Al/Hg reduction

icecool · Insistent Chemist

How much Al should you use SWIM uses 2 times as much grams Al as the substrate.
So for 5g P2NP he uses 10g Al and for 5g 2,5-dimethoxynitrostyrene he uses 10g Al.
Anyway now SWIM used a head stirrer and it worked like a charm really perfect.
He cut strips of 4 times folded Al foil (finally 0,3mm thick), and it then was cut in 5x1cm strips and folded around a pencil.
Most part of the rings where destroyed by the overhead stirrer but that didn't matter, he added quite often new HgCl2 first 40mg then another 40mg 20 minutes later then 20 minutes later 45mg then another bit no mg known since it was just a bit tossed into the flask which caused a really heavy reaction (after all it probably would have been 80mg in there at once) so it almost spitted out some stuff out of the condenser, luckely it didn't....
Next time SWIM won't just throw some more in but really weigh it.
For the further rest almost all the Al dissolved and when the heavy reaction occured only little pieces that were still left in there started to react heavily and started foaming etc, but because of the strong stirring it still did it's work for maybe 40-50% and the other stuff like 18g or so reacted perfect the 2g might have got lost in the heavy foaming part like I sayd.
SWIM will let it stirr until tomorrow then distill off the EtOH and IPA (the nitrostyrene was dissolved in 100ml GAA and some IPA like 100ml or so).
He reduced 2,5-dimethoxynitrostyrene though 10g with 20g Al foil in EtOH.

And Al methoxide and ethoxide where is talked about in some posts above this one, will that form when doing an Al/Hg reaction on MeOH?
And what solvent is used there then, and when using MeOH or EtOH when doing reductions on P2NP won't there also form Al methoxide then?

Radiumhero · Fri Sep 16, 2005 10:59 am

Swirh did following , he took 2.8 g of 3x rextaliced P2NP
5.8 g of bbq alu foil ( little bit thicker than most others ) amalgamated
the alu in 40ml water + 60 ml ipa with 50 mg Hgcl, heating the mixture was used to get the
the soup to a nice bubbling , by that time the solven had already a greyish color
so the 2,8 g were dissolved in warm ipa ~12ml and added in stages over 5 min
this was allowed to swirl about 2h , then basified with Naoh ( really exotherm rxn cause allot of the alu was still present , next time more Hgcl ... )
after 10 min most alu was dissolved and a fishy rotting smell came from the beaker , tiny droplets of a very slight yellow oil were floating on top
in this stage the beaker was put in the freezer cos swirh had no time for workup
... later the sludge will be et2o extracted ( 2x ) and gasses with hcl

:: >Swirh extracted the whole stuff with washing gas ( just a try )
then gasses with Hcl and got : !!!! nothing .. ( somwhow exspected )
swirh will extract with H2o / H2so4 to see what he can rescue from this stuff...

icecool · Insistent Chemist

What is it about the water thing.
How much water should one have in it's reaction.
SWIM heard about an equilibrium that is there too much water will turn the imine back into the nitrostyrene and too little water won't form the imine.
SWIM wants to reduce 2,5-DMNS 10g of it.
What should he use he thought about 80mg HgCl2 in IPA and the 10g 2,5-DMNS in 100ml acetic acid and 60ml IPA.
And this time as a solvent for the reduction 99% pure IPA insted of EtOH of 90% pure (10% water).
So this time IPA (best solvent for amalgams) this time SWIM really wants to get a good yield because 2,5-DMNS is expensive for him.
So :

10g 2,5-DMNS
100ml GAA 99%
60ml IPA
20g Al folded 4 times.
enough IPA to cover the Al
Overhead stirring is used.
80mg HgCl2 maybe more will be used later on.

What about the stirring does it need to be constant on or every 15minutes a stirr for 3 minutes or so?
What temperature is the best?
Add all the nitrostyrene at once or in portions?
Does there need to be additional water and if so how much?

Radiumhero · Fri Oct 07, 2005 12:05 am

well swirhs dog gave it a constant stirr !
Well in the beginning right off the hotplate hed had to stay away from stirring too much or he would have spread the stuff on the floor ...
but after cooling down he could set it on his magstir and have it do its work without problems but sont forget to add Hgcl2 and some solvent ( swirh used to add etoh )
this should give u good yield

icecool · Insistent Chemist

SWIM only has acces to EtOH 90% with a bit of ether and MEK and also quite some water.
That's why he was going to use IPA but what about the water and the temperature etc?

Radiumhero · Fri Oct 07, 2005 12:15 am

no water was added during rxn the tmp wasnt noticed , but it was about ~65°
then the whole mixture was taken off plate the Hgvl2 was dissolved and the first portion of Al added