ber117
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tailing tlc (nitration product)
hi.. my final project is nitrating 2-mercato-1-methylimidazole with nitric acid/sulfuric acid, so the product should be
2-mercapto-1-methy-5-nitroimidazole (if i'm not wrong..)
the product is yellow high viscos fluid (that's i got in the lab)
i had a problem when i did tlc, there are tailing.. i used n-hexane:EtOAc 1:1 as mobile phase.
anybody have ideas to separate the product from precursors and nitric acid/sulfuric acid excess ?
thanks before.. 
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vulture
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Please take care of your posts when asking questions, clarity is important.
Did you perform TLC of the reaction mixture? Did you neutralize the product?
One shouldn't accept or resort to the mutilation of science to appease the mentally impaired.
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Nicodem
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This is the first time ever that I hear of mercaptanes being nitrated with the thiol group remaining unaffected. Please provide some supporting
reference. Do you see the thiol proton in NMR? How come the product is liquid? Can't you crystallize it? It should be solid.
To prevent tailing on TLC, try adding a few % acetic or trifluoroacetic acid to the mobile phase.
With extraction after neutralization to the isoelectric point.
But then again, your post does not make much sense. How do you know the product is "yellow high viscos fluid" if you still don't know how to isolate
it? How did you isolate it in the first place?
PS: I'm moving this thread to Beginners section as it is referenceless.
…there is a human touch of the cultist “believer” in every theorist that he must struggle against as being
unworthy of the scientist. Some of the greatest men of science have publicly repudiated a theory which earlier they hotly defended. In this lies their
scientific temper, not in the scientific defense of the theory. - Weston La Barre (Ghost Dance, 1972)
Read the The ScienceMadness Guidelines!
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Nicodem
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Thread Moved
8-3-2011 at 09:24 |
vulture
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| Quote: |
Can't you crystallize it? It should be solid. |
I am speculating that it is actually in the protonated form, in which case imidazoles are quite likely to form ionic liquids.
One shouldn't accept or resort to the mutilation of science to appease the mentally impaired.
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