The Hive > Methods Discourse
DMF Wacker --> Problem
DiethylEtherMan:
When I finished with DMF wacker...I knew something didn't smell right, but decided to give it a whirl in a 2.5x al/hg and ended up after gassing...with this yellow solution...and yellow nasty crap collecting on the bottom of that beaker and on the dispersion tube...not much...but just a nasty yellow gooey semi-solid...kinda like a juicy booga or something...
Anyway here is the reaction I tried if anyone can see something I did wrong, please comment...also, if anyone has any comments on what to do with the yellow crap/toulene mixture...let me know PLEASE...? Maybe an A/B? I have heard/read of many bee's attempting wackers...swearing they had ketone...than after an al/hg...got nothing.
Here goes:
1) In a 4L Filtering Flask placed 1150ml DMF, 7.5g of pdcl2, 41.25g of CuCl, and 170ml of dH2O. I let this stir uncapped on high for 3 hours.
2) Added 750g safrole. Capped up with rubber stopper and large wire ties...along with a little duct tape.
3) Attached o2 tank with high pressure hose to vac adapter and purged vessel 3x. Pressurized to 33 psi and turned stirring on high.
4) At this point I cannot say how much pressure dropped in total becuase of the fact that half way through I found a small leak. But I was checking it every 20 min and the pressure seemed to drop dramitically every time, until the end. Within one hour the flask was certainly warm...and within 2 hours was hot. Here's where I may created a problem...at the 220min mark...I fell asleep...stupid me...and when I awoke 7 hours later...all the pressure was gone from the flask. Could this have been a problem?
5) Added 1250ml 5% HCI solution...let oil fall to the bottom.
6) Extracted mixture (without sep raw oil first) 3x with 250ml DCM.
7) Washed DCM extracts 2x w/750ml NaBicarb
8) Washed DCM extracts 1x w/750ml NaCl
9) Dried DCM with 140g of mag sulfate
10) Filtered and distill DCM
11) Frac Distilled ketone. Between 100-130C I got what I thought was ketone. And I know that is a large gap in between temp, but there was really no noticeable fluid change...I imagine this could be another problem, right? I will frac distill what I have left to see if I do, for sure, get two fractions. BTW, I ended up with 430g supposed ketone.
NOTE: Another thing I noticed while reading from my Notebook...is where I noted that I added the water in the beginning of this synth, I (in the notebook) wrote down 670ml...which would have been what was required in a 3kg DMF Wacker (per LT)...but I do not think that I would have been that careless to add that much water, I knew that the amount was small (167.25 ml)...although, anything is possible. I have a habit of writing down steps before they are completed. So, with that, what would have happened if I actually did add that overdose of water?
Thanx in advance.
peace.
DEM
There is always a best way of doing everything, even if it be to boil an egg. --> Raplh Waldo Emerson
If some of us were not so far ahead, the rest of you would not be so far behind!
DiethylEtherMan:
Checking the gassed toulene/product/junk again....I noticed that many xtals have tried to form. In fact, alot of xtals have formed. Only they are yellow. Very yellow...along with the solution itself which is a yellowish/orange color...and the ph is somewhere around 2-3.
So, I imagine that my problem my lay in the huge gap of temp when trying to fract distill the ketone...correct?
I mean, if it was that I added too much water in the beginning...I probably wouldn't have got any ketone and no xtals...? But WTF do I know...
Also, I would like to note that the supposed ketone from the DMF wacker has a hint of yellow in it. and smells faintly of sassafras/safrole.
Yes, checked again...and there is a buttload of xtals in there...just contaiminated to all hell with this nasty yellow junk.
peace.
DEM
It's but little good you'll do watering last years crops. --> Dr. Frederic Loomix
If some of us were not so far ahead, the rest of you would not be so far behind!
DiethylEtherMan:
OK. Here's how everything turned out. First, dried and weighed the contaiminated xtals to get 18g...yuck. Orange xtals...only slightly, but they are not the color xtals I would want to take. So, I will re-xtalize tommorrow when I can get some more acetone.
Secondly, I re-distilled that supposed ketone mixture. Being sure to pay close attention to a difference in fractions. Well, there certainly was one...and a quick change too. Could barely catch it.
Between approx. 100-110C got a huge fraction (which would almost signify safrole with my vac, although when re-checking recent notes...safrole usually comes over sooner than that...could this fraction be something other that safrole with a higher boiling point? I do not keep old notes so I only have one benzo synth where I noted safrole distilling at approx 80C) which yielded 259g...turned my head for a sec and the temp shot up to 115C...which I let go for about 30sec to make sure no more safrole was comming over. Then, I changed flasks. And between 115C-122C I got a slightly yellower..thicker fraction that weighed in at 97g. The first fraction was more like a tan...or a hint of yellow, while the second was a deeper yellow...and seemed to be a little thicker maybe. Was slower going down the condenser, if that means anything. And the second sure smelled alot like ketone.
So, starting out I had 430g of supposed ketone. Distilled again to afford me with 97g ketone, and 259g of safrole (I think)...which equals 356g. Plus the 70g of ketone/safrole I used in a 2.5x al/hg..equals 426g...minus four grams in the condenser/boiling flask.
And when I do the math (not in moles, cause I have no clue about that shit) which would be:
I was looking for 50g xtals after re-xtalizing my 2.5x al/hg...and only got 18g (before re-xtalizing) which will probably turn out to be 10-15g I imagine being as contaiminated as it is. Which would be a yield of 20-30%...which is very close to the ratio of ketone to safrole that I had. (ie. started with 430g, used 70g in al/hg...left with 360g ketone/safrole...re-distilled to get 97g ketone...hence, 97g/360g = 27%....27% of 50g (suspected yield from 2.5x al/hg) is 13.5g.
But who gives a fuck about that. What the hell happened in my DMF wacker? How the hell did I only get approx 115g (97g re-distilled and 18g used in al/hg (26% of 70g ketone/safrole)) of ketone from 750ml of distilled sassy? Anyone?
That sucks. I thought I had a good thing going with that DMF wacker. I will try a smaller scale and pay closer attention to O2 absorbtion and that water addition.
anyway, peace. Sorry for all the posts...
DEM
When I young man begins to go down a hill everything seems to be greased for the occasion. --> Josh Billings
If some of us were not so far ahead, the rest of you would not be so far behind!
KrZ:
You need a manometer. Your fractions sound pretty wide, what sort of packing/how many plates are you using?
DiethylEtherMan:
KrZ: Ahh, the master at wackers...here to help? Thanx. Actually, this time I used only a claisen and stillhead packed with approx 7-8 pieces of broken glass. I have a frac distillation tube, but it takes forever for the shit to get to the top...I think its 300mm.
Anyway, I am going to use that 96g of supposed ketone (wnd fraction) in a al/hg tonight and see how things turn out. I will get back with the results.
In the meantime, do you have any clue as to why I only ended up with this much tone? Would leaving the mixture sitrring overnight affect yields in some way? Or, maybe that overdose of water (if I actually made that mistake)?
Again, I am going to give the DMF wacker another rip at a much smaller scale..during the week sometime. And I will return with the results, making sure to pay a fuckin attention this time.
Peace.
Experience, when labeled a failure, sucks. --> Yours truly.
If some of us were not so far ahead, the rest of you would not be so far behind!
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