Amphetamine Sulfate

DrugPhreak · Working Bee

SWIDP never had an amphetamine dream before and is wondering if it would be necessary to titrate with H2SO4 or could concentrated just be dripped into the non-polar slowly since this molecule holds up so well under acidic conditions etc?

brain · Linguist Extraordinaire

so, I extract the amine with ether, then add to this solution conc. H2SO4... but not to much ! because precipate - dissolw !! an after a while make a red solution, whih can be thorwe out...

hahas · Mon May 09, 2005 3:21 am

you might have a hard time getting the acid to dissolve in your non polar and it would sink to the bottom if it does. so any precipitate formed could fall into this.

a viable option to titration and crystallizing by crashing out from conc. solution with an alcohol - distill the solvent, dissolve the residue in drugstore 91% IPA, and neutralize with acid (not the really concentrated stuff), and add nonpolar or ether to this to get all of the salt out.

bio · Working Bee

The unmethylated amine was never crystallized by bio but a few things he's read comes to mind regarding the sulfate. Do a Hive archive search it should be easy to find.

IIRC the sulfuric acid will char the amine if too concentrated and non polar solvents are not recommended due to the solubility problem using dilute
acid. It's something like 15% H2SO4 added slowly to the amine in plenty of ethanol. Then crystallizing in the usual manner.

As you are unsure of purity use less than the calculated acid or you will likely end up w/ a mess. Then add more after weighing the first crop.

IndoleAmine · Dreamreader Deluxe

Dissolve amine in 4x its volume of IPA, add 80% of a solution of half-molar amount H2SO4 99% in 4x its volume IPA dropwise with stirring, then add acetone and chill for 1h. Filter off, add remainder of H2SO4 soln. dropwise to precipitate the remainder (be careful - too much H2SO4 and everything will redissolve again, forming the hydrosulfate salt which is too soluble and cannot be isolated)

DrugPhreak · Working Bee

Yeah, SWIDP was searching through the Hive archive, but didn't find much on this. SWIDP probably didn't use enough search terms though. This amphetamine will be produced via HI/RP of PPA. So, after the post reaction fluid is based and extracted into toluene the toluene will be distilled. Before this post was made they where going to dissolve concentrated H2SO4 in anhydrous EtOH (1:1) and then drip small amounts slowly into the toluene, which probably would have turned into a nightmare, but now with the information from the previous posts they are planning on proceeding like so with this 10gm nano...

1. Distill the toluene from freebased post reaction fluid.

2. The freebase amine residue is dissolved in 30ml of anhydrous IPA (SWIDP estimates they will be left with ~7ml of residue after toluene distillation).

3. 1.2ml of concentrated H2SO4 is added to 6ml of anhydrous IPA.

4. 80% of this alcoholic acid solution is added to the amine in small drops with stirring. 110ml of anhydrous acetone is added and it's placed in the freezer within an igloo (or another suitable container) to allow for slow precipitation. The precipitate is vacuum filtered, washed with cold anhydrous IPA/EtOH and Et2O, and allowed to air dry. This process is repeated with the mother liquor and remaining alcoholic acid solution.

Thanks for the help!

IndoleAmine · Dreamreader Deluxe

DrugPhreak · Working Bee

Oh yeah... duh! I forgot about the density… in my previous post I tried to scale down the equimolar ratio of acid 19 times for this nano, but it has been edited with the correct info. I never knew it was actually a diamine. Thanks!

IndoleAmine · Dreamreader Deluxe

Looks better, just make sure to add only 80 percent of your alcoholic sulfuric solution at first, then add acetone and cool (mmost will precipitate directly upon addition, but the last percent do only precipitate when it is chilled for a while).

Then filter off the precipitate, wash with IPA/EtOH followed by acetone (or Et2O) to facilitate fast drying, and if you have secured 80% of your crop this way, you can go ahead and try precipitating the remainder by careful dropwise addition of more of your H2SO4/IPA soln., until further drops don't cause any more precipitate formation. Then its finished. Add some more acetone, chill a while, filter off.

If you add a few drops too much, everything will dissolve immediately, and you loose it - so watch out, be careful!

Good luck.

btw

DrugPhreak · Working Bee

OK... SWIDP has edited it again and plans on following that procedure. SWIDP is just waiting for a few things and then it's dreaming time! Smile

icecool · Insistent Chemist

Anyone tips for purifying amphetamine sulfate?
Tips on how to recrystalize it or info on where to find info on how to do it?

IndoleAmine · Dreamreader Deluxe

You can purify while the amine is in freebase form, by dissolving it in dilute acid, washing couple times with DCM, then re-basifying and extracting the purified amine with ether or toluene.

The salt can of course be washed with several solvents too, in which it should be insoluble of course, to improve purity by washing away the organic contaminating substances.

Finally, the free base can be vacuum distilled (of course only if you are working with larger amounts) and the forerun and remainder saved separately (recycle - throw into next batch!), the middle fraction collected at the right bp will be >95% pure amine, and after three succeeding vac distillations, >99% purity can be had...

...but to my knowledge, the sulfate cannot be recrystallized effectively from solvents other than water, and even that isn't easy due to the high solubility of the sulfate in it.

Try and suspend some amine sulfate in anhydrous IPA, heat to slight reflux with a heating bath, and then add hot, distilled water dropwise with good stirring, until everything is dissolved. Now let cool VERY slowly without any stirring or disturbing the solution in any other way (cover with aluminium foil, and don't even look at it! Smile

), preferably over several hours (use a big oil bath, it cools very slowly).

When it has reached room temp., place in fridge until cool, then into freezer until ice-cold.

Somewhere in between, crystals should appear.

Take care to not stir the solution by any means, it has be sit as undisturbed as possible even when being transferred from one place to the other if you want nice crystals.

Good luck, report back.

(if it doesn't work, you can always add some acetone to crash out the sulfate and recover it without losses - and you're again a bit wiser then... Wink

)

i_a

icecool · Insistent Chemist

IndoleAmine · Dreamreader Deluxe

Brominating amphetamine freebase would lead to neurotoxins.. Shocked

Amphetamine nitrate and acetate can be made, but the nitrate is no pharmacologically accepted salt form (obvious, who would want to ingest nitric acid?). The acetate is possible with GAA/Et2O just like when making EDDA.. Wink

The acetate is less potent when compared by weight, but on a molar basis there's no difference, you just need to adjust the weight to fit the molar amount you're used to with sulfate..

Your acid/base extraction looks correct, and yes you can also use DCM if no solid garbage is sitting at the bottom. Eventually occuring emulsions can be dealt with by vac filtering the two layers through a fine filter, the two phases usually will separate nicely in the filter flask (if not before)...

loki · guinea pig

my thoughts on converting freebases dissolved in nonpolars (well part of it)
http://synthetikal.com/synthforum/viewtopic.php?p=4703#4703

if you happen to know exactly how much freebase alkaloid you have dissolved in there (remember to subtract acid weights if we are discussing a previously in salt form version of the alkaloid) then a standardised molarity solution (work out what molarity concentration to use depending on the accuracy of your volumetric measuring device on hand, combined with the amounts of alkaloid, in moles, that you will likely be using this solution on) will make the whole thing a lot easier, do a bit of math and then you just make up a volume of solution you can accurately measure, containing the number of moles of acid required to ionise the number of moles of alkaloid, agitate with the nonpolar/freebase solution for a minute or two, and then separate and boil off the water (being careful about heat once it starts to get saturated). i developed this method of going from freebase to salt as a result of the fact that concentrated HCl does not seem to readily ionise alkaloids (compared to anhydrous gas or dilute solution). as i mention in that other post it can be used to fairly accurately assay yield with more dilute solutions too.