Reduced boro yields 94.6%--Awesome!

[Argox]

You may be right, boss, but boro is cheap compared to PMK. I'll just remember next time to have enough. Experimentation is fine, but sometimes practical considerations take upper hand.  I'll keep trying, though, with remnant to crystallize it.  Mdma seems to be a tough molecule and can stand a lot of abuse.

Question:  Some NaOH (along with traces of NaCl) is present during distillation of mdma.  Would this affect the product, much in same way safrole is isomerized with KOH?
In the port of Amsterdam, there's a sailor who sings
Of the dreams that he brings...

[Rhodium]

I would perform an acid/base extraction before the distillation any day of the week to avoid any problems, which are indeed possible. You would not get any "isomerized" MDMA though - just a loss of yield by formation of the infamous "red tar" in the distillation flask.

[hmx777]

SWIM has attempted a couple of times to reduce ketone with ammonium acetate to the product.  It seems the NaBH4 is too reactive and reduces the ketone to the alcohol.  Very poor desired product yields were seen (< 10%).  SWIM has tried making conditions absolutely favorable (silica gel, proper pH adjustment, etc....).  As far as I can see there is nothing different from your procedure and SWIM's except for the Methylamine.  Is there something SWIM is missing?  Does this method actually work well?  If so, why all the fuss on using cyanoboro(which, BTW, works very well)?

[terbium]

SWIM has attempted a couple of times to reduce ketone with ammonium acetate to the product.  It seems the NaBH4 is too reactive and reduces the ketone to the alcohol.  Very poor desired product yields were seen (< 10%).
Ammonia is not methylamine! The N-methylimine from methylamine is much more stable than the imine from ammonia. When using methylamine, all of the ketone gets converted to methylimine before the borohydride is added and so the borohydride reduces the methylimine to the N-methylisopropylamine. When using ammonia, the reaction equlibrium does not favour the imine formation so there is a lot of unconverted ketone when the borohydride is added and the borohydride reduces this to alcohol.

SWIM has tried making conditions absolutely favorable (silica gel, proper pH adjustment, etc....).  As far as I can see there is nothing different from your procedure and SWIM's except for the Methylamine.
Yes, that is the difference. The difference between methylamine and ammonia.

Is there something SWIM is missing?
Yes, that there is a big difference between using methylamine and using ammonia.


Does this method actually work well?
Yes, it does work well, very well. It works very well when using methylamine. It hardly works at all when using ammonia.


If so, why all the fuss on using cyanoboro(which, BTW, works very well)?
Because cyanoborohydride will work with ammonia to produce the amphetamine.

[Argox]

terbium 100 percent
In the port of Amsterdam, there's a sailor who sings
Of the dreams that he brings...

[otto]

hi hmx777,

otto had the same problem, when he tried it. so he can confirm everything you said. ketone, NH4OAc, SiO2, MgSO4 in MeOH, stirred and then NaBH4. yield: 20% amine and 70% alcohol.
unfortunately, no cyano is around, so otto has to mess w/ other things.

otto

[hmx777]

Thanks for clarifying that.  I thought as much.  However, SWIM has another idea, let me run this by you guys.  What about attempting to reflux the ketone and ammonium acetate in a Dean Stark water trap?  Would it be possible to first generate enough imine, then add the NaBH4 after a optimal yield of imine was formed.  SWIM doesnt think of isolating the unstable imine, but merely start adding NaBH4 slowly once the equilibrium of imine<>ketone has formed.  Perhaps using molecular sieves,etc... would be another way?  Maybe another would be to add absolute ethanol to grab the water away forming an azeotrope and distilling it off? But, I think the elavated temperature and water trap might work better?

[Rhodium]

Your dean-stark idea should work fine (or at least better than other methods).

[UKBEE]

would it possible to create methylamine in situ from the reduction of nitromethane, or would that produce shit loads of water and fuck up the reaction.

Maybe i'm talking outta my ass.
I love the smell of Ketone in the morning.

[Chromic]

Rhodium, for this idea to work, wouldn't you then have to remove the solvent you used to remove the water (ie chloroform, toluene, perc, etc) before proceeding to the reduction? I thought the borohydride reduction was commonly done in methanol, not in a non-polar..

[UKBEE]

Can anyone tell me if reducing nitromethane in situ would be viable for the NaBh4/Methylamine/MDP2P Reduction ?


I love the smell of Ketone in the morning.

[Rhodium]

Chromic: Yes, if the imine was formed in toluene, you distill off most of it and then dilute the residue with a suitable amount of methanol to make a toluene-containing methanolic solution of the imine. Toluene and methanol are miscible as far as I know. I think methanol must be used as solvent, as NaBH4 is not soluble in toluene.

[UKBEE]

Subject: Distilling toluene

Yes, if the imine was formed in toluene, you distill off most of it and then dilute the residue with a suitable amount of methanol to make a toluene-containing methanolic solution of the imine. Toluene and methanol are miscible as far as I know. I think methanol must be used as solvent, as NaBH4 is not soluble in toluene.

was that directed at my question ?

So SWIM couldn't do it all one pot like the MM Al/hg reduction ?

whats the ratio of NaBh4 to Nitro to reduce it all to methylamine.

Could it be the nitro ---> methylamine de carried out in acidic conditions to generate methylamine.HCL ? (for storage)

Cheers

I love the smell of Ketone in the morning.

[UKBEE]

ok point taken madmax. so whats method of the MM Al/Hg that produces the Methylamine thats from the nitro isn't it ?
I love the smell of Ketone in the morning.