Author Topic: Quenching Grignard - Holy Shit!  (Read 2666 times)

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Bwiti

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Quenching Grignard - Holy Shit!
« on: December 26, 2001, 06:01:00 AM »
What's up?! A bear in my dreams said, "I reacted a methoxyphenyl Grignard with another interesting chemical and the reaction was hot enough to burn me when I placed my hand on the side of the jar. Good sign! The huge pickle jar was allowed to sit for about 20 hours, then it was time for quenching. I added a bunch of ammonia, water and a little ammonium chloride to it. It immediately got hot, then I had to bring it down to my basement, because it started to boil! I used excess Mg in my Grignard, so is that the reason for it being at a pissed off, violent boil? Can all this heat ruin my legal analogue? The bastard's been boiling for about 20 minutes now! I put a ceramic pot under it that's designed for ovens just in case the jar breaks. It just makes me nervous when I can't control a reaction. I thought about dumping all of it into a 10 gallon bucket and overwhelming it with water, but I'm worried that the solvents in the reaction mixture will dissolve the plastic. Help! 

  Love my country. Fear my government.

PrimoPyro

  • Guest
Re: Quenching Grignard - Holy Shit!
« Reply #1 on: December 26, 2001, 06:04:00 AM »
Have you tried putting it inside dry ice/acetone bath?

That will suck a LOT of energy out of that reaction, especially if its a small container. It should stop the boiling, and may even make the reaction stop altogether!

Hell, just try a normal ice bath first and see what happens!

                                                 PrimoPyro

Vivent Longtemps la Ruche!

Bwiti

  • Guest
Re: Quenching Grignard - Holy Shit!
« Reply #2 on: December 26, 2001, 06:09:00 AM »
No dry ice, but I do have some acetone..I would put it in an ice bath, but if the jar broke, it would spill everwhere.. I have to find a large pail. Peace!

  Love my country. Fear my government.

Bwiti

  • Guest
Re: Quenching Grignard - Holy Shit!
« Reply #3 on: December 26, 2001, 06:24:00 AM »
I put on my oven mitts and put the jar into a mop bucket, then I added very cold water. I was gonna go up to the 7-11 and buy a bag of ice, but the cold water is working well by itself. I'm surprised the jar didn't crack. I'm using a ceramic plate as a cover for the jar. I opened it for a second, and all I could see was boiling grey matter. A little chem/water vapor hit me in the face when I opened it, and now I'm feeling a little altered!
  When the chems are finished reacting, I need to separate the non-polar toluene, product, ether from the water and slop. Usually, I sprinkle sodium chloride into it until two distinct layers form, but I have a problem, because the salt I have is fucking iodized. How can I remove this shit from the salt? I'll just use TFSE to find other ways to bust up emulsions.
Peace and happy cooking! 8)

  Love my country. Fear my government.

PrimoPyro

  • Guest
Re: Quenching Grignard - Holy Shit!
« Reply #4 on: December 26, 2001, 04:32:00 PM »
Go buy non-iodized salt from the grocery store, and while you're there, pick up a ten lb bag of ice.

Both kinds of salt cost the same $2.25, and they are in the exact sae spot in the store. Some people cannot eat iodized salt, so straight NaCl is so common.

                                                  PrimoPyro

Vivent Longtemps la Ruche!

Osmium

  • Guest
Re: Quenching Grignard - Holy Shit!
« Reply #5 on: December 26, 2001, 08:39:00 PM »
Arrrgh!
Iodized salt contains about 0.003% KIO3! What the fuck is the problem?!? Just use it dammit!

Bwiti

  • Guest
Re: Quenching Grignard - Holy Shit!
« Reply #6 on: December 26, 2001, 10:04:00 PM »
"0.003%"

  That's all? Thanks! 8)

  Love my country. Fear my government.

PolytheneSam

  • Guest
Re: Quenching Grignard - Holy Shit!
« Reply #7 on: December 27, 2001, 12:36:00 AM »
When I was doing Grignard reactions in school (college) we were told to use a bucket of ice water to cool the reaction flask if needed.  I found I needed ice with some Grignards at home, too.  Ice always worked with the reactions I did (phenyl magnesium bromide and benzyl magnesium chloride).

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Bwiti

  • Guest
Re: Quenching Grignard - Holy Shit!
« Reply #8 on: December 28, 2001, 01:43:00 AM »
My product was ruined, but at least I've mastered the initiation of Grignards.

  Love my country. Fear my government.