Author Topic: Thermal decomposition of asarone epoxide  (Read 4005 times)

0 Members and 1 Guest are viewing this topic.

Chromic

  • Guest
Thermal decomposition of asarone epoxide
« on: November 24, 2001, 11:46:00 PM »
Standard epoxidation of anethole was used (Oxone in methanol), reaction was conducted at half scale (50mmol). Crude yield of the epoxide was 50mmol. The epoxide was refluxed until the vapours hit 240C (*). Crude yield was 45mmol of PMP2P that tested positive with bisulfite. Maybe some PMMA or PMA will be made...
 
The point is... thermal rearrangement worked for SWIC!!!

Eventually the still will be operational again, and information on the true yield will be passed on. In any case this is confirmation that the ref that Ueruma passed on in Novel Discourse,

Post 237702

(uemura: "Re: Ketones from Propenylbenzenes via the di-bromides", Novel Discourse)
, works!

No more H2SO4 reflux! AWESOME NEWS!

(*) the ketone would have been distilled under reduced pressures after rearranging it via this way, but someone was feeling impatient waiting for a certain replacement piece of glass necessary in the operation of a still to arrive.

Rhodium

  • Guest
Re: Thermal decomposition of asarone epoxide
« Reply #1 on: November 25, 2001, 01:18:00 AM »
Great! Let us know the results after the distillation, and especially the yield of pure isolated "anethone".

Antibody2

  • Guest
Re: Thermal decomposition of asarone epoxide
« Reply #2 on: November 25, 2001, 01:25:00 AM »
cool! how long was it in reflux or how long to reach 240C? was there much noticable polymerization.

"All those memories lost like rain..."

Chromic

  • Guest
Re: Thermal decomposition of asarone epoxide
« Reply #3 on: November 25, 2001, 03:48:00 AM »
SWIC no longer has plans to distill the anethole ketone (I couldn't resist plugging it into a MM synth, it looks like relatively clean ketone), but NMR will be run on some of the saved oil to get an idea of its purity and confirm identity (not that its identity is in ANY question).

The epoxide was a light yellow oil, it was placed into a small flask fitted with a thermometer, stir bar, and an air condenser... rested on a hotplate (no bath) and heated until the vapours hit well above 210C. It turned out a light brown oil, not viscous at all (no tar), smelling like previously made PMP2P and passing the bisulfite test.

This method is so easy. Screw H2SO4 hydrolysis, this is much easier and gives at least as good results.

The biggest question on my mind is if SWIC did really make asarone epoxide, will this method work... and since I know beta-asarone can be distilled with no vacuum at 300C, my answer has to be yes, yes it can...

Chromic

  • Guest
Re: Thermal decomposition of asarone epoxide
« Reply #4 on: November 25, 2001, 08:20:00 AM »
PMMA.HCl was successfully made. Low yields (2.1g from 6g undistilled ketone) were obtained, but I don't think that things could have been done any faster... (ran a micro-version of a MM Hg/Al in 3-4hrs total time)

Onto TMA-2 via buffered Oxone!  8)

Chromic

  • Guest
Re: Thermal decomposition of asarone epoxide
« Reply #5 on: November 25, 2001, 07:38:00 PM »
My challenge to MDMA-inspired bees:

Who is going to be the first to run a fully buffered performic (pH>6.6) to produce isosafrole epoxide (instead of isosafrole glycol or isosafrole formyl glycol) and rearrange using this super-simple super-easy super-timesaving technique? (this means using around 600-700g of NaHCO3 instead of 71g NaHCO3, and venturing into uncharted terroritories with the performic acid method... heh)

And, who's going to be first to use a fully buffered peracetic approach using this technique? Semtex's writeup has always needed a shot in the arm, this could be a big boost for it.

Rhodium

  • Guest
Re: Thermal decomposition of asarone epoxide
« Reply #6 on: November 25, 2001, 09:40:00 PM »
Fully buffered, as in that all the produced formic acid is turned into sodium formate? Could work, and seems interesting.

I just would like to know the exact yield of this thermal rearrangement (I am also eagerly awaiting your distillation equipment piece  :)  ).

Vibrating_Lights

  • Guest
Re: Thermal decomposition of asarone epoxide
« Reply #7 on: November 25, 2001, 10:42:00 PM »
Chromic is the shit :)

Chromic

  • Guest
Re: Thermal decomposition of asarone epoxide
« Reply #8 on: November 25, 2001, 11:07:00 PM »
The ref say that the yields are 80% for both anethole and isosafrole epoxides. I'd tend to agree as I got similar performance of the ketone as I have from H2SO4 produced ketone (except that it looked much cleaner and I seemed to have gotten a higher yields after thermal rearrangement than after 15% H2SO4).

twodogs

  • Guest
Re: Thermal decomposition of asarone epoxide
« Reply #9 on: November 26, 2001, 10:18:00 AM »
Chromic, the isosafrole glycol also thermally rearranges to the ketone as discussed in

Post 219402 (missing)

(twodogs: "Re: LiI catalyzed pinacol rearrangement possible?", Chemistry Discourse)
.

uemura

  • Guest
Re: Thermal decomposition of asarone epoxide
« Reply #10 on: November 26, 2001, 01:56:00 PM »
Chromic, very cool.....
You've been faster than Uemura!  ;)  Uemura spent the weekend in his lab and didn't check the posts. He likes your confirmation of thermal rearrangement procedure. Now he will run in parallel with you his own tests. Of course he will post his results as well.
Carpe Diem

uemura

  • Guest
Re: Thermal decomposition of asarone epoxide
« Reply #11 on: November 26, 2001, 03:23:00 PM »
A bit nit-picking from Uemura  :)  At least he has to report a minor detail from last weekend's lab work.

The epoxide was a light yellow oil, ...
The crude antheole epoxide (from MeCN/MeOH/H2O2) is a clear yellow oil. Slowly vacuum destillation give however first the water clear epoxide (in 75% yield after destillation) within a 5 degree destillation range. In the flask a deeper yellow viscous oil with a definitly higher bp remains (11% based on anethole).

More details to come...

Chromic

  • Guest
Re: Thermal decomposition of asarone epoxide
« Reply #12 on: November 26, 2001, 06:53:00 PM »
I never distilled the epoxide... so I have no results to say what the yields of this procedure are, just that it does works as stated. But it looks like Twodogs has written that not only epoxides, but glycols can be rearranged. I can't believe I never read this before!

uemura

  • Guest
Re: Thermal decomposition of asarone epoxide
« Reply #13 on: November 27, 2001, 08:03:00 PM »
Chromic,
Have a look in the new thread of Uemura in the Novel Discourse.
Suppose the Uemura MeCN/MeOH/H2O2 epoxidation works as your oxone epoxidation, then in the case of anethole you could go ahead without purification. In case of asarone however, Uemura could get only 40% of purfied asarone epoxide.
Carpe Diem