PNP's into amphetamines reduction on alu foil

IndoleAmine · Dreamreader Deluxe

I don't know about your MeOH - maybe just distill over a vigreux column and make sure you catch only pure MeOH/H2O azeotrope, then dry it with MgSO4...

Steam distillation has the advantage that you actually distill your amine freebase, without vacuum and still at very low temperatures. You have much cleaner freebase, and although you still have to evaporate the solvent, you have a waaay cleaner solution to basify and extract (->cleaner extraction, you get all out with less solvent!)

The proper way to steam distill this rxn is distilling off the alcohol first, then basify with lots of NaOH (it can get as hot as 100°C and begin to boil, but if you attach the dist.setup quickly, nothing is lost here!), then distill off the water/amine azeotrope at 98-99°C, and continue collecting distillate until the vapor temp. reaches 100°C (or bp of H2O where you live). Then proceed with basifying the distillate to free all amine (no need to be careful; since no Al is present in the distillate, no exothermic rxn occurs - just add some NaOH soln., gently in small squirts with stirring until pH is >13), and extract with any nonpolar you like for 2-3 times, combine extracts, wash 3x with satd. NaCl solution, then with H2O, then dry it (not with MgSO4; it reacts with amines! Better use anhydrous Na2SO4, silica gel or molecular sieves...), evaporate solvent, and measure out what you are left with.

for p2np: your amine has a density of 0.913g/ml at 25°C, and a mw of 135.21 - so 5ml would be 33.76mmol at 25°C, divide the calculated molar amount by 2 (= 16.88 mmol), and multiply with the molar weight of sulfuric acid (98.08 g/mol), you will arrive at 1.6557 grams H2SO4 for 5ml of your amine.

(weight of amine / mw of amine)*98.08 / 2 = weight of H2SO4 needed to make diamine sulfate

Now you just have to calculate how much more you need with the concentration of sulfuric you have (I will assume 98%), and divide through its density (1.84g/ml).

(1.6557g * (1 / 0.98 )) / 1.84 = 0.9089 ml H2SO4 are needed for 5ml amine...

Now dissolve 0.9ml H2SO4 in 20ml IPA, and add 80% (not more!!) of this solution slowly to 5ml of your amine dissolved in 20ml IPA, dropwise and with good stirring. When done, add 50ml anhydrous acetone, stir well and place in freezer for 1 hour, then vacuum filter the sulfate quickly and rinse with cold, anhydrous acetone, followed by cold, anhydrous diethyl ether, let air suck trough the filter cake for 10 minutes, then spread out to dry completely.

And NOW! (not earlier!!!) you can try and add more of your sulfuric solution (which you kept in a stoppered vial all the time of course) to the filtrate, in hope to get more sulfate salt out of it.

Good luck.

icecool · Insistent Chemist

SWIM is currently distill of the ether and will dissovle the amine in |MeOH anhydrous.
Then dissolve H2SO4 in MeOH and add that to each other.
Can also ether be used insted of acetone and what is it use?
And then place it in the freezer.
Extracts where clear to very little yellow.

IndoleAmine · Dreamreader Deluxe

The purpose of the acetone is to crash out the small amnt. of sulfate that will dissolve in the tiny amnt. of water present. It dehydrates the crystal structure, helping to form solids faster, and it also dissolves impurities and makes cleaner product.

Ether can be used too, but is expensive and not as good as acetone. Go buy some at the paint section... Wink

Be careful, you would not want to discover that your MeOH is impure by failing a crystallization with it... (don't you have any IPA or EtOH lying around?)

icecool · Insistent Chemist

You know SWIM doesn't know how to figure out what solvents SWIM can use SWIM does know quite something about solvents but just doesn't know what to use when.
If you tell SWIM it needs to be a aprotic polair solvent etc then SWIM can figure out what solvents can be used.
And SWIM is going to use ether to crash the crystals.
And SWIM got 5,33g of amphetamine freebase sudenly there was a very light white smoke inside the RBF when distilling so SWIM stopped since he didn't feel good with that.
Anyway he tested 1/3 of the freebase and got crystals and is going to vacuum filtrate it in 30minutes.
Anyway next time SWIM will also not use MeOH for the Al/Hg reaction.
And will use EtOH for the crystalization.
SWIM is going to form more crystals next with the rest of the freebase.
It is 3,21g freebase which will be dissolved in 6ml MeOH then to that will be added 0,6g H2SO4 which is dissolved in 5ml MeOH.
Then after filtration there will be added more H2SO4+MeOH mixture and that is 0,3g H2SO4 in 5ml MeOH and then filtrate again.
But succes but still learned a lot for next time.

IndoleAmine · Dreamreader Deluxe

icecool · Insistent Chemist

SWIM didn't steam distill it and the ether fucked up the crystals there are less crystals IIRC.
Before there was very little trouble stiring it because it was to thick now SWIM can stir it more easily.
So fuck the ether it just isn't dry enough.
Next time SWIM'll do that now it is better than before next time it'll be better then this time.
And SWIM added 0,3g H2SO4 in 5ml MeOH to 1,76ml freebase and that made crystals everything added....
So for 2 times as much also 2 times as much H2SO4 should be used 3,32 and 0,6g....
What is the point of drying over MgSO4 when you are going to add H2O to the distillation flask Shocked

IndoleAmine · Dreamreader Deluxe

Thats the reason why acetone is better - it doesn't need to be 100% anhydrous to work, can be dried more easily, etc.... Very Happy

You said you wanted to add 0.6ml to 3.21g, filter off, then add another 0.3ml - and those last 0.3ml are too much. Better add 80% of your 0.6ml solution, filter, then add the remainder....

The point is that you need water for steam distillation, but want to avoid exactly the same thing when removing solvent (with steam dist. you want to distill the amine; when removing the solvent, you don't want that of course).

Therefore you first add lots of H2O, steam out the amine, extract with solvent and then dry the solvent and remove it through dist., without having any water that can steam out any amine anymore...

You just need to dry your combined ethereal amine extracts after washing them with NaCl solution, and for this case its better to use no MgSO4 but other drying agents (its not recommended for drying amines).

And just for clarification of the whole process:
You are supposed to heat the post-rxn mixture in a distillation apparatus until all alcohol has been distilled away, then let cool down a bit and carefully add lots of NaOH solution, then apply heat again and steam distill out the amine together with H2O (add more H2O to the flask you are heating from time to time to comepnsate for losses), then basify the clean, water-like distillate you collected, and extract with a nonpolar (like ether) 2-3 times, then wash the nonpolar extractions with brine, then dry them over drying agent, then remove the nonpolar solvent by distillation and you are left with pure amine freebase.

Result: amine freebase distilled and ultra-pure, no solvent wasted, no mercury contamination, easy process. Happy chemist.

icecool · Insistent Chemist

Ah okay now I get it sorry for not understanding certain things so quickly and with solvents but if you tell me a bit more specifik the chemistry behind it I can learn it quicker then just telling me what to do.
Now finally after SWIM is being an insistent chemist Laughing

yields have gone up since now only 1/3 of total freebase made more amphetamine sulfate then before was made out of the same total amount of freebase which was red etc.
This one is light yellow after evaporating off the solvent though.
And SWIM noticed something, when adding the H2SO4+MeOH no crystals form so SWIM was like WTF! Evil or Very Mad

and after stirring like hell it suddenly got milk color and then whiter and whiter until full of crystals.
Really a proces which can be performed much better in bigger quantities like 50g P2NP reduced or so or 20 but it just sucks with 5g P2NP, respect for tetraeder doing experiments with 1,13g of nitropropene/styrenes!
Also for the other people which do such reations in that small scale.
Is it true that the H2SO4 and MeOH need to react for 30min before adding to the amine???

icecool · Insistent Chemist

SWIM was able to add 0,6g H2SO4 to the 2,77g of freebase all at once.
SWIM sayd 2,31 but that was calculated that not everything would be freebase so after filtration more H2SO4 can be added to see how much freebase it was actually.
Anyway next time SWIM will pour the little bit of almost pure freebase in a 50ml RBF since it started to do weird and shit because it was a too big RBF.
You can't distill 6ml in a 250ml RBF than a 50ml RBF is better.
Anyway also notes for next time will be written in SWIM's labjournal Laughing

brain · Linguist Extraordinaire

i was doing it on small scale, 1g p2np and less !! the yelds was similar, but the reagenst difficult to hande, but reaction easy to controll

icecool · Insistent Chemist

Okay respect for you too then Laughing

One question about steam distilling left, especially for indole amine.
Sometimes you say to after distilling the water+amine you add HCl and sometimes you say add NaOH.
What is the difference and what is right and what is wrong?
E.g All the Al crap with Hg etc distill it while basified then the distilate will be alcohol.
Then add more NaOH with lot of water then distill the amine+water then basify and extract and remove solvent and before wash with NaCl couple of times etc.
Sometimes you say the same but in the place where I made the words bold there it will be like this.

make it acidic with HCl and extract with non-polair solvent

And when you add HCl if I'm right the oil will float on top of water or is that when basified?
Anyway when you have it floating on top can't you just suck it off the water or put it in a seperatory funnel and then already have the pure freebase, insted of extracting and blabla after that.

IndoleAmine · Dreamreader Deluxe

confused?

I have just combined a standard acid/base extraction and a steam distillation procedure...

When you acidify something, all amine is dissolved in the aequous layer as the salt. This is the case when the rxn is finished (GAA in there!) as well as when you acidify the collected distillate after steam distillation.

In both cases, you are able to remove unwanted substances sharing similar solubility properties, like your amine freebase.

When you distill the post-rxn mixture (before basifying it!), you remove the alcohol while the amine stays in the distillation flask as its salt.

Then you basify to destroy remaining Al and neutralize the salt of your amine, so it will float to the top and can be steam distilled.

Then you steam distill out all substances that can be steam distilled, not only amine freebase but also some impurities/side products (I don't know about their identity; but you can be damn sure there are some!).

Then you have two options, the faster/dirty way and the slow/clean way:

a) add base to your collected distillate to make your amine float to the top (together with those impurities), then extract with ether or similar several times, wash with brine, dry and evaporate the solvent (recover!) to be left with impure amine freebase.

b) add acid to your collected distillate to make the water-soluble amine salt, then wash this aequous amine salt solution with nonpolar several times (DCM is very good here) to remove the impurities which didn't form any soluble salt and eventually are still floating on top as a greasy, discolored layer, and you are left with very clean amine salt solution, which you can basify to pH 13, extract with a "top-puller" like ether or toluene etc. several times, combine extracts, wash with brine, dry and evaporate solvent to be left with very pure amine freebase.

It depends on you which way you choose - either basify and extract directly, or acidify, extract, then basify, extract...

time or purity..

IndoleAmine · Dreamreader Deluxe

And please stop talking about "making amphetamine sulfate", thats not what we want to discuss here - right? Wink

brain · Linguist Extraordinaire

i done today litle amph*HCl ..... ?

just added HCl aq, to Ph=6,8 than add in exicator with P2O5, and claen white crystals were obtained-so simple... ? Smile

icecool · Insistent Chemist

Okay then I get it now.
One question remaining Very Happy

You sayd that the amine will be floating on top of the water why don't you just put the whole mixture in the seperatory funnel, since it is floating on top you can drain away the water layer and be left with freebase, no?