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-nitro The same thing has also been tried with a oxime. It smelled sucess too. |
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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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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! |
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Strontium (Member) 04-20-00 19:00 No 108282 |
Re: NiCl2 to activate Al instead of Hg?........ | Bookmark | ||||||
Thanx Chem guy Os, daddy dearest!! I´m always speculating quite a bit on what the product might be. Strontium |
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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? |
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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. But from the oxime reduction there was a HCl salt snowing in the solvent mixture.
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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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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. |
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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.
I quote the text from the Rhodium page: '"U-N-AA 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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