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DMF Wacker --> Problem

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DiethylEtherMan:

OK. As you all know I attempted a DMF Wacker and got 430g supposed ketone. Well actually, during the frac distill of the ketone I actually only got 400g...then broke it down when nothing left was comming over and distilled without frac...and got 30g more...along with some safflower oil I think...(stupid me)...but I could see some contaimination in there....maybe even some pdcl2 (black gritty shit)...who knows...anyway that night I attempted a 2.5x al/hg which for me always goes like this: 75g al, 700mg hgcl2, 70g ketone, 50ml nitro, and 100ml meoh....addition always between 10-13 minutes and refluxing for 3 hours with typical workup at the end.

1) (Which was before 2.5x al/hg mentioned above) On this particular occasion (after the DMF) I only had 40g ketone from benzo...so I added the 30g contaiminated ketone, just to see how it would fair. Afforded me with 54g xtals....not bad I thought...although during gassing...a nasty reddish blob formed in the toulene (kinda like a thick booga)...attached to the gassing rod...eventually fell off and just stuck in the toulene....and even after that...xtals where still white and looked fine. So, I didn't think much of it...although, I did remember seeing, during the NaOH drench....a nasty brown layer...always right on top of the vortex when mixing and basifying (BTW, I basify in the same 5L flask I do my reaction in...while stirring, and then dump into sep for extraction...this seems to work well for me)...and if I stopped the stirring the brown gunk/oil...would just sit on top....I noticed this in the next two reactions...

2) (this is the 2.5x al/hg mentioned above) Next attempt at 2.5x al/hg....with 70g supposed ketone from DMF wacker. OK. This one was setup exactly the same as the last...the only difference is that I brought the MeOH/HgCl2 to a slight boil, then dumped in al....which did its thing immediately...everything else was the same except I cut the reflux time to 2.5 hours. I have been reading the hive and seen people state that the reflux time can be reduced when first boiling the MeOH/HgCl2...Well, anyway...I will stick to the usually method...I do not like that..not now anyway...SO...Again, the nasty brown crap during Basifying...this time seemed like there was more (BTW, I have never remembered seeing a brown color during al/hg with benzo tone)....Also, toulene seemed to have a yellow tint (as did the tone from the DMF wacker)...and as did the washes....so I washed 6 times to try and rid the mixture of the yellow color...and it seemed to do the job....so, this is the bum-fuck....gassed and the fucking solution turned yellow...and then orange (probably over acidifying)...and at first didn't see much xtals...then as it settled I noticed there were in fact some in there....filtered and dried to end up with 19g of orange xtals ...yes...orange...I have to get some acetone before I can re-xtalize.

At this point I knew something was up with the Wacker tone...for sure. So, I took the tone I had left and re-distilled....between 100-104C I got a butt load of slightly yellow oil....which I thought was safrole, but when I think back, my safrole seems to come over somewhere between 70-90C...then, within the blink of an eye...the temp jumped to 115C...I let it run for a few secs and then changed flasks...everything stopped coming over at 122C...which seemed correct for the benzo tone I had distilled...afforded me with (first fraction) 259g....(2nd fraction) 97g.

3) So, tonight I attempted another with the re-distilled wacker tone. NOW this is there real mind fuck...check this out....Start the reaction as usual. During basifying..I see the brown shit again....decide this time, to put in sep and separate the brown booga shit...done..xtract as usual...again the toulene has a slight yellow color to it....wash a couple xtra times and toulene looks clear...dry and I was going to wait until tommorrow to gas...but said fuck it...I will try a little bit just to see what is going to happen...so, out of the 1800ml toulene/product I had sitting in a 2L beaker with mag sulfate....I took 400ml filtered and gassed...."FUCK" ...not as bad as before...but I ended up with some slightly yellow xtals...toulene turned yellow too...I haven't dried them yet, but looks like maybe 8-10g.....THEN (now here it is)...I said fuck it, the gassing generator is already set-up...and I gas the rest of the toulene....and low and behold....snow white xtals....a buttload of them too....looks like the right amount that I usually get...3 coffee filter loads... Now just for the fuck of it...I filter the xtals...and allow the filtering toulene to be filtered into the toulene that came from the yellow xtals (which was now fairly clear)....only cause I wanted to see if maybe it was something in the gassing set-up...like some acid in the gassing line or some shit...but nope....bang, another small load of xtals...this time...they are orange again....like in the #2 attempt (which is probably the yellow xtals plus overacidification..yellow/red make orange...right...

So, you tell me what the fuck is going on here....? Is it possible that when I dumped that 400ml of toulene into a seperate beaker that it carried with it ALL of the contaimination? I mean, how the fuck am I ending up with some contaiminated xtals...then snow fucking white xtals?

I can see kind of what happened here. In the 1st attempt...I used the supposed tone from a DMF....but the 30g I used was from the last bits of my distillation (broke down a frac distill setup which gave me 400g tone...to a regular distilled setup which afforded me another 30g tone which was used here)...so it was def tone...with no safrole...although there was some safflower in it...and maybe some pdcl2 or hydroquinone...and thats what probably caused that brown booga shit during basifying...but still gave me good yields..just a little reddish booga shit (a small reddish booga blob while gassing that didn't effect yield or color).
Then, on the second attempt...I used what I thought was ketone but was actually probably safrole/ketone mix..at a ratio that would coincide with the yield I got...18g xtals from 70g supposed ketone (according to my math)....so this attempt is sort of understandable...
BUT...the third attempt....re-distilled ketone...Same brown booga crap during basifying...and two different color xtals from the same toulene xtractions....? What gives?

Is that shit weird or what? Is it possible that the first 400ml toulene that I filtered and gassed carried with it all contaiminents??? I doubt it...

it's got me...thats for sure...

How about water in the solution? Would that make yellow xtals?

Does anybody want to make an attempt at explaining this (yellow xtals then white xtals from the same toulene)?

peace.

DEM

The quality of every man's life has got to be a full measure of that man's personal commitment to excellence and to victory, regardless of what field he may be in. --> Vince Lombardi

If some of us were not so far ahead, the rest of you would not be so far behind!

noj:
The only part I could answer is that if there was water, your crystals would be redissolved back into solution. Does that orange come off with an acetone wash? If yes, then it sounds like too much acid, but the product is still good. Crystals I get are slightly brown though, which washes off nicely.

An optimist thinks this is the best possible world.
A pessimist fears this is true.

DiethylEtherMan:
Noj...wassup buddy!

Well, I have come to the conclusion that some fucked up shit happened when making the tone (from DMF o2 Wacker)...thats what I think. Cause I have been bangin out 2.5x and 3x al/hg for a while now...with no problems and always with a 50-55 (or whatever) gram yield....always snow white..unless I gassed a 2nd or third time...then would get pink xtals...(always using the tone from benzo)....

This yield was as follows:

the first gassing of the 400ml of toulene I filtered and gassed: 6.5g which where slightly yellow (could've been from too quick of a gassing, cause, yes, I had the generator really pumping..

Then from gassing the remaining 1400ml toulene...got a total of 24g snow white xtals.

Then...when mixing both batches of toulene (1400ml and 400ml) and gassing again...ended up with 5.5g of a nasty deep orange xtals...

A total of 36g of shit xtals (except for the 2nd gassing)....which is horrible for me. I always...and I mean that every time I have done al/hg gotten 80-85% (not molar) yield. EVERYTIME!

Plus not to mention that brown booga shit during basifying...never saw that before....

Being that my memory is back....I also think that in the DMF supposed ketone...I think was contaiminated with something in between the safrole and ketone (maybe contaiminated is a bad word)...I am not a chemist, but I remember hearing about the safrole turning into an amine first or some shit...the only reason why I think this is so is becuase my safrole comes over between 70-90C (depending on volume of oil in pump)...and ketone usually comes over between 115-125C....so that huge fraction I got between 100-104C must have been something else...? Anyway...I will attempt one more small DMF O2 Wacker and give results then...in the meantime...benzo hear I come. Ooo, I hate this reaction.

peace.

DEM

No facts are to me sacred; none are profane; I simply experiment, an endless seeker with no Past at my back. --> Raplh Waldo Emerson


If some of us were not so far ahead, the rest of you would not be so far behind!

Osmium:
Don't rely on distillation temps too much. It's not uncommon for the vacuum to get worse after some time. When your safrole distilled at 80°C with your pump then this pump is too strong. Sassy contains lower boiling components, and at that vacuum your pump oil will be contaminated with that lower boiling shit. Same with the solvents you use and remove by distillation. SOme of them will end up in your pump oil. Seems like your pump is running pretty consistent now, with safrole boiling above 100°C, so I recomment don't change the pump oil, but keep it running with the inlet closed for some time (30 mins-1h) before and after the distillation so the pump can clean itself. If there is a small valve somewhere on your pump so it will draw in some air while it's running, ALWAYS keep that small valve open. This so-called gas ballast causes your pump to run louder and with a slightly reduced vacuum, but it also keeps your pump oil cleaner.

Ketone is yellow, so when something comes over and it's nearly colourless or only slightly colored it can't be ketone. Logic dictates it must be safrole or isosafrole. your ketone will always be the second fraction during distillation, the amount of the first fraction depending on how big the conversion was.

After your Al/Hg, DO A FUCKING A/B!!!
Crystallising clean freebase works every time, crystallising dirty freebase gives you nothing but headaches.
Dissolve your crude freebase in diluted HCl, check pH to assure it's acidic. Then wash this solution 2-3 times with toluene or DCM or any other non-polar organic solvent. This wash can be discarded, but I suggest you evaporate at least some of it to see the crap you used to leave in your honey! The acidic water solution is then basified with strong NaOH, which kicks the freebase out of solution again. Extract it with your solvent of choice and gas. I assure you that you will encounter much less problems and a much cleaner product this way.

DiethylEtherMan:
Os, I totally understand what you saying about the A/B. But the the only reason why I haven't is because when using benzo tone...I have never had this problem. Only since I have been using this DMF wacker tone has my xtalizing been kicking me in the ass....with benzo tone, have always gotten 50-55g xtals...snow white (2.5x al/hg)....So, I can't figure it out about the DMF wacker....maybe I did actually add that overdose of h20??

Will try again soon!

peace.

DEM

(no quote)

If some of us were not so far ahead, the rest of you would not be so far behind!

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