Dude, where's my freebase!!

Friendlycat · Wed Aug 17, 2005 10:51 am

Swim ran a Al/Hg with 44g P2P and got 86% yield freebase after acid/base.

A few days later swim ran another Al/Hg with 50g P2P and got 16g freebase after
toluene extraction. Where's the other 35 or so grams? The only thing that swim did differently is use 10% NaHCO3 for the washes instead of 5% NaOH. So where did all that oil go? Did it go out with the wash? Why?

Regards,
FC

Bushroot · Wed Aug 17, 2005 8:27 pm

maybe I'll be beaten with rotten tomatoes but -
the aluminium sludge may somehow hold the freebase!

I had the same problem with Al/Hg reduction of P2NP (7g) -
after basifying the reaction mix, the upper layer was very thin. I poured it off, and as i ran out of diethyl ether I extracted the reaction mix three times with 100 ml benzene. (I did not mix the upper layer and the extracts) Then I acidified benzene extracts with dry HCl - and lost my jaw, when i saw no crystalls falling at all, and the pH was near 4! And the reaction mix with AL sludge still smelled amphetamine base!
I now believe that extracting amines with aromatics from Al\Hg is worthless, so I use ether or methylene chloride...

icecool · Insistent Chemist

Hmm never heard about that, but you could be true.
SWIM also get quite low yields from Al/Hg reductions, but SWIM thought it was because of the Al foil method that something went wrong there, too thin or something like that...
But DCM is fucked up for Al/Hg reactions because the Al sludge goes to the bottom too, and lately SWIM tried to filtrate the Al sludge over a coffee filter in a buchner.
Well after a few seconds the whole filter is clogged up and well it doesn't work well....
I've heard about washing the Al sludge with MeOH to flush out the amine...
Anyway SWIM prefers toluene over ether since it doesn't stink that much and is less volatile and safer etc.

hAzzBEEn · Thu Aug 18, 2005 12:10 am

I think that that Bushroot was implying that toluene is not a good solvent for the Al/Hg because it is an aromatic solvent.

icecool · Insistent Chemist

I know what aromatic solvents are....
And I know what he ment that aromatic solvents are not good to extract Al/Hg reactions with...
I just gave my opinion...

Radiumhero · Thu Aug 18, 2005 11:15 pm

dont know what exactly happens to the freebase when exposed longer times
to those black to grey aluminium sludges but when u let it settle down
and look at the fine pores and the bulked up volume on can figure out that this is able to hold some of the freebase perhaps similar to activated carbon holdin gasses , but i somehow think its not just that , that those al/hg reductions yield
less product with P2P (esp P2NP) than with methoxylated p2ps .

Bushroot · Fri Aug 19, 2005 2:04 am

biobrew · Fri Aug 19, 2005 2:37 am

SWIBB has had no problem xtracting and getting good yields with xylenes, but swibb does use excess solvents when extracting no matter what. So the effectiveness is not quite known. However, swibb is in debate whether or not it's good for gassing.

Also, SWIBB LOVES using 1micron glass fiber filter paper for filtering the Al sludge. No clogging at ALL!!!

icecool · Insistent Chemist

Hmm that´s very interesting, because coffeefilters get clogged after a few seconds.
Where can SWIM get this glass fiber filter paper?
And about where freebase goes...
You should do this.
Add toluene to the mixture after you added NaOH and the pH is >14
Then put the magnetic stirrer on max. and let it stirr for 15minutes or so.
Then let it settle until you have 3 layers, the Al sludge the aquaous layer and the toluene layer.
Decant everything until there only is Al sludge on the bottom of the flask, add MeOH to it and add toluene to it, the MeOH is being used too losen it up, and then boil the MeOH for 10minutes and stir on max, then decant again and do this 2 or 3 times.
Then you're sure that no freebase is in the Al sludge anymore since it can hold A LOT...

biobrew · Fri Aug 19, 2005 3:52 am

https://www1.fishersci.com/Coupon?cid=1328&gid=108437

sorry i guess it was <3micron

Radiumhero · Fri Aug 19, 2005 2:23 pm

Well another way is to fill ur coffee filter with fine sand this helps to filter out the greater particlet and the coffe filter does the rest , however there are two disadvantages , ur coffee filter can break durin filtering , and a loss of substance
due to the ads. @ the sand ... ( sand must be washed )

biobrew · Sat Aug 20, 2005 1:13 am

I saw that somewhere around here that someone suggested celite, but didn't know where to get it. SWIM ordered a FREEE SAMPLE!!!!!. fOUR DIDFFERENT TYPES AND ENOUGH to last swim a life time of semi-micro use. If any bees live around lompoc (aka lompton), you should know where mountains of the stuff is...literally.

hAzzBEEn · Sat Aug 20, 2005 9:43 pm

Bushroot · Thu Aug 25, 2005 8:55 pm

well that's great about xylene, encourages me to buy it and try in a next run!
The last time I used ethylacetate - it's partially hydrolized in high alkaline solution, but only if solution is hot (after basifying). Extracts well and there's no need to use a big excess... Well that doesn't matter cause you always can distill the solvent and use it again, I just don't like to do the extra work...

hAzzBEEn · Thu Aug 25, 2005 11:33 pm