Methamphetamine synthesis from P2P via Aluminum amalgam

[Fenster]

Can I make Methylamine in situ. via nitromethane like they do when reducing MDP2P

 

[joejoe]

Would like to ask,do I still need become hydrochloric acid?Or is this already the final product?

 

[Hank Schrader]

P2P + Nitromethane. You can do that.
This only works with Al/Hg
Will not work with sodium borohydride.

 

[UWe9o12jkied91d]

can i replace the methylating agent with formaldehyde?

 

[HerrHaber]

formaldehyde and primary amine gives the corresponding imine, which even though can be reduced by NaBH4, STAB (Na(OAc)3 aka sodium triacetoxy borohydride is much preffered since it has a strong prefference for reducing imines, also NaBH3CN id used for this purpose but somewhat toxic and expensive

 

[UWe9o12jkied91d]

Yes but I think this dosen't answer my question.

 

[HerrHaber]

there is another way of using dimethylsulfate (aka Me2SO4) and concentrated KOH a.q. reagents must be dropped over the stirring sollution in solvent from two dropping funnels (the Me2SO4 absolutely needs to have an appropriete size pressure equalizing one since your breath must be held as long as the bottle is opened meaning transfer and all that); the KOH solution can be from a simpe dropping funnel and it should start dripping first (3 drops) then the methylating agent at the same rate (drip rates are 1drops/minute (as close as possible) when done I will not bore you with workup but it's simple.

 

[G.Patton]

Hi, It won't formaldehyde won't react with P2P by reason that it is electrophile as P2P. You can try Leuckart amination with N-methylformamide or Formamide. They are nucleophiles and will reacts with P2P.

 

[Andrzej]

(step 6.) What should be the range of temperature of vacuum destilation (to effectively get rid of impurities, and avoid freebase decomposition)?

 

[HerrHaber]

Right question to ask but the answer is in the relationship between the strength of vacuum and temperature (the more negative the pressure the lower the boiling point) I suggest not playing arround with super strong vacuum if you have no experience before hand. God luck and good speed!

 

[Andrzej]

Thank you for your answer. Is there any critical, upper temperature limit? (or maybe proper question will be - what is decomposition temperature of methamphetamine freebase?)

 

[HerrHaber]

Yet again you ask the most reasonable and necessary question (now I don't know precise data by heart and won't give you unprecise information but I am educative in attitude towards you and help you learn how to learn for yourself). There is a diagram that is followed by every chemist with respect to the relationship between negative pressure (vacuum) and temperature, you have to seek this for yourself (I promise you will not have much trouble finding it). The point is to check the data and have the vacuum at least slightly below the normal (ambient) b.p. of your compound to be distilled (foaming spoiler alert). I also reccomend Vogel's practical organic chemistry book that you can download as .pdf without much seeking (it also has the above mentioned diagram and it explains pretty much everything you need to know with regard to preparative chemistry). You will become a much better profesiional chemist after reading the handfull of relevant material from this reference. I just gave you the best tip I give to anyone. Remember that the knowledge you work for, it forever will be yours.

 

[Andrzej]

I probably found... I post for others:

freebase methamphetamine boiling point: 93°C at 15 mmHg

source: https://chemistry.mdma.ch/hiveboard/rhodium/meth.hi-p.html
("the oil was vacuum distilled at a vacuum of 15 mmHg at 93 degC.[NOTE 5]")

 

[Andrzej]

(step 1.). I understand it that to just put those ingridients together in flask and start cooking... And my questions are:

1) Doesn't the temperature will grow up dramatically, spontanously after adding HgCl2(or HgNO3), and need to control it to avoid boiling over?

2) Shouldn't I prepare an aluminium amalgam before adding the rest of ingridients (P2P, EtOH, Methylamine)? Or it doesn't matter and I can just put in the flask all ingridients together and start reflux?

3) Is there any difference what alcohol will I use as a reaction solvent (for example methanol or isopropanol instead of ethanol)?

 

[UWe9o12jkied91d]

1)It’s not too bad, given it starts of as one-pot it ramps up slower and from my observations dosen’t go as crazy as traditional amalgam with p2np for example.apply cooling only if absolutely necessary.
2) you should follow procedure.
3)Both ethanole and isopropanole worked for me, at least I think so, I obtained the same product with both.

 

[mithyl2]

there's a video of this synthesis that may show the details for second question.

 

[HerrHaber]

The whole point is that i-PrOH as opposed to EtOH is much less miscible with strong alkaline a.q. solutions and much more easy for salting out (saturating the water layer with salt or whatever increases your ionic strength will cause it to separate and float on top, be warned that too vigurous shaking of i-PrOH with concentrated a.q. base solution tends to form emulsions that will require your waiting time, and if you are using DCM or similar you may have to wait even days for the layers to separte in case you shake too strong but the organic layer will be on the bottom and NaCl may not be your best friend).

 

[Doubleboil]

7. Methamphetamine free base is dissolved in x3 volume of dry acetone.


Can acetone replaced with ethanol or methanol or dcm?

 

[UWe9o12jkied91d]

Ethanol and methanol have too high affinity for water, dcm might work, I also heard people use tolueen

 

[HerrHaber]

acetone is strongly advised for precipitation purposes

 

[mygodson]

1-phenylacetone is not easily available and can be reacted with 1-phenylisopropanol and methylsulfonyl chloride to get methanesulfonate, and then methylsulfonyl and methylamine reaction solution can get the target product.