wired 80% acetic acid

[noche]

I have some things about the peracetic acid oxidation  I have ben thinking about for the last coupels of days.
The first thing is the glacical acetic acid used in the reactiion: does it  HAVE to be 99-100% acetic acid or will 80% be able to do the job? if so I asume that it will affect the yeld.
The reason why I ask this question is that when freeze seperation was attempted in order to seperate out the remaing 20% water, the acetic acid was suposed to freeze out and the water wich was still liquid was to be  poured of. I beleave a temperature of 3 dec C  (a guess)  would be preffered to insure god preciptation of the the acetic acid. but the wired thing that happenend was that even  after 2 days in the fridge the 80% acetic acid was still liqiuid. The same amount 30% acetic acid was  completly frozen after only one day.
So.. what is wrong with this wired 80% acetic acid? could it be contaminated with something that would prevent it from freezing (It DOES say chemical pure 80% acetic acid in demineralized water). Or could there be an other explanation like I am going mad or something?
alternativly I was thinkinng of removing the last 20% of water by refluxing a 50/50% mix of 80% acetic acid in acetone with anhydraus MgSO4 and then later cool it down to -10 deg C in order to freeze out the MgSO4 holding the water and then finaly destiling of the acetone to leave one with glacical acetic acid.
 
 

[Chromic]

80% acetic acid is fine for a peracetic oxidation.

(I recommend doing a peracetic epoxidation in DCM, and make sure you let the hydrogen peroxide and acetic acid stir with sulfuric acid for a few days)

[goiterjoe]

send it to Afghanistan.  there are plenty of people over there that know what to do with it.
If Pacman had influenced us, we'd run around dark rooms eating pills and listen to repetitive music

[Chromic]

As in anhydrous acetic acid? Or acetic anhydride?

GJ, do you know a way of using anhydrous acetic acid in that sort of procedure? (ie glacial acetic acid?) I'd love to hear some details, I've only heard of acetic anhydride and acetyl chloride being used for that purpose.

HoH, I'd hang onto it. Who knows, your direction may change in the future... GAA is a handy chemical to have around.

[goiterjoe]

I was under the impression that GAA could acetylenate morphine if given enough time, but I've never tried it.  Otherwise, I think you can make acetic anhydride from GAA relatively easily.
If Pacman had influenced us, we'd run around dark rooms eating pills and listen to repetitive music

[Chromic]

Damn, I hoped you had a tried and true procedure. Ketene synthesis looks to be the best way for Ac2O and it doesn't look easy.