Sciencemadness Discussion Board

Sodium 4-Aminophenolate

Stearic - 6-7-2013 at 01:00

I would believe that hydrolysis of acetyl p-aminophenol(tylenol) with Sodium hydroxide would produce acetic acid and sodium 4-aminophenolate. Could you then precipitate copper 4-Aminophenolate?

sargent1015 - 6-7-2013 at 05:57

Oh dear god, now I understand why Nicodem gets pissed off at these posts.

Where are your sources???

But, anyways, since I have nothing better to do, I will spoon feed you some information.

Yes, you can hydrolyze the acetyl amide, either with acid or base
This paper claims acid hydrolysis works the best, but their formula is wrong, since acid will protonate the amine post-hydrolysis:
http://www.rsc.org/learn-chemistry/content/filerepository/CM...

After that step, I would attempt extraction with saturated bicarb solution and an organic solvent (DCM) as this should leave the 4-aminophenol neutral and extractable into the organic phase. I don't really want to do anymore research for you on pKa's, since I'm sure you can do that and figure out the pH you need to obtain.

As for copper phenolate, one would use a hydroxide in water to get the pH below 10 (If you looked up pKa's, this will be obvious why) and add a suitable copper salt. I have no idea if this compound is stable and isolatable, but I'm sure you can do a little bit more research without my hand holding.

In the future, no references = "Beginnings" section.

sargent1015 - 10-7-2013 at 05:06

Quote: Originally posted by shagydeep  
Hello,
No you need to add black copper and zink in that...


Hello,
please provide a source to your nonsense or do not post.

Or maybe you didn't read my above reaming for Stearic? In which case, please read the whole thread before you post.

bbartlog - 10-7-2013 at 07:30

The pKa of 4-aminophenol is lower than that of phenol, so forming a copper salt seems more plausible than it would be for phenol itself. I would suggest performing the hydrolysis of acetaminophen in acid solution just because 4-aminophenol (like phenols generally) is really prone to air oxidation in basic solution. If you do decide to go with NaOH, make sure to exclude air to the extent possible.



ScienceSquirrel - 10-7-2013 at 08:07

I tried this a long time ago.
Extract paracetamol tablets with say a 50 : 50 mixture of ethanol and water, add about two to three times the required amount of hydrochloric acid and bring to the boil. The smell of acetic acid is immediately apparent.
Cool and crystals of the aminophenol hydrochloride will precipitate as needles.
Adding the crystals to a dilute solution of sodium hydroxide forms a solution of the sodium aminophenolate which is oxygen sensitive, the solution rapidly turns brown and then black depending on concentration.