Author Topic: Xylene vs DCM for MDP2P  (Read 2774 times)

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DiMethyl

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Xylene vs DCM for MDP2P
« on: November 06, 2004, 12:15:00 AM »
One was wondering if xylene could be used in place of DCM for extracting MDP2P from the Benzoquinone Wacker Oxidation of Safrole in Methanol mixture?
Anyone here ever read anything about that?
DiMethyl


ApprenticeCook

  • Guest
NP solvent requried....
« Reply #1 on: November 06, 2004, 05:38:00 AM »
NP solvent requried....

DCM is easier to see from post wacker mix so you can sperate it but any NP will do just as well, make sure you add plenty of NP and agitate, and do several extractions, pool and evap solvent.

-AC


DiMethyl

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Xylene vs DCM for MDP2P
« Reply #2 on: November 07, 2004, 06:50:00 AM »
Well---there are degrees of polarity and degrees of solubility, so things are never as simple as they may appear on the surface.

DiMethyl


ApprenticeCook

  • Guest
thats why i said if you dont use DCM make sure
« Reply #3 on: November 07, 2004, 11:14:00 AM »
thats why i said if you dont use DCM make sure you do several more extraction washes than normal, this will be sure to counteract any solubility differnces....

Why did you ask the question if you already knew the answer?

-AC


DiMethyl

  • Guest
Xylene vs DCM for MDP2P
« Reply #4 on: November 07, 2004, 09:50:00 PM »
I asked the question because I have never seen posted anywhere anything about the solubility of mdp2p in xylene, and I have looked extensively.
Considering the relative chemistries of the respective molecules, it would seem reasonable that xylene would dissolve the ketone.
But then chemistry is complex and I was looking for perhaps some input from someone with some actual experience with this issue.
DiMethyl


indole_amine

  • Guest
DCM vs. Xylene
« Reply #5 on: November 08, 2004, 01:34:00 AM »
DCM is better - it rips the crap out of every aequous solution. But Xylene is a powerful nonpolar, too - just not as miscible with water as DCM, therefore you have to do several extractions (3-5x) with more Xylene (like 3x100ml for extracting 500ml aequous soln.) and probably you'll have to fight emulsions; in contrast to DCM, where 3x65ml would probably suffice to give the same result, with easy separation (I LOVE bottom pullers!  :) ).


indole_amine

ApprenticeCook

  • Guest
I was looking for perhaps some input from...
« Reply #6 on: November 08, 2004, 01:23:00 PM »
I was looking for perhaps some input from someone with some actual experience with this issue
And what is that supposed to mean?
man i told you the answer, DCM is better but xylene will still do the job, but you have to do more extractions, as indole has confirmed what i have said...

I cant speak for indole but as for me that IS coming from someone with exp in the field...

So, just for clarity....
I have so far said:
add plenty of NP and agitate, and do several extractions, pool and evap solvent
and then again:
make sure you do several more extraction washes than normal, this will be sure to counteract any solubility differnces....

Do you need it said AGAIN?

Well here it is....
DCM is better than Xylene (in this case), solubility ratio yes will be different but the main point of DCM's use is to allow easier seperation as (once again) indole has confirmed... if you cant find DCM (and god only knows why not) xylene will do but use more volume of NP and do several more washes and make sure to agitate plenty and let it settle before seperation.

-AC