1-Phenyl-2-propanone (P2P) Leuckart amination to amphetamine and methamphetamine. Smale scale.

[Selassi]

Swim got a question regarding a different variation on this method:

After the first step (boiling with formic and formamid), they now boil again the organic phase with water and NaOH instead of the reflux with HCl.

Can someone explain to me the metrics on this different second step to me? Swim has never done it this way but it seems to save a lot of time in contrast to the oldschool method with refluxing HCl.

What strength of caustic/water and how much is introduced to the reactor per L of product?
How long should swim boil this reactionmixture at what temp?

 

[waltjr5858]

You can do hydrolysis with a base or an acid...

 

[Curiousonion]

Why such a low yield for this, does anyone have a higher yield method for methamphetamine?

 

[Chemdog010297]

Red p, maybe aluminum

 

[Saul]

that is not right wrong info that thesis guy make big mistakes

ammonium carbonate is never used directly with p2p.
First, ammonium formate is made.
The ammonium format is easily made via ammonium carbonate and formic acid. Titrate
to a nice pH of 7 and remove the water.
Only then can it be used with p2p

 

[waltjr5858]

Yes ammonium carbonate can completely be used in this reaction directly it's actually a very popular method in many countries and makes ammonium formate in situ.... if you're not 100% sure what you're saying on here don't

 

[G.Patton]

Do you use reflux condenser and fume hood?

 

[waltjr5858]

In a write up that most people are reading to do this leuckart with formamide and p2p specifically... what is the purpose of a 15 min reflux with 30% h2O2 with the reaction mixture after you have already done the first reflux with formamide and p2p. Does it clean up or oxidize something? I mean this is prior to the hydrolysis. I just can't think of what it would do. I mean most people do it without it but it was obviously added for a reason in a actual professional write-up.

 

[G.Patton]

Sorry, but I don't clearly understand about what "15 mix reflux" are you talking about? Can you be more precise. Refer to a step number.

 

[waltjr5858]

It's not on these instructions. When making amphetamine after the first 24 hour reflux on a different set of instructions they would reflux for 15 minutes with 30% hydrogen peroxide and then go on with hydrolysis. What was the point of the peroxide?

 

[G.Patton]

I have no Idea about what "different set of instructions" are you talking and hence can't answer your question.

 

[waltjr5858]

Ok... but in general then what would happen to the resulting solution if spun up with 30% peroxide?

 

[William Dampier]

The use of an additional amount of water in Leuckart reaction can increase yield. Who did it, can write about it here.

 

[TheNut22]

Yeah. In Leuckart, you have to make sure there is no water at all.

 

[southcost]

But we have a 12% water at least in our formic acid, isn't it?

 

[TheNut22]

I made my stonger hydrogen peroxides from 12% H2O2. I just carefully evaporated water from it.
I asked calculations from AI-robot assistant in chemistry. It is good at calculations, but don't expect to get right answers
from halogenations or the like ...

 

[loadingST]

I still havent tried the reaction but with good hydrolisis with KOH and then with HCL it shoud give high yield, and im afraid working with h2o2 to dont form any explosive peroxides and upon destilation to dont explode

 

[William Dampier]

Yes, it is better to exclude peroxide.

 

[YenaneY]

This questions are mainly regarding the actual chemistry behind the synthesis...
Why does one for the formation of the amine from the intermediate need H2O2 and HCl in the synthesis of amphetamine but only HCl in the synthesis of methamphetamine?

 

[William Dampier]

In fact, there is no need to use peroxide.

 

[waltjr5858]

But what was the purpose of the peroxide in the first place I believe he's asking

 

[waltjr5858]

I saw the same thing and nobody has an answer for it but it was done by actual professional chemist.... not clandestine hackers so id say its there for a reason but it will work without it. Probably to kill off so.e kind of side product or something.

 

[YenaneY]

I think it really is because the hydrogen peroxide helps promote the reaction, but the reaction of deformylation is generally easier on tertiary amines compared with secondary ones, which is why it happens more readily if N-methylformamide is used for methamphetamine.

 

[Pinkbay]

sir, In step 3, is heating required?

 

[rampage]

can you replace n-methylformamide with dimethylformamide?

 

[waltjr5858]

I don't think so