Retard-3000
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Nitroaromatic Reduction w/Sn
Does anyone have a diagram or know how Nitroaromatic reductions using Tin occur/proceed, such as the reduction of Nitrobenzene ?
I understand that the Tin reacts with the Hydrochloric acid producing Tin (II) Chloride and Hydrogen gas, then the Tin (II) Chloride reduces the nitro
group whilst subsequently being oxidised to Tin (IV) Chloride. I'm not sure how it occurs exactly though, does anyone know how the reaction would
proceed step by step?
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redox
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Here is commonly accepted mechanism. The tin is the source of electrons, and the Hydrochloric acid is the source of hydronium ions. The methanol is
the solvent and source of H atoms.
EDIT: That picture showed up a little small, I don't know how to make it bigger.
[Edited on 14-8-2011 by redox]
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Retard-3000
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Thank you so much  , I was able to find a larger image of the picture on google
by searching for the name of the image 
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Nicodem
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Since when is that a "commonly accepted mechanism"? Where is the reference? Why would the intermediate radicals abstract alpha-hydrogens from methanol
when they can just receive another easy to get electron from the metal surface? And why would the mechanism involve alcohols when the reduction works
just fine in their absence?
What is wrong with the general metal dissolving reaction mechanism for nitrobenzene to aniline reduction as presented in March's (chapter
19-45 Reduction of Nitro Compounds to Amines)? At least it involves no hydrogen abstraction, only simple electron and proton
transfers, just as one would intuitively expect. The 6th edition has a nice scheme (page 1818) for the proposed mechanism and gives this reference:
H.O. House, Modern Synthetic Reactions, 2nd ed., W.A. Benjamin, NY, 1972, p. 211. I suppose that is not the original reference, so those
interested will have to hunt down the reference to the primary literature to get an answer.
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redox
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I am currently on vacation, when I get back home I'll look at my copy of March. I'm sorry, I just googled the mechanism and found that picture. My
sincerest apologies Nicodem if this is not the correct mechanism.
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Davyrocket
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Hi all in scieance madness....I know this is a old thread...but
However I too am intreasted in the Reduction of SnCl
With nitro compounds.
I have read about lead free solder wich contains a fairly high % of sn
But there would still be a lot of impurity,and would assume this would
Have a yield effect on final product.
I have also read some where that SnCl it is superior to al/hg reduction
As nitro compounds go and due to the high toxcity of the al/hg
This would be a much better experiment for me to use with my new glassware
I recived for my birthday
Also has any one experienced the two diffrent reactions.
I am not in no means looking for spoon feeding, I am willing to study what ever method is best I know what rout to try.
ie...is there a yield difference between them...is there a scale difference
Is ther much difference on work ups....
thx the rocket
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