Sciencemadness Discussion Board

Reducing organic compounds with devarda's alloy?

Boffis - 8-11-2021 at 02:10

I have a large jar of powdered Devarda's alloy that was once used for the analysis of nitrite and nitrate salts. Recently I was wondering if it could be used to replace other aluminium alloys as a reducing agent for organic compounds such as nitro compounds in alkaline solution.

Has anyone ever tried it as an organic reducing agent? It has been discussed before on SM as a possible reducing agent for PETN but I thick the alkaline solution required would cleave the nitrate groups in this case. I would imagine that it functionality would be similar to Al-Ga and Al-amalgam.

Fery - 8-11-2021 at 02:45

Hi Boffis, I did not try, but have this - reduction of nitrobenzene to hydrazobenzene using Dewarda's alloy.

Attachment: vogel1958.pdf (927kB)
This file has been downloaded 220 times

Boffis - 8-11-2021 at 05:46

Hi Fery, many thanks for that paper! I think I can feel some experimental chemistry coming on! Devarda's alloy crops up on ebay fairly frequently in the UK and its cheap.

arkoma - 8-11-2021 at 21:12

Interesting. I've got a furnace that gets hot enough to melt copper.

SWIM - 9-11-2021 at 00:09

Might not even need to reach copper's melting point.

Molten aluminum will dissolve copper to some extent.

I just checked and the alloy boils at 906 C, so hopefully it can be made below that temperature.


arkoma - 9-11-2021 at 10:52

melted 25gm Cu, 22.5gm Al and 2.5gm Zn. Now just to figure out a use for it........



devardas.jpg - 2.5MB

Fery - 9-11-2021 at 11:45

arkoma - well done and beautiful! Is the alloy fragile so could be grounded to dust? All my Dewarda's alloys are are very fine particle dust. Or is it so reactive that it does not require pulverization?

SWIM - 9-11-2021 at 16:10

So is this stuff basically an activated form of aluminum?

Like aluminum/mercury amalgam?

Be nice to find a less toxic substitute for that.

edit: I have heard of copper activated zinc being used for some of the same reactions as Al/Hg.



[Edited on 10-11-2021 by SWIM]

Triflic Acid - 9-11-2021 at 17:05

Would be interesting if this could be used for a Clemmensen reduction, since it has a decent zinc quantity

Boffis - 9-11-2021 at 20:09

@ Swim, yes I think you are right that's why I was asking about its similarity with aluminium amalgam etc. Given the amount of discussion on this forum given over to the aluminium-gallium alloy and related mixtures I thought this stuff seem to be a more accessible and cheaper alternative still. Also its mercury free!