Isomers and tartaric acid

[Davidrobinson]

I have never split isomers. Can anyone who has done this process clear this up for me.
There is L+ tartaric acid {which is the dexto isomer, what is easy to buy )
And D-tartaric acid(which is Levo, what is hard to buy besides from china)
I am a little bit confused reading threads and articles about actually doing it. So say i use L+ tartaric acid which is dextro isomer, and i have 1 mole of freebase meth/ampt. Am i using this to crystallize the full mole of freebase to then produce
D meth/ampht D tartate and L meth/ampht D tartate, which in turn will give these two isomer different solubilities?
Or will the L+ tartar acid selectivity crystallize the D isomer of my freebase, which then this will mean i need 0.5mole of L+tartaric acid for 1Mole of freebase.
I have read alot of conflicting infomation, its very confusing when it comes to tartaric acid. If anyone has experience, it will be well appreciated.

 

[UWe9o12jkied91d]

here, i made this a while back, the first row describes "my" procedure, i didnt go into detail for D-tartaric acid route because I don't have first hand experience, but using L-tartric in excess as described produces, I think atleast, pretty optically pure product, I don't have a way to prove it yet but the theory checks out, as well as the pharmacology being noticeably better, lower heart rate, no spasm, reduced bruxism.Also the fact that L-tartaric acid(they make the distinction) gets siezed on the regular if you keep up with the literature.It's a case of "trust me bro" but like I said, the theory is solid.

I will put in some work these coming days, working "on the record" with my results and proportions and I might open a thread to show my findings, or post here idk

also excuse the artwork, I am not the best graphic designer

 

[G.Patton]

Good job, thank you.

 

[G.Patton]

There is illustrated version in the end of topic. I don't know why people don't look and read there (Pic. 17-20)

Dextroamphetamine synthesis (Nabenhower, 1942)

Introduction At the moment, there are many ways to synthesize dextroamphetamine. They can be divided into 3 types: biosynthesis (using biomass), direct synthesis, and synthesis of racemic (the sum of l- and d-isomers) amphetamine followed by separation of optical isomers. In our case, a...

bbgate.com

 

[Ihml]

Could a normal paper fillter be used for filltration, or would a borosilicate glass filter need to be used instead? Since amphetamine is a weak base with pH about 11.

 

[UWe9o12jkied91d]

Also need to mention tartrate product is not so sensitive to low pH, so an excess dosent really hurt, the solution gets red, indicating the waste portion is spolied and the excess acid floats to the bottom much quicker than your flocculant but your solid holds up wholly, and comes out nice and white when filtered, won't go POOF like other offenders *ahem*

 

[Davidrobinson]

EDIT: D meth/ampht L tartate
L meth/ampht L tartate

 

[UWe9o12jkied91d]

come again?

 

[Davidrobinson]

Sorry i couldnt edit my post

 

[Davidrobinson]

thank you, so the L+ tartaric acid selectivity crystallizes the D freebase, thats right isnt it?
could you not put your product under a polarimeter to check the rotation, this will confirm your product is oppitcally pure. I think your need a average rotation of +12.5 for D isomer of meth, i will have to double check this tho.
it would be good if you posted your results here.
what do you think the vest solvents ect is best to use?

 

[UWe9o12jkied91d]

ideally an alcohol + freebase, but integrated in the overall process it makes more sense to not steam distill as use extracts as is, as they will undergo at least 1 acid base purification by the end of it just by the nature of the process, sometimes 2.
as far as a polimeter I dont have access to one, I could prepare a racemic salt solution to compare its refraction indices but I'm not sure that's terribly conclusive

 

[Davidrobinson]

We should really steam distilling the racemic freebase beforehand. It will probably make this alot eaiser. What about a bi phase system consisting of the tartaric acid in water and freebase in the non polar , and mix them together. Then the D isomer tartate should migrate into the water layer and the L freebase stay where it is.
I will try both and let you know

I will test it on my polarimeter when i have tried these methods

 

[UWe9o12jkied91d]

distilling is a pain in the ass for me, but you go right ahead, the system you are proposing dosen't sound too bad, the only thing I could protest in regards to would be tartaric acid's solubility in water, but I'm not sure how or if it could affect the process, I am courious to your findings, keep us posted

 

[Davidrobinson]

I will , update this thread in a few days. Thanks

 

[UWe9o12jkied91d]

an alcohol and not acetone with the reasoning that tartaric acid is more soluble in alcoholes rather than acetone, it might work better in acetone I haven;t tried

 

[Davidrobinson]

Them diagrams are a great help , nice one. When i try it i will post my results here

 

[btcboss2022]

I think something wrong with graph.
If you use L+-tartaric acid(cheaper and easier to find)the D enantiomer(amph,Meth) will be in the solution not in the solid as there appears.
If you use D-tartaric acid(more expensive and difficult to find) the D enantiomer(amph,Meth) will be in the solid.
Thanks.

 

[G.Patton]

His scheme is correct. Salt is precipitated into the solid state. No difference, d-amphetamine l-tartaric acid salt or l-amphetamine d-tartaric salt. You can change acid and get difference isomer in the solid state with following procedures.

P.S. same for methamphetamine.

 

[UWe9o12jkied91d]

Ok, but even if it were like you said, which I don;t think it is, it would still be convenient, as long as ONE of them precipitates you have the ability to separate no matter which way

 

[btcboss2022]

"No difference, d-amphetamine l-tartaric acid salt or l-amphetamine d-tartaric salt"
I know that what I mean is that with L+tartaric(d-tartaric/dextrotartaric/D isomer) you will have have the D-amph or D-meth in the solution part not in the solid part.
Thanks.

 

[Joker_55555]

Hello, does methamphetamine synthesized from the method of ephedrine and pseudoephedrine give the d-methamphetamine isomer with 99% purity? If not, how much?

 

[Ihml]

I’m not Patton, but: it’d produce only D-meth of the ephedrine that was used was derived from a plant, since plants naturally only produce L-ephedrine (which turns into the opposite enantiomer after reaction - D-meth in this case). If chemically synthesized ephedrine was used, than you’d get racemic meth, because ephedrine synthesis isn’t stereospecific.

 

[Davidrobinson]

Yes g.patton, eirther way the both isomers are separated, one in the solvent and one as salt