Bisulfite complex formation isosafrole interfere?

[SPISSHAK]

I UTFSE and was wondering since there is a lot of interest in averting distillation via purifying with sodium bisulfite complex formation procedure.
One of the hindering factors I deduced that makes this impracticable I'm told is the prescence of alkenes (like isosafrole) which interfere with crystallization of the complex.
So SWIM proposes that the procedure be done with a two phase system.
For example: the extract after washing could be mechanically stirred over a saturated solution of sodium bisulfite.
It would seem that the organic phase would chemisorb most of the alkenes which are said to interfere with the complex formation.
Does anyone who has extensive personal expirience with this purification method, have any ideas to add or compliment this proposed modification?
Ancillarilly, a little bird tells me that alcohols are the best means of washing this complex to remove impurities trapped in the matrix.
Can anyone verify this as a service to us no glass havin, broke ass bees?

[Osmium]

Yes, that works pretty well. Shake your ketone or aldehyde containing extraction solvent with bisulfite solution, filter the precipitate and wash with ethanol and ether to remove adhering impurities and you get pretty pure, dry bisulfite adduct. The ether wash isn't really necessary in most cases.
I'm not fat just horizontally disproportionate.

[hCiLdOdUeDn]

Very Nice MaDMAx
Clouds come and go and never stay still........

[Osmium]

60ml Bisulfite sounds like a little too much.
Now add some NP solvent to the impure ketone and try again. I bet it will work better. At least it did for me.
I'm not fat just horizontally disproportionate.

[SPISSHAK]

I've heard a lot of people say that aminations don't work with bisulfite purified ketones.
But I think that the procedure was'nt done properly.
I got to go to the slam tommorow    but I like the way this post turned out.
It will give me some food for thought.

[SPISSHAK]

see what happens when you take that yellow sloppy bisulfite adduct and rinse with a little alcohol.
Or, before you do that, add something nonpolar to the flask with the impure bisulfite adduct and see what happens with a little stirring.

[Chromic]

Osmium, in trying to purify asarone ketone, I found that:

1) it was destroyed by distilling at atmospheric pressure (unlike mdp2p, pmp2p)
2) using the oxime formation as a purification step gives nothing other than a sludge (that aminated!)
3) bisulfite purification doesn't work, as it gives the typical impure chicken fat result that MaDMAx is showing off in the pictures above

Can you please clarify what you mean by add a bit of NP and shake? Are you saying that beautiful bisulfite crystals of tmp2p will form if I add some NP (what would you recommend, DCM, toluene?), aqueous bisulfite, and stir? I notice in other posts you recommend not to use alcohol, did you use it when using a NP?

Thanks.

PS. MaDMAx, I was going to take pictures exactly like yours! Really! I was! I'm just lazy. =) I was going to do it in 3 or 4 test tubes though...

[fierceness]

Has anyone checked to see if the NaI complex works any better?

[SPISSHAK]

ALA osmium via P.M. he get's a little more specific.In reply to:
--------------------------------------------------------------------------------
Are you saying positively without a doubt that the two-phase bisulfite ketone complex procedure works to give nice white fluffy bisulfite addition products?

Yes. I did it myself. Ketone dissolved in several volumes of ether, shaken with saturated bisulfite solution. The whole flask was full of solid precipitate, filtered, washed with bisulfite, EtOH, then ether. Result was dry, slightly yellow bisulfite complex. It works.
 
 
So there you have it folks.
This needs to be expounded I think with a few success and failure tales to verify it's legitimacy.
Coupled with some freezing techniqes thanks to Madmax and others this makes M.D.M.A. without glass a viable possibility (as opposed to the previous collective wisdom of this site), for all the economically disadvantaged or paranoid expirimenters.

[Osmium]

Forgot to mention, bisulfite solution was only water, no alcohol added.
I'm not fat just horizontally disproportionate.

[Chromic]

SPISSHAK, I don't see why you would ask the question in a PM before you'd ask a public message... if you've got a question, more than likely ten other bees have the same question. I had the same question, asked it via the message right above, then directed Os to the post after seeing that I might not get an answer from Os.

Thank you for sharing the PM, but... do you think we could all share this information publically in the future? It would benefit all of us! I hate to think of all of the other useful information that's slipped through, via PMs, into the ether of the internet.

I think there's been another post from the mods on exactly this subject.  

[OB1KNoBee]

Don't try and purify your crude ketone by forming the bisulphite adduct and cleaning it. It doens't work very well at all and it's messy too, believe me it's a bloody waste of time. Just get yourself a vacuum destillation set up B4 even trying these synths. I tried purifying crude ketone with metabisulphite and it was chicken fat central that didn't seem to clean up whatsoever.
  I would just use the rest of your sodium bisulphite in testing for presence of ketone, that's what it's best for.
OB1

[SPISSHAK]

But the point is there can be improvements like the one above that can make the whole thing a lot more convenient.
I take it that you just added crude ketone to a saturated solution of sodium bisulfite without any of these modifications, like dissolving in ether or similar nonpolar solvent, to get the notorious "chicken fat".
Am I correct?

[terbium]

But the point is there can be improvements like the one above that can make the whole thing a lot more convenient.
While it is admirable to want to develop procedures that enable the synthesis of MDMA without the need for a vacuum pump and with the minimum of glassware, the tradeoff will be in poor yields of product. Purification using bisulfite just gives poor recovery of ketone. I experimented with preparing the MDP2P-bisulfite and then regenerating the MDP2P and got poor yields even when I started with pure, distilled MDP2P.

[SPISSHAK]

So where do you think the losses went?
In an incomplete bisulfite adduct precipitation, the washes, etc.?
I guess the question is, obviously the losses were mechanical, so what procedure did you notice gave poor returns?

[terbium]

It has been a long time but I believe that the losses were due to incomplete precipitation of the adduct. I was using the bisulfite prepared according to Vogel with water/methanol. Osmium and others here have used bisulfite solution without any methanol; perhaps that would work better.

[goiterjoe]

Forming the bisulfite wouldn't serve as an alternative to vacuum distillation of ketone, but it could greatly aid in reducing the amount of tar left over in the bottom of the distilling flask from after a peracid/acid hydrolysis reaction.  If you could form the bisulfite complex with quantitative yeilds, followed by cleaning, reclaiming the ketone, and distilling, you would eliminate a large quantity of the tar that is left over even after your caustic ketone washes.  I imagine everyone here hates having to clean glassware, as it means extra time not spent performing reactions.
All paths are the same: they lead nowhere

[Osmium]

My ketone distilling flask cleans itself, simply by standing in a corner of the fume hood with some acetone or alcohol inside for a day or two.
I'm not fat just horizontally disproportionate.

[goiterjoe]

Most bees don't like to have glass out in the open for a day or more, and we also don't like to have acetone evaporating out in the open when we're not there.
All paths are the same: they lead nowhere

[Chromic]

Acetone has always cleaned out the flask in a jiffy for me. I try to never distill the oil so far that it burns... I always remove the heat from the flask when the last of the ketone is coming over...