Al/Hg background info wanted!

[methlab]

Hi guys! Can anyone explain me what is happening during the Al/Hg Reductive Amination with Nitromethan ? I want to know how the MDP2P is reduced to MDMA, especially when is it reduced and how long does this process take. After amalgamation one starts to drip in the MDP2P/Nitro/MeOH mix over a given time, say 30 minutes. How long does it take to reduce the MDP2P to MDMA. Is it converted immediatly after dropping in the solution or during the rest of the reaction time. I mean, the addition takes e.g. 30min, but the whole reaction takes more than 3 hours. What is going on after the addition. I want to know this for a better understanding of the reaction.
Thanx,

[methlab]

I forgot something: how does the thickness of the Alfoil infect the reaction? I am using a 0.15 foil,
99.8% pure Nitro and the reaction is running very hot. I do only half batches, because i use a 1l 3-neck rbf and a 50cm
condenser. After about 3 hours i have a uniform grey sludge, like MM writes and there is NO alfoil
left. After adding the NaOH the solution turnes dark grey, but not black like some guys told me.
Has the thickness of the foil something to do with the yield? (everthing is added while the rxn is
running full blast).

[runne]

About the dream you are dreaming.. here are my thoughts...

1) There are substantial posts on the subject material you are asking about in TFSearch Engine.
2) It is well advised to have the flask in a water bath to keep temperatures down.
3) The reaction is more controllable if you add most of the Nitro FIRST since this is the most exothermic part of the reaction. Then once you have it added, and the temperature moderated you can then start dripping in your ketone.
4) Thickness of Al Foil.. The thicker the (usually) better. It will slow the reaction down and allow you to add your nitro faster and in a more controlled fashion. In other words, no "volcanos".
5) You may note that in most of the synth's I've seen they do not mention that you need at least a LITTLE H2O in there to start the reaction. If you do not, you will find your flask turns into a VERY thick soap that does not stir well.
6) Regarding Al foil being left in the reaction after 3 hours or so.. I've always had it at least 90% gone, I've sometimes seen some small pieces floating around in there. After the base is added, it is all gone after an hour.
7) Final reaction color after NaOH is added and let to sit for an hour has ranged, for me, from a dark grey, to a dark grey with deep green tones.

Hope that helps.

[Rhodium]

https://www.thevespiary.org/rhodium/Rhodium/chemistry/alhg.osmium.html

[Glasya]

The EtOH I used already contained maybe 5% water. The MeNH2 used was usually 40% aq. soln, so there's more from this source. This is all the water the reaction needs. Don't add extra water like Shulgin. It is not necessary, even when you use higher percentage alcohols, like 99% IPA. H2O is needed in this reaction. Although Al can also dissolve in alcohols, the formation of Al2O3/Al(OH)3 seems to be much more exothermic, which probably (?) helps the reaction (don't ask). An experiment using abs. EtOH and NH3 gas in huge excess yielded absolutely nothing. Too much H2O of course is bad, because imine formation is reversible.

SWIM had read this too, and decided to try it both ways, once SWIM added 50mls of dH2O and the other time didn't add any. SWIM used ACS MeOH and 99.8% MeNO2, yeilds were the same for both reactions, 37.5g MD-P2P w dH2O after re-X 30.7g, and with out dH20 28.9g. SWIM doesn't know where any H2O would have come from in the second run and figured that the keton would have dissolved in the MeOH. Has anyone had a bas experience NOT adding dH2O to this reaction?