Author Topic: OTC GHB (FeSO4 & THF + H2O2)  (Read 2683 times)

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Chromic

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OTC GHB (FeSO4 & THF + H2O2)
« on: July 04, 2002, 04:12:00 PM »
After reading Foxy2's reference of JP 53087347 & 19780801, I went ahead and got my dare-devil twin double who fills in for me when I feel a bit worried about performing a reaction to experiment with this reference. I decide for the safety of every one in the immediate area that 1/5 scale would be a moderate test batch. As you can see, my dare devil is to me, what Zwitterion was to Eleusis.

History should have taught me better.

Anyways, on to the chemical story, the dare devil cautiously added 8.1ml (7.2g, 100 mmol) of clear colorless THF (distilled from pipe cement and stored over aqueous brine/bisulfite) and 3.0g (20 mmol) of pale green FeSO4.H2O. Putting this into a water bath at room temperature, he slowly started to drip in 20.4g of 35% H2O2 (7.2g H2O2, 210 mmol). After a few drips were added, the solution went to a dark burgandy red. Say, isn't that the color FeSO4 is supposed to go if there's peroxides forming in the mixture? Oh well! Then it started to boil vigorously. Oh shit! So, the brilliant dare-devil, takes this reaction to an ice-water bath and proceeds to very slowly add all 20.4g of 35% H2O2.

But nothing has happened, no real increase in temperature... what's going on? So, he removes the ice-bath.. and warms it to around 15C. Nothing. Around 20C. Ahh.. it's getting warm, maybe we should put it back in a cold-water bath. So that's done. But that doesn't slow down the reaction, soon, this 30ml mixture is filling the 100ml flask it's in, and climbing a 250mm reflux condenser to shot out the top and spray the ceiling.

Hmm...

The dare devil stops.

The dare devil thinks.

The dare devil vacates the room.


Chromic

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Another boil over?
« Reply #1 on: July 04, 2002, 05:04:00 PM »
After slowly adding 10.2g 35% H2O2 to 4.1ml thf with 1.5g FeSO4 in a water bath, the reaction seemed to go ok. I thought I had won it's heart.  :)

Then towards the end it started to take off... a 600ml beaker filled with 20C water was used for cooling, but I think I should really be using something larger (or moving the water around). This time the arrangement was with the condenser ontop of the addition funnel, so the reaction never climbed up the condenser (and the add funnel slowed down the re-entry of the THF). The water was left around 50C or so. This reaction is very exothermic. Beware!

But... the good news is everything is in the flask, and there might be some hope to work this up!

Elementary

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Straying the ceiling
« Reply #2 on: July 04, 2002, 05:19:00 PM »
I've have to quickly vacate a room then re-enter later with a pot of white mat to re-paint the ceiling, its quite terrifying at the time  :o

Anyway, I need to ask a stupid question (maybe ?). You seem to of taken sensible precautions to avoid peroxide formation with your THF, are you not just asking for trouble by adding hydrogen peroxide the the THF now ?

John Lennon - Working Class Hero

Chromic

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Good question!
« Reply #3 on: July 04, 2002, 05:35:00 PM »
I hope I was? During storage, NaHSO3 is great for removing oxygen and preventing the formation of peroxides (may also decompose them). During the reaction FeSO4 is great for destroying peroxides, perhaps it is also involved in the reaction mechanism.

The workup was continued by extracting 3x10ml of DCM, adding a bit of aqueous FeSO4 and distilling it off. Next off, I think I'm going to add 30ml H2O and distill that. If there's any GBL it will be carried over. I'll report back soon.

Chromic

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Negative on the bioassay
« Reply #4 on: July 04, 2002, 06:53:00 PM »
That reaction should have made a fair amount of GBL (like ~2.5ml). The contents of the reaction were distilled, as said, 1.9g Na2CO3 added, slowly boiled down, acidified to neutral... then drank. I'm not noticeably high. This sucks. Perhaps a more careful slow addition needs to be performed so the reaction never gets out of control. I'm struggling typing here...  perhaps I am a bit buzzed? Nah, likely just tired. Oh well, hopefully my experiences have inspired someone else to give this route a try.

Osmium

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H2O2/Fe(II) is a radical starter, this reaction ...
« Reply #5 on: July 05, 2002, 03:13:00 AM »
H2O2/Fe(II) is a radical starter, this reaction seems to work by a radical mechanism adding OH(.) to the molecule. There really is no need to keep your THF peroxide free, since that reaction creates them anyway.

I'm not fat just horizontally disproportionate.

SPISSHAK

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F.T.F.D.
« Reply #6 on: July 06, 2002, 12:55:00 AM »
Follow the fuckin directions!
Not H2O2, but kMnO4 is the oxidant used here, and there is probably a reason why.
Namely because of the cation the oxygen atoms are bound to.
The difference between a weak oxidizer and a strong one, catch my drift?

Chromic

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Thank you SPISSHAK
« Reply #7 on: July 06, 2002, 05:09:00 AM »
Why, SPISSHAK, I think that's a great idea! Thank you for your advice. I'll try "following the fucking directions" next time.