with 1 part HCl and 1 part naproxen to seperate? Again, I am trying to understand if it was possible to turn the l- from nasal inhalers into racemic using a substitute for AIBN/Thiol. Please pardon my confusion. Thank you.
SoldadoDeDrogasHe said that just heating l isomer mixture from that method becomes racemic.
Im working in another option
 

azides

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Sorry I don't think I understood this completely. I am not trying to resolve racemic into d- and l- and seperate. I am trying to understand if it is possible to recycle l- into racemic. Which I am still confused about as I don't know if you made a typo. This work up speaks of charging with racemic meth and substituting tartaric with 1 part HCl and 1 part naproxen to seperate? Again, I am trying to understand if it was possible to turn the l- from nasal inhalers into racemic using a substitute for AIBN/Thiol. Please pardon my confusion. Thank you.
SoldadoDeDrogasThr comment below is correct. But you want to sub with the appropriate mols.
 

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Sorry I don't think I understood this completely. I am not trying to resolve racemic into d- and l- and seperate. I am trying to understand if it is possible to recycle l- into racemic. Which I am still confused about as I don't know if you made a typo. This work up speaks of charging with racemic meth and substituting tartaric with 1 part HCl and 1 part naproxen to seperate? Again, I am trying to understand if it was possible to turn the l- from nasal inhalers into racemic using a substitute for AIBN/Thiol. Please pardon my confusion. Thank you.
SoldadoDeDrogasI am trying to understand if it is possible to recycle l- into racemic


yes mate we have said this
It's called RRR resolved racemate and recycle Resolution OR

Resolution-Racemization-Recycle​


You seperate with naproxen vs L+tartaric

Heat liquor of L meth With naproxen and this converts to DL meth overtime.

Seperate again with naproxen

Reheat again to make DL

There is nothing more you need and everything is detailed in the report. Instead you sub naproxen in the molar ammounts in specification you will need to read both the retort and the original pope peachy to get the idea what to do


Resolution-Racemization-Recycle
It's pretty clear what to do. I'm sorry it isn't making sense to you because it's alreadly pretty clear what to do.

There was MORE then enough info here for any NEWBEE to get started.
 
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SoldadoDeDrogas

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Maybe if you copy paste it one more time, maybe I'll understand. Maybe you should be awarded a nobel peace prize for your amazing discovery, or maybe I should just save my money and not waste my time. Thanks tho.
 

azides

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Maybe if you copy paste it one more time, maybe I'll understand. Maybe you should be awarded a nobel peace prize for your amazing discovery, or maybe I should just save my money and not waste my time. Thanks tho.
SoldadoDeDrogas7.84 g (0.0525 mol) racemic N-methylamphetamine and 9.73 g (0.0525 mol) racemic N-
methylamphetamine hydrochloride were dissolved in 70 ml of abs. ethanol and 7.91 g (0.0525 mol) R,R-
tartaxic acid in 56 ml of abs. ethanol. Both stock solutions were divided into fifteen portions by volume by a
burette and reacted at 22+1”C The mixtures were standii undisturbed for 15, 90 minutes and 5, 24, 1 IS
hours, than the precipitates were filtered and dried. From 0.4 g of each salt the base was liberated by ccNaOH
and extracted from the aqueous phase by dicblorometbane.
6.) All experiments were performed at the same work-bench at 2Ul’C room temperature. Stock solutions of
the racemate and the resolving agent were used to avoid the error of weight measurements. All the flasks used
had identical size and shape
7.)The tartrate and hydrochloride content of the salts were determined by potenciometry by a RADIOMETER-
85 TTT automatic titrator with 0.1 N NaOH and 0.1 N AgNO,.
8.) The specific rotations was measured by a Perkin Elmer 241 polarhneter. The specific rotation of the
optically pure R-N-methylamphetamine is [a]: - -18.90 (c 0.1, IN HCI).
9.) The salts were not washed at filtering. The small amount of hydrochloride found in the salts probably comes
from the mother liquor sticked and dried to the surface of the salt.
10.) This is in accordance with the results3, that the R-l II is the more stable salt than S-1.11

If you want more you could also read the retort below everything should be in the https://sci-hub.wf by in large though ;)

Instead in this twist , only half an equivalent of chiral amine (naproxen) is used. Half an equivalent of a cheaper, optically inactive amine base is used in its place. This not only makes the process cheaper, but results in a more dramatic difference in solubilities. The conjugate base of the desired (d)-(+)-enantiomer crystallizes out with the conjugate acid of the chiral amine, with high selectivity. This leaves the more soluble salt product of (l)-(-)-naproxen and the achiral amine behind in solution
 

azides

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Maybe if you copy paste it one more time, maybe I'll understand. Maybe you should be awarded a nobel peace prize for your amazing discovery, or maybe I should just save my money and not waste my time. Thanks tho.
SoldadoDeDrogasInstead this naproxen research it was based on... nothing new just old stuff but put 2 and 2 and bingo was his nameo the ideal Pope-Peachy. This resolution may have practical application because the efficiency of the resolution is in the same range as with tartaric acid but only 0.25 molar equivalent of resolving agent is required for the resolution of 1 mol base. Chirality 11:373–375, 1999. © 1999 Wiley-Liss, Inc.

You would use between .5 to .25 less mol vs tartartic
 

SoldadoDeDrogas

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@azides I think you're having a hard time comprehending your own information, mine, or this thread in general. It's BS, this thread was dead some time ago, I don't know why you keep kicking it.
 

azides

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@azides I think you're having a hard time comprehending your own information, mine, or this thread in general. It's BS, this thread was dead some time ago, I don't know why you keep kicking it.
SoldadoDeDrogasWhat the issue mate.... ? even if In solution, the monosodium d-tartrate then preferentially forms a water-soluble salt with d-methamphetamine while the l-methamphetamine (still remaining in its freebase form) can be extracted with a non-polar solvent...

I think you have trouble understanding... it is indeed viable



https://www.reddit.com/r/TheeHive/comments/18ycbjh
1Azole
6 days ago

Naproxen would be an interesting reagent for chiral amine resolution

PsychedStrawberry
6 days ago

How come?



SunderedValley
6 days ago

It's been done before IIRC.
I speed read it pretty hard but the consensus seemed to be "works very well can sometimes be done even cheaper using other methods". Should be on either here, the drugnerds sub or Vespiary.


1Azole
6 days ago

Accessible, enantiomerically pure, useful carboxylic acid functionality, large pi system, aryl methoxy, all of these make it seem like a useful candidate with the last two descriptors being reasons it could be particularly interesting
 

SoldadoDeDrogas

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OK, I'm gonna PM you and we'll go forward OK? I've got everything I need to do this and nothing better to do, so let's see if I can be made into a believer also.
 
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azides

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OK, I'm gonna PM you and we'll go forward OK? I've got everything I need to do this and nothing better to do, so let's see if I can be made into a believer also.
SoldadoDeDrogasAfter talking with soldadoDeDrogas is not a new bee. But probably a learning larva. No offense we all started by in large from strikes TS2 books. (This is for everyone else) as he alreadly got the indepth talk.



Anyways when it comes to this reaction this can be rated semi easy to and understand from EASY to someone like me which is intermediate easy to hard for a new commer



This all steemed from a post.2 weeks ago







Notdrugs



A little while ago I heard that some labs were using Naproxen (like the NSAID) as the enantiopure acid. But I haven't been able to find any info at ALL on this method, so I really can't say with certianty



Me digging...





u/Notdrugs



Probably based on this retort? As I said earlier...The trick is to find the cheapest optically active acid that will bind to one isomer but not the other and which will change solubility sufficiently so that one of the products (be it the unreacted freebase or the reacted amide, sulfonate or whatever) can be washed into another solvent (one that is immiscible with the first solvent) so you end up with one isomer dissolved in the first solvent, the other isomer dissolved in the second solvent. Based on what this says what do you think.






Then not drugs response...





Notdrugs

• 13 days ago • Edited 13 days ago



That is really interesting! I can see how those caveats make commercial production much easier. It's not too often that we get "bulk production details" delineated in basic instruction, so thank you for that.



Later, this week

even if In solution, the monosodium d-tartrate then preferentially forms a water-soluble salt with d-methamphetamine while the l-methamphetamine (still remaining in its freebase form) can be extracted with a non-polar solvent...



I think you have trouble understanding... it is indeed viable






https://www.reddit.com/r/TheeHive/comments/18ycbjh
1Azole

• 6 days ago



Naproxen would be an interesting reagent for chiral amine resolution



PsychedStrawberry

• 6 days ago



How come?







SunderedValley

• 6 days ago



It's been done before IIRC.

I speed read it pretty hard but the consensus seemed to be "works very well can sometimes be done even cheaper using other methods". Should be on either here, the drugnerds sub or Vespiary.





1Azole

• 6 days ago



Accessible, enantiomerically pure, useful carboxylic acid functionality, large pi system, aryl methoxy, all of these make it seem like a useful candidate with the last two descriptors being reasons it could be particularly interesting



Then why my post is better



No I won't give details such as temp and time it's all in the ORIGINAL pope peachy.



No if you can get DCM benzene etc etc I'm not going to tell you an appropriate solvent to use as everything is USE THE FUCKING SEARCH ENGINE Google, here hive, etc...will have all the answers.



And no I won't calculate your moles. And if 1 more person who asks me specifics time etc...



They will be ignored everything is well documented



Again for everyone 1 more time



Notdrugs



A little while ago I heard that some labs were using Naproxen (like the NSAID) as the enantiopure acid. But I haven't been able to find any info at ALL on this method, so I really can't say with certianty



Me digging...





u/Notdrugs



Notdrugs



• 13 days ago • Edited 13 days ago







That is really interesting! I can see how those caveats make commercial production much easier. It's not too often that we get "bulk production details" delineated in basic instruction, so thank you for that.



again the theory of L VICKS to D meth . Is it POSSIBLE yes. Can someone who has not developed a mdma path not well documented do it, yes. Can someone asking if they can use 40% ethanol , DSMO vs DCM etc etc they aren't ready



Can you make MDA/MDMA from coffee/caffeic acid or similar... yes. Does 12% yeild to cost seem viable when piperonal acatate or other analogs are pennies on the $ and can make piperonal in 1-2 steps and from there safrole or isosafrole ... just because you can doesn't mean getting 10g of vicks inhalers will be "cost effective "

You might have to dig for anyone reading but anyone with an understanding of ts2 to make your OWN precoursers or pre-precursor this makes sense. If you followed it as a map and compass and not a recipe

While everyone wants its to be A+B + liquid + heat make chemical X and it works 0-80-95% of the time.

There a time you try and make cake but make bread.

Such as adding 1 to many carbons etc etc. Recrystalizations and separations of polymorphism or seperate entiomeners is an art in of itself.

Sadly my stuff is NOVEL MDMA and MDP2P production and less chiral resulation but I can read the pope peachy enough to stand by with 99% backing and if anyone wanna poke holes so be it. And I will talk but please no what solvent questions or calculations of mols everything is posted earlier and it is def viable
 

azides

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OK, I'm gonna PM you and we'll go forward OK? I've got everything I need to do this and nothing better to do, so let's see if I can be made into a believer also.
SoldadoDeDrogasAgain everything is posted everything is more viable then the AIBN posted earlier in a smaller setting.

But remember That is really interesting! I can see how those caveats make commercial production much easier. It's not too often that we get "bulk production details" delineated in basic instruction, so thank you for that.

You need bulk scale. Not 1.5g of vicks L. Using dirty or just crushed naproxen. Just buy the damn salt
 
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azides

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Enzymes as Resolving Agents
One class of enzymes that has received particular attention in this regard is the esterases,
which catalyze the hydrolysis of esters (Section 14.1C) to give an alcohol and a carbox-
ylic acid. We illustrate this method by describing the resolution of (R,S)-naproxen. The
ethyl esters of both (R)- and (S)-naproxen are solids with very low solubilities in water.
Chemists then use an esterase in alkaline solution to selectively hydrolyze the (S)-ester,
which goes into the aqueous solution as the sodium salt of the (S)-carboxylic acid. The
(R)-ester is unaffected by these conditions. Filtering the alkaline solution recovers the
crystals of the (R)-ester. After the crystals are removed, the alkaline solution is acidified
to precipitate pure (S)-naproxen. The recovered (R)-ester can be racemized (converted
to an R,S-mixture) and again treated with the esterase. Thus, by recycling the (R)-ester,
all the racemic ester is converted to (S)-naproxen



Elfspice incorrectly assumed that the NaOH was added to the solution to freebase the added amine hydrochloride. It is not. The freebase amine is to be used, and the purpose of the NaOH is to make the monosodium salt of the tartaric acid (which is a dicarboxylic acid).

In solution, the monosodium d-tartrate then preferentially forms a water-soluble salt with d-methamphetamine while the l-methamphetamine (still remaining in its freebase form) can be extracted with a non-polar solvent.

The reason all this happens is that because of the molecular shape of d-tartaric acid is such that in solution it fits better together with d-methamphetamine than with l-methamphetamine, given a choice (but will freely form a salt with both forms if enough acid is present, therefore one carboxylic acid group on each tartaric acid molecule is 'disabled' by the addition of one equivalent tof NaOH).

Instead in this case naproxen is used and should be solid I presume
 
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Enzymes as Resolving Agents
One class of enzymes that has received particular attention in this regard is the esterases,
which catalyze the hydrolysis of esters (Section 14.1C) to give an alcohol and a carbox-
ylic acid. We illustrate this method by describing the resolution of (R,S)-naproxen. The
ethyl esters of both (R)- and (S)-naproxen are solids with very low solubilities in water.
Chemists then use an esterase in alkaline solution to selectively hydrolyze the (S)-ester,
which goes into the aqueous solution as the sodium salt of the (S)-carboxylic acid. The
(R)-ester is unaffected by these conditions. Filtering the alkaline solution recovers the
crystals of the (R)-ester. After the crystals are removed, the alkaline solution is acidified
to precipitate pure (S)-naproxen. The recovered (R)-ester can be racemized (converted
to an R,S-mixture) and again treated with the esterase. Thus, by recycling the (R)-ester,
all the racemic ester is converted to (S)-naproxen



Elfspice incorrectly assumed that the NaOH was added to the solution to freebase the added amine hydrochloride. It is not. The freebase amine is to be used, and the purpose of the NaOH is to make the monosodium salt of the tartaric acid (which is a dicarboxylic acid).

In solution, the monosodium d-tartrate then preferentially forms a water-soluble salt with d-methamphetamine while the l-methamphetamine (still remaining in its freebase form) can be extracted with a non-polar solvent.

The reason all this happens is that because of the molecular shape of d-tartaric acid is such that in solution it fits better together with d-methamphetamine than with l-methamphetamine, given a choice (but will freely form a salt with both forms if enough acid is present, therefore one carboxylic acid group on each tartaric acid molecule is 'disabled' by the addition of one equivalent tof NaOH).

Instead in this case naproxen is used and should be solid I presume
azidesElfspice incorrectly assumed that the NaOH was added to the solution to freebase the added amine hydrochloride
 

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