turd
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Al/Hg under mild conditions
Two notes:
1) Posting in beginnings since what follows is very unscientific.
2) I've not been following clandestine chemistry closely, maybe this is all well known.
Searching for a mild reduction method that does not deiodinate aromatics (see discussion in https://www.sciencemadness.org/whisper/viewthread.php?tid=23...) I found a reference where a nitroethane was reduced to the hydroxylamine with
Al/Hg in neutral THF at 0°C (J. Chem. Soc. Perkin Tans. 1, 2000, 3487-3494). The same authors described the same reaction
ten years earlier, albeit with worse yields. They also describe the sensitivity of the hydroxylamine to oxidation, so it does seem to be legit.
That caught my attention for two reasons: As far as I know the pharmacological relationship of phenethylamines and their corresponding hydroxylamines
is not yet completely established (one is a prodrug of the other?). On the other hand, AFAIK Al/Hg reductions of nitrostyrenes are typically performed
under strongly acidic conditions (see https://www.erowid.org/archive/rhodium/chemistry/nitrostyren...).
Since there still was 4g of a botched NaBH4 reduction of 2,5-dimethoxy-beta-nitrostyrene (25DMBNS) in the fridge a quick experiment was performed. The
substrate was an orange oil with melting point below RT. In retrospect it probably was a mix of the nitroethene and the nitroethane.
The thing was dissolved in ~150 ml THF with 20 ml water. Meanwhile 14 g Al foil was activated for 20 min with an aqueous solution of HgCl2. The
activated Al foil was then added via a powder funnel to the THF solution cooled in an ice bath. After addition of two thirds of the Al foil, the flask
was completely full and stirring with a magnetic stir bar impossible. LOL. So instead the flask was shaken for a few minutes. Then stirring was
somewhat possible, but the ice had molten. 
After 10 more minutes of stirring, the whole thing was vacuum filtrated through standard filter paper, which surprisingly posed no problem at all.
There was much unreacted Al/Hg, which when sucked dry heated up considerably. The filter cake was washed with some IPA and together with the unused
Al/Hg deactivated using aq. NaOH.
Surprisingly the filtrate was less colored than the original reaction mixture (interpretation: there was still nitrostyrene which was reduced). It was
reduced under vacuum until two phases appeared and the heavy organic phase extracted with DCM. The DCM was dried over NaSO4, removed under vacuum. The
resulting oil was dissolved in IPA giving a strongly alkaline solution to litmus. Ca. three Pasteur pipettes of conc. HCl were needed to neutralize
the solution. Acetone was added, which yielded no precipitation. After one day at -18°C still no precipitation. The flask was shaken, kept at -18°C
for two further days, when appreciable amounts of crystalline material formed. Result of analysis: 2,5-dimethoxy-phenethylammonium chloride
(2C-H.HCl).
My conclusions:
- Al/Hg is a powerful reductor even without acid or elevated temperatures. Maybe the harsh reaction conditions are only used to compensate for
inadequate stirring? Some experimentation is certainly in order.
- To selectively obtain the hydroxylamine, strict temperature control will have to be used.
Sorry if all of this was trivial and known to everybody but me, but I was quite surprised to see the Al/Hg work under such mild conditions. 
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kmno4
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I performed very similar reaction (seen somewhere on OrgSynth )
but with acetophenone oxime in dioxane (+water).
Very exothermic reaction and
...the flask was completely full and stirring with a magnetic stir bar impossible...
I did not know what to do, but I had a vision and added some solid NaOH.
A miricle has happened: all gray pulp collapsed to very small volume of water-based cake. Remaining dioxane was just pipeted out and evaporated.
Слава Україні !
Героям слава !
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turd
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My reaction was not very exothermic ("measured" by touching flask...). It melted the ice bath, but never went above RT.
Do you have a pointer to the OrgSyn preparation? For alpha-phenethylamine I only found a Ra/Ni and a Leuckart reaction. I'm interested in the
preparation of Al/Hg and OrgSyn is often nicely explicit as opposed to other scientific literature (often they don't even mention if they use powder,
foil or granules and I thought reproducibility was a key aspect of scientificity!). I'm pondering trying granules - that should make it much slower
but on the other hand much easier to stir. I wish I had an mechanic stirrer. 
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