emrebjk
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CH3 to NH2
I'm trying to convert CH3 gropup to NH2 group. How can ı do this. Thanks for your help.
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sparkgap
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Transmutation! That's the key!!!1! Just like turning lead into gold!
 
Seriously, giving more details would really be appreciated.
sparky (^_^)
"What's UTFSE? I keep hearing about it, but I can't be arsed to search for the answer..."
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emrebjk
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My molecule is CH3-C=O-C=O-CH3 (butane-2,3-dione). I'm trying to convert these CH3 groups to NH2. Can I do this? How?
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garage chemist
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You're just trying to make oxamide? Well, for this there are some much cheaper precursors.
And I know no suitable procedure to turn butane-2,3-dione into oxamide.
To make your desired molecule, you esterify oxalic acid with methanol to dimethyl oxalate, isolate it and react this with concentrated aqueous
ammonia. There you've got your NH2-CO-CO-NH2.
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emrebjk
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it looks easy. just try. thanx
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emrebjk
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I try your way. saomething white occurs when i added NH3 to oxalicacid+methanol. But first I evaporate methanol then add NH3. I'll go IR. thanx
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garage chemist
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You are not supposed to just throw the things together.
You are supposed to do a SYNTHESIS of Dimethyl oxalate first, with subsequent isolation and purification of the product.
Of course you will need an esterification catalyst, like H2SO4, and a means of separating the product from the excess of methanol that you will have
to use.
The reaction of dimethyl oxalate with aqueous ammonia produces your compound, but you still need to isolate and purify it.
What is the solubility of your product in water?
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emrebjk
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I'll ask you that. I think I need to use a catalyst. I separate methanol in rotary evaparator. then add NH3 and white presipitate occur. I think this
is oxalic acid  . It's solubility in water is good
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garage chemist
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The precipitate is ammonium oxalate, since the oxalic acid didn't react with the methanol. Refluxing with H2SO4 present is required.
Go find a synthesis for dimethyl oxalate. I think orgsyn has one.
And the Organikum should have one too.
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sparkgap
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emrebjk, I believe you would have gotten appropriate answers promptly if you elaborated from the first post. garage chemist is right, throwing all of
those together won't be productive.
Makine esters is pretty straightforward the Fischer way. Alcohol, acid (one of these should be in slight excess to drive the equilibrium forward), and
sulfuric acid as catalyst, reflux, distill. If you're patient enough, great. garage chemist already pointed out where to look for details.
Oh, and there are better uses for diacetyl than conversion to oxamide. Mmm... butter. 
sparky (^_^)
"What's UTFSE? I keep hearing about it, but I can't be arsed to search for the answer..."
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emrebjk
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thank you so much. everything is ok.I manage. thanx for garage chemists and also sparkgap. Maybe I'll write your name in my thesis
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Madandcrazy
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Guys, is the dimethyloxalate a practically suggestion within -O- ?
I know somewhat a methyl group can converted in a amino group when the startingmaterial dissolved in a mixture of TFAA (triflouroacetic acid)  , a amin and a solvent or a acid (contingently HNO3 or H2SO4 for insensitive
chemicals).
Example possibly:
- 2-methyl-1,3-cyclopropanediamin is nitrated with 95 % HNO3 and acetic acid anhydride to 2-methyl-cyclopropan-1,3-dinitrodiazin.
- the filtered 2-methyl-cyclopropane-1,3-dinitrodiazin is
dissolved in the TFAA converting mixture, maybe
TFAA,AAAH, HNO3 and than treated with H2O2 .
[Edited on 5-2-2006 by Madandcrazy]
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