Methamphetamine Isomers Separation by Tartaric Acid

[Osmosis Vanderwaal]

@G.Patton I have some issues with this process that I hope you can explain to me.
There is no mention of D-meth-D-tartate or l-meth-l-tartate. These are the optically active stereoisomers and I've seen no evidence or mechanism that suggests these do not form. Being the optically active stereoisomers, the would crystallize at a higher temperature ( ie sooner) than the inactive ones. The order would go: D,D; L,L; D,L; L,D.
Why would it NOT be more cost effective and efficacious to use JUST l-tartaric acid, the natural occurring isomers, and remove the ,l l-meth crystals from the rm before concentrating and crystallization?

 

[G.Patton]

This is due to spatial obstacles. They cannot be formed. This is described in literature with other amines examples. Search for it if you're interested in.

You can, it's up to you. Result will be the same.

 

[EveryoneHatesCris]

Okay?

 

[Osmosis Vanderwaal]

@G.Patton I find it interesting that you are reacting ammonium chloride with sulfuric acid to make your HCL gas in this write up. I've never before heard of using that method but it is viable. Is there a reason that is preffered over the more common mixtures?

 

[G.Patton]

No difference, It's up you your local reagent availability.

 

[Osmosis Vanderwaal]

I like that there is no water to gunk up the works, like there is dehydrating HCL with H2So4. I think I'll adot this method andski the drying tube

 

[G.Patton]

It's easy to get rid of water by means of CaCl2 tube filter.

 

[Osmosis Vanderwaal]

sure, or a cold trap with H2So4 inline with the output, but if I skip that I can just have a flask, a claison adaptor with a pressure equalizing drop funnel and a hose adaptor on the side arm. 4 pieces of glass, only the drop funnel being extra from a basic distillation set

 

[prvnc]

The tartaric acid method works by selectively crystallizing d-methamphetamine as the l-tartrate salt. Control pH carefully during freebase conversion and HCl gas saturation. Hot filtration and recrystallization in ethanol boost purity but reduce yield (~30% loss normal). Always verify purity with Simon’s test. Exact tartaric acid ratios and repeat crystallizations improve results.

 

[Osmosis Vanderwaal]

theres a rule that says "a good chmist is an accurate chemist" Tartaric acid doesn't "selectively crystallise" anything. that misleading Also d-meth-l tartrate mixes more than one convention of chirality, considering
d-meth=L-Meth=R=meth=legal, and
l-meth=D-meth=S-meth=illegal