Author Topic: Old MeOH  (Read 1425 times)

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Vibrating_Lights

  • Guest
Old MeOH
« on: July 26, 2002, 02:00:00 AM »
Swim has come across some old bottles of h**t.  They were bottled in 96.  Swim says that the old MeOH has a stronger and more pungent fishy smell to it.  When compared to a new bottle Of h**t.  This will provide a good test to how the  new additave affects amination yeilds.  So far swims best yeilds have come from a 50/50 mix of EtOH/MeOH. When a 50/50 mix is used the toulene is not miscable with the alcohol. The question though is is it at all possible that the MeOH went bad in 6 yrs. there is definatly a different smell to it.  Batches with straight H**t have never  yeilded what they were supposed to.
VL_

goiterjoe

  • Guest
I think we talked about amination yields before
« Reply #1 on: July 26, 2002, 03:24:00 AM »
You think there is something in your methanol that is messing up your amination yields?  I guess it's possible, but I doubt anyone is adding anything to the H&&T intentionally to mess it up.  I've had no problems with recently acquired yellow bottles.  You say your best yields have come from using a mixture of methanol and ethanol.  I imagine the ethanol you were using was of the 95% alcohol/ 5% water grain alcohol variety.  Have you tried adding any water to your reaction?  Try it next time.  You might be having a problem with not enough water in the reaction to allow it to complete.  It will run a hell of a lot hotter when you add water to it, so be forewarned.  I imagine the runs you did with an ethanol/methanol mixture ran a lot hotter than the straight methanol reactions.

All paths are the same: they lead nowhere

Precursor2112

  • Guest
There is something added to the methonal
« Reply #2 on: July 26, 2002, 01:04:00 PM »
NO time to detain but I saw an amination stop dead. When some h**t contaminated labware was added to cover a reflux...

stop and the foil stopped burning...

Now I'm a distill all reagents type guy.

Diversion?  What diversion?  To who?  To where?  What were we talking about again?

dr_ruthenium

  • Guest
Even distilled fuel line dryer MeOH as solvent ...
« Reply #3 on: July 27, 2002, 05:06:00 PM »
Even distilled fuel line dryer MeOH as solvent resulted in amination failure (orange xylene extracts).  Try MeOH fuel, from local drag strip.

TRISMUS!!!

BenWiFFen

  • Guest
4 what
« Reply #4 on: July 27, 2002, 08:16:00 PM »
What are you doing with it? P/fed pulls or re/x? Or cleaning your MB's

Help i'm a Rock.  Frank Z

goiterjoe

  • Guest
time to look somewhere else
« Reply #5 on: July 27, 2002, 09:28:00 PM »
Sounds like the methanol isn't your problem.  If you're not getting proper yeilds, you're probably fucking something up in the ketone formation.  Drop back another step and look again.  What color is your ketone?  Pale Yellow?  Does it smell like burnt potpouri?

All paths are the same: they lead nowhere

goiterjoe

  • Guest
fractional distillation
« Reply #6 on: July 27, 2002, 10:32:00 PM »
Are you using a fractionating column when you distill ketone to make sure what you are measuring out is indeed pure?  Are you collecting foreruns properly?

All paths are the same: they lead nowhere

terbium

  • Guest
Somewhere else.
« Reply #7 on: July 27, 2002, 11:53:00 PM »
Sounds like the methanol isn't your problem.  If you're not getting proper yeilds, you're probably fucking something up in the ketone formation.
Yeah, as I listen to Dr_Ruthenium's litany of woes in the amination I keep thinkiing the same thing - that maybe she doesn't even have good ketone.

dr_ruthenium

  • Guest
Since switching to fuel MeOH (keeping all other ...
« Reply #8 on: July 28, 2002, 03:57:00 PM »
Since switching to fuel MeOH (keeping all other variables constant), aminations are a success (clear xylene extracts).  Distilled freebase tastes terrible, but lift-offs are a sight to beehold!!!  Next, will distill MDA freebase from Leuckart.  Just needed a 2 stage vacuum to pull to 10 torr.

TRISMUS!!!