Author Topic: Thermal isosafrole epoxide rearrangement trials  (Read 14510 times)

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Vibrating_Lights

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Thermal isosafrole epoxide rearrangement trials
« on: February 02, 2002, 07:54:00 PM »
Various trials of rearrangement of isosafrole epoxide have transpired.  Here's what they got.  with 89gms of undistilled isosafrole epoxide.  distilled at atmospheric pressure yeiled 15gms of pure Mdp2p and a flask full of polymerized crud.  when 89 grams of the same crude epoxide is vac distilled there is yeilded 70 gms of isosafrole epoxide apoun further distillation at atmospheric pressure there is yeilded 62gms of MdP2P which was collected visualy with UV light collecting the fraction that glowed yellow. Bisulfite verufication +
Amination pending
VL_
Decimal_

Rhodium

  • Guest
Re: Thermal isosafrole epoxide rearrangement trials
« Reply #1 on: February 02, 2002, 08:05:00 PM »
Very good. What whas the method used for the epoxidation, and what was the yield? Distillation temperature and vacuum used?

And don't forget to report back after your amination.

LaBTop

  • Guest
Re: Thermal isosafrole epoxide rearrangement trials
« Reply #2 on: February 03, 2002, 01:54:00 PM »
If your amination (mention which method pls) turns out ok, then
""which was collected visualy with UV light collecting the fraction that glowed yellow""
is something very handy and new in the arsenal of the underground cook. LT/

PS: what colour did the other fractions (before ketone and after) turned up????? And is there a sudden change in colour or a slowly fading into another shade when fractions change in temp?

WISDOMwillWIN

Flip

  • Guest
Re: Thermal isosafrole epoxide rearrangement trials
« Reply #3 on: February 03, 2002, 07:02:00 PM »
Thermometer was broken.  that is why the UV was used.   swim will dream both again when new one arrives to copnfirm results.  there is a few drops of forrun that has a light white glow.  only a few drops. Similar to the glow of isosafrole. then the yellow can be seen in stillhead as it begins to come over  there is a few minutes from the last drop of the white before the yellow makes it into the condensor.  vaccume was 30.2" 167 gms of previously distilled isosafrole tested with nano pseudonitrosite. epoxidised with 1.5lbs of oxone in a 5 gallon bucket.
VL_

PoohBear4Ever

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Re: Thermal isosafrole epoxide rearrangement trials
« Reply #4 on: February 03, 2002, 07:42:00 PM »

epoxidised with 1.5lbs of oxone in a 5 gallon bucket.




What did you use to stir this concoction, and at what speed (1800?)?  Will a decent magnetic stirrer suffice?

PB


noj

  • Guest
Re: Thermal isosafrole epoxide rearrangement trials
« Reply #5 on: February 03, 2002, 08:13:00 PM »
for swim, it was 450g isosafrole, 2L MeOH, 2Gal dH2O, 1lb Oxone, yield was about 350g epoxide.



If you prepare your oxone/MeOH/H2O prior to using, you can filter the precipitate, which is potassium sulfate. Oxone level is not affected by this. This will allow unhindered magnetic stirring other than water resistance.



Real men cook naked.

Flip

  • Guest
Re: Thermal isosafrole epoxide rearrangement trials
« Reply #6 on: February 03, 2002, 09:39:00 PM »
Hell yeah thanks.  Swim used more oxone because it is 85%.
VL_

Vibrating_Lights

  • Guest
Re: Thermal isosafrole epoxide rearrangement trials
« Reply #7 on: February 03, 2002, 09:54:00 PM »
Noj, how much extraction solvent did you use for the 400+ grams.
VL_

noj

  • Guest
Re: Thermal isosafrole epoxide rearrangement trials
« Reply #8 on: February 03, 2002, 11:59:00 PM »
I honestly don't recall the amount of DCM, but it was likely 3x100mL. When there are no solids in the solution, it is easy to extract. Just let it settle awhile in the sep funnel, tap off the epoxide, and extract the water with DCM.
Stirring was done on a Corning 320 with a 3" bar. Every thing else was like Chromic wrote.

Note that weight was the epoxide. I'll do a rearrangement and bisulfite test in a couple days.

What is the smoke temperature of DOT4 brake fluid?

Real men cook naked.

uemura

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Re: Thermal isosafrole epoxide rearrangement trials
« Reply #9 on: February 04, 2002, 04:47:00 AM »
From the Höring paper: Ber. 1905, 38, page 2297

Isosafrol-epoxide bp: 140-142degC at 9mm
Isosafrol-ketone  bp: 283-284DegC at normal pressure

Yield of ketone by Höring: 80% using destilled epoxide. Water clear oil, almost without smell (the epoxide does smell nice).

sunlight

  • Guest
Re: Thermal isosafrole epoxide rearrangement trial
« Reply #10 on: February 04, 2002, 06:26:00 AM »
Isosafrol-epoxide bp: 140-142degC at 9mm (thanks uemura)
MDP2P 140-145 (9 torr)  (thanks Osmium)

It seems difficult to isolate the ketone from the epoxide, right ?

Wich is the color of ketone ? Pale yellow or consitent yellow ?

Very interesing research, thanks.

I'm interested in your UV method. What kind of UV did you use ? The bactericide one hurts your eyes...

Osmium

  • Guest
Re: Thermal isosafrole epoxide rearrangement trial
« Reply #11 on: February 04, 2002, 07:17:00 AM »
If I ever tried to isomerize the epoxide I'd probably first distill it with an oil pump (low boiling point) to purify, and then do the actual isomerisation in a flask (with an air condenser) under vacuum to limit the (reflux) temperature. I have seen this method being used for the thermal claisen rearrangement of phenolic allylethers, and yields were higher due to less thermal stress. It will take some time though, but better to heat for an hour at 200 or so than 280°C for only a few minutes. This might limit side reactions, I'm pretty sure it is worth a try.

I'm not fat just horizontally disproportionate.

Rhodium

  • Guest
Re: Thermal isosafrole epoxide rearrangement trial
« Reply #12 on: February 04, 2002, 07:30:00 AM »
But what about catalysts... Why is noone interested in sprinkling lithium salts or other weak lewis acids on their epoxide?

Osmium

  • Guest
Re: Thermal isosafrole epoxide rearrangement trial
« Reply #13 on: February 04, 2002, 07:49:00 AM »
Another hard to aquire chem, anhydrous conditions, difficult to get (for some) ethyl acetate.

But the yields of course are clearly in favor of using Li salts.

I'm not fat just horizontally disproportionate.

Rhodium

  • Guest
Re: Thermal isosafrole epoxide rearrangement trial
« Reply #14 on: February 04, 2002, 08:05:00 AM »
I did not mean for general use for everybody, but we are now investigating a whole new area of chemical transformations, so it must at least be tried ONCE.

Osmium

  • Guest
Re: Thermal isosafrole epoxide rearrangement trial
« Reply #15 on: February 04, 2002, 09:00:00 AM »
It's ok boss, nobody stops YOU from trying.  ;)

I'm not fat just horizontally disproportionate.

Vibrating_Lights

  • Guest
Re: Thermal isosafrole epoxide rearrangement trials
« Reply #16 on: February 04, 2002, 09:03:00 AM »
<3x 100ml> arent those the ammounts for a 16 gm extraction.  Swim cannot see 300 ml of dcm holding that much oil. more like 3x 1000 ml dcm. swim used 3x1000 for 167 ond only isolated 86gms. No solids present after quick filtering through scotch brite pads.  Can the Dcm Ammounts really be reduced that far.

Rhodium

  • Guest
Re: Thermal isosafrole epoxide rearrangement trial
« Reply #17 on: February 04, 2002, 10:06:00 AM »
*Sigh*

I get a terribly stressful feeling when I see all the unexplored promising routes and compounds just lying there in my piles of paper, and on this site. Often 90% of the work is done already, a procedure must just be tested with an analog, or with different reaction times, temperatures and/or solvents to optimize the yield and assure purity.

The progress here at the Hive is painfully slow sometimes, people have been discussing the peracetic acid oxidation and LiI epoxide rearrangements for five years, and finally Semtexium did the peracetic last year with excellent results, just as expected. The LiI experiment will probably work just as good. But someone must do it! Even if I worked full time in a well-funded lab, only testing novel procedures, I would never have the time to keep up with the new suggestions to do things, and to optimize the results of a particular reaction to all the interesting precursors we want. If someone wants to make methamphetamine from P2P, they won't just use the appropriate procedure for MDMA and just substitute the MDP2P for P2P - and being the perfectionist I am, I feel it must be tried in practice for us to determine the yield for the particular compound, not just that this-and-that reaction usually gives 60-80% yield with nitroalkenes, I demand to know the exact yields for our five most often used nitroalkenes, as well as footnotes for the compounds when necessary. For example, in my Pseudonitrosite FAQ, there is one general procedure, a table of yields and physical properties, and finally a footnote talking about the neccessary special handling of the asarone derivate. Of course everything should be referenced, and the references checked for pointers to other articles that might help to perfect the reaction.

As I'm the librarian collecting all the good work of the people here and suggesting the most promising avenues to pursue in the future, and I spend my own spare time doing all that reference research, I'm not capable of doing all the labwork myself too. If I would personally try all the reaction varations of our new ideas instead of the theoretical research, then there would a big reduction in novel stuff found for everybody to enjoy. And if I would divide my time between the two, there wouldn't be especially much produced out of any department, as each would only get my attention during half my spare time, and even if I concentrate on only the theoretical side, I still have too little time to produce as much as I want.

Just look at my declining performance at my site (Over 100 new additions in October, 75 in November, 30 in december, and now in January only 11, of which five is just PDF/ZIP files, nothing I have written myself and put any work into!!). And I have not made any practical contributions either, other than taking pictures of ammonium nitrate crystals. If it continues like this, people will be bored with my site as not much new is happening, methods becomes obsolete as I haven't updated the documents with the latest breakthroughs, and I no longer have a purpose here...

I want help with practical tests and theoretical research, I have no possibility to verify everything interesing that is found here, neither practically or theoretically, and just abandon good ideas like we do now is terrible intellectual waste...

noj

  • Guest
Re: Thermal isosafrole epoxide rearrangement trials
« Reply #18 on: February 04, 2002, 10:17:00 AM »
VL, if you tap off the bottom oil first, that will account for the majority of the epoxide ~80%. The DCM is to get the rest that may be suspended in solution. The final 100mL DCM is quite clear so it may not even be needed.

Real men cook naked.

noj

  • Guest
Re: Thermal isosafrole epoxide rearrangement trial
« Reply #19 on: February 04, 2002, 10:23:00 AM »
Rhodium, in the few years that I have known of your site, I have never become bored with it. It has so much information that I could never absorb it all. But I visit daily and find new things each time. So kudos to you and your efforts!

Real men cook naked.