Strontium (Member)
04-18-00 09:23
No 108279
      NiCl2 to activate Al instead of Hg?........  Bookmark   

Thanx to our good reverend here, I tried the following:

2g 1-(none-of-your-business-phenyl)-2-nitroethene, 100ml MeOH, 1g NiCl2, and 20ml 30%HCl was happily stirring in a 250ml E-beaker. To this, 4g of Al foil in 1X1cm pieces was added during 20 min. Temp rose from 22deg C to 35 deg C. After the addition was complete the solution was left to stir for 30 min.
10%(aq)NaOH was added until no more Al(OH)3 was precipitated, filtred, filter cake washed with 30ml MeOH. To the filtrate 300ml water wad added in a sep funnel, pH was checked and adjusted to 11 with 10%(aq)NaOH.
The aqueous soln was extracted with 2X30ml DCM. DCM dried with MgSO4 and evaporated under reduced pressure. A VERY curious nose put over the flask....Whoooa, is there an amine in there or what!!!=)
Crystallisation haven`t been performed yet.

The same thing has also been tried with a oxime. It smelled sucess too.
Im quite sure the ratios of reactants wasnt optional. But it was just a rough trial.


This is too good to be true.
Can we FINALLY leave the fucking Hg to the devil?!?


Strontium

 
 
 
 
    CHEM GUY
(Member)
04-18-00 23:35
No 108280
      Re: NiCl2 to activate Al instead of Hg?........  Bookmark   

Ahhh!  We are talking Urushibara catalyst!  Yes!

Adding the NiCl2 to the Al (or vise versus) does not create an amalgam like with HgCl2 and Al, but rather it preceptiates out finely divided Ni.  When you add the NaOH to the Ni and Al the NaOH reacts with the Al to produce monotomic hydrogen  and the Ni helps catalyze the hydrogenation of the nitro group. 

Congrate this is the first sucess story that I've heard with Urushibara nickel catlaysts, bu that is mostly because the interest in them has been with the hydrolysis of benzyl alcohols which apparently requires high tempatures and pressures that some bees are not willing to create, about 40 atm and 30-80 degrees.

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Everything in this post is for informational purposes only, and is not intended to facilitate illegal activity.  I've done nothing illegal and nor should you.  In addition to that anything that appears not to have informational value, but instead implies something about my actions or anyone else is fictional and serves only as entertainment value.
If you are in violation of any law by reading this leave now.

 
 
 
 
    Osmium
(Moderator)
04-19-00 13:12
No 108281
      Re: NiCl2 to activate Al instead of Hg?........  Bookmark   

Do not speculate about the nature of your products until you crystallised, purified and bioassayed them!
 
 
 
 
    Strontium
(Member)
04-20-00 19:00
No 108282
      Re: NiCl2 to activate Al instead of Hg?........  Bookmark   

Thanx Chem guy

Os, daddy dearest!!  Im always speculating quite a bit on what the product might be.
Bioassaying...Oh no, not me. That might be illegal you see. There are other ways to confirm structure you know. By the way, why the nasty tone? All I said was that it stunk  amine in that flask. Are we a little cranky here?

Strontium

 
 
 
 
    CHEM GUY
(Member)
04-27-00 09:57
No 108283
      Re: NiCl2 to activate Al instead of Hg?........  Bookmark   

How did you form the (?)-2-nitropropane?
 
 
 
 
    Strontium
(Member)
04-28-00 17:33
No 108284
      Re: NiCl2 to activate Al instead of Hg?........  Bookmark   

Chem guy:
It was a blah blah-2-nitroethene. And it was made the usual way, aldehyde, nitroalkane, and catalyst.

Now the sad part.
It was apparently not an amine formed when the 2-nitroalkene was reduced. Or at least there was no HCl salt formed, which could be crystallized from IPA/Et2O.

But from the oxime reduction there was a HCl salt snowing in the solvent mixture.
Proper analysis will be performed soon.


Strontium

 
 
 
 
    CHEM GUY
(Member)
04-28-00 22:05
No 108285
      Re: NiCl2 to activate Al instead of Hg?........  Bookmark   

I don't understand.  Your procedure at the top doesn't list any gassing?  From the procedure you listed there wouldn't be any HCl amine salt formed, just a plain amine...

The Oxime reduction?  What further reduction did you perform to get a product?  Or did you get a product?

I would imagine that the said procedure that you posted at the top of the page would at least reduce the double bond.  I would also think that it would reduce the nitro part as well.  How an oxime would form is beyond me though?

Please clarify as I would love to know the (hypothical) realization of a method of this sort

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Everything in this post is for informational purposes only, and is not intended to facilitate illegal activity.  I've done nothing illegal and nor should you.  In addition to that anything that appears not to have informational value, but instead implies something about my actions or anyone else is fictional and serves only as entertainment value.
If you are in violation of any law by reading this leave now.

 
 
 
 
    Rhodium
(Administrator)
04-28-00 23:53
No 108286
      Re: NiCl2 to activate Al instead of Hg?........  Bookmark   

1) He took the product from the top reaction and gassed it. No salt was formed.

2) He also tried the procedure on an oxime (synthed before) and this gave a HCl salt, which indicates success.

 
 
 
 
    CHEM GUY
(Member)
04-29-00 01:03
No 108287
      Re: NiCl2 to activate Al instead of Hg?........  Bookmark   

No salt was formed after gassing?  What was the amine smell?

I wouldn't think that a Urushibara catalyst generated in situ would cleave nitro-compound.

Maybe there was just enough amine formed to stink, but not enough to crystalize.  Or perhaps the filteration process to get rid of the Al2O3 and Ni was done crappy, so a lot of the product got left behind.


The Urushibara reduction of the oxime worked, but the nitro-reduction did not?  That sounds weird. 

I quote the text from the Rhodium page:

'"U-N-AA
U-N-AA is prepared by warming the precepitated nickel which is
deposited from nickel chloride solution by aluminium grains, with
acetic acid saturated with sodium chloride. It consists of aluminium
grains coated by nickel metal, as the nickel metal deposited on
aluminium grains does not separate from the latter, which remain
undisolved after acetic acid treatment owing to the mild reaction
between aluminium metal and acetic acid. As the aluminium grains which
 support the the nickel metalact as a carrier, U-N-AA can most
conveniently be used for a vapor-phase reduction. It has been noted
that the use of U-N-AA is not confined to vapor-phase reduction; it is
also suitable for liquid-phase hydrogenation at room tempature and
atmosphere presure. This can be seen from the reduction of
nitrobenzene in EtOH in the presence of U-N-AA, gives aniline in 70%
yield."'

And the method of preparation that he uses should be more active...  With the exception that the reduction is carried out in a basic medium!  Maybe that's it. 

Try the same reduction but add H2SO4 instead of the NaOH.  Gas evolution will be less vigorous, but the reaction will be acid catalyzed.  Maybe the formation of a NaOH-nitro complex is inhebiting the reduction.  This complex wouldn't be formed with the oxime, therefore being consistant with the experimental outcome (the oxime is also more easily reduced, but let's ignore that for now)


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Everything in this post is for informational purposes only, and is not intended to facilitate illegal activity.  I've done nothing illegal and nor should you.  In addition to that anything that appears not to have informational value, but instead implies something about my actions or anyone else is fictional and serves only as entertainment value.
If you are in violation of any law by reading this leave now.