MDA via murcuric nitrate & acetonitrile

[El_Zorro]

Has anyone tried this synth from TSII?  Strike said that it didn't work, but only because anhydrous Hg(NO₃)₂ was needed, and nobody had a way to produce that.  Couldn't you just dissolve the Hg(NO₃)₂ in some solvent, and then add some Na₂SO₄ or MgSO₄, then distill off the solvent under inert atmosphere?  Or just run the reaction in the now dry solvent?  And how can the Hg(NO₃)₂ be made from elemental Hg?  Just react with HNO₃?  Or would that not give the properly oxidized nitrate?

The reason I'm asking is that the reported yeilds are 80% MDA from safrole, which is a hell of a lot better than any other reactions I see here.


Who is that masked man?

[Aurelius]

and the reactants/products contain stuff that isn't healthy for you or the environment.

[PrimoPyro]

Solvents are horrible for the environment, too. So that makes all syntheses bad for the planet. Better stop then.  

So what do you not do? You dont put your solvents down the drain, right? So dont put your mercury down the drain either. Problem solved.

Oh, and the most commonly used method for MDMA involves mercuric chloride. So this isnt exactly something new and horrible.  

PrimoPyro
Will perform sexual favors for females in exchange for 1,2-dimethylaziridine. PM for details.

[Rhodium]

This synthesis uses a stoichiometric amount of mercuric nitrate (with a molecular weight of ~350 g/mol), which is 500 times more than you would ever need to spend to produce the same weight of MDMA hydrochloride using the Al/Hg reductive amination.

[terbium]

Oh, and the most commonly used method for MDMA involves mercuric chloride. So this isnt exactly something new and horrible.
Not to necessarily say that I concur with Aurelius, but your comparison is invalid since only small ammounts of mercury are required for the Al/Hg reduction used in the preparation of MDMA while the current topic of discussion requires stoichiometric quantities of mercury.

Oh, and I think that Rhodium too has taken the same position as Aurelius wrt reactions that require stoiciometric amounts of mercury.

Edit:
Whoops, seems I somewhow didn't see the post by Rhodium just before this.

[PrimoPyro]

Why have it on your website and in TS2 if no one can use it?
Will perform sexual favors for females in exchange for 1,2-dimethylaziridine. PM for details.

[Rhodium]

To publish it in Total Synthesis was a mistake by Strike, I think. The reason I have it on my page is just because it is yet another method to aminate an alkene, and therefore I want it there. It is not a suggested method at all.

[El_Zorro]

Yeah, it does use a lot of mercury.  But still, the Al/Hg reaction uses murcury salts as well, and it takes a very small amount of mercury to contaminate a very large amount of land/water.  At the end of the reaction, metallic mercury is produced, which would most likely be the starting material used to get mercuric nitrate.  So what's stoppong someone from recycling that?  I'd doubt almost any of the bees who perform Al/Hg rection recycle their Hg.  I'd bet they pour the post reaction waste into milk jugs and set it outside of their local college chemistry department with a note, that is if they aren't just dumping it in their backyards.  The Al/Hg reaction has become almost the HI/RP reaction for X cooks.  I think that a competant chemist should be able to do this synth without ruining his/her environment.  Whether or not I would be that capable of a chemist, we'll never know, because I personally don't trust myself to perform reactions using Hg salts, I just don't trust myself enough.  But I do have academic interest in this particular reaction, though.
Who is that masked man?

[PrimoPyro]

I seriously used to place very high interest on this method, but when you look at the numbers, it quickly becomes a serious deterrant.

Aside from the environmental concerns, the sheer quantity of needed mercuric salt makes it a very expnsive venture. As for making your own Hg salts, that's fine, but not when the amount of work involved to make anhydrous Hg(NO3)2 far exceeds the logical threshold of acceptable work effort for this compound.

Making anhydrous Hg nitrate is not easily feasable in any method that allow for production of a truly usable quantity. And buying it becomes VERY expensive when it is not renewable, and you need lots of it because it is so heavy.

Seriously, when you need 32.46g of Hg(NO3)2 for just a little 100mmol reaction, it doesn't seem to scalable. That's only ~16.3g of safrole. You need twice as much mercury nitrate as you do safrole, that is ridiculous. See what I mean?

Sucks doesnt it? I liked this idea too. For a long time I was really interested in adding N-methylformamide to safrole, because it would make the N-formyl-MDMA, and when you reduce the organo-mercury nitrate with NaOH/NaBH4/H2O, the formyl group would hydrolyze off as well, making MDMA in one reaction, providing that NMF adds of course. I still love the idea, but fuck man, when you need 100g mercury nitrate for only 50g safrole, and the nitrate isn't even reusable, it really doesn't seem worth it. It's like spending extra money so you can have extra headache.

PrimoPyro
Will perform sexual favors for females in exchange for 1,2-dimethylaziridine. PM for details.

[El_Zorro]

Yeah, I see your point, it does use a shitload of mercury.  But let's think about it.

All the reaction is is just dumping the anhydrous salt and acetonitrile in a pot and adding safrole, then working up.  Can this reaction not be done in a solvent?  Could you not just make Hg(NO₃)₂*H₂0 yourself from metallic mercury, dissolve it in a solvent, and then add a drying agent to get rid of the water, filter, run the reaction, then collect your metallic mercury and run it again?  What solvents would be appropriate?
Who is that masked man?

[PrimoPyro]

I think straight chain alkanes would be the best solvent for this, as they would be completely unreactive toward the reactants.

I'd just use acetonitrile as the solvent, personally.
Will perform sexual favors for females in exchange for 1,2-dimethylaziridine. PM for details.

[El_Zorro]

what is the solubility of Hg(NO₃)₂ in acetonitrile?
Who is that masked man?

[Aurelius]

For PrimoPyro and Terbium, aurelius is definitely against the use of stoichiometric amounts of mercury compounds.  However, aurelius realizes that amongst the bees here, only a lucky few have the resources to use chems other than those which might be harmful to the environment.  (or facilities for proper disposal/reuse)  aurelius isn't up for wholesale discouragement in the use of mercury, just BE CAREFUL for your sake and the environments.

[PrimoPyro]

I think terbium was against the use of lots of mercury as well, not for it or indifferent, but I could be wrong.

I am not agreeing with using copious amounts for mass production purposes, more of just for academic experimental purposes. In the name of science, ya know.  

PrimoPyro
Will perform sexual favors for females in exchange for 1,2-dimethylaziridine. PM for details.

[El_Zorro]

Well, this synth seems a little different than most, since the mercury is reduced to metallic mercury at the end of the reaction and drops to the bottom of the flask as a free liquid.  Can anybody say, recycle?  The reaction mix can just be decanted off, and maybe a little left, and it and the mercury extracted with a nonpolar less dense than water, just to get all of the product, and then pour the mercury into a container, to be converted back to Hg(NO₃)₂ at a later time.  Any remaining liquids can be amalgumized and evaporated to get the mercury wastes down to an absolute minimum volume.
Who is that masked man?

[Osmium]

That's right, but I doubt many of our members know how to safely convert the Hg back into the nitrate without poisoning themselves and their surroundings.

This reaction does sound interesting for high potency drugs like the DOX family, where 1g of Hg compound will produce several hundred single doses. MDA etc. are too bulky since they will yield only a few doses per gram Hg. Too much waste being produced.
I'm not fat just horizontally disproportionate.

[El_Zorro]

yeah, but I especially like the recylability of this reaction scheme.
Who is that masked man?

[Rhodium]

Even with careful recycling, where you are able to recover 99.5% of the Hg, you are still dispersing 1.5g of mercury into the environment for every molar batch of product. And who knows how much of that would end up in your product anyway, as this reaction involves a organomercury intermediate (unlike the Al/Hg reduction, where the Hg stays inorganic the whole time).

[El_Zorro]

Can this problem be solved by an excess of borhydride?

And as for the aqueous waste, what would be the best way to amalgumate any residual Hg compounds?
Who is that masked man?

[moo]

At worst, they can be a fucking nightmare.

http://www.udel.edu/OHS/dartmouth/drtmtharticle.html