Amphetamine Sulfate

Bumblebee · Wed May 18, 2005 8:50 am

I forgot:
is there a test for water that i can do with my solvents before using them?

What about putting a bit of the solvent in a test tube, and treat it with some water-reactive reagent like LAH, elemental Sodium or Potassium to it?
If it bubbles a bit there is some water in your solvent. And if you hear a "plopp" ( Shocked

), and after that "plopp" there is something dripping off your ceiling there was much water in your solvent, or it was just plain H20. Twisted Evil

Better don´t try this with Frankium or Caesium...

I guess somebee here knows a better way to test for water...

IndoleAmine · Dreamreader Deluxe

Its called Franzium, not Frankium. Wink

You could always dip some blue Cobalt Chloride (anhydrous) test strips into your solvent - they are deep blue in color, and when they turn pink H2O is present.

You can make them by soaking paper strips in saturated CoCl2 solution and drying them thoroughly in an eccsicator over silica gel (be careful when preparing the salt solution, too much H2O and it will become pink immediately, and then you'll have to dry the whole shebang thoroughly again. So use H2O just dropwise!!)

i_a

IndoleAmine · Dreamreader Deluxe

BTW water is indeed our enemy here, since the sulfate is very soluble in it.
But IMO theres no need for drying amine/IPA and H2SO4/IPA each with MgSO4; better dry your IPA with MgSO4, filter off and preferably redistill, then dissolve amine in it, dissolve H2SO4 in IPA too, then add acid soln. to amine soln. dropwise with good stirring until pH=7.

Use 0.5 mol H2SO4 per mol amine, not more!

When you have neutralized all basic substances, its time to get rid of the H2O traces. This is easily done by adding anhydrous Et2O or even better in this case, anhydrous acetone. Both solvents have the ability to "soak up" and bind water to some extent (ether less, acetone more). And further they dissolve all organic non-amine impurities very well and thus are an excellent method of "in-situ" cleaning for your sulfate salt.

Since your amine sulfate is virtually insoluble in cold IPA, concentrating the mother liquor to obtain a second crop is somewhat futile. The only loss can occur due to trace amounts of H2O or excess acid, both can be avoided if the right precautions are taken.

This technique works well for hydrochlorides since they are generally soluble in alcohols and require raising their concentration in order to make them crystallize completely - if too much solvent is used at least.. Wink

BTW gassing nonpolars with HCl to make crystals is not very good if the hydrochloride has a tendency for being hygroscopic (like with met.h), it makes only small amorphous solids at best - no crystals. And if the slightest impurities are present, everything will oil out and you'll have to remove all nonpolar and add acetone anyway to make it solidify, further you cannot exactly determine the amnt. of HCl used correctly when gassing..

Better use standardized pre-gassed HCl/solvent solutions, measure out the needed amount, and there you go - very easy and much cleaner, plus you avoid the need for setting up/running a HCl generator each time you need anhydr.HCl... Wink

icecool · Insistent Chemist

SWIMs notices when adding acetone to the mixture of crystals.
When a beaker is thick and full of amphetamine sulfate SWIM adds acetone and then it looks like a lot dissolves of course there is more solvent present but it just seems a lot dissolves in the acetone.
Insted of making the crystals purer etc.

IndoleAmine · Dreamreader Deluxe

ANHYDROUS, ice-cold acetone, not simply acetone from the paint thinner can... Rolling Eyes

(amph sulfate is insoluble in acetone, even more than in IPA or EtOH - thats a fact)

Try another drying agent, MgSO4 is not very good.

Did you try filtering off without acetone, and just rinsing with it? Also, did you chill the solution in the freezer before filtering? Or are you just estimating that you have "less" because things don't look as dense anymore when Me2CO is added maybe?

icecool · Insistent Chemist

I assume it, but I am quite sure that there actually was less.
And it was directly from the paint can.
And it was not icecold.
But SWIM did add it while the rest of the mixture was put in the freezer.
So the roomtemperature beaker with crystals to that was added acetone and that was put in the freezer.
Next time SWIM will dry it with moleculair sieves Wink

Ow and what about H2SO4 is that good when it is like 60% or so insted of GAA?
Or dilute HCl?

brain · Linguist Extraordinaire

i use lastety H2SO4 98% + IPA -its quite good ! dont hawe to add acid by drop with fear that product will disolwe Smile

icecool · Insistent Chemist

I mean insted of GAA for dissolving the P2NP in...

brain · Linguist Extraordinaire

i dont have GAA because its 6x time expensiwer than 80% ACOH !! ;]

-i always use 80% AcOH !! ...

-mix IPA+AcOH [i dont add water to it] - then i add to it Al , then Hg salt ! , after couple of minuts, I add fine powdered P2NP crystals ! not solution ! Smile

in small portions, not at once ! because reduction will stop ! after 4-5min, all P2NP is added.

-you was meanin reduction? i think Smile

... H2SO4 instead GAA ... hm - i cant help you, just dont know, I can check it after ~6-7 days, i will meke another reduction on bigger scale... in 20l "flask" 3-necked ! [not mine Sad

my friend's ] Smile

IndoleAmine · Dreamreader Deluxe

Mineral acids are mucho stronger than carboxylic acids (!), you would probably have to add it in dilute form and dropwise over several minutes to hours, or else everything might foam up violently, andn decide to spontaneously jump out of your 22L three-neck flask and to your lab ceiling... Shocked

Formic might too, but could also be good for lots of undesirable side rxns.

60% acetic works very well too (and is OTC).

(photography supplier, for making "stop baths" for neutralizing residues of "developer" on freshly developed photos, after taking out of developing bath - just refuse buying the better citric acid, and insist on the normally inferior acetic stopping bath because "you know already how its done properly with it"... Wink

)

BTW does anyone know if acetic can be concentrated by refluxing in dean-stark trap together with ethyl acetate? It should be stable in aequous acetic (no decomposition into EtOH and GAA), and it can remove H2O azeotropically (bp of azeotrope far below 80°C IIRC). So it should be possible to continuously remove all H2O from aequous acetic by refluxing with anough EtOAc for several days, right?

(I know it works with butylacetate, any reasons why it shouldn't work nicely too with the almost OTC ethylacetate?)

i_a

icecool · Insistent Chemist

Just wanted to mention when extracting the whole she-bang (like 600ml) with 2x20ml ether for example.
When you do that you will get something like 140ml of extract which does not dissolve in the rest.
This is IPA (if you used that for dissolving the P2NP in), which is combined with the ether.
When doing a wash with brine it will remain the same volume.
But when you let that stand for a while crystals may form (At least that happened to SWIM) so he added just plain water without NaCl dissolved in it to dissolve those crystals.
Suddenly there is almost no ether extract left Shocked

EEEK!!!
Okay after thinking some time, SWIM came to the conclusion that the IPA now mixed with the water and went out of the ether layer... Cool

Just for the people who don't know.
And don't add the NaOH solution too quickly happened to SWIM and quite some mess shot out of the condenser and all over the place in the fumehood so watch out!
Suddenly it started to react it takes a while so be patient before adding more.
Just like with HgCl2 if you add more because nothing is happening just wait 10 minutes before actually doing so, it can prevent heavy reactions.
And a overhead stirrer REALLY improves this Al/Hg reduction! Very Happy

IndoleAmine · Dreamreader Deluxe

If I extract 600ml aequous solution with 40ml ether, I'm usually left with nothing - because ether dissolves in H2O at a rate of about 10ml/100ml, so you need 400ml H2O to fully dissolve 40ml Et2O.

BTW you can get rid of the IPA by washing with dolute NaOH solution, IPA is miscible with it, but amines are not.

And it is sometimes advantageous to use much, much solvent.. Wink

icecool · Insistent Chemist

It is indeed better to use more non-polar solvent to extract the honey.
But well ether is very expensive for me so that is why I use as little as possible.
The total volume was 600ml...
And it didn't dissolve in there, don't know why, but well it did mix with the IPA and the ether was poured in a strong NaOH solution with the Al and all inside.
So it wasn't just water but very strong alkaline.
I guess ether is even less soluable in alkaline solution then in just water.
Anyway SWIM got his product so he's happy.
Besides of a part gone lost by spitting out of the condenser.

icecool · Insistent Chemist

It happened twice to SWIM now that when adding the H2SO4 to the freebase that after getting nice white crystals and filtering.
That everything in the filter in volume decreased a lot (obvious since it contains a lot of fluid).
But then it turns dark purple! Shocked

This time SWIM used anhydrous acetone to dissolve the freebase in and also used acetone to dissolve the H2SO4 in...

IndoleAmine · Dreamreader Deluxe

purple = too much H2SO4.

Try filtering off the mass of white solids BEFORE adding more acid soln. to the filtrate, then you have nice white sulfate (don't forget to wash in buchner by deattaching vacuum, adding acetone, stirring up the filter cake carefully as to not move the filter paper, and then re-attaching the vacuum and sucking dry, also repeating this 2-3 times is necessary to remove all organic impurities.)

i-a