Asarone epoxidation by Oxone

[catastrophe]

Thank you both.

[Chromic]

The NMR spectra from the asarone epoxide looks just like the spectra from anethole epoxide (which can be rearranged to anethole ketone by 15% H2SO4). Both samples showed that virtually no alkene remained. Success!!!

Buffered Oxone in methanol can be used to make asarone epoxide. However, H2SO4 rearrangement cannot be used to make asarone ketone.

[uemura]

Beautiful Chromic!!!  
Could you provide us with some experimental details for the succesful synthesis, or references to post/rhods site?

This is the first part. Uemura would now try thermal rearrangement!!! The main physical data on the asarone ketone are in a previous Uemura thread in this forum.

Side Note: The H2O2/MeCN oxidation of 20ml anethole gave 20,4g chewing-gum like smelling epoxide. Destillation for purification will be done tomorrow.

Carpe Diem

[Chromic]

100mmol asarone, 200mL MeOH, 500ml water, 24.4g NaHCO3, 72.7g Oxone. Stirred 5hrs, extracted with DCM. Yielded 89mmol of crude asarone epoxide. A small amount was saved and the NMR spectra came back same as a good sample of anethole epoxide (with the exception of two additional methoxys).

15% H2SO4 rearrangement was attempted and it destroyed the molecule turning it into a crap that did form the bisulfite adduct.

So, we just need to find another way to turn the epoxide to the ketone. The next test will be to verify that anethole epoxide can be turned into anethole ketone. Unfortunately, some glass recently broke and the project will have to wait a bit.

[Chromic]

Btw, in my experience, crude anethole epoxide has been a clear yellow oil (smells nothing like licorice), asarone epoxide has been a light brown very viscous liquid (smells something like asarone, but quite different).

[cilliersb]

Why don't we rearrange the epoxide with Lithium Iodide?

I'm sure this will work!!

[uemura]

Why don't we rearrange the epoxide with Lithium Iodide?
Swim thought that as well, but.... He got not what he expected ......
Added: at least not via the MeCN/MeOH route..

[uemura]

Side note continued, Hopefully Chromic apologizes....
Destillation of the 20.4g crude anethole epoxide   gave 16g water clear heavenly good smelling oily product coming over between 85-90 DegC at 3 Torr (min oil pump pressure) without any signs of thermal re-arrangement.
Yield approx 70% after purification, stuff smells soooo good, can't get out nose.....
BTW: Höring data: anethole epoxide bp = 132Dec at 11 Torr
Uemura's one is lower (even after correction) BUT it smells so good....why going further to the amine?? Put it in your favorite tea!!!

[Chromic]

Yes, anethole epoxide smells much better than the stinky licorice smell of well-purified anethole, I think it smells like rootbeer (not like the sassafras smell of rootbeer, more like the "new" rootbeer found in stores).

Uemura, for a moment there, I thought for a minute you were talking about asarone epoxide... One of us has got to make this route come true. I've got no LiI (tho I do have some impure EtOAc), and although I can see ways to make it (or MgBr2, or LiBr)... I'm really hoping that thermal rearrangement will work for asarone epoxide.