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MDMA via Tosyl Chloride Intermediate?

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Ollie-RSM:
Has anyone ever heard of MDMA being produced by a Markonikov hydration of safrole and conversion of the alcohol to an alkyl tosylsulfonate (via rx with tosyl chloride) followed by Sn2 amination with methylamine?This synthetic pathway would be very similar to the bromination/debromination pathway that is recently in vogue, and might be even simpler. Plus tosyl chloride is dirt cheap ($23 for 1kg).I'm away from school for the summer so I don't have access to CAS, hence no citations. Just throwing the idea out.ORSM

Tr-E-frog:
ORSM,Funny you should mention this...I've been wondering a about it for a little while. I can't say that I've seen any discussion on the bulletin board, but hopefully we can get one going. Drone, Rhodium, anybody out there thought about this???  Is the methylenedioxy ring going to be stable under such circumstances or is this idea dead in the water?Many thanx,treefrog.

Siegfried:
Hi ,
I try this procedure alot and it was much better than normal alkyl-halide process because the tosylate ( and brosylate or nosylate ) don't give a lot of elimnation contrary to the alkyl-halide .
I got the alkohol intermediate with oxymercuration of the allylbenzene and made the tosyaltion with tosylchloride/pyridine , then the SN2 in MeOH with a little THF ofr solubility purpose and RT . the yield and reaction time are :
>95%,20min,RT for oxymercuration
>95%,45min,RT for tosylation
50-60%,5d,RT for SN2 with MeNH2-MeOH
The RT and polar solvent are very miportant because increase the temperatur favorise the elimination , decrease the polarity too .
Anyway , this family of SN2 is favorised with polar protic solvent as MeOH ( see the March ) .
As i wrote under another topic , the tosylate are very good but there is even better leaving group they don't give any elimination and have better cinetic : the Triflate , but it's an expensive reagent .

Ollie-RSM:
Siegfried, it's good to hear of your success! Did you add any base during tosylation to suck up the HCl produced? Just curious.Also, is mercuric acetate available anywhere but chemical houses? Could you make it by combining HgCl and sodium acetate, perhaps? Personally, I would be tempted to use acid-catylized hydrolysis and just distill the alcohol off of from any side products...although I'm not sure how well this would work.ORSM 

Siegfried:
For the tosylation of alkohol , the base is pyridine , because :
1) it take the HCl
2) very important : it form a complex with tosyl chloride which make the attack by the alkohol on the sulfur more easily .
For the hydratation of the alkene , acid medium is not good because the 1-aryl-2 propanol first formed is rapidly deshydrated to the stabilized isosafrole wich is hydrated to the 1-aryl-1-propanol the result is :
1) very poor yield in 1-aryl-2-propanol
2) mixture of 1-aryl-2-propanol and 1-aryl-2- propanol which are not easy to separate ( must use distillation ) .
The oxymercuration process give only the 1-aryl -2-propanol intermediate without rearrangement in about 20min with >95% yield but HgCl2 can not be used ... Sorry 
HgAc2 or Hg(NO3)2 or Hg(ClO4)2 or Hg(CF3COO)2 can be used .
You must use Hg2+ mercuric and not Hg+ ion ( mercurous ) .
You can make HgAc2 from HgCl2+CH3COOH but you must purify it .
Anyway HgAc2 can easily be purchased .
I will probably send the total procedure in HTML format with all the detail and mechanism to Rhodium's site soon .

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