Dextroamphetamine synthesis (Nabenhower, 1942)

[yin-yang]

G.Patton​

Sulfate isn't perfectly white. You got rid of all water soluble impurities, now that's left to do few washings with acetone/IPA and should be left with ~95% pure salt?

I guess in that case there is no need to steam distill, no?

I ask because my gear is textbook looking but is active at high dosages and the high feels somewhat dirty.

 

[G.Patton]

Sulfate isn't perfectly white.

wannabeechemistIt is. I got absolutely white powder and saw different ones with good quality. Sometimes it has a little tint.

now that's left to do few washings with acetone/IPA and should be left with ~95% pure salt?

Yes, should be. Some amphetamine-relaed by-products still will be there. Steam distillation is a good option to get rid of by-products with different boiling point (for amph free base).

 

[johski]

3 quick questions, not all on topic here... wash meth with dichloromethane first? good or bad idea? what is the best way to make the freebase? Can the above procedures for amphetamine apply/take over methamphetamine as well?

 

[G.Patton]

3 quick questions, not all on topic here... wash meth with dichloromethane first? good or bad idea? what is the best way to make the freebase? Can the above procedures for amphetamine apply/take over methamphetamine as well?

johskiYou can open Meth topics and read/ask there.

Can the above procedures for amphetamine apply/take over methamphetamine as well?

http://bbzzzsvqcrqtki6umym6itiixfhni37ybtt7mkbjyxn2pgllzxf2qgyd.onion/threads/synthesis-of-methamphetamine-from-p2p-via-aluminum-amalgam.184/

http://bbzzzsvqcrqtki6umym6itiixfhni37ybtt7mkbjyxn2pgllzxf2qgyd.onion/threads/methamphetamine-from-p2p-by-nabh4-reduction-medium-scale.600/

 

[MadHatter]

I'll put this here also:
What really messed with my head in this description was the nomenclature concerning the tartaric acid. The text in the description uses the old nomenclature for the tartaric acid isomers, with lowercase "d" for dextro-tartaric acid. In modern texts and when you buy tartaric acid a capital "L" will be used for the same isomer: L-tartaric acid. So "d-tartaric acid" is the same thing as "L-tartaric acid".

To confuse things further, the other isomer, Levo-tartaric acid, is named "l-tartaric acid" in older texts, but "D-tartaric acid" in modern texts and in chemical companies.

Now, D-tartaric acid (formerly l-tartaric acid) is really expensive and difficult to buy. Often times it requires an End User Declaration to purchase in larger quantities.
L-tartaric acid (formerly d-tartaric acid) is however both cheap and accessible. It's a natural acid derived from fruits and available to buy from winemaking stores online. This is the one you want.
it's also very usable to resolve (it's called resolving when you separate enantiomers) methamphetamine, which is even more crucial since the L-isomer of meth is useless.

There's a pretty good article about resolving amphetamine isomers here, called "The Dutch Solution": (WARNING clearnet) https://www.thevespiary.org/rhodium/Rhodium/chemistry/amphetamine.resolution.html

This is an excerpt from the text concerning the separation of meth isomers:

Resolution of racemic Methamphetamine​

85 parts of racemic methamphetamine are introduced into a solution of 100 parts of d-tartaric acid in 1000 parts of methyl alcohol. After protracted standing about 100 parts of the precipitated salt are aspirated off and extracted with hot ethyl alcohol. Since the d-tartrate of dextrorotary methamphetamine is readily soluble in both methyl and ethyl alcohol whereas the d-tartrate of levorotary methamphetamine is sparingly soluble both in methyl alcohol and hot ethyl alcohol an extremely simple separation of the d-tartrates of the optical antipodes of the base is effected.

Reference: British Patent 508,757

So basically you dissolve meth or amph freebase in near-boiling methanol with L-tartaric acid in. Once the solution cools, crystals of l-amph/l-meth bound to L-tartaric acid will begin to crash out. You just filter these out and discard or save them.
I would then basify the solution with NaOH and evaporate off much off the alcohol, and add water to get a good separation of the freebase layer, extract it in a sep funnel and then bubble HCl gas through it if it's d-meth freebase or add sulphuric acid if it's d-amph freebase to get nice d-crystals.

 

[G.Patton]

So "d-tartaric acid" is the same thing as "L-tartaric acid".

DocXHi, you are wrong. They are different isomers. Please, read about isomers of Tartaric acid here.

 

[MadHatter]

Hi, you are wrong. They are different isomers. Please, read about isomers of Tartaric acid here.

View attachment 6601​

G.PattonFrom the wikipedia article you just linked to:

___________________________
Naturally occurring form of the acid is dextro tartaric acid or L-(+)-tartaric acid (obsolete name d-tartaric acid). Because it is available naturally, it is cheaper than its enantiomer and the meso isomer. The dextro and levo prefixes are archaic terms.[13] Modern textbooks refer to the natural form as (2R,3R)-tartaric acid (L-(+)-tartaric acid), and its enantiomer as (2S,3S)-tartaric acid (D-(-)-tartaric acid). The meso diastereomer is referred to as (2R,3S)-tartaric acid or (2S,3R)-tartaric acid.
___________________________

Which is the opposite of what you just posted? And exactly what I wrote? This image is from the same wikipedia article:

 

[MadHatter]

So L-(+)-tartaric acid is the same thing as d-tartaric acid and (2R,3R)-tartaric acid which is dextro tartaric acid.
D-(-)-tartaric acid is the same thing as l-tartaric acid and (2S,3S)-tartaric acid which is levo tartaric acid.

And DL-tartaric acid would be useless for resolution. Since it's a racemat itself and would crystallize both isomers of the amphetamine.

Goddamn chemical nomenclature is a bad trip in itself.

 

[G.Patton]

dextro tartaric acid or L-(+)-tartaric acid (obsolete name d-tartaric acid).

DocXI didn't read carefully. Actually it is not. I think there is mistake in Wiki because this statement contradicts to this picture. I've sent this pic which is clearly show that these are different isomers. I understand that it is hard to realize but...

 

[MadHatter]

Sorry for spamming, but I found the key. The image you post is from the wikipedia article on stereochemistry. It's faulty. That article is pretty heavily critizised in the Talk-section.

The picture I post is the correct one.

The prefixes l and d are just short for dextrorotary or levorotary: which way the molecule rotates polarized light. "l" = levo = to the left, "d" = dextro = to the right. But these prefixes are old and not used anymore.
In the modern nomenclature these have been replaced by the (+) for dextro and the (-) for levo.

The prefixes L and D (uppercase letters) refer to the Fischer projections of the molecules and have nothing to do with how they rotate light, but in what direction key parts of the molecule is drawn. They are in this case actually REVERSED in relation to the d and l prefixes: d is L and l is D.

So L-(+)-tartaric acid means: "a tartaric acid molecule that's drawn with the highest priority group at the top on the Fischer projection and the relevant group pointed to the Left, and rotates polarized light to the right", a.k.a dextrorotary, a.k.a dextro, a.k.a d-tartaric acid. This is the natural form of tartaric acid.

And, of course, vice versa for D-(-)-tartaric acid.

Now, as far as I understand, both isomers of tartaric acid can be used to resolve enantiomers of amphetamines. If you use D-(-)-tartaric acid you will get crystals of d-amph/D-tartrate crashing out, and if you use L-(+)-tartaric acid you will get crystals of l-amph/L-tartrate crashing out.
Using DL-tartaric acid would be absolutely useless, since it wouldn't separate anything: both enantiomers would crash out.

Phew.
I have spoken.

 

[BrownRiceSyrup]

Sorry for spamming, but I found the key. The image you post is from the wikipedia article on stereochemistry. It's faulty. That article is pretty heavily critizised in the Talk-section.

The picture I post is the correct one.

The prefixes l and d are just short for dextrorotary or levorotary: which way the molecule rotates polarized light. "l" = levo = to the left, "d" = dextro = to the right. But these prefixes are old and not used anymore.
In the modern nomenclature these have been replaced by the (+) for dextro and the (-) for levo.

The prefixes L and D (uppercase letters) refer to the Fischer projections of the molecules and have nothing to do with how they rotate light, but in what direction key parts of the molecule is drawn. They are in this case actually REVERSED in relation to the d and l prefixes: d is L and l is D.

So L-(+)-tartaric acid means: "a tartaric acid molecule that's drawn with the highest priority group at the top on the Fischer projection and the relevant group pointed to the Left, and rotates polarized light to the right", a.k.a dextrorotary, a.k.a dextro, a.k.a d-tartaric acid. This is the natural form of tartaric acid.

And, of course, vice versa for D-(-)-tartaric acid.

Now, as far as I understand, both isomers of tartaric acid can be used to resolve enantiomers of amphetamines. If you use D-(-)-tartaric acid you will get crystals of d-amph/D-tartrate crashing out, and if you use L-(+)-tartaric acid you will get crystals of l-amph/L-tartrate crashing out.
Using DL-tartaric acid would be absolutely useless, since it wouldn't separate anything: both enantiomers would crash out.

Phew.
I have spoken.

MadHatteryour clarification here across three comments here has been the most clarifying and absolutely useful thing ive fucken read in a while. thank you. I know you posted this like 8 months ago so im just saying it now in case no one else does, this is what i needed to clear the air about all this shit... for years i didnt get it and was too confused to try and come close to making sense of it.... thank you... seriously

 

[G.Patton]

Sorry for spamming, but I found the key. The image you post is from the wikipedia article on stereochemistry. It's faulty. That article is pretty heavily critizised in the Talk-section.

The picture I post is the correct one.

The prefixes l and d are just short for dextrorotary or levorotary: which way the molecule rotates polarized light. "l" = levo = to the left, "d" = dextro = to the right. But these prefixes are old and not used anymore.
In the modern nomenclature these have been replaced by the (+) for dextro and the (-) for levo.

The prefixes L and D (uppercase letters) refer to the Fischer projections of the molecules and have nothing to do with how they rotate light, but in what direction key parts of the molecule is drawn. They are in this case actually REVERSED in relation to the d and l prefixes: d is L and l is D.

So L-(+)-tartaric acid means: "a tartaric acid molecule that's drawn with the highest priority group at the top on the Fischer projection and rotates polarized light to the right", a.k.a dextrorotary, a.k.a dextro, a.k.a d-tartaric acid. This is the natural form of tartaric acid.

And, of course, vice versa for D-(-)-tartaric acid.

Now, as far as I understand, both isomers of tartaric acid can be used to resolve enantiomers of amphetamines. If you use D-(-)-tartaric acid you will get crystals of d-amph/D-tartrate crashing out, and if you use L-(+)-tartaric acid you will get crystals of l-amph/L-tartrate crashing out.
Using DL-tartaric acid would be absolutely useless, since it wouldn't separate anything: both enantiomers would crash out.

Phew. I have spoken.

DocXSorry, I was confused. L(+) isomer can be used to get (-)D-amph/methamph. Procedure a little bit different from mine and you can get another isomer. I worked with D-Isomer only. You'll get D-amph L-tartaric acid as an precipitate.

Extract with 5 ml of petroleum ether and warm the solution, add 2.45 g of d-tartaric acid in alcohol solution to the mixture. Then add alcohol until completely dissolved and cool with stirring. The l-amphetamine d-tartaric salt precipitates. The d-amphetamine remains in the solution. You can repeat procedure of cleaning precipitate of l-amphetamine d-tartaric salt by methanol to increase yield.

 

[Mr.Blanks00]

So L-(+)-tartaric acid is the same thing as d-tartaric acid and (2R,3R)-tartaric acid which is dextro tartaric acid.
D-(-)-tartaric acid is the same thing as l-tartaric acid and (2S,3S)-tartaric acid which is levo tartaric acid.

And DL-tartaric acid would be useless for resolution. Since it's a racemat itself and would crystallize both isomers of the amphetamine.

Goddamn chemical nomenclature is a bad trip in itself.

DocXhi, is this product the same as L- and can it be used?

 

[Saul]

hi, is this product the same as L- and can it be used?

Yusuf
search on the lable for the cas nr

D-Tartaric Acid CAS 147-71-7,
L-Tartaric Acid CAS 87-69-4,

(1) dextrorotatory tartaric acid (d-tartaric acid) found in grapes and several other fruits,

(2) levorotatory tartaric acid (l-tartaric acid) obtained chiefly by resolution of racemic tartaric acid,

 

[G.Patton]

hi, is this product the same as L- and can it be used?

Yusufread my previous message please

 

[MadHatter]

hi, is this product the same as L- and can it be used?

YusufYes. Absolutely. It's L-(+)-tartaric acid, or dextro tartaric acid.
This is the same as d-tartaric acid.

Procedure: as in the description of this thread (for amphetamine) or as in this article (clearnet).

 

[G.Patton]

Procedure: as in the description of this thread (for amphetamine) or as in this article (clearnet).

DocXWhy do you refer side resources while in this thread this procedure is described?

 

[MadHatter]

Why do you refer side resources while in this thread this procedure is described?

G.PattonI did refer to the description in the thread. Read the answer again.

The other reference is broader and also gives information about the recrystallization of meth and how to use other resolving agents than the pure L-(+)-tartaric acid. I think it adds value to the thread. Surely it's ok to give references when you post info on this forum? At least, it has been done many times before. If you have issue with that reference, please tell what it is.

 

[G.Patton]

other resolving agents than the pure L-(+)-tartaric acid.

DocXI didn't find any other option in this article. Also, recrystallization procedure is the same as for usual meth. By the way, you can use flash chromatography to separate isomers but this method to much complicated.

 

[MadHatter]

I didn't find any other option in this article. Also, recrystallization procedure is the same as for usual meth. By the way, you can use flash chromatography to separate isomers but this method to much complicated.

G.PattonHaha, sorry! I thought I pasted the link to a Rhodium article . I'll fix my error.

 

[MadHatter]

This is the article I meant to reference: https://www.thevespiary.org/rhodium/Rhodium/chemistry/amphetamine.resolution.html

In that reference, they used this and seem to have made an analysis of the optical isomers isolated:

Resolution of racemic Methamphetamine using O,O-Dibenzoyl-R,R-Tartaric Acid​

Using O,O-Dibenzoyl-2R,3R-Tartaric Acid (made by acylating L(+)-tartaric acid with benzoyl chloride) in dichloroethane/methanol/water, racemic methamphetamine can be resolved in 80-95% yield, with an optical purity of 85-98%.

Experimental

15.0g (100 mmol) of racemic methamphetamine freebase was dissolved in a mixture of 20ml dichloroethane and 15ml water. A solution of 9.4g (25 mmol) O,O-Dibenzoyl-2R,3R-tartaric acid in 40ml of dichloroethane and methanol (see amounts below) was added to the two-phase solution during 30 minutes at room temp. From the stirred solution the crystallization starts in 10-15 minutes. The resulting suspension was stirred at 5°C overnight, then filtered. The precipitate was washed on the filter three times with 5°C dichloroethane and air dried under a heat lamp. The precipitated salt were dissolved in 30ml 2N NaOH and extracted with 3x25ml dichloromethane. After drying over MgSO4, filtering and evaporation of the solvent, the methamphetamine freebase was obtained, which can be dissolved in diethyl ether and bubbled with dry HCl gas to obtain the crystalline hydrochloride salt.

Using 3ml methanol in the above procedure gave d(+)-methamphetamine in 93% yield and 85% optical purity, and 18.8ml methanol gave 78% yield in 98% optical purity.