extracting PPA from pills with acetamenophen?

geezmeister · Busy Bee

My friend SWIG dropped by with a supply of rather old OTC pills that contain Phenylpropanolamine and Acetamenophen/paracetamol. The pills are noted as some that are of a brand that were not particuarly gakked, and these are at least four years old as they were for sale OTC when PPA was pulled from the store shelves in America in 2001.

Thus far the best procedure he has devised to separate the PPA seems to be dissolving the PPA and acetamenophen in warm water, filtering out the pill solids, chilling the water to near freezing, filtering out any precipitants, and evapping the water for the PPA. Then he would likely need to redissolve the precipitants in cold water several times, and do several evaps to get as much of the PPA as he can. He realizes he may need to redissolve all the obtained extract and repeat the process to get it even cleaner.

He realizes the PPA is an amine, but also recognizes both are amino alcohols. He doubts the efficacy of an a/b extraction, but his chemistry knowledge is pretty limited to being a decent pill cook and he's guessing here.

Any suggestions on helping him get the PPA separated from the acetamenophen so he try his hand with 4MAR would be very much appreciated.

geezmeister · Busy Bee

This information has been obtained:

Physical Properties
Molecular Formula : C8H 9NO2
Molecular weight : 151.17
Chemical name : N-(4-hydroxyphenyl)acetamide
properties : White crystal or Crystalline powder. Non smell. Taste is slightly bitter.
melting point : 169-172c
log P : 0.51 ( Experimentally determined value ) 0.49 ( Calculated value )
Ionization Constant @pKa : 9.71
Solubility
acetone : easily soluble
ether,benzene : hardly soluble
Saturated solution : slight acidity

Sounds like acetone might just be the magic bullet. I have not worked with acetamenophen/pseudo tabs before, and do not recall reading anywhere that acetamenophen was acetone soluble. Seems like a wash should take care of it.

SWIG will no doubt tell me if he succeeds, and I will relay the information to the board.

bio · Working Bee

Maybe this will help.

p-acetamidophenol (INN); acetaminophen; N-acetyl-4-aminophenol; APAP; 4-hydroxyacetanilide; Tylenol (Johnson
& Johnson); [103-90-2]

C8H9N1O2 (151.17). White, crystalline solid. MP: 170°C.
d: 1.29 kg/l (20°C). Soluble in hot water, oxygenated
and chlorinated solvents.

loki · guinea pig

it's quite likely if apap is soluble in chlorinated solvents and in acetone that it would also wash out with ethyl acetate too, the EtAc would have to be dry of course (same goes for ketones or chlorinated hydrocarbons). APAP is not very soluble in cold water either. Next time i play with some apap-contaminated pills i'm gonna try a dry TCE or acetone wash.

geezmeister · Busy Bee

Glad to have the information on the chlorinated solvents. Might be that the TCE wash has real utility for a change.

loki · guinea pig

i missed the bit where it says 'oxygenated and chlorinated solvents'...what's an oxygenated solvent? ketone? ether? my money is on ketone.

Vitriodor · Sat Jul 02, 2005 4:10 am

loki · guinea pig

a little vague then...

dwarfer · Thu Jul 14, 2005 4:02 am